From e270475f0fce4e9fb477becb2a04b541d4c8e3a5 Mon Sep 17 00:00:00 2001
From: Maximilian Stefanac <137301184+corporatemax@users.noreply.github.com>
Date: Mon, 25 Nov 2024 09:58:22 +0100
Subject: [PATCH 1/6] add error messages from syslog drains to the app log
 stream

---
 src/cmd/syslog-agent/app/syslog_agent.go      | 27 +++++-----
 src/pkg/egress/syslog/loggregator_emitter.go  | 40 +++++++++++++++
 .../egress/syslog/loggregator_emitter_test.go | 44 ++++++++++++++++
 src/pkg/egress/syslog/retry_writer.go         |  5 ++
 src/pkg/egress/syslog/retry_writer_test.go    |  3 +-
 src/pkg/egress/syslog/syslog_connector.go     | 50 ++++---------------
 .../egress/syslog/syslog_connector_test.go    |  9 ++--
 src/pkg/egress/syslog/writer_factory.go       | 12 +++--
 src/pkg/egress/syslog/writer_factory_test.go  | 18 +++----
 9 files changed, 138 insertions(+), 70 deletions(-)
 create mode 100644 src/pkg/egress/syslog/loggregator_emitter.go
 create mode 100644 src/pkg/egress/syslog/loggregator_emitter_test.go

diff --git a/src/cmd/syslog-agent/app/syslog_agent.go b/src/cmd/syslog-agent/app/syslog_agent.go
index 277bbdeb1..eae083652 100644
--- a/src/cmd/syslog-agent/app/syslog_agent.go
+++ b/src/cmd/syslog-agent/app/syslog_agent.go
@@ -57,18 +57,6 @@ func NewSyslogAgent(
 	m Metrics,
 	l *log.Logger,
 ) *SyslogAgent {
-	internalTlsConfig, externalTlsConfig := drainTLSConfig(cfg)
-	writerFactory := syslog.NewWriterFactory(
-		internalTlsConfig,
-		externalTlsConfig,
-		syslog.NetworkTimeoutConfig{
-			Keepalive:    10 * time.Second,
-			DialTimeout:  10 * time.Second,
-			WriteTimeout: 10 * time.Second,
-		},
-		m,
-	)
-
 	ingressTLSConfig, err := loggregator.NewIngressTLSConfig(
 		cfg.GRPC.CAFile,
 		cfg.GRPC.CertFile,
@@ -86,12 +74,25 @@ func NewSyslogAgent(
 		l.Panicf("failed to create log client for syslog connector: %q", err)
 	}
 
+	internalTlsConfig, externalTlsConfig := drainTLSConfig(cfg)
+	writerFactory := syslog.NewWriterFactory(
+		internalTlsConfig,
+		externalTlsConfig,
+		syslog.NetworkTimeoutConfig{
+			Keepalive:    10 * time.Second,
+			DialTimeout:  10 * time.Second,
+			WriteTimeout: 10 * time.Second,
+		},
+		m,
+		syslog.NewLoggregatorEmitter(logClient, "syslog_agent"),
+	)
+
 	connector := syslog.NewSyslogConnector(
 		cfg.DrainSkipCertVerify,
 		timeoutwaitgroup.New(time.Minute),
 		writerFactory,
 		m,
-		syslog.WithLogClient(logClient, "syslog_agent"),
+		syslog.WithLoggregatorEmitter(syslog.NewLoggregatorEmitter(logClient, "syslog_agent")),
 	)
 
 	var cacheClient *cache.CacheClient
diff --git a/src/pkg/egress/syslog/loggregator_emitter.go b/src/pkg/egress/syslog/loggregator_emitter.go
new file mode 100644
index 000000000..63347df54
--- /dev/null
+++ b/src/pkg/egress/syslog/loggregator_emitter.go
@@ -0,0 +1,40 @@
+package syslog
+
+import (
+	"code.cloudfoundry.org/go-loggregator/v10"
+)
+
+// LogClient is used to emit logs.
+type LogClient interface {
+	EmitLog(message string, opts ...loggregator.EmitLogOption)
+}
+
+type LoggregatorEmitter struct {
+	logClient   LogClient
+	sourceIndex string
+}
+
+// WriteLog writes a message in the application log stream using a LogClient.
+func (appLogEmitter *LoggregatorEmitter) WriteLog(appID string, message string) {
+	if appLogEmitter.logClient == nil || appID == "" {
+		return
+	}
+
+	option := loggregator.WithAppInfo(appID, "LGR", "")
+	appLogEmitter.logClient.EmitLog(message, option)
+
+	option = loggregator.WithAppInfo(
+		appID,
+		"SYS",
+		appLogEmitter.sourceIndex,
+	)
+	appLogEmitter.logClient.EmitLog(message, option)
+}
+
+// NewLoggregatorEmitter creates a new LoggregatorEmitter.
+func NewLoggregatorEmitter(logClient LogClient, sourceIndex string) LoggregatorEmitter {
+	return LoggregatorEmitter{
+		logClient:   logClient,
+		sourceIndex: sourceIndex,
+	}
+}
diff --git a/src/pkg/egress/syslog/loggregator_emitter_test.go b/src/pkg/egress/syslog/loggregator_emitter_test.go
new file mode 100644
index 000000000..558a68bd8
--- /dev/null
+++ b/src/pkg/egress/syslog/loggregator_emitter_test.go
@@ -0,0 +1,44 @@
+package syslog_test
+
+import (
+	"code.cloudfoundry.org/loggregator-agent-release/src/pkg/egress/syslog"
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("Loggregator Emitter", func() {
+	Describe("WriteLog()", func() {
+		It("emits a log message", func() {
+			logClient := NewSpyLogClient()
+			emitter := syslog.NewLoggregatorEmitter(logClient, "0")
+
+			emitter.WriteLog("app-id", "some-message")
+
+			messages := logClient.message()
+			appIDs := logClient.appID()
+			sourceTypes := logClient.sourceType()
+			Expect(messages).To(HaveLen(2))
+			Expect(messages[0]).To(Equal("some-message"))
+			Expect(messages[1]).To(Equal("some-message"))
+			Expect(appIDs[0]).To(Equal("app-id"))
+			Expect(appIDs[1]).To(Equal("app-id"))
+			Expect(sourceTypes).To(HaveKey("LGR"))
+			Expect(sourceTypes).To(HaveKey("SYS"))
+		})
+
+		It("does not emit a log message if the appID is empty", func() {
+			logClient := NewSpyLogClient()
+			emitter := syslog.NewLoggregatorEmitter(logClient, "0")
+
+			emitter.WriteLog("", "some-message")
+
+			messages := logClient.message()
+			appIDs := logClient.appID()
+			sourceTypes := logClient.sourceType()
+			Expect(messages).To(HaveLen(0))
+			Expect(appIDs).To(HaveLen(0))
+			Expect(sourceTypes).ToNot(HaveKey("LGR"))
+			Expect(sourceTypes).ToNot(HaveKey("SYS"))
+		})
+	})
+})
diff --git a/src/pkg/egress/syslog/retry_writer.go b/src/pkg/egress/syslog/retry_writer.go
index c97e81cb0..f5c31dc32 100644
--- a/src/pkg/egress/syslog/retry_writer.go
+++ b/src/pkg/egress/syslog/retry_writer.go
@@ -1,6 +1,7 @@
 package syslog
 
 import (
+	"fmt"
 	"log"
 	"math"
 	"time"
@@ -21,6 +22,7 @@ type RetryWriter struct {
 	retryDuration RetryDuration
 	maxRetries    int
 	binding       *URLBinding
+	emitter       LoggregatorEmitter
 }
 
 func NewRetryWriter(
@@ -28,12 +30,14 @@ func NewRetryWriter(
 	retryDuration RetryDuration,
 	maxRetries int,
 	writer egress.WriteCloser,
+	emitter LoggregatorEmitter,
 ) (egress.WriteCloser, error) {
 	return &RetryWriter{
 		Writer:        writer,
 		retryDuration: retryDuration,
 		maxRetries:    maxRetries,
 		binding:       urlBinding,
+		emitter:       emitter,
 	}, nil
 }
 
@@ -55,6 +59,7 @@ func (r *RetryWriter) Write(e *loggregator_v2.Envelope) error {
 
 		sleepDuration := r.retryDuration(i)
 		log.Printf(logTemplate, r.binding.URL.Host, sleepDuration, err)
+		r.emitter.WriteLog(e.SourceId, fmt.Sprintf(logTemplate, r.binding.URL.Host, sleepDuration, err))
 
 		time.Sleep(sleepDuration)
 	}
diff --git a/src/pkg/egress/syslog/retry_writer_test.go b/src/pkg/egress/syslog/retry_writer_test.go
index 65c4752f2..64299bd37 100644
--- a/src/pkg/egress/syslog/retry_writer_test.go
+++ b/src/pkg/egress/syslog/retry_writer_test.go
@@ -175,7 +175,7 @@ type spyLogClient struct {
 	_sourceInstance map[string]struct{}
 }
 
-func newSpyLogClient() *spyLogClient {
+func NewSpyLogClient() *spyLogClient {
 	return &spyLogClient{
 		_sourceType:     make(map[string]struct{}),
 		_sourceInstance: make(map[string]struct{}),
@@ -257,5 +257,6 @@ func buildRetryWriter(
 		syslog.RetryDuration(buildDelay(delayMultiplier)),
 		maxRetries,
 		w,
+		syslog.LoggregatorEmitter{},
 	)
 }
diff --git a/src/pkg/egress/syslog/syslog_connector.go b/src/pkg/egress/syslog/syslog_connector.go
index bb06b34a1..50a58858e 100644
--- a/src/pkg/egress/syslog/syslog_connector.go
+++ b/src/pkg/egress/syslog/syslog_connector.go
@@ -2,14 +2,12 @@ package syslog
 
 import (
 	"fmt"
-	"log"
-
 	"golang.org/x/net/context"
+	"log"
 
 	metrics "code.cloudfoundry.org/go-metric-registry"
 
 	"code.cloudfoundry.org/go-diodes"
-	"code.cloudfoundry.org/go-loggregator/v10"
 	"code.cloudfoundry.org/loggregator-agent-release/src/pkg/egress"
 )
 
@@ -33,32 +31,20 @@ type Credentials struct {
 	CA   string `json:"ca"`
 }
 
-// LogClient is used to emit logs.
-type LogClient interface {
-	EmitLog(message string, opts ...loggregator.EmitLogOption)
-}
-
-// nullLogClient ensures that the LogClient is in fact optional.
-type nullLogClient struct{}
-
-// EmitLog drops all messages into /dev/null.
-func (nullLogClient) EmitLog(message string, opts ...loggregator.EmitLogOption) {
-}
-
 type writerFactory interface {
-	NewWriter(*URLBinding) (egress.WriteCloser, error)
+	NewWriter(*URLBinding, LoggregatorEmitter) (egress.WriteCloser, error)
 }
 
 // SyslogConnector creates the various egress syslog writers.
 type SyslogConnector struct {
 	skipCertVerify bool
-	logClient      LogClient
 	wg             egress.WaitGroup
-	sourceIndex    string
 	writerFactory  writerFactory
+	metricClient   metricClient
 
-	metricClient  metricClient
 	droppedMetric metrics.Counter
+
+	loggregatorEmitter LoggregatorEmitter
 }
 
 // NewSyslogConnector configures and returns a new SyslogConnector.
@@ -78,7 +64,6 @@ func NewSyslogConnector(
 	sc := &SyslogConnector{
 		skipCertVerify: skipCertVerify,
 		wg:             wg,
-		logClient:      nullLogClient{},
 		writerFactory:  f,
 
 		metricClient:  m,
@@ -93,12 +78,11 @@ func NewSyslogConnector(
 // ConnectorOption allows a syslog connector to be customized.
 type ConnectorOption func(*SyslogConnector)
 
-// WithLogClient returns a ConnectorOption that will set up logging for any
+// WithLoggregatorEmitter returns a ConnectorOption that will set up logging for any
 // information about a binding.
-func WithLogClient(logClient LogClient, sourceIndex string) ConnectorOption {
+func WithLoggregatorEmitter(emitter LoggregatorEmitter) ConnectorOption {
 	return func(sc *SyslogConnector) {
-		sc.logClient = logClient
-		sc.sourceIndex = sourceIndex
+		sc.loggregatorEmitter = emitter
 	}
 }
 
@@ -110,7 +94,7 @@ func (w *SyslogConnector) Connect(ctx context.Context, b Binding) (egress.Writer
 		return nil, err
 	}
 
-	writer, err := w.writerFactory.NewWriter(urlBinding)
+	writer, err := w.writerFactory.NewWriter(urlBinding, w.loggregatorEmitter)
 	if err != nil {
 		return nil, err
 	}
@@ -138,7 +122,7 @@ func (w *SyslogConnector) Connect(ctx context.Context, b Binding) (egress.Writer
 		w.droppedMetric.Add(float64(missed))
 		drainDroppedMetric.Add(float64(missed))
 
-		w.emitLoggregatorErrorLog(b.AppId, fmt.Sprintf("%d messages lost for application %s in user provided syslog drain with url %s", missed, b.AppId, anonymousUrl.String()))
+		w.loggregatorEmitter.WriteLog(b.AppId, fmt.Sprintf("%d messages lost for application %s in user provided syslog drain with url %s", missed, b.AppId, anonymousUrl.String()))
 		w.emitStandardOutErrorLog(b.AppId, urlBinding.Scheme(), anonymousUrl.String(), missed)
 	}), w.wg)
 
@@ -151,20 +135,6 @@ func (w *SyslogConnector) Connect(ctx context.Context, b Binding) (egress.Writer
 	return filteredWriter, nil
 }
 
-func (w *SyslogConnector) emitLoggregatorErrorLog(appID, message string) {
-	if appID == "" {
-		return
-	}
-	option := loggregator.WithAppInfo(appID, "LGR", "")
-	w.logClient.EmitLog(message, option)
-
-	option = loggregator.WithAppInfo(
-		appID,
-		"SYS",
-		w.sourceIndex,
-	)
-	w.logClient.EmitLog(message, option)
-}
 func (w *SyslogConnector) emitStandardOutErrorLog(appID, scheme, url string, missed int) {
 	errorAppOrAggregate := fmt.Sprintf("for %s's app drain", appID)
 	if appID == "" {
diff --git a/src/pkg/egress/syslog/syslog_connector_test.go b/src/pkg/egress/syslog/syslog_connector_test.go
index cb58a740d..40b15b946 100644
--- a/src/pkg/egress/syslog/syslog_connector_test.go
+++ b/src/pkg/egress/syslog/syslog_connector_test.go
@@ -172,13 +172,13 @@ var _ = Describe("SyslogConnector", func() {
 		})
 
 		It("emits a LGR and SYS log to the log client about logs that have been dropped", func() {
-			logClient := newSpyLogClient()
+			logClient := NewSpyLogClient()
 			connector := syslog.NewSyslogConnector(
 				true,
 				spyWaitGroup,
 				writerFactory,
 				sm,
-				syslog.WithLogClient(logClient, "3"),
+				syslog.WithLoggregatorEmitter(syslog.NewLoggregatorEmitter(logClient, "3")),
 			)
 
 			binding := syslog.Binding{AppId: "app-id",
@@ -214,13 +214,13 @@ var _ = Describe("SyslogConnector", func() {
 		})
 
 		It("doesn't emit LGR and SYS log to the log client about aggregate drains drops", func() {
-			logClient := newSpyLogClient()
+			logClient := NewSpyLogClient()
 			connector := syslog.NewSyslogConnector(
 				true,
 				spyWaitGroup,
 				writerFactory,
 				sm,
-				syslog.WithLogClient(logClient, "3"),
+				syslog.WithLoggregatorEmitter(syslog.NewLoggregatorEmitter(logClient, "3")),
 			)
 
 			binding := syslog.Binding{Drain: syslog.Drain{Url: "dropping://"}}
@@ -276,6 +276,7 @@ type stubWriterFactory struct {
 
 func (f *stubWriterFactory) NewWriter(
 	urlBinding *syslog.URLBinding,
+	emitter syslog.LoggregatorEmitter,
 ) (egress.WriteCloser, error) {
 	f.called = true
 	return f.writer, f.err
diff --git a/src/pkg/egress/syslog/writer_factory.go b/src/pkg/egress/syslog/writer_factory.go
index 8ec8249ab..5a43b139b 100644
--- a/src/pkg/egress/syslog/writer_factory.go
+++ b/src/pkg/egress/syslog/writer_factory.go
@@ -41,18 +41,20 @@ type WriterFactory struct {
 	externalTlsConfig *tls.Config
 	netConf           NetworkTimeoutConfig
 	m                 metricClient
+	emitter           LoggregatorEmitter
 }
 
-func NewWriterFactory(internalTlsConfig *tls.Config, externalTlsConfig *tls.Config, netConf NetworkTimeoutConfig, m metricClient) WriterFactory {
+func NewWriterFactory(internalTlsConfig *tls.Config, externalTlsConfig *tls.Config, netConf NetworkTimeoutConfig, m metricClient, emitter LoggregatorEmitter) WriterFactory {
 	return WriterFactory{
 		internalTlsConfig: internalTlsConfig,
 		externalTlsConfig: externalTlsConfig,
 		netConf:           netConf,
 		m:                 m,
+		emitter:           emitter,
 	}
 }
 
-func (f WriterFactory) NewWriter(ub *URLBinding) (egress.WriteCloser, error) {
+func (f WriterFactory) NewWriter(ub *URLBinding, emitter LoggregatorEmitter) (egress.WriteCloser, error) {
 	tlsCfg := f.externalTlsConfig.Clone()
 	if ub.InternalTls {
 		tlsCfg = f.internalTlsConfig.Clone()
@@ -60,7 +62,9 @@ func (f WriterFactory) NewWriter(ub *URLBinding) (egress.WriteCloser, error) {
 	if len(ub.Certificate) > 0 && len(ub.PrivateKey) > 0 {
 		cert, err := tls.X509KeyPair(ub.Certificate, ub.PrivateKey)
 		if err != nil {
-			err = NewWriterFactoryErrorf(ub.URL, "failed to load certificate: %s", err.Error())
+			errorMessage := err.Error()
+			err = NewWriterFactoryErrorf(ub.URL, "failed to load certificate: %s", errorMessage)
+			f.emitter.WriteLog(ub.AppID, fmt.Sprintf("failed to load certificate: %s", errorMessage))
 			return nil, err
 		}
 		tlsCfg.Certificates = []tls.Certificate{cert}
@@ -69,6 +73,7 @@ func (f WriterFactory) NewWriter(ub *URLBinding) (egress.WriteCloser, error) {
 		ok := tlsCfg.RootCAs.AppendCertsFromPEM(ub.CA)
 		if !ok {
 			err := NewWriterFactoryErrorf(ub.URL, "failed to load root CA")
+			f.emitter.WriteLog(ub.AppID, "failed to load root CA")
 			return nil, err
 		}
 	}
@@ -140,5 +145,6 @@ func (f WriterFactory) NewWriter(ub *URLBinding) (egress.WriteCloser, error) {
 		ExponentialDuration,
 		maxRetries,
 		w,
+		emitter,
 	)
 }
diff --git a/src/pkg/egress/syslog/writer_factory_test.go b/src/pkg/egress/syslog/writer_factory_test.go
index 5707bbf56..3078e4b90 100644
--- a/src/pkg/egress/syslog/writer_factory_test.go
+++ b/src/pkg/egress/syslog/writer_factory_test.go
@@ -19,7 +19,7 @@ var _ = Describe("EgressFactory", func() {
 
 	BeforeEach(func() {
 		sm = metricsHelpers.NewMetricsRegistry()
-		f = syslog.NewWriterFactory(&tls.Config{}, &tls.Config{}, syslog.NetworkTimeoutConfig{}, sm) //nolint:gosec
+		f = syslog.NewWriterFactory(&tls.Config{}, &tls.Config{}, syslog.NetworkTimeoutConfig{}, sm, syslog.LoggregatorEmitter{}) //nolint:gosec
 	})
 
 	Context("when the url begins with https", func() {
@@ -30,7 +30,7 @@ var _ = Describe("EgressFactory", func() {
 				URL: url,
 			}
 
-			writer, err := f.NewWriter(urlBinding)
+			writer, err := f.NewWriter(urlBinding, syslog.LoggregatorEmitter{})
 			Expect(err).ToNot(HaveOccurred())
 
 			retryWriter, ok := writer.(*syslog.RetryWriter)
@@ -49,7 +49,7 @@ var _ = Describe("EgressFactory", func() {
 				URL: url,
 			}
 
-			writer, err := f.NewWriter(urlBinding)
+			writer, err := f.NewWriter(urlBinding, syslog.LoggregatorEmitter{})
 			Expect(err).ToNot(HaveOccurred())
 
 			retryWriter, ok := writer.(*syslog.RetryWriter)
@@ -68,7 +68,7 @@ var _ = Describe("EgressFactory", func() {
 				URL: url,
 			}
 
-			writer, err := f.NewWriter(urlBinding)
+			writer, err := f.NewWriter(urlBinding, syslog.LoggregatorEmitter{})
 			Expect(err).ToNot(HaveOccurred())
 
 			retryWriter, ok := writer.(*syslog.RetryWriter)
@@ -87,7 +87,7 @@ var _ = Describe("EgressFactory", func() {
 				URL: url,
 			}
 
-			writer, err := f.NewWriter(urlBinding)
+			writer, err := f.NewWriter(urlBinding, syslog.LoggregatorEmitter{})
 			Expect(err).ToNot(HaveOccurred())
 
 			retryWriter, ok := writer.(*syslog.RetryWriter)
@@ -106,7 +106,7 @@ var _ = Describe("EgressFactory", func() {
 					Certificate: []byte("invalid-certificate"),
 				}
 
-				_, err = f.NewWriter(urlBinding)
+				_, err = f.NewWriter(urlBinding, syslog.LoggregatorEmitter{})
 				Expect(err).ToNot(HaveOccurred())
 			})
 		})
@@ -120,7 +120,7 @@ var _ = Describe("EgressFactory", func() {
 					PrivateKey: []byte("invalid-private-key"),
 				}
 
-				_, err = f.NewWriter(urlBinding)
+				_, err = f.NewWriter(urlBinding, syslog.LoggregatorEmitter{})
 				Expect(err).ToNot(HaveOccurred())
 			})
 		})
@@ -143,7 +143,7 @@ var _ = Describe("EgressFactory", func() {
 				urlBinding.CA = []byte("invalid-ca")
 			}
 
-			_, err = f.NewWriter(urlBinding)
+			_, err = f.NewWriter(urlBinding, syslog.LoggregatorEmitter{})
 
 			Expect(err).To(MatchError(expectedErr))
 		},
@@ -169,7 +169,7 @@ var _ = Describe("EgressFactory", func() {
 				AppID: appID,
 			}
 
-			_, err = f.NewWriter(urlBinding)
+			_, err = f.NewWriter(urlBinding, syslog.LoggregatorEmitter{})
 			Expect(err).ToNot(HaveOccurred())
 
 			metric := sm.GetMetric("egress", tags)

From 56e1903b12057369d0159538ec6eaae992689e8c Mon Sep 17 00:00:00 2001
From: Maximilian Stefanac <137301184+corporatemax@users.noreply.github.com>
Date: Mon, 25 Nov 2024 10:44:52 +0100
Subject: [PATCH 2/6] add error messages from filtered binding fetcher to the
 app log stream

---
 src/cmd/syslog-agent/app/syslog_agent.go      |  2 +-
 .../bindings/filtered_binding_fetcher.go      | 10 +++-
 .../bindings/filtered_binding_fetcher_test.go | 50 ++++---------------
 3 files changed, 20 insertions(+), 42 deletions(-)

diff --git a/src/cmd/syslog-agent/app/syslog_agent.go b/src/cmd/syslog-agent/app/syslog_agent.go
index eae083652..cd2a1017c 100644
--- a/src/cmd/syslog-agent/app/syslog_agent.go
+++ b/src/cmd/syslog-agent/app/syslog_agent.go
@@ -113,7 +113,7 @@ func NewSyslogAgent(
 			m,
 			cfg.WarnOnInvalidDrains,
 			l,
-		)
+			syslog.NewLoggregatorEmitter(logClient, "syslog_agent"))
 		cupsFetcher = bindings.NewDrainParamParser(cupsFetcher, cfg.DefaultDrainMetadata)
 	}
 
diff --git a/src/pkg/ingress/bindings/filtered_binding_fetcher.go b/src/pkg/ingress/bindings/filtered_binding_fetcher.go
index 0921c95c3..044fa5f8e 100644
--- a/src/pkg/ingress/bindings/filtered_binding_fetcher.go
+++ b/src/pkg/ingress/bindings/filtered_binding_fetcher.go
@@ -1,6 +1,7 @@
 package bindings
 
 import (
+	"fmt"
 	"log"
 	"net"
 	"net/url"
@@ -34,9 +35,10 @@ type FilteredBindingFetcher struct {
 	invalidDrains     metrics.Gauge
 	blacklistedDrains metrics.Gauge
 	failedHostsCache  *simplecache.SimpleCache[string, bool]
+	emitter           syslog.LoggregatorEmitter
 }
 
-func NewFilteredBindingFetcher(c IPChecker, b binding.Fetcher, m metricsClient, warn bool, lc *log.Logger) *FilteredBindingFetcher {
+func NewFilteredBindingFetcher(c IPChecker, b binding.Fetcher, m metricsClient, warn bool, lc *log.Logger, emitter syslog.LoggregatorEmitter) *FilteredBindingFetcher {
 	opt := metrics.WithMetricLabels(map[string]string{"unit": "total"})
 
 	invalidDrains := m.NewGauge(
@@ -57,6 +59,7 @@ func NewFilteredBindingFetcher(c IPChecker, b binding.Fetcher, m metricsClient,
 		invalidDrains:     invalidDrains,
 		blacklistedDrains: blacklistedDrains,
 		failedHostsCache:  simplecache.New[string, bool](120 * time.Second),
+		emitter:           emitter,
 	}
 }
 
@@ -87,12 +90,14 @@ func (f *FilteredBindingFetcher) FetchBindings() ([]syslog.Binding, error) {
 
 		if invalidScheme(u.Scheme) {
 			f.printWarning("Invalid scheme %s in syslog drain url %s for application %s", u.Scheme, anonymousUrl.String(), b.AppId)
+			f.emitter.WriteLog(b.AppId, fmt.Sprintf("Invalid scheme %s in syslog drain url %s", u.Scheme, anonymousUrl.String()))
 			continue
 		}
 
 		if len(u.Host) == 0 {
 			invalidDrains += 1
 			f.printWarning("No hostname found in syslog drain url %s for application %s", anonymousUrl.String(), b.AppId)
+			f.emitter.WriteLog(b.AppId, fmt.Sprintf("No hostname found in syslog drain url %s", anonymousUrl.String()))
 			continue
 		}
 
@@ -100,6 +105,7 @@ func (f *FilteredBindingFetcher) FetchBindings() ([]syslog.Binding, error) {
 		if exists {
 			invalidDrains += 1
 			f.printWarning("Skipped resolve ip address for syslog drain with url %s for application %s due to prior failure", anonymousUrl.String(), b.AppId)
+			f.emitter.WriteLog(b.AppId, fmt.Sprintf("Skipped resolve ip address for syslog drain with url %s due to prior failure", anonymousUrl.String()))
 			continue
 		}
 
@@ -108,6 +114,7 @@ func (f *FilteredBindingFetcher) FetchBindings() ([]syslog.Binding, error) {
 			invalidDrains += 1
 			f.failedHostsCache.Set(u.Host, true)
 			f.printWarning("Cannot resolve ip address for syslog drain with url %s for application %s", anonymousUrl.String(), b.AppId)
+			f.emitter.WriteLog(b.AppId, fmt.Sprintf("Cannot resolve ip address for syslog drain with url %s", anonymousUrl.String()))
 			continue
 		}
 
@@ -116,6 +123,7 @@ func (f *FilteredBindingFetcher) FetchBindings() ([]syslog.Binding, error) {
 			invalidDrains += 1
 			blacklistedDrains += 1
 			f.printWarning("Resolved ip address for syslog drain with url %s for application %s is blacklisted", anonymousUrl.String(), b.AppId)
+			f.emitter.WriteLog(b.AppId, fmt.Sprintf("Resolved ip address for syslog drain with url %s is blacklisted", anonymousUrl.String()))
 			continue
 		}
 
diff --git a/src/pkg/ingress/bindings/filtered_binding_fetcher_test.go b/src/pkg/ingress/bindings/filtered_binding_fetcher_test.go
index c217d4e84..15bd381a3 100644
--- a/src/pkg/ingress/bindings/filtered_binding_fetcher_test.go
+++ b/src/pkg/ingress/bindings/filtered_binding_fetcher_test.go
@@ -33,7 +33,7 @@ var _ = Describe("FilteredBindingFetcher", func() {
 		}
 		bindingReader := &SpyBindingReader{bindings: input}
 
-		filter = bindings.NewFilteredBindingFetcher(&spyIPChecker{}, bindingReader, metrics, true, log)
+		filter = bindings.NewFilteredBindingFetcher(&spyIPChecker{}, bindingReader, metrics, true, log, syslog.LoggregatorEmitter{})
 		actual, err := filter.FetchBindings()
 
 		Expect(err).ToNot(HaveOccurred())
@@ -43,7 +43,7 @@ var _ = Describe("FilteredBindingFetcher", func() {
 	It("returns an error if the binding reader cannot fetch bindings", func() {
 		bindingReader := &SpyBindingReader{nil, errors.New("Woops")}
 
-		filter := bindings.NewFilteredBindingFetcher(&spyIPChecker{}, bindingReader, metrics, true, log)
+		filter := bindings.NewFilteredBindingFetcher(&spyIPChecker{}, bindingReader, metrics, true, log, syslog.LoggregatorEmitter{})
 		actual, err := filter.FetchBindings()
 
 		Expect(err).To(HaveOccurred())
@@ -64,13 +64,7 @@ var _ = Describe("FilteredBindingFetcher", func() {
 			input := []syslog.Binding{
 				{AppId: "app-id", Hostname: "we.dont.care", Drain: syslog.Drain{Url: "://"}},
 			}
-			filter = bindings.NewFilteredBindingFetcher(
-				&spyIPChecker{},
-				&SpyBindingReader{bindings: input},
-				metrics,
-				warn,
-				log,
-			)
+			filter = bindings.NewFilteredBindingFetcher(&spyIPChecker{}, &SpyBindingReader{bindings: input}, metrics, warn, log, syslog.LoggregatorEmitter{})
 		})
 
 		It("removes the binding", func() {
@@ -108,13 +102,7 @@ var _ = Describe("FilteredBindingFetcher", func() {
 			input := []syslog.Binding{
 				{AppId: "app-id", Hostname: "we.dont.care", Drain: syslog.Drain{Url: "https:///path"}},
 			}
-			filter = bindings.NewFilteredBindingFetcher(
-				&spyIPChecker{},
-				&SpyBindingReader{bindings: input},
-				metrics,
-				warn,
-				log,
-			)
+			filter = bindings.NewFilteredBindingFetcher(&spyIPChecker{}, &SpyBindingReader{bindings: input}, metrics, warn, log, syslog.LoggregatorEmitter{})
 		})
 
 		It("removes the binding", func() {
@@ -163,13 +151,7 @@ var _ = Describe("FilteredBindingFetcher", func() {
 		})
 
 		JustBeforeEach(func() {
-			filter = bindings.NewFilteredBindingFetcher(
-				&spyIPChecker{},
-				&SpyBindingReader{bindings: input},
-				metrics,
-				warn,
-				log,
-			)
+			filter = bindings.NewFilteredBindingFetcher(&spyIPChecker{}, &SpyBindingReader{bindings: input}, metrics, warn, log, syslog.LoggregatorEmitter{})
 		})
 
 		It("ignores the bindings", func() {
@@ -210,13 +192,7 @@ var _ = Describe("FilteredBindingFetcher", func() {
 			input := []syslog.Binding{
 				{AppId: "app-id", Hostname: "we.dont.care", Drain: syslog.Drain{Url: "syslog://some.invalid.host"}},
 			}
-			filter = bindings.NewFilteredBindingFetcher(
-				mockic,
-				&SpyBindingReader{bindings: input},
-				metrics,
-				warn,
-				log,
-			)
+			filter = bindings.NewFilteredBindingFetcher(mockic, &SpyBindingReader{bindings: input}, metrics, warn, log, syslog.LoggregatorEmitter{})
 		})
 
 		It("removes bindings that failed to resolve", func() {
@@ -272,16 +248,10 @@ var _ = Describe("FilteredBindingFetcher", func() {
 				{AppId: "app-id", Hostname: "we.dont.care", Drain: syslog.Drain{Url: "syslog://some.invalid.host"}},
 			}
 
-			filter = bindings.NewFilteredBindingFetcher(
-				&spyIPChecker{
-					checkBlacklistError: errors.New("blacklist error"),
-					resolvedIP:          net.ParseIP("127.0.0.1"),
-				},
-				&SpyBindingReader{bindings: input},
-				metrics,
-				warn,
-				log,
-			)
+			filter = bindings.NewFilteredBindingFetcher(&spyIPChecker{
+				checkBlacklistError: errors.New("blacklist error"),
+				resolvedIP:          net.ParseIP("127.0.0.1"),
+			}, &SpyBindingReader{bindings: input}, metrics, warn, log, syslog.LoggregatorEmitter{})
 		})
 
 		It("removes the binding", func() {

From 8e9af200cb4e53161f8cd47e9f6e60c10b012a7d Mon Sep 17 00:00:00 2001
From: Maximilian Stefanac <137301184+corporatemax@users.noreply.github.com>
Date: Mon, 25 Nov 2024 17:19:55 +0100
Subject: [PATCH 3/6] rename LoggregatorEmitter to AppLogEmitter

---
 ...ggregator_emitter.go => app_log_emitter.go} | 10 +++++-----
 ...emitter_test.go => app_log_emitter_test.go} |  0
 src/pkg/egress/syslog/retry_writer.go          |  4 ++--
 src/pkg/egress/syslog/retry_writer_test.go     |  2 +-
 src/pkg/egress/syslog/syslog_connector.go      |  6 +++---
 src/pkg/egress/syslog/syslog_connector_test.go |  2 +-
 src/pkg/egress/syslog/writer_factory.go        |  6 +++---
 src/pkg/egress/syslog/writer_factory_test.go   | 18 +++++++++---------
 .../bindings/filtered_binding_fetcher.go       |  4 ++--
 .../bindings/filtered_binding_fetcher_test.go  | 14 +++++++-------
 10 files changed, 33 insertions(+), 33 deletions(-)
 rename src/pkg/egress/syslog/{loggregator_emitter.go => app_log_emitter.go} (76%)
 rename src/pkg/egress/syslog/{loggregator_emitter_test.go => app_log_emitter_test.go} (100%)

diff --git a/src/pkg/egress/syslog/loggregator_emitter.go b/src/pkg/egress/syslog/app_log_emitter.go
similarity index 76%
rename from src/pkg/egress/syslog/loggregator_emitter.go
rename to src/pkg/egress/syslog/app_log_emitter.go
index 63347df54..8101fe030 100644
--- a/src/pkg/egress/syslog/loggregator_emitter.go
+++ b/src/pkg/egress/syslog/app_log_emitter.go
@@ -9,13 +9,13 @@ type LogClient interface {
 	EmitLog(message string, opts ...loggregator.EmitLogOption)
 }
 
-type LoggregatorEmitter struct {
+type AppLogEmitter struct {
 	logClient   LogClient
 	sourceIndex string
 }
 
 // WriteLog writes a message in the application log stream using a LogClient.
-func (appLogEmitter *LoggregatorEmitter) WriteLog(appID string, message string) {
+func (appLogEmitter *AppLogEmitter) WriteLog(appID string, message string) {
 	if appLogEmitter.logClient == nil || appID == "" {
 		return
 	}
@@ -31,9 +31,9 @@ func (appLogEmitter *LoggregatorEmitter) WriteLog(appID string, message string)
 	appLogEmitter.logClient.EmitLog(message, option)
 }
 
-// NewLoggregatorEmitter creates a new LoggregatorEmitter.
-func NewLoggregatorEmitter(logClient LogClient, sourceIndex string) LoggregatorEmitter {
-	return LoggregatorEmitter{
+// NewLoggregatorEmitter creates a new AppLogEmitter.
+func NewLoggregatorEmitter(logClient LogClient, sourceIndex string) AppLogEmitter {
+	return AppLogEmitter{
 		logClient:   logClient,
 		sourceIndex: sourceIndex,
 	}
diff --git a/src/pkg/egress/syslog/loggregator_emitter_test.go b/src/pkg/egress/syslog/app_log_emitter_test.go
similarity index 100%
rename from src/pkg/egress/syslog/loggregator_emitter_test.go
rename to src/pkg/egress/syslog/app_log_emitter_test.go
diff --git a/src/pkg/egress/syslog/retry_writer.go b/src/pkg/egress/syslog/retry_writer.go
index f5c31dc32..bf2b6f4df 100644
--- a/src/pkg/egress/syslog/retry_writer.go
+++ b/src/pkg/egress/syslog/retry_writer.go
@@ -22,7 +22,7 @@ type RetryWriter struct {
 	retryDuration RetryDuration
 	maxRetries    int
 	binding       *URLBinding
-	emitter       LoggregatorEmitter
+	emitter       AppLogEmitter
 }
 
 func NewRetryWriter(
@@ -30,7 +30,7 @@ func NewRetryWriter(
 	retryDuration RetryDuration,
 	maxRetries int,
 	writer egress.WriteCloser,
-	emitter LoggregatorEmitter,
+	emitter AppLogEmitter,
 ) (egress.WriteCloser, error) {
 	return &RetryWriter{
 		Writer:        writer,
diff --git a/src/pkg/egress/syslog/retry_writer_test.go b/src/pkg/egress/syslog/retry_writer_test.go
index 64299bd37..89a769c38 100644
--- a/src/pkg/egress/syslog/retry_writer_test.go
+++ b/src/pkg/egress/syslog/retry_writer_test.go
@@ -257,6 +257,6 @@ func buildRetryWriter(
 		syslog.RetryDuration(buildDelay(delayMultiplier)),
 		maxRetries,
 		w,
-		syslog.LoggregatorEmitter{},
+		syslog.AppLogEmitter{},
 	)
 }
diff --git a/src/pkg/egress/syslog/syslog_connector.go b/src/pkg/egress/syslog/syslog_connector.go
index 50a58858e..7a5b216c6 100644
--- a/src/pkg/egress/syslog/syslog_connector.go
+++ b/src/pkg/egress/syslog/syslog_connector.go
@@ -32,7 +32,7 @@ type Credentials struct {
 }
 
 type writerFactory interface {
-	NewWriter(*URLBinding, LoggregatorEmitter) (egress.WriteCloser, error)
+	NewWriter(*URLBinding, AppLogEmitter) (egress.WriteCloser, error)
 }
 
 // SyslogConnector creates the various egress syslog writers.
@@ -44,7 +44,7 @@ type SyslogConnector struct {
 
 	droppedMetric metrics.Counter
 
-	loggregatorEmitter LoggregatorEmitter
+	loggregatorEmitter AppLogEmitter
 }
 
 // NewSyslogConnector configures and returns a new SyslogConnector.
@@ -80,7 +80,7 @@ type ConnectorOption func(*SyslogConnector)
 
 // WithLoggregatorEmitter returns a ConnectorOption that will set up logging for any
 // information about a binding.
-func WithLoggregatorEmitter(emitter LoggregatorEmitter) ConnectorOption {
+func WithLoggregatorEmitter(emitter AppLogEmitter) ConnectorOption {
 	return func(sc *SyslogConnector) {
 		sc.loggregatorEmitter = emitter
 	}
diff --git a/src/pkg/egress/syslog/syslog_connector_test.go b/src/pkg/egress/syslog/syslog_connector_test.go
index 40b15b946..a97e43d15 100644
--- a/src/pkg/egress/syslog/syslog_connector_test.go
+++ b/src/pkg/egress/syslog/syslog_connector_test.go
@@ -276,7 +276,7 @@ type stubWriterFactory struct {
 
 func (f *stubWriterFactory) NewWriter(
 	urlBinding *syslog.URLBinding,
-	emitter syslog.LoggregatorEmitter,
+	emitter syslog.AppLogEmitter,
 ) (egress.WriteCloser, error) {
 	f.called = true
 	return f.writer, f.err
diff --git a/src/pkg/egress/syslog/writer_factory.go b/src/pkg/egress/syslog/writer_factory.go
index 5a43b139b..3a0b73958 100644
--- a/src/pkg/egress/syslog/writer_factory.go
+++ b/src/pkg/egress/syslog/writer_factory.go
@@ -41,10 +41,10 @@ type WriterFactory struct {
 	externalTlsConfig *tls.Config
 	netConf           NetworkTimeoutConfig
 	m                 metricClient
-	emitter           LoggregatorEmitter
+	emitter           AppLogEmitter
 }
 
-func NewWriterFactory(internalTlsConfig *tls.Config, externalTlsConfig *tls.Config, netConf NetworkTimeoutConfig, m metricClient, emitter LoggregatorEmitter) WriterFactory {
+func NewWriterFactory(internalTlsConfig *tls.Config, externalTlsConfig *tls.Config, netConf NetworkTimeoutConfig, m metricClient, emitter AppLogEmitter) WriterFactory {
 	return WriterFactory{
 		internalTlsConfig: internalTlsConfig,
 		externalTlsConfig: externalTlsConfig,
@@ -54,7 +54,7 @@ func NewWriterFactory(internalTlsConfig *tls.Config, externalTlsConfig *tls.Conf
 	}
 }
 
-func (f WriterFactory) NewWriter(ub *URLBinding, emitter LoggregatorEmitter) (egress.WriteCloser, error) {
+func (f WriterFactory) NewWriter(ub *URLBinding, emitter AppLogEmitter) (egress.WriteCloser, error) {
 	tlsCfg := f.externalTlsConfig.Clone()
 	if ub.InternalTls {
 		tlsCfg = f.internalTlsConfig.Clone()
diff --git a/src/pkg/egress/syslog/writer_factory_test.go b/src/pkg/egress/syslog/writer_factory_test.go
index 3078e4b90..0ae34fa82 100644
--- a/src/pkg/egress/syslog/writer_factory_test.go
+++ b/src/pkg/egress/syslog/writer_factory_test.go
@@ -19,7 +19,7 @@ var _ = Describe("EgressFactory", func() {
 
 	BeforeEach(func() {
 		sm = metricsHelpers.NewMetricsRegistry()
-		f = syslog.NewWriterFactory(&tls.Config{}, &tls.Config{}, syslog.NetworkTimeoutConfig{}, sm, syslog.LoggregatorEmitter{}) //nolint:gosec
+		f = syslog.NewWriterFactory(&tls.Config{}, &tls.Config{}, syslog.NetworkTimeoutConfig{}, sm, syslog.AppLogEmitter{}) //nolint:gosec
 	})
 
 	Context("when the url begins with https", func() {
@@ -30,7 +30,7 @@ var _ = Describe("EgressFactory", func() {
 				URL: url,
 			}
 
-			writer, err := f.NewWriter(urlBinding, syslog.LoggregatorEmitter{})
+			writer, err := f.NewWriter(urlBinding, syslog.AppLogEmitter{})
 			Expect(err).ToNot(HaveOccurred())
 
 			retryWriter, ok := writer.(*syslog.RetryWriter)
@@ -49,7 +49,7 @@ var _ = Describe("EgressFactory", func() {
 				URL: url,
 			}
 
-			writer, err := f.NewWriter(urlBinding, syslog.LoggregatorEmitter{})
+			writer, err := f.NewWriter(urlBinding, syslog.AppLogEmitter{})
 			Expect(err).ToNot(HaveOccurred())
 
 			retryWriter, ok := writer.(*syslog.RetryWriter)
@@ -68,7 +68,7 @@ var _ = Describe("EgressFactory", func() {
 				URL: url,
 			}
 
-			writer, err := f.NewWriter(urlBinding, syslog.LoggregatorEmitter{})
+			writer, err := f.NewWriter(urlBinding, syslog.AppLogEmitter{})
 			Expect(err).ToNot(HaveOccurred())
 
 			retryWriter, ok := writer.(*syslog.RetryWriter)
@@ -87,7 +87,7 @@ var _ = Describe("EgressFactory", func() {
 				URL: url,
 			}
 
-			writer, err := f.NewWriter(urlBinding, syslog.LoggregatorEmitter{})
+			writer, err := f.NewWriter(urlBinding, syslog.AppLogEmitter{})
 			Expect(err).ToNot(HaveOccurred())
 
 			retryWriter, ok := writer.(*syslog.RetryWriter)
@@ -106,7 +106,7 @@ var _ = Describe("EgressFactory", func() {
 					Certificate: []byte("invalid-certificate"),
 				}
 
-				_, err = f.NewWriter(urlBinding, syslog.LoggregatorEmitter{})
+				_, err = f.NewWriter(urlBinding, syslog.AppLogEmitter{})
 				Expect(err).ToNot(HaveOccurred())
 			})
 		})
@@ -120,7 +120,7 @@ var _ = Describe("EgressFactory", func() {
 					PrivateKey: []byte("invalid-private-key"),
 				}
 
-				_, err = f.NewWriter(urlBinding, syslog.LoggregatorEmitter{})
+				_, err = f.NewWriter(urlBinding, syslog.AppLogEmitter{})
 				Expect(err).ToNot(HaveOccurred())
 			})
 		})
@@ -143,7 +143,7 @@ var _ = Describe("EgressFactory", func() {
 				urlBinding.CA = []byte("invalid-ca")
 			}
 
-			_, err = f.NewWriter(urlBinding, syslog.LoggregatorEmitter{})
+			_, err = f.NewWriter(urlBinding, syslog.AppLogEmitter{})
 
 			Expect(err).To(MatchError(expectedErr))
 		},
@@ -169,7 +169,7 @@ var _ = Describe("EgressFactory", func() {
 				AppID: appID,
 			}
 
-			_, err = f.NewWriter(urlBinding, syslog.LoggregatorEmitter{})
+			_, err = f.NewWriter(urlBinding, syslog.AppLogEmitter{})
 			Expect(err).ToNot(HaveOccurred())
 
 			metric := sm.GetMetric("egress", tags)
diff --git a/src/pkg/ingress/bindings/filtered_binding_fetcher.go b/src/pkg/ingress/bindings/filtered_binding_fetcher.go
index 044fa5f8e..2a7a8d30d 100644
--- a/src/pkg/ingress/bindings/filtered_binding_fetcher.go
+++ b/src/pkg/ingress/bindings/filtered_binding_fetcher.go
@@ -35,10 +35,10 @@ type FilteredBindingFetcher struct {
 	invalidDrains     metrics.Gauge
 	blacklistedDrains metrics.Gauge
 	failedHostsCache  *simplecache.SimpleCache[string, bool]
-	emitter           syslog.LoggregatorEmitter
+	emitter           syslog.AppLogEmitter
 }
 
-func NewFilteredBindingFetcher(c IPChecker, b binding.Fetcher, m metricsClient, warn bool, lc *log.Logger, emitter syslog.LoggregatorEmitter) *FilteredBindingFetcher {
+func NewFilteredBindingFetcher(c IPChecker, b binding.Fetcher, m metricsClient, warn bool, lc *log.Logger, emitter syslog.AppLogEmitter) *FilteredBindingFetcher {
 	opt := metrics.WithMetricLabels(map[string]string{"unit": "total"})
 
 	invalidDrains := m.NewGauge(
diff --git a/src/pkg/ingress/bindings/filtered_binding_fetcher_test.go b/src/pkg/ingress/bindings/filtered_binding_fetcher_test.go
index 15bd381a3..eb0091659 100644
--- a/src/pkg/ingress/bindings/filtered_binding_fetcher_test.go
+++ b/src/pkg/ingress/bindings/filtered_binding_fetcher_test.go
@@ -33,7 +33,7 @@ var _ = Describe("FilteredBindingFetcher", func() {
 		}
 		bindingReader := &SpyBindingReader{bindings: input}
 
-		filter = bindings.NewFilteredBindingFetcher(&spyIPChecker{}, bindingReader, metrics, true, log, syslog.LoggregatorEmitter{})
+		filter = bindings.NewFilteredBindingFetcher(&spyIPChecker{}, bindingReader, metrics, true, log, syslog.AppLogEmitter{})
 		actual, err := filter.FetchBindings()
 
 		Expect(err).ToNot(HaveOccurred())
@@ -43,7 +43,7 @@ var _ = Describe("FilteredBindingFetcher", func() {
 	It("returns an error if the binding reader cannot fetch bindings", func() {
 		bindingReader := &SpyBindingReader{nil, errors.New("Woops")}
 
-		filter := bindings.NewFilteredBindingFetcher(&spyIPChecker{}, bindingReader, metrics, true, log, syslog.LoggregatorEmitter{})
+		filter := bindings.NewFilteredBindingFetcher(&spyIPChecker{}, bindingReader, metrics, true, log, syslog.AppLogEmitter{})
 		actual, err := filter.FetchBindings()
 
 		Expect(err).To(HaveOccurred())
@@ -64,7 +64,7 @@ var _ = Describe("FilteredBindingFetcher", func() {
 			input := []syslog.Binding{
 				{AppId: "app-id", Hostname: "we.dont.care", Drain: syslog.Drain{Url: "://"}},
 			}
-			filter = bindings.NewFilteredBindingFetcher(&spyIPChecker{}, &SpyBindingReader{bindings: input}, metrics, warn, log, syslog.LoggregatorEmitter{})
+			filter = bindings.NewFilteredBindingFetcher(&spyIPChecker{}, &SpyBindingReader{bindings: input}, metrics, warn, log, syslog.AppLogEmitter{})
 		})
 
 		It("removes the binding", func() {
@@ -102,7 +102,7 @@ var _ = Describe("FilteredBindingFetcher", func() {
 			input := []syslog.Binding{
 				{AppId: "app-id", Hostname: "we.dont.care", Drain: syslog.Drain{Url: "https:///path"}},
 			}
-			filter = bindings.NewFilteredBindingFetcher(&spyIPChecker{}, &SpyBindingReader{bindings: input}, metrics, warn, log, syslog.LoggregatorEmitter{})
+			filter = bindings.NewFilteredBindingFetcher(&spyIPChecker{}, &SpyBindingReader{bindings: input}, metrics, warn, log, syslog.AppLogEmitter{})
 		})
 
 		It("removes the binding", func() {
@@ -151,7 +151,7 @@ var _ = Describe("FilteredBindingFetcher", func() {
 		})
 
 		JustBeforeEach(func() {
-			filter = bindings.NewFilteredBindingFetcher(&spyIPChecker{}, &SpyBindingReader{bindings: input}, metrics, warn, log, syslog.LoggregatorEmitter{})
+			filter = bindings.NewFilteredBindingFetcher(&spyIPChecker{}, &SpyBindingReader{bindings: input}, metrics, warn, log, syslog.AppLogEmitter{})
 		})
 
 		It("ignores the bindings", func() {
@@ -192,7 +192,7 @@ var _ = Describe("FilteredBindingFetcher", func() {
 			input := []syslog.Binding{
 				{AppId: "app-id", Hostname: "we.dont.care", Drain: syslog.Drain{Url: "syslog://some.invalid.host"}},
 			}
-			filter = bindings.NewFilteredBindingFetcher(mockic, &SpyBindingReader{bindings: input}, metrics, warn, log, syslog.LoggregatorEmitter{})
+			filter = bindings.NewFilteredBindingFetcher(mockic, &SpyBindingReader{bindings: input}, metrics, warn, log, syslog.AppLogEmitter{})
 		})
 
 		It("removes bindings that failed to resolve", func() {
@@ -251,7 +251,7 @@ var _ = Describe("FilteredBindingFetcher", func() {
 			filter = bindings.NewFilteredBindingFetcher(&spyIPChecker{
 				checkBlacklistError: errors.New("blacklist error"),
 				resolvedIP:          net.ParseIP("127.0.0.1"),
-			}, &SpyBindingReader{bindings: input}, metrics, warn, log, syslog.LoggregatorEmitter{})
+			}, &SpyBindingReader{bindings: input}, metrics, warn, log, syslog.AppLogEmitter{})
 		})
 
 		It("removes the binding", func() {

From 25b8f3dfd3cf0db68c94b88a50d0fe933398cfeb Mon Sep 17 00:00:00 2001
From: Maximilian Stefanac <137301184+corporatemax@users.noreply.github.com>
Date: Mon, 25 Nov 2024 17:31:36 +0100
Subject: [PATCH 4/6] change format of NewFilteredBindingFetcher calls

---
 src/cmd/syslog-agent/app/syslog_agent.go      |  3 +-
 .../bindings/filtered_binding_fetcher_test.go | 69 ++++++++++++++++---
 2 files changed, 61 insertions(+), 11 deletions(-)

diff --git a/src/cmd/syslog-agent/app/syslog_agent.go b/src/cmd/syslog-agent/app/syslog_agent.go
index cd2a1017c..62c12c519 100644
--- a/src/cmd/syslog-agent/app/syslog_agent.go
+++ b/src/cmd/syslog-agent/app/syslog_agent.go
@@ -113,7 +113,8 @@ func NewSyslogAgent(
 			m,
 			cfg.WarnOnInvalidDrains,
 			l,
-			syslog.NewLoggregatorEmitter(logClient, "syslog_agent"))
+			syslog.NewLoggregatorEmitter(logClient, "syslog_agent"),
+		)
 		cupsFetcher = bindings.NewDrainParamParser(cupsFetcher, cfg.DefaultDrainMetadata)
 	}
 
diff --git a/src/pkg/ingress/bindings/filtered_binding_fetcher_test.go b/src/pkg/ingress/bindings/filtered_binding_fetcher_test.go
index eb0091659..b7c6527d7 100644
--- a/src/pkg/ingress/bindings/filtered_binding_fetcher_test.go
+++ b/src/pkg/ingress/bindings/filtered_binding_fetcher_test.go
@@ -33,7 +33,14 @@ var _ = Describe("FilteredBindingFetcher", func() {
 		}
 		bindingReader := &SpyBindingReader{bindings: input}
 
-		filter = bindings.NewFilteredBindingFetcher(&spyIPChecker{}, bindingReader, metrics, true, log, syslog.AppLogEmitter{})
+		filter = bindings.NewFilteredBindingFetcher(
+			&spyIPChecker{},
+			bindingReader,
+			metrics,
+			true,
+			log,
+			syslog.AppLogEmitter{},
+		)
 		actual, err := filter.FetchBindings()
 
 		Expect(err).ToNot(HaveOccurred())
@@ -43,7 +50,14 @@ var _ = Describe("FilteredBindingFetcher", func() {
 	It("returns an error if the binding reader cannot fetch bindings", func() {
 		bindingReader := &SpyBindingReader{nil, errors.New("Woops")}
 
-		filter := bindings.NewFilteredBindingFetcher(&spyIPChecker{}, bindingReader, metrics, true, log, syslog.AppLogEmitter{})
+		filter := bindings.NewFilteredBindingFetcher(
+			&spyIPChecker{},
+			bindingReader,
+			metrics,
+			true,
+			log,
+			syslog.AppLogEmitter{},
+		)
 		actual, err := filter.FetchBindings()
 
 		Expect(err).To(HaveOccurred())
@@ -64,7 +78,14 @@ var _ = Describe("FilteredBindingFetcher", func() {
 			input := []syslog.Binding{
 				{AppId: "app-id", Hostname: "we.dont.care", Drain: syslog.Drain{Url: "://"}},
 			}
-			filter = bindings.NewFilteredBindingFetcher(&spyIPChecker{}, &SpyBindingReader{bindings: input}, metrics, warn, log, syslog.AppLogEmitter{})
+			filter = bindings.NewFilteredBindingFetcher(
+				&spyIPChecker{},
+				&SpyBindingReader{bindings: input},
+				metrics,
+				warn,
+				log,
+				syslog.AppLogEmitter{},
+			)
 		})
 
 		It("removes the binding", func() {
@@ -102,7 +123,14 @@ var _ = Describe("FilteredBindingFetcher", func() {
 			input := []syslog.Binding{
 				{AppId: "app-id", Hostname: "we.dont.care", Drain: syslog.Drain{Url: "https:///path"}},
 			}
-			filter = bindings.NewFilteredBindingFetcher(&spyIPChecker{}, &SpyBindingReader{bindings: input}, metrics, warn, log, syslog.AppLogEmitter{})
+			filter = bindings.NewFilteredBindingFetcher(
+				&spyIPChecker{},
+				&SpyBindingReader{bindings: input},
+				metrics,
+				warn,
+				log,
+				syslog.AppLogEmitter{},
+			)
 		})
 
 		It("removes the binding", func() {
@@ -151,7 +179,14 @@ var _ = Describe("FilteredBindingFetcher", func() {
 		})
 
 		JustBeforeEach(func() {
-			filter = bindings.NewFilteredBindingFetcher(&spyIPChecker{}, &SpyBindingReader{bindings: input}, metrics, warn, log, syslog.AppLogEmitter{})
+			filter = bindings.NewFilteredBindingFetcher(
+				&spyIPChecker{},
+				&SpyBindingReader{bindings: input},
+				metrics,
+				warn,
+				log,
+				syslog.AppLogEmitter{},
+			)
 		})
 
 		It("ignores the bindings", func() {
@@ -192,7 +227,14 @@ var _ = Describe("FilteredBindingFetcher", func() {
 			input := []syslog.Binding{
 				{AppId: "app-id", Hostname: "we.dont.care", Drain: syslog.Drain{Url: "syslog://some.invalid.host"}},
 			}
-			filter = bindings.NewFilteredBindingFetcher(mockic, &SpyBindingReader{bindings: input}, metrics, warn, log, syslog.AppLogEmitter{})
+			filter = bindings.NewFilteredBindingFetcher(
+				mockic,
+				&SpyBindingReader{bindings: input},
+				metrics,
+				warn,
+				log,
+				syslog.AppLogEmitter{},
+			)
 		})
 
 		It("removes bindings that failed to resolve", func() {
@@ -248,10 +290,17 @@ var _ = Describe("FilteredBindingFetcher", func() {
 				{AppId: "app-id", Hostname: "we.dont.care", Drain: syslog.Drain{Url: "syslog://some.invalid.host"}},
 			}
 
-			filter = bindings.NewFilteredBindingFetcher(&spyIPChecker{
-				checkBlacklistError: errors.New("blacklist error"),
-				resolvedIP:          net.ParseIP("127.0.0.1"),
-			}, &SpyBindingReader{bindings: input}, metrics, warn, log, syslog.AppLogEmitter{})
+			filter = bindings.NewFilteredBindingFetcher(
+				&spyIPChecker{
+					checkBlacklistError: errors.New("blacklist error"),
+					resolvedIP:          net.ParseIP("127.0.0.1"),
+				},
+				&SpyBindingReader{bindings: input},
+				metrics,
+				warn,
+				log,
+				syslog.AppLogEmitter{},
+			)
 		})
 
 		It("removes the binding", func() {

From 1c03a021c940340668719c68cc2d8b4886a57565 Mon Sep 17 00:00:00 2001
From: Maximilian Stefanac <137301184+corporatemax@users.noreply.github.com>
Date: Mon, 25 Nov 2024 17:50:53 +0100
Subject: [PATCH 5/6] rename references to AppLogEmitter

---
 src/cmd/syslog-agent/app/syslog_agent.go             |  6 +++---
 src/pkg/egress/syslog/app_log_emitter.go             |  8 ++++----
 src/pkg/egress/syslog/app_log_emitter_test.go        | 10 +++++-----
 src/pkg/egress/syslog/retry_writer.go                |  2 +-
 src/pkg/egress/syslog/syslog_connector.go            | 12 ++++++------
 src/pkg/egress/syslog/syslog_connector_test.go       |  4 ++--
 src/pkg/egress/syslog/writer_factory.go              |  4 ++--
 src/pkg/ingress/bindings/filtered_binding_fetcher.go | 10 +++++-----
 8 files changed, 28 insertions(+), 28 deletions(-)

diff --git a/src/cmd/syslog-agent/app/syslog_agent.go b/src/cmd/syslog-agent/app/syslog_agent.go
index 62c12c519..810433d36 100644
--- a/src/cmd/syslog-agent/app/syslog_agent.go
+++ b/src/cmd/syslog-agent/app/syslog_agent.go
@@ -84,7 +84,7 @@ func NewSyslogAgent(
 			WriteTimeout: 10 * time.Second,
 		},
 		m,
-		syslog.NewLoggregatorEmitter(logClient, "syslog_agent"),
+		syslog.NewAppLogEmitter(logClient, "syslog_agent"),
 	)
 
 	connector := syslog.NewSyslogConnector(
@@ -92,7 +92,7 @@ func NewSyslogAgent(
 		timeoutwaitgroup.New(time.Minute),
 		writerFactory,
 		m,
-		syslog.WithLoggregatorEmitter(syslog.NewLoggregatorEmitter(logClient, "syslog_agent")),
+		syslog.WithAppLogEmitter(syslog.NewAppLogEmitter(logClient, "syslog_agent")),
 	)
 
 	var cacheClient *cache.CacheClient
@@ -113,7 +113,7 @@ func NewSyslogAgent(
 			m,
 			cfg.WarnOnInvalidDrains,
 			l,
-			syslog.NewLoggregatorEmitter(logClient, "syslog_agent"),
+			syslog.NewAppLogEmitter(logClient, "syslog_agent"),
 		)
 		cupsFetcher = bindings.NewDrainParamParser(cupsFetcher, cfg.DefaultDrainMetadata)
 	}
diff --git a/src/pkg/egress/syslog/app_log_emitter.go b/src/pkg/egress/syslog/app_log_emitter.go
index 8101fe030..a31e17ec5 100644
--- a/src/pkg/egress/syslog/app_log_emitter.go
+++ b/src/pkg/egress/syslog/app_log_emitter.go
@@ -14,8 +14,8 @@ type AppLogEmitter struct {
 	sourceIndex string
 }
 
-// WriteLog writes a message in the application log stream using a LogClient.
-func (appLogEmitter *AppLogEmitter) WriteLog(appID string, message string) {
+// EmitLog writes a message in the application log stream using a LogClient.
+func (appLogEmitter *AppLogEmitter) EmitLog(appID string, message string) {
 	if appLogEmitter.logClient == nil || appID == "" {
 		return
 	}
@@ -31,8 +31,8 @@ func (appLogEmitter *AppLogEmitter) WriteLog(appID string, message string) {
 	appLogEmitter.logClient.EmitLog(message, option)
 }
 
-// NewLoggregatorEmitter creates a new AppLogEmitter.
-func NewLoggregatorEmitter(logClient LogClient, sourceIndex string) AppLogEmitter {
+// NewAppLogEmitter creates a new AppLogEmitter.
+func NewAppLogEmitter(logClient LogClient, sourceIndex string) AppLogEmitter {
 	return AppLogEmitter{
 		logClient:   logClient,
 		sourceIndex: sourceIndex,
diff --git a/src/pkg/egress/syslog/app_log_emitter_test.go b/src/pkg/egress/syslog/app_log_emitter_test.go
index 558a68bd8..83904f80c 100644
--- a/src/pkg/egress/syslog/app_log_emitter_test.go
+++ b/src/pkg/egress/syslog/app_log_emitter_test.go
@@ -7,12 +7,12 @@ import (
 )
 
 var _ = Describe("Loggregator Emitter", func() {
-	Describe("WriteLog()", func() {
+	Describe("EmitLog()", func() {
 		It("emits a log message", func() {
 			logClient := NewSpyLogClient()
-			emitter := syslog.NewLoggregatorEmitter(logClient, "0")
+			emitter := syslog.NewAppLogEmitter(logClient, "0")
 
-			emitter.WriteLog("app-id", "some-message")
+			emitter.EmitLog("app-id", "some-message")
 
 			messages := logClient.message()
 			appIDs := logClient.appID()
@@ -28,9 +28,9 @@ var _ = Describe("Loggregator Emitter", func() {
 
 		It("does not emit a log message if the appID is empty", func() {
 			logClient := NewSpyLogClient()
-			emitter := syslog.NewLoggregatorEmitter(logClient, "0")
+			emitter := syslog.NewAppLogEmitter(logClient, "0")
 
-			emitter.WriteLog("", "some-message")
+			emitter.EmitLog("", "some-message")
 
 			messages := logClient.message()
 			appIDs := logClient.appID()
diff --git a/src/pkg/egress/syslog/retry_writer.go b/src/pkg/egress/syslog/retry_writer.go
index bf2b6f4df..055fc0490 100644
--- a/src/pkg/egress/syslog/retry_writer.go
+++ b/src/pkg/egress/syslog/retry_writer.go
@@ -59,7 +59,7 @@ func (r *RetryWriter) Write(e *loggregator_v2.Envelope) error {
 
 		sleepDuration := r.retryDuration(i)
 		log.Printf(logTemplate, r.binding.URL.Host, sleepDuration, err)
-		r.emitter.WriteLog(e.SourceId, fmt.Sprintf(logTemplate, r.binding.URL.Host, sleepDuration, err))
+		r.emitter.EmitLog(e.SourceId, fmt.Sprintf(logTemplate, r.binding.URL.Host, sleepDuration, err))
 
 		time.Sleep(sleepDuration)
 	}
diff --git a/src/pkg/egress/syslog/syslog_connector.go b/src/pkg/egress/syslog/syslog_connector.go
index 7a5b216c6..066e37669 100644
--- a/src/pkg/egress/syslog/syslog_connector.go
+++ b/src/pkg/egress/syslog/syslog_connector.go
@@ -44,7 +44,7 @@ type SyslogConnector struct {
 
 	droppedMetric metrics.Counter
 
-	loggregatorEmitter AppLogEmitter
+	appLogEmitter AppLogEmitter
 }
 
 // NewSyslogConnector configures and returns a new SyslogConnector.
@@ -78,11 +78,11 @@ func NewSyslogConnector(
 // ConnectorOption allows a syslog connector to be customized.
 type ConnectorOption func(*SyslogConnector)
 
-// WithLoggregatorEmitter returns a ConnectorOption that will set up logging for any
+// WithAppLogEmitter returns a ConnectorOption that will set up logging for any
 // information about a binding.
-func WithLoggregatorEmitter(emitter AppLogEmitter) ConnectorOption {
+func WithAppLogEmitter(emitter AppLogEmitter) ConnectorOption {
 	return func(sc *SyslogConnector) {
-		sc.loggregatorEmitter = emitter
+		sc.appLogEmitter = emitter
 	}
 }
 
@@ -94,7 +94,7 @@ func (w *SyslogConnector) Connect(ctx context.Context, b Binding) (egress.Writer
 		return nil, err
 	}
 
-	writer, err := w.writerFactory.NewWriter(urlBinding, w.loggregatorEmitter)
+	writer, err := w.writerFactory.NewWriter(urlBinding, w.appLogEmitter)
 	if err != nil {
 		return nil, err
 	}
@@ -122,7 +122,7 @@ func (w *SyslogConnector) Connect(ctx context.Context, b Binding) (egress.Writer
 		w.droppedMetric.Add(float64(missed))
 		drainDroppedMetric.Add(float64(missed))
 
-		w.loggregatorEmitter.WriteLog(b.AppId, fmt.Sprintf("%d messages lost for application %s in user provided syslog drain with url %s", missed, b.AppId, anonymousUrl.String()))
+		w.appLogEmitter.EmitLog(b.AppId, fmt.Sprintf("%d messages lost for application %s in user provided syslog drain with url %s", missed, b.AppId, anonymousUrl.String()))
 		w.emitStandardOutErrorLog(b.AppId, urlBinding.Scheme(), anonymousUrl.String(), missed)
 	}), w.wg)
 
diff --git a/src/pkg/egress/syslog/syslog_connector_test.go b/src/pkg/egress/syslog/syslog_connector_test.go
index a97e43d15..dbe6c7148 100644
--- a/src/pkg/egress/syslog/syslog_connector_test.go
+++ b/src/pkg/egress/syslog/syslog_connector_test.go
@@ -178,7 +178,7 @@ var _ = Describe("SyslogConnector", func() {
 				spyWaitGroup,
 				writerFactory,
 				sm,
-				syslog.WithLoggregatorEmitter(syslog.NewLoggregatorEmitter(logClient, "3")),
+				syslog.WithAppLogEmitter(syslog.NewAppLogEmitter(logClient, "3")),
 			)
 
 			binding := syslog.Binding{AppId: "app-id",
@@ -220,7 +220,7 @@ var _ = Describe("SyslogConnector", func() {
 				spyWaitGroup,
 				writerFactory,
 				sm,
-				syslog.WithLoggregatorEmitter(syslog.NewLoggregatorEmitter(logClient, "3")),
+				syslog.WithAppLogEmitter(syslog.NewAppLogEmitter(logClient, "3")),
 			)
 
 			binding := syslog.Binding{Drain: syslog.Drain{Url: "dropping://"}}
diff --git a/src/pkg/egress/syslog/writer_factory.go b/src/pkg/egress/syslog/writer_factory.go
index 3a0b73958..4d3e0e0da 100644
--- a/src/pkg/egress/syslog/writer_factory.go
+++ b/src/pkg/egress/syslog/writer_factory.go
@@ -64,7 +64,7 @@ func (f WriterFactory) NewWriter(ub *URLBinding, emitter AppLogEmitter) (egress.
 		if err != nil {
 			errorMessage := err.Error()
 			err = NewWriterFactoryErrorf(ub.URL, "failed to load certificate: %s", errorMessage)
-			f.emitter.WriteLog(ub.AppID, fmt.Sprintf("failed to load certificate: %s", errorMessage))
+			f.emitter.EmitLog(ub.AppID, fmt.Sprintf("failed to load certificate: %s", errorMessage))
 			return nil, err
 		}
 		tlsCfg.Certificates = []tls.Certificate{cert}
@@ -73,7 +73,7 @@ func (f WriterFactory) NewWriter(ub *URLBinding, emitter AppLogEmitter) (egress.
 		ok := tlsCfg.RootCAs.AppendCertsFromPEM(ub.CA)
 		if !ok {
 			err := NewWriterFactoryErrorf(ub.URL, "failed to load root CA")
-			f.emitter.WriteLog(ub.AppID, "failed to load root CA")
+			f.emitter.EmitLog(ub.AppID, "failed to load root CA")
 			return nil, err
 		}
 	}
diff --git a/src/pkg/ingress/bindings/filtered_binding_fetcher.go b/src/pkg/ingress/bindings/filtered_binding_fetcher.go
index 2a7a8d30d..db400de2b 100644
--- a/src/pkg/ingress/bindings/filtered_binding_fetcher.go
+++ b/src/pkg/ingress/bindings/filtered_binding_fetcher.go
@@ -90,14 +90,14 @@ func (f *FilteredBindingFetcher) FetchBindings() ([]syslog.Binding, error) {
 
 		if invalidScheme(u.Scheme) {
 			f.printWarning("Invalid scheme %s in syslog drain url %s for application %s", u.Scheme, anonymousUrl.String(), b.AppId)
-			f.emitter.WriteLog(b.AppId, fmt.Sprintf("Invalid scheme %s in syslog drain url %s", u.Scheme, anonymousUrl.String()))
+			f.emitter.EmitLog(b.AppId, fmt.Sprintf("Invalid scheme %s in syslog drain url %s", u.Scheme, anonymousUrl.String()))
 			continue
 		}
 
 		if len(u.Host) == 0 {
 			invalidDrains += 1
 			f.printWarning("No hostname found in syslog drain url %s for application %s", anonymousUrl.String(), b.AppId)
-			f.emitter.WriteLog(b.AppId, fmt.Sprintf("No hostname found in syslog drain url %s", anonymousUrl.String()))
+			f.emitter.EmitLog(b.AppId, fmt.Sprintf("No hostname found in syslog drain url %s", anonymousUrl.String()))
 			continue
 		}
 
@@ -105,7 +105,7 @@ func (f *FilteredBindingFetcher) FetchBindings() ([]syslog.Binding, error) {
 		if exists {
 			invalidDrains += 1
 			f.printWarning("Skipped resolve ip address for syslog drain with url %s for application %s due to prior failure", anonymousUrl.String(), b.AppId)
-			f.emitter.WriteLog(b.AppId, fmt.Sprintf("Skipped resolve ip address for syslog drain with url %s due to prior failure", anonymousUrl.String()))
+			f.emitter.EmitLog(b.AppId, fmt.Sprintf("Skipped resolve ip address for syslog drain with url %s due to prior failure", anonymousUrl.String()))
 			continue
 		}
 
@@ -114,7 +114,7 @@ func (f *FilteredBindingFetcher) FetchBindings() ([]syslog.Binding, error) {
 			invalidDrains += 1
 			f.failedHostsCache.Set(u.Host, true)
 			f.printWarning("Cannot resolve ip address for syslog drain with url %s for application %s", anonymousUrl.String(), b.AppId)
-			f.emitter.WriteLog(b.AppId, fmt.Sprintf("Cannot resolve ip address for syslog drain with url %s", anonymousUrl.String()))
+			f.emitter.EmitLog(b.AppId, fmt.Sprintf("Cannot resolve ip address for syslog drain with url %s", anonymousUrl.String()))
 			continue
 		}
 
@@ -123,7 +123,7 @@ func (f *FilteredBindingFetcher) FetchBindings() ([]syslog.Binding, error) {
 			invalidDrains += 1
 			blacklistedDrains += 1
 			f.printWarning("Resolved ip address for syslog drain with url %s for application %s is blacklisted", anonymousUrl.String(), b.AppId)
-			f.emitter.WriteLog(b.AppId, fmt.Sprintf("Resolved ip address for syslog drain with url %s is blacklisted", anonymousUrl.String()))
+			f.emitter.EmitLog(b.AppId, fmt.Sprintf("Resolved ip address for syslog drain with url %s is blacklisted", anonymousUrl.String()))
 			continue
 		}
 

From 9f789db548342896fb90af564c66c50d7ba3a9bf Mon Sep 17 00:00:00 2001
From: Maximilian Stefanac <137301184+corporatemax@users.noreply.github.com>
Date: Wed, 27 Nov 2024 11:48:58 +0100
Subject: [PATCH 6/6] move spyLogClient to testhelper package

---
 src/internal/testhelper/spy_log_client.go     | 82 +++++++++++++++++++
 src/pkg/egress/syslog/app_log_emitter_test.go | 17 ++--
 src/pkg/egress/syslog/retry_writer_test.go    | 77 -----------------
 .../egress/syslog/syslog_connector_test.go    | 23 +++---
 4 files changed, 103 insertions(+), 96 deletions(-)
 create mode 100644 src/internal/testhelper/spy_log_client.go

diff --git a/src/internal/testhelper/spy_log_client.go b/src/internal/testhelper/spy_log_client.go
new file mode 100644
index 000000000..0faba6b91
--- /dev/null
+++ b/src/internal/testhelper/spy_log_client.go
@@ -0,0 +1,82 @@
+package testhelper
+
+import (
+	"code.cloudfoundry.org/go-loggregator/v10"
+	v2 "code.cloudfoundry.org/go-loggregator/v10/rpc/loggregator_v2"
+	"sync"
+)
+
+type spyLogClient struct {
+	mu       sync.Mutex
+	_message []string
+	_appID   []string
+
+	// We use maps to ensure that we can query the keys
+	_sourceType     map[string]struct{}
+	_sourceInstance map[string]struct{}
+}
+
+func NewSpyLogClient() *spyLogClient {
+	return &spyLogClient{
+		_sourceType:     make(map[string]struct{}),
+		_sourceInstance: make(map[string]struct{}),
+	}
+}
+
+func (s *spyLogClient) EmitLog(message string, opts ...loggregator.EmitLogOption) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	env := &v2.Envelope{
+		Tags: make(map[string]string),
+	}
+
+	for _, o := range opts {
+		o(env)
+	}
+
+	s._message = append(s._message, message)
+	s._appID = append(s._appID, env.SourceId)
+	s._sourceType[env.GetTags()["source_type"]] = struct{}{}
+	s._sourceInstance[env.GetInstanceId()] = struct{}{}
+}
+
+func (s *spyLogClient) Message() []string {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	return s._message
+}
+
+func (s *spyLogClient) AppID() []string {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	return s._appID
+}
+
+func (s *spyLogClient) SourceType() map[string]struct{} {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	// Copy map so the orig does not escape the mutex and induce a race.
+	m := make(map[string]struct{})
+	for k := range s._sourceType {
+		m[k] = struct{}{}
+	}
+
+	return m
+}
+
+func (s *spyLogClient) SourceInstance() map[string]struct{} {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	// Copy map so the orig does not escape the mutex and induce a race.
+	m := make(map[string]struct{})
+	for k := range s._sourceInstance {
+		m[k] = struct{}{}
+	}
+
+	return m
+}
diff --git a/src/pkg/egress/syslog/app_log_emitter_test.go b/src/pkg/egress/syslog/app_log_emitter_test.go
index 83904f80c..18873410d 100644
--- a/src/pkg/egress/syslog/app_log_emitter_test.go
+++ b/src/pkg/egress/syslog/app_log_emitter_test.go
@@ -1,6 +1,7 @@
 package syslog_test
 
 import (
+	"code.cloudfoundry.org/loggregator-agent-release/src/internal/testhelper"
 	"code.cloudfoundry.org/loggregator-agent-release/src/pkg/egress/syslog"
 	. "github.com/onsi/ginkgo/v2"
 	. "github.com/onsi/gomega"
@@ -9,14 +10,14 @@ import (
 var _ = Describe("Loggregator Emitter", func() {
 	Describe("EmitLog()", func() {
 		It("emits a log message", func() {
-			logClient := NewSpyLogClient()
+			logClient := testhelper.NewSpyLogClient()
 			emitter := syslog.NewAppLogEmitter(logClient, "0")
 
 			emitter.EmitLog("app-id", "some-message")
 
-			messages := logClient.message()
-			appIDs := logClient.appID()
-			sourceTypes := logClient.sourceType()
+			messages := logClient.Message()
+			appIDs := logClient.AppID()
+			sourceTypes := logClient.SourceType()
 			Expect(messages).To(HaveLen(2))
 			Expect(messages[0]).To(Equal("some-message"))
 			Expect(messages[1]).To(Equal("some-message"))
@@ -27,14 +28,14 @@ var _ = Describe("Loggregator Emitter", func() {
 		})
 
 		It("does not emit a log message if the appID is empty", func() {
-			logClient := NewSpyLogClient()
+			logClient := testhelper.NewSpyLogClient()
 			emitter := syslog.NewAppLogEmitter(logClient, "0")
 
 			emitter.EmitLog("", "some-message")
 
-			messages := logClient.message()
-			appIDs := logClient.appID()
-			sourceTypes := logClient.sourceType()
+			messages := logClient.Message()
+			appIDs := logClient.AppID()
+			sourceTypes := logClient.SourceType()
 			Expect(messages).To(HaveLen(0))
 			Expect(appIDs).To(HaveLen(0))
 			Expect(sourceTypes).ToNot(HaveKey("LGR"))
diff --git a/src/pkg/egress/syslog/retry_writer_test.go b/src/pkg/egress/syslog/retry_writer_test.go
index 89a769c38..03063506f 100644
--- a/src/pkg/egress/syslog/retry_writer_test.go
+++ b/src/pkg/egress/syslog/retry_writer_test.go
@@ -3,11 +3,9 @@ package syslog_test
 import (
 	"errors"
 	"net/url"
-	"sync"
 	"sync/atomic"
 	"time"
 
-	"code.cloudfoundry.org/go-loggregator/v10"
 	v2 "code.cloudfoundry.org/go-loggregator/v10/rpc/loggregator_v2"
 	"code.cloudfoundry.org/loggregator-agent-release/src/pkg/egress"
 	"code.cloudfoundry.org/loggregator-agent-release/src/pkg/egress/syslog"
@@ -165,81 +163,6 @@ func (s *spyWriteCloser) WriteAttempts() int {
 	return int(atomic.LoadInt64(&s.writeAttempts))
 }
 
-type spyLogClient struct {
-	mu       sync.Mutex
-	_message []string
-	_appID   []string
-
-	// We use maps to ensure that we can query the keys
-	_sourceType     map[string]struct{}
-	_sourceInstance map[string]struct{}
-}
-
-func NewSpyLogClient() *spyLogClient {
-	return &spyLogClient{
-		_sourceType:     make(map[string]struct{}),
-		_sourceInstance: make(map[string]struct{}),
-	}
-}
-
-func (s *spyLogClient) EmitLog(message string, opts ...loggregator.EmitLogOption) {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-
-	env := &v2.Envelope{
-		Tags: make(map[string]string),
-	}
-
-	for _, o := range opts {
-		o(env)
-	}
-
-	s._message = append(s._message, message)
-	s._appID = append(s._appID, env.SourceId)
-	s._sourceType[env.GetTags()["source_type"]] = struct{}{}
-	s._sourceInstance[env.GetInstanceId()] = struct{}{}
-}
-
-func (s *spyLogClient) message() []string {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-
-	return s._message
-}
-
-func (s *spyLogClient) appID() []string {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-
-	return s._appID
-}
-
-func (s *spyLogClient) sourceType() map[string]struct{} {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-
-	// Copy map so the orig does not escape the mutex and induce a race.
-	m := make(map[string]struct{})
-	for k := range s._sourceType {
-		m[k] = struct{}{}
-	}
-
-	return m
-}
-
-func (s *spyLogClient) sourceInstance() map[string]struct{} {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-
-	// Copy map so the orig does not escape the mutex and induce a race.
-	m := make(map[string]struct{})
-	for k := range s._sourceInstance {
-		m[k] = struct{}{}
-	}
-
-	return m
-}
-
 func buildDelay(multiplier time.Duration) func(int) time.Duration {
 	return func(attempt int) time.Duration {
 		return time.Duration(attempt) * multiplier
diff --git a/src/pkg/egress/syslog/syslog_connector_test.go b/src/pkg/egress/syslog/syslog_connector_test.go
index dbe6c7148..46f553f01 100644
--- a/src/pkg/egress/syslog/syslog_connector_test.go
+++ b/src/pkg/egress/syslog/syslog_connector_test.go
@@ -1,6 +1,7 @@
 package syslog_test
 
 import (
+	"code.cloudfoundry.org/loggregator-agent-release/src/internal/testhelper"
 	"errors"
 	"fmt"
 	"io"
@@ -172,7 +173,7 @@ var _ = Describe("SyslogConnector", func() {
 		})
 
 		It("emits a LGR and SYS log to the log client about logs that have been dropped", func() {
-			logClient := NewSpyLogClient()
+			logClient := testhelper.NewSpyLogClient()
 			connector := syslog.NewSyslogConnector(
 				true,
 				spyWaitGroup,
@@ -201,20 +202,20 @@ var _ = Describe("SyslogConnector", func() {
 				}
 			}(writer)
 
-			Eventually(logClient.message).Should(ContainElement(MatchRegexp("\\d messages lost for application (.*) in user provided syslog drain with url")))
-			Eventually(logClient.appID).Should(ContainElement("app-id"))
+			Eventually(logClient.Message).Should(ContainElement(MatchRegexp("\\d messages lost for application (.*) in user provided syslog drain with url")))
+			Eventually(logClient.AppID).Should(ContainElement("app-id"))
 
-			Eventually(logClient.sourceType).Should(HaveLen(2))
-			Eventually(logClient.sourceType).Should(HaveKey("LGR"))
-			Eventually(logClient.sourceType).Should(HaveKey("SYS"))
+			Eventually(logClient.SourceType).Should(HaveLen(2))
+			Eventually(logClient.SourceType).Should(HaveKey("LGR"))
+			Eventually(logClient.SourceType).Should(HaveKey("SYS"))
 
-			Eventually(logClient.sourceInstance).Should(HaveLen(2))
-			Eventually(logClient.sourceInstance).Should(HaveKey(""))
-			Eventually(logClient.sourceInstance).Should(HaveKey("3"))
+			Eventually(logClient.SourceInstance).Should(HaveLen(2))
+			Eventually(logClient.SourceInstance).Should(HaveKey(""))
+			Eventually(logClient.SourceInstance).Should(HaveKey("3"))
 		})
 
 		It("doesn't emit LGR and SYS log to the log client about aggregate drains drops", func() {
-			logClient := NewSpyLogClient()
+			logClient := testhelper.NewSpyLogClient()
 			connector := syslog.NewSyslogConnector(
 				true,
 				spyWaitGroup,
@@ -239,7 +240,7 @@ var _ = Describe("SyslogConnector", func() {
 				}
 			}(writer)
 
-			Consistently(logClient.message).ShouldNot(ContainElement(MatchRegexp("\\d messages lost for application (.*) in user provided syslog drain with url")))
+			Consistently(logClient.Message()).ShouldNot(ContainElement(MatchRegexp("\\d messages lost for application (.*) in user provided syslog drain with url")))
 		})
 
 		It("does not panic on unknown dropped metrics", func() {