Limit names and labels to 63 characters

pkg/collector/labels.go

@@ -15,9 +15,8 @@
 package collector
 
 import (
-	"fmt"
-
 	"github.com/open-telemetry/opentelemetry-operator/apis/v1alpha1"
+	"github.com/open-telemetry/opentelemetry-operator/pkg/naming"
 )
 
 // Labels return the common labels to all objects that are part of a managed OpenTelemetryCollector.
@@ -31,7 +30,7 @@ func Labels(instance v1alpha1.OpenTelemetryCollector) map[string]string {
 	}
 
 	base["app.kubernetes.io/managed-by"] = "opentelemetry-operator"
-	base["app.kubernetes.io/instance"] = fmt.Sprintf("%s.%s", instance.Namespace, instance.Name)
+	base["app.kubernetes.io/instance"] = naming.Truncate("%s.%s", 63, instance.Namespace, instance.Name)
 	base["app.kubernetes.io/part-of"] = "opentelemetry"
 	base["app.kubernetes.io/component"] = "opentelemetry-collector"
 

pkg/naming/dns.go

@@ -0,0 +1,46 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package naming
+
+import (
+	"regexp"
+	"strings"
+	"unicode/utf8"
+)
+
+var regex = regexp.MustCompile(`[a-z0-9]`)
+
+// DNSName returns a dns-safe string for the given name.
+// Any char that is not [a-z0-9] is replaced by "-" or "a".
+// Replacement character "a" is used only at the beginning or at the end of the name.
+// The function does not change length of the string.
+// source: https://github.com/jaegertracing/jaeger-operator/blob/91e3b69ee5c8761bbda9d3cf431400a73fc1112a/pkg/util/dns_name.go#L15
+func DNSName(name string) string {
+	var d []rune
+
+	for i, x := range strings.ToLower(name) {
+		if regex.Match([]byte(string(x))) {
+			d = append(d, x)
+		} else {
+			if i == 0 || i == utf8.RuneCountInString(name)-1 {
+				d = append(d, 'a')
+			} else {
+				d = append(d, '-')
+			}
+		}
+	}
+
+	return string(d)
+}

pkg/naming/dns_test.go

@@ -0,0 +1,47 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package naming
+
+import (
+	"regexp"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestDnsName(t *testing.T) {
+	var tests = []struct {
+		in  string
+		out string
+	}{
+		{"simplest", "simplest"},
+		{"instance.with.dots-collector-headless", "instance-with-dots-collector-headless"},
+		{"TestQueryDottedServiceName.With.Dots", "testquerydottedservicename-with-dots"},
+		{"Service🦄", "servicea"},
+		{"📈Stock-Tracker", "astock-tracker"},
+		{"-📈Stock-Tracker", "a-stock-tracker"},
+		{"📈", "a"},
+		{"foo-", "fooa"},
+		{"-foo", "afoo"},
+	}
+	rule, err := regexp.Compile(`^[a-z0-9]([-a-z0-9]*[a-z0-9])?$`)
+	assert.NoError(t, err)
+
+	for _, tt := range tests {
+		assert.Equal(t, tt.out, DNSName(tt.in))
+		matched := rule.Match([]byte(tt.out))
+		assert.True(t, matched, "%v is not a valid name", tt.out)
+	}
+}

pkg/naming/main.go

@@ -16,19 +16,17 @@
 package naming
 
 import (
-	"fmt"
-
 	"github.com/open-telemetry/opentelemetry-operator/apis/v1alpha1"
 )
 
 // ConfigMap builds the name for the config map used in the OpenTelemetryCollector containers.
 func ConfigMap(otelcol v1alpha1.OpenTelemetryCollector) string {
-	return fmt.Sprintf("%s-collector", otelcol.Name)
+	return DNSName(Truncate("%s-collector", 63, otelcol.Name))
 }
 
 // TAConfigMap returns the name for the config map used in the TargetAllocator.
 func TAConfigMap(otelcol v1alpha1.OpenTelemetryCollector) string {
-	return fmt.Sprintf("%s-targetallocator", otelcol.Name)
+	return DNSName(Truncate("%s-targetallocator", 63, otelcol.Name))
 }
 
 // ConfigMapVolume returns the name to use for the config map's volume in the pod.
@@ -53,35 +51,35 @@ func TAContainer() string {
 
 // Collector builds the collector (deployment/daemonset) name based on the instance.
 func Collector(otelcol v1alpha1.OpenTelemetryCollector) string {
-	return fmt.Sprintf("%s-collector", otelcol.Name)
+	return DNSName(Truncate("%s-collector", 63, otelcol.Name))
 }
 
 // TargetAllocator returns the TargetAllocator deployment resource name.
 func TargetAllocator(otelcol v1alpha1.OpenTelemetryCollector) string {
-	return fmt.Sprintf("%s-targetallocator", otelcol.Name)
+	return DNSName(Truncate("%s-targetallocator", 63, otelcol.Name))
 }
 
 // HeadlessService builds the name for the headless service based on the instance.
 func HeadlessService(otelcol v1alpha1.OpenTelemetryCollector) string {
-	return fmt.Sprintf("%s-headless", Service(otelcol))
+	return DNSName(Truncate("%s-headless", 63, Service(otelcol)))
 }
 
 // MonitoringService builds the name for the monitoring service based on the instance.
 func MonitoringService(otelcol v1alpha1.OpenTelemetryCollector) string {
-	return fmt.Sprintf("%s-monitoring", Service(otelcol))
+	return DNSName(Truncate("%s-monitoring", 63, Service(otelcol)))
 }
 
 // Service builds the service name based on the instance.
 func Service(otelcol v1alpha1.OpenTelemetryCollector) string {
-	return fmt.Sprintf("%s-collector", otelcol.Name)
+	return DNSName(Truncate("%s-collector", 63, otelcol.Name))
 }
 
 // TAService returns the name to use for the TargetAllocator service.
 func TAService(otelcol v1alpha1.OpenTelemetryCollector) string {
-	return fmt.Sprintf("%s-targetallocator", otelcol.Name)
+	return DNSName(Truncate("%s-targetallocator", 63, otelcol.Name))
 }
 
 // ServiceAccount builds the service account name based on the instance.
 func ServiceAccount(otelcol v1alpha1.OpenTelemetryCollector) string {
-	return fmt.Sprintf("%s-collector", otelcol.Name)
+	return DNSName(Truncate("%s-collector", 63, otelcol.Name))
 }

pkg/naming/triming.go

@@ -0,0 +1,72 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package naming
+
+import (
+	"fmt"
+	"regexp"
+)
+
+var regexpEndReplace, regexpBeginReplace *regexp.Regexp
+
+func init() {
+	regexpEndReplace, _ = regexp.Compile("[^A-Za-z0-9]+$")
+	regexpBeginReplace, _ = regexp.Compile("^[^A-Za-z0-9]+")
+}
+
+// Truncate will shorten the length of the instance name so that it contains at most max chars when combined with the fixed part
+// If the fixed part is already bigger than the max, this function is noop.
+// source: https://github.com/jaegertracing/jaeger-operator/blob/91e3b69ee5c8761bbda9d3cf431400a73fc1112a/pkg/util/truncate.go#L17
+func Truncate(format string, max int, values ...interface{}) string {
+	var truncated []interface{}
+	result := fmt.Sprintf(format, values...)
+
+	if excess := len(result) - max; excess > 0 {
+		// we try to reduce the first string we find
+		for _, value := range values {
+			if excess == 0 {
+				continue
+			}
+
+			if s, ok := value.(string); ok {
+				if len(s) > excess {
+					value = s[:len(s)-excess]
+					excess = 0
+				} else {
+					value = "" // skip this value entirely
+					excess = excess - len(s)
+				}
+			}
+
+			truncated = append(truncated, value)
+		}
+
+		result = fmt.Sprintf(format, truncated...)
+	}
+
+	// if at this point, the result is still bigger than max, apply a hard cap:
+	if len(result) > max {
+		return result[:max]
+	}
+
+	return trimNonAlphaNumeric(result)
+}
+
+// trimNonAlphaNumeric remove all non-alphanumeric values from start and end of the string
+// source: https://github.com/jaegertracing/jaeger-operator/blob/91e3b69ee5c8761bbda9d3cf431400a73fc1112a/pkg/util/truncate.go#L53
+func trimNonAlphaNumeric(text string) string {
+	newText := regexpEndReplace.ReplaceAllString(text, "")
+	return regexpBeginReplace.ReplaceAllString(newText, "")
+}

pkg/naming/triming_test.go

@@ -0,0 +1,101 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package naming
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestTruncate(t *testing.T) {
+	for _, tt := range []struct {
+		format   string
+		max      int
+		values   []interface{}
+		expected string
+		cap      string
+	}{
+		{
+			format:   "%s-collector",
+			max:      63,
+			values:   []interface{}{"simplest"},
+			expected: "simplest-collector",
+			cap:      "the standard case",
+		},
+		{
+			format:   "d0c1e62-4d96-11ea-b174-c85b7644b6b5-5d0c1e62-4d96-11ea-b174-c85b7644b6b5",
+			max:      63,
+			values:   []interface{}{},
+			expected: "d0c1e62-4d96-11ea-b174-c85b7644b6b5-5d0c1e62-4d96-11ea-b174-c85",
+			cap:      "first N case",
+		},
+		{
+			format:   "%s-collector",
+			max:      63,
+			values:   []interface{}{"d0c1e62-4d96-11ea-b174-c85b7644b6b5-5d0c1e62-4d96-11ea-b174-c85b7644b6b5"},
+			expected: "d0c1e62-4d96-11ea-b174-c85b7644b6b5-5d0c1e62-4d96-11e-collector",
+			cap:      "instance + fixed within bounds",
+		},
+		{
+			format:   "%s-%s-collector",
+			max:      63,
+			values:   []interface{}{"d0c1e62", "4d96-11ea-b174-c85b7644b6b5-5d0c1e62-4d96-11ea-b174-c85b7644b6b5"},
+			expected: "4d96-11ea-b174-c85b7644b6b5-5d0c1e62-4d96-11ea-b174--collector",
+			cap:      "first value gets dropped, second truncated",
+		},
+		{
+			format:   "%d-%s-collector",
+			max:      63,
+			values:   []interface{}{42, "d0c1e62-4d96-11ea-b174-c85b7644b6b5-5d0c1e62-4d96-11ea-b174-c85b7644b6b5"},
+			expected: "42-d0c1e62-4d96-11ea-b174-c85b7644b6b5-5d0c1e62-4d96--collector",
+			cap:      "first value gets passed, second truncated",
+		},
+	} {
+		assert.Equal(t, tt.expected, Truncate(tt.format, tt.max, tt.values...))
+	}
+}
+
+func TestTrimNonAlphaNumeric(t *testing.T) {
+	tests := []struct {
+		input    string
+		expected string
+	}{
+		{
+			input:    "-%$#ThisIsALabel",
+			expected: "ThisIsALabel",
+		},
+
+		{
+			input:    "label-invalid--_truncated-.",
+			expected: "label-invalid--_truncated",
+		},
+
+		{
+			input:    "--(label-invalid--_truncated-#.1.",
+			expected: "label-invalid--_truncated-#.1",
+		},
+
+		{
+			input:    "12ValidLabel3",
+			expected: "12ValidLabel3",
+		},
+	}
+
+	for _, test := range tests {
+		output := trimNonAlphaNumeric(test.input)
+		assert.Equal(t, test.expected, output)
+	}
+}

pkg/targetallocator/labels.go

@@ -15,9 +15,8 @@
 package targetallocator
 
 import (
-	"fmt"
-
 	"github.com/open-telemetry/opentelemetry-operator/apis/v1alpha1"
+	"github.com/open-telemetry/opentelemetry-operator/pkg/naming"
 )
 
 // Labels return the common labels to all TargetAllocator objects that are part of a managed OpenTelemetryCollector.
@@ -31,7 +30,7 @@ func Labels(instance v1alpha1.OpenTelemetryCollector) map[string]string {
 	}
 
 	base["app.kubernetes.io/managed-by"] = "opentelemetry-operator"
-	base["app.kubernetes.io/instance"] = fmt.Sprintf("%s.%s", instance.Namespace, instance.Name)
+	base["app.kubernetes.io/instance"] = naming.Truncate("%s.%s", 63, instance.Namespace, instance.Name)
 	base["app.kubernetes.io/part-of"] = "opentelemetry"
 	base["app.kubernetes.io/component"] = "opentelemetry-targetallocator"