fix(ui): Add support for bash href. Fixes ##2100 (#2105)

cmd/argo/commands/server.go

@@ -1,6 +1,7 @@
 package commands
 
 import (
+	"os"
 	"time"
 
 	"github.com/argoproj/pkg/cli"
@@ -22,6 +23,7 @@ func NewServerCommand() *cobra.Command {
 		authMode         string
 		configMap        string
 		port             int
+		baseHRef         string
 		namespaced       bool   // --namespaced
 		managedNamespace string // --managed-namespace
 	)
@@ -60,9 +62,15 @@ func NewServerCommand() *cobra.Command {
 				managedNamespace = namespace
 			}
 
-			log.WithFields(log.Fields{"namespace": namespace, "managedNamespace": managedNamespace}).Info()
+			log.WithFields(log.Fields{
+				"authMode":         authMode,
+				"namespace":        namespace,
+				"managedNamespace": managedNamespace,
+				"baseHRef":         baseHRef}).
+				Info()
 
 			opts := apiserver.ArgoServerOpts{
+				BaseHRef:         baseHRef,
 				Namespace:        namespace,
 				WfClientSet:      wflientset,
 				KubeClientset:    kubeConfig,
@@ -80,6 +88,11 @@ func NewServerCommand() *cobra.Command {
 	}
 
 	command.Flags().IntVarP(&port, "port", "p", 2746, "Port to listen on")
+	baseHref, ok := os.LookupEnv("BASE_HREF")
+	if !ok {
+		baseHRef = "/"
+	}
+	command.Flags().StringVar(&baseHRef, "basehref", baseHref, "Value for base href in index.html. Used if the server is running behind reverse proxy under subpath different from /. Defaults to the environment variable BASE_HREF.")
 	command.Flags().StringVar(&authMode, "auth-mode", "server", "API server authentication mode. One of: client|server|hybrid")
 	command.Flags().StringVar(&configMap, "configmap", "workflow-controller-configmap", "Name of K8s configmap to retrieve workflow controller configuration")
 	command.Flags().StringVar(&logLevel, "loglevel", "info", "Set the logging level. One of: debug|info|warn|error")

server/apiserver/argoserver.go

@@ -40,6 +40,7 @@ import (
 )
 
 type argoServer struct {
+	baseHRef         string
 	namespace        string
 	managedNamespace string
 	kubeClientset    *kubernetes.Clientset
@@ -49,6 +50,7 @@ type argoServer struct {
 }
 
 type ArgoServerOpts struct {
+	BaseHRef         string
 	Namespace        string
 	KubeClientset    *kubernetes.Clientset
 	WfClientSet      *versioned.Clientset
@@ -60,6 +62,7 @@ type ArgoServerOpts struct {
 
 func NewArgoServer(opts ArgoServerOpts) *argoServer {
 	return &argoServer{
+		baseHRef:         opts.BaseHRef,
 		namespace:        opts.Namespace,
 		managedNamespace: opts.ManagedNamespace,
 		kubeClientset:    opts.KubeClientset,
@@ -218,7 +221,7 @@ func (as *argoServer) newHTTPServer(ctx context.Context, port int, artifactServe
 	mux.Handle("/api/", gwmux)
 	mux.HandleFunc("/artifacts/", artifactServer.GetArtifact)
 	mux.HandleFunc("/artifacts-by-uid/", artifactServer.GetArtifactByUID)
-	mux.HandleFunc("/", static.ServerFiles)
+	mux.HandleFunc("/", static.NewFilesServer(as.baseHRef).ServerFiles)
 	return &httpServer
 }
 

server/static/response-rewriter.go

@@ -0,0 +1,23 @@
+package static
+
+import (
+	"bytes"
+	"net/http"
+	"strconv"
+
+	log "github.com/sirupsen/logrus"
+)
+
+type responseRewriter struct {
+	http.ResponseWriter
+	old []byte
+	new []byte
+}
+
+func (w *responseRewriter) Write(a []byte) (int, error) {
+	b := bytes.Replace(a, w.old, w.new, 1)
+	// status code and headers are printed out when we write data
+	w.Header().Set("Content-Length", strconv.Itoa(len(b)))
+	log.WithFields(log.Fields{"a": string(a), "b": string(b)}).Info()
+	return w.ResponseWriter.Write(b)
+}

server/static/static.go

@@ -1,16 +1,32 @@
 package static
 
 import (
+	"fmt"
 	"net/http"
 	"strings"
 )
 
-func ServerFiles(w http.ResponseWriter, r *http.Request) {
+type FilesServer struct {
+	baseHRef string
+}
+
+func NewFilesServer(baseHRef string) *FilesServer {
+	return &FilesServer{baseHRef}
+}
+
+func (s *FilesServer) ServerFiles(w http.ResponseWriter, r *http.Request) {
 
 	// this hack allows us to server the routes (e.g. /workflows) with the index file
 	if !strings.Contains(r.URL.Path, ".") {
 		r.URL.Path = "index.html"
 	}
+
+	if r.URL.Path == "index.html" {
+		// hack to prevent ServerHTTP from giving us gzipped content which we can do our search-and-replace on
+		r.Header.Del("Accept-Encoding")
+		w = &responseRewriter{ResponseWriter: w, old: []byte(`<base href="/">`), new: []byte(fmt.Sprintf(`<base href="%s">`, s.baseHRef))}
+	}
+
 	// in my IDE (IntelliJ) the next line is red for some reason - but this is fine
 	ServeHTTP(w, r)
 }