fix: Custom Styles feature is broken

cmd/argocd-server/commands/argocd_server.go

@@ -63,6 +63,7 @@ func NewCommand() *cobra.Command {
 		frameOptions             string
 		repoServerPlaintext      bool
 		repoServerStrictTLS      bool
+		staticAssetsDir          string
 	)
 	var command = &cobra.Command{
 		Use:               cliName,
@@ -139,6 +140,7 @@ func NewCommand() *cobra.Command {
 				Cache:               cache,
 				XFrameOptions:       frameOptions,
 				RedisClient:         redisClient,
+				StaticAssetsDir:     staticAssetsDir,
 			}
 
 			stats.RegisterStackDumper()
@@ -157,9 +159,7 @@ func NewCommand() *cobra.Command {
 
 	clientConfig = cli.AddKubectlFlagsToCmd(command)
 	command.Flags().BoolVar(&insecure, "insecure", env.ParseBoolFromEnv("ARGOCD_SERVER_INSECURE", false), "Run server without TLS")
-	var staticAssetsDir string
-	command.Flags().StringVar(&staticAssetsDir, "staticassets", "", "Static assets directory path")
-	_ = command.Flags().MarkDeprecated("staticassets", "The --staticassets flag is not longer supported. Static assets are embedded into binary.")
+	command.Flags().StringVar(&staticAssetsDir, "staticassets", env.StringFromEnv("ARGOCD_SERVER_STATIC_ASSETS", "/shared/app"), "Directory path that contains additional static assets")
 	command.Flags().StringVar(&baseHRef, "basehref", env.StringFromEnv("ARGOCD_SERVER_BASEHREF", "/"), "Value for base href in index.html. Used if Argo CD is running behind reverse proxy under subpath different from /")
 	command.Flags().StringVar(&rootPath, "rootpath", env.StringFromEnv("ARGOCD_SERVER_ROOTPATH", ""), "Used if Argo CD is running behind reverse proxy under subpath different from /")
 	command.Flags().StringVar(&cmdutil.LogFormat, "logformat", env.StringFromEnv("ARGOCD_SERVER_LOGFORMAT", "text"), "Set the logging format. One of: text|json")

docs/operator-manual/argocd-cmd-params-cm.yaml

@@ -48,6 +48,8 @@ data:
   server.basehref: "/"
   # Used if Argo CD is running behind reverse proxy under subpath different from /
   server.rootpath: "/"
+  # Directory path that contains additional static assets
+  server.staticassets: "/shared/app"
 
   # Set the logging format. One of: text|json (default "text")
   server.log.format: "text"

docs/operator-manual/custom-styles.md

@@ -88,9 +88,10 @@ spec:
         name: styles
 ```
 
-Note that the CSS file should be mounted within a subdirectory of the existing "/shared/app" directory
+Note that the CSS file should be mounted within a subdirectory of the "/shared/app" directory
 (e.g. "/shared/app/custom").  Otherwise, the file will likely fail to be imported by the browser with an
-"incorrect MIME type" error.
+"incorrect MIME type" error. The subdirectory can be changed using `server.staticassets` key of the
+[argocd-cmd-params-cm.yaml](./argocd-cmd-params-cm.yaml) ConfigMap.
 
 ## Developing Style Overlays
 The styles specified in the injected CSS file should be specific to components and classes defined in [argo-ui](https://github.com/argoproj/argo-ui).

docs/operator-manual/server-commands/argocd-server.md

@@ -56,6 +56,7 @@ argocd-server [flags]
       --sentinel stringArray                          Redis sentinel hostname and port (e.g. argocd-redis-ha-announce-0:6379). 
       --sentinelmaster string                         Redis sentinel master group name. (default "master")
       --server string                                 The address and port of the Kubernetes API server
+      --staticassets string                           Directory path that contains additional static assets (default "/shared/app")
       --tls-server-name string                        If provided, this name will be used to validate server certificate. If this is not provided, hostname used to contact the server is used.
       --tlsciphers string                             The list of acceptable ciphers to be used when establishing TLS connections. Use 'list' to list available ciphers. (default "TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384:TLS_RSA_WITH_AES_256_GCM_SHA384")
       --tlsmaxversion string                          The maximum SSL/TLS version that is acceptable (one of: 1.0|1.1|1.2|1.3) (default "1.3")

manifests/base/server/argocd-server-deployment.yaml

@@ -136,6 +136,12 @@ spec:
                 name: argocd-cmd-params-cm
                 key: server.login.attempts.expiration
                 optional: true
+        - name: ARGOCD_SERVER_STATIC_ASSETS
+          valueFrom:
+            configMapKeyRef:
+              name: argocd-cmd-params-cm
+              key: server.staticassets
+              optional: true
         - name: ARGOCD_APP_STATE_CACHE_EXPIRATION
           valueFrom:
               configMapKeyRef:

manifests/ha/install.yaml

@@ -4114,6 +4114,12 @@ spec:
               key: server.login.attempts.expiration
               name: argocd-cmd-params-cm
               optional: true
+        - name: ARGOCD_SERVER_STATIC_ASSETS
+          valueFrom:
+            configMapKeyRef:
+              key: server.staticassets
+              name: argocd-cmd-params-cm
+              optional: true
         - name: ARGOCD_APP_STATE_CACHE_EXPIRATION
           valueFrom:
             configMapKeyRef:

manifests/ha/namespace-install.yaml

@@ -1501,6 +1501,12 @@ spec:
               key: server.login.attempts.expiration
               name: argocd-cmd-params-cm
               optional: true
+        - name: ARGOCD_SERVER_STATIC_ASSETS
+          valueFrom:
+            configMapKeyRef:
+              key: server.staticassets
+              name: argocd-cmd-params-cm
+              optional: true
         - name: ARGOCD_APP_STATE_CACHE_EXPIRATION
           valueFrom:
             configMapKeyRef:

manifests/install.yaml

@@ -3439,6 +3439,12 @@ spec:
               key: server.login.attempts.expiration
               name: argocd-cmd-params-cm
               optional: true
+        - name: ARGOCD_SERVER_STATIC_ASSETS
+          valueFrom:
+            configMapKeyRef:
+              key: server.staticassets
+              name: argocd-cmd-params-cm
+              optional: true
         - name: ARGOCD_APP_STATE_CACHE_EXPIRATION
           valueFrom:
             configMapKeyRef:

manifests/namespace-install.yaml

@@ -826,6 +826,12 @@ spec:
               key: server.login.attempts.expiration
               name: argocd-cmd-params-cm
               optional: true
+        - name: ARGOCD_SERVER_STATIC_ASSETS
+          valueFrom:
+            configMapKeyRef:
+              key: server.staticassets
+              name: argocd-cmd-params-cm
+              optional: true
         - name: ARGOCD_APP_STATE_CACHE_EXPIRATION
           valueFrom:
             configMapKeyRef:

server/server.go

@@ -4,15 +4,13 @@ import (
 	"context"
 	"crypto/tls"
 	"fmt"
-	goio "io"
 	"io/fs"
 	"math"
 	"net"
 	"net/http"
 	"net/url"
 	"os"
 	"os/exec"
-	"path/filepath"
 	"regexp"
 	"strings"
 	gosync "sync"
@@ -134,7 +132,6 @@ var (
 	maxConcurrentLoginRequestsCount = 50
 	replicasCount                   = 1
 	enableGRPCTimeHistogram         = true
-	staticAssets                    = http.FS(&subDirFs{dir: "dist/app", fs: ui.Embedded})
 )
 
 func init() {
@@ -167,12 +164,14 @@ type ArgoCDServer struct {
 	indexDataInit    gosync.Once
 	indexData        []byte
 	indexDataErr     error
+	staticAssets     http.FileSystem
 }
 
 type ArgoCDServerOpts struct {
 	DisableAuth         bool
 	EnableGZip          bool
 	Insecure            bool
+	StaticAssetsDir     string
 	ListenPort          int
 	MetricsPort         int
 	Namespace           string
@@ -236,6 +235,11 @@ func NewServer(ctx context.Context, opts ArgoCDServerOpts) *ArgoCDServer {
 	policyEnf := rbacpolicy.NewRBACPolicyEnforcer(enf, projLister)
 	enf.SetClaimsEnforcerFunc(policyEnf.EnforceClaims)
 
+	var staticFS fs.FS = io.NewSubDirFS("dist/app", ui.Embedded)
+	if opts.StaticAssetsDir != "" {
+		staticFS = io.NewComposableFS(staticFS, os.DirFS(opts.StaticAssetsDir))
+	}
+
 	return &ArgoCDServer{
 		ArgoCDServerOpts: opts,
 		log:              log.NewEntry(log.StandardLogger()),
@@ -248,6 +252,7 @@ func NewServer(ctx context.Context, opts ArgoCDServerOpts) *ArgoCDServer {
 		appLister:        appLister,
 		policyEnforcer:   policyEnf,
 		userStateStorage: userStateStorage,
+		staticAssets:     http.FS(staticFS),
 	}
 }
 
@@ -844,8 +849,8 @@ func (s *ArgoCDServer) getIndexData() ([]byte, error) {
 	return s.indexData, s.indexDataErr
 }
 
-func uiAssetExists(filename string) bool {
-	f, err := staticAssets.Open(strings.Trim(filename, "/"))
+func (server *ArgoCDServer) uiAssetExists(filename string) bool {
+	f, err := server.staticAssets.Open(strings.Trim(filename, "/"))
 	if err != nil {
 		return false
 	}
@@ -868,7 +873,7 @@ func (server *ArgoCDServer) newStaticAssetsHandler() func(http.ResponseWriter, *
 			}
 		}
 
-		fileRequest := r.URL.Path != "/index.html" && uiAssetExists(r.URL.Path)
+		fileRequest := r.URL.Path != "/index.html" && server.uiAssetExists(r.URL.Path)
 
 		// Set X-Frame-Options according to configuration
 		if server.XFrameOptions != "" {
@@ -891,50 +896,13 @@ func (server *ArgoCDServer) newStaticAssetsHandler() func(http.ResponseWriter, *
 			if err != nil {
 				modTime = time.Now()
 			}
-			http.ServeContent(w, r, "index.html", modTime, byteReadSeeker{data: data})
+			http.ServeContent(w, r, "index.html", modTime, io.NewByteReadSeeker(data))
 		} else {
-			http.FileServer(staticAssets).ServeHTTP(w, r)
+			http.FileServer(server.staticAssets).ServeHTTP(w, r)
 		}
 	}
 }
 
-type subDirFs struct {
-	dir string
-	fs  fs.FS
-}
-
-func (s subDirFs) Open(name string) (fs.File, error) {
-	return s.fs.Open(filepath.Join(s.dir, name))
-}
-
-type byteReadSeeker struct {
-	data   []byte
-	offset int64
-}
-
-func (f byteReadSeeker) Read(b []byte) (int, error) {
-	if f.offset >= int64(len(f.data)) {
-		return 0, goio.EOF
-	}
-	n := copy(b, f.data[f.offset:])
-	f.offset += int64(n)
-	return n, nil
-}
-
-func (f byteReadSeeker) Seek(offset int64, whence int) (int64, error) {
-	switch whence {
-	case 1:
-		offset += f.offset
-	case 2:
-		offset += int64(len(f.data))
-	}
-	if offset < 0 || offset > int64(len(f.data)) {
-		return 0, &fs.PathError{Op: "seek", Err: fs.ErrInvalid}
-	}
-	f.offset = offset
-	return offset, nil
-}
-
 type registerFunc func(ctx context.Context, mux *runtime.ServeMux, endpoint string, opts []grpc.DialOption) error
 
 // mustRegisterGWHandler is a convenience function to register a gateway handler

util/io/bytereadseeker.go

@@ -0,0 +1,38 @@
+package io
+
+import (
+	"io"
+	"io/fs"
+)
+
+func NewByteReadSeeker(data []byte) *byteReadSeeker {
+	return &byteReadSeeker{data: data}
+}
+
+type byteReadSeeker struct {
+	data   []byte
+	offset int64
+}
+
+func (f byteReadSeeker) Read(b []byte) (int, error) {
+	if f.offset >= int64(len(f.data)) {
+		return 0, io.EOF
+	}
+	n := copy(b, f.data[f.offset:])
+	f.offset += int64(n)
+	return n, nil
+}
+
+func (f byteReadSeeker) Seek(offset int64, whence int) (int64, error) {
+	switch whence {
+	case 1:
+		offset += f.offset
+	case 2:
+		offset += int64(len(f.data))
+	}
+	if offset < 0 || offset > int64(len(f.data)) {
+		return 0, &fs.PathError{Op: "seek", Err: fs.ErrInvalid}
+	}
+	f.offset = offset
+	return offset, nil
+}

util/io/componsablefs.go

@@ -0,0 +1,23 @@
+package io
+
+import "io/fs"
+
+type composableFS struct {
+	innerFS []fs.FS
+}
+
+// NewComposableFS creates files system that attempts reading file from multiple wrapped file systems
+func NewComposableFS(innerFS ...fs.FS) *composableFS {
+	return &composableFS{innerFS: innerFS}
+}
+
+// Open attempts open file in wrapped file systems and returns first successful
+func (c composableFS) Open(name string) (f fs.File, err error) {
+	for i := range c.innerFS {
+		f, err = c.innerFS[i].Open(name)
+		if err == nil {
+			break
+		}
+	}
+	return
+}

util/io/subdirfs.go

@@ -0,0 +1,20 @@
+package io
+
+import (
+	"io/fs"
+	"path/filepath"
+)
+
+type subDirFs struct {
+	dir string
+	fs  fs.FS
+}
+
+func (s subDirFs) Open(name string) (fs.File, error) {
+	return s.fs.Open(filepath.Join(s.dir, name))
+}
+
+// NewSubDirFS returns file system that represents sub-directory in a wrapped file system
+func NewSubDirFS(dir string, fs fs.FS) *subDirFs {
+	return &subDirFs{dir: dir, fs: fs}
+}