feat(cli): make url optional for login command (#10925) (#12466)

Allow `coder login` to log into existing deployment if available.

Update help and error messages to indicate that `coder login` is
available as a command.

Fixes #10925
Fixes #9551

cli/login.go

@@ -136,16 +136,28 @@ func (r *RootCmd) login() *clibase.Cmd {
 		useTokenForSession bool
 	)
 	cmd := &clibase.Cmd{
-		Use:        "login <url>",
+		Use:        "login [<url>]",
 		Short:      "Authenticate with Coder deployment",
 		Middleware: clibase.RequireRangeArgs(0, 1),
 		Handler: func(inv *clibase.Invocation) error {
 			ctx := inv.Context()
 			rawURL := ""
+			var urlSource string
+
 			if len(inv.Args) == 0 {
 				rawURL = r.clientURL.String()
+				urlSource = "flag"
+				if rawURL != "" && rawURL == inv.Environ.Get(envURL) {
+					urlSource = "environment"
+				}
 			} else {
 				rawURL = inv.Args[0]
+				urlSource = "argument"
+			}
+
+			if url, err := r.createConfig().URL().Read(); rawURL == "" && err == nil {
+				urlSource = "config"
+				rawURL = url
 			}
 
 			if rawURL == "" {
@@ -187,6 +199,9 @@ func (r *RootCmd) login() *clibase.Cmd {
 			if err != nil {
 				return xerrors.Errorf("Failed to check server %q for first user, is the URL correct and is coder accessible from your browser? Error - has initial user: %w", serverURL.String(), err)
 			}
+
+			_, _ = fmt.Fprintf(inv.Stdout, "Attempting to authenticate with %s URL: '%s'\n", urlSource, serverURL)
+
 			if !hasFirstUser {
 				_, _ = fmt.Fprintf(inv.Stdout, Caret+"Your Coder deployment hasn't been set up!\n")
 

cli/login_test.go

@@ -116,6 +116,7 @@ func TestLogin(t *testing.T) {
 
 		clitest.Start(t, inv)
 
+		pty.ExpectMatch(fmt.Sprintf("Attempting to authenticate with flag URL: '%s'", client.URL.String()))
 		matches := []string{
 			"first user?", "yes",
 			"username", "testuser",
@@ -205,6 +206,7 @@ func TestLogin(t *testing.T) {
 			assert.NoError(t, err)
 		}()
 
+		pty.ExpectMatch(fmt.Sprintf("Attempting to authenticate with argument URL: '%s'", client.URL.String()))
 		pty.ExpectMatch("Paste your token here:")
 		pty.WriteLine(client.SessionToken())
 		if runtime.GOOS != "windows" {
@@ -215,6 +217,52 @@ func TestLogin(t *testing.T) {
 		<-doneChan
 	})
 
+	t.Run("ExistingUserURLSavedInConfig", func(t *testing.T) {
+		t.Parallel()
+		client := coderdtest.New(t, nil)
+		url := client.URL.String()
+		coderdtest.CreateFirstUser(t, client)
+
+		inv, root := clitest.New(t, "login", "--no-open")
+		clitest.SetupConfig(t, client, root)
+
+		doneChan := make(chan struct{})
+		pty := ptytest.New(t).Attach(inv)
+		go func() {
+			defer close(doneChan)
+			err := inv.Run()
+			assert.NoError(t, err)
+		}()
+
+		pty.ExpectMatch(fmt.Sprintf("Attempting to authenticate with config URL: '%s'", url))
+		pty.ExpectMatch("Paste your token here:")
+		pty.WriteLine(client.SessionToken())
+		<-doneChan
+	})
+
+	t.Run("ExistingUserURLSavedInEnv", func(t *testing.T) {
+		t.Parallel()
+		client := coderdtest.New(t, nil)
+		url := client.URL.String()
+		coderdtest.CreateFirstUser(t, client)
+
+		inv, _ := clitest.New(t, "login", "--no-open")
+		inv.Environ.Set("CODER_URL", url)
+
+		doneChan := make(chan struct{})
+		pty := ptytest.New(t).Attach(inv)
+		go func() {
+			defer close(doneChan)
+			err := inv.Run()
+			assert.NoError(t, err)
+		}()
+
+		pty.ExpectMatch(fmt.Sprintf("Attempting to authenticate with environment URL: '%s'", url))
+		pty.ExpectMatch("Paste your token here:")
+		pty.WriteLine(client.SessionToken())
+		<-doneChan
+	})
+
 	t.Run("ExistingUserInvalidTokenTTY", func(t *testing.T) {
 		t.Parallel()
 		client := coderdtest.New(t, nil)

cli/logout_test.go

@@ -119,7 +119,7 @@ func TestLogout(t *testing.T) {
 		go func() {
 			defer close(logoutChan)
 			err = logout.Run()
-			assert.ErrorContains(t, err, "You are not logged in. Try logging in using 'coder login <url>'.")
+			assert.ErrorContains(t, err, "You are not logged in. Try logging in using 'coder login'.")
 		}()
 
 		<-logoutChan

cli/root.go

@@ -65,7 +65,9 @@ const (
 	varVerbose            = "verbose"
 	varOrganizationSelect = "organization"
 	varDisableDirect      = "disable-direct-connections"
-	notLoggedInMessage    = "You are not logged in. Try logging in using 'coder login <url>'."
+
+	notLoggedInMessage         = "You are not logged in. Try logging in using 'coder login <url>'."
+	notLoggedInURLSavedMessage = "You are not logged in. Try logging in using 'coder login'."
 
 	envNoVersionCheck   = "CODER_NO_VERSION_WARNING"
 	envNoFeatureWarning = "CODER_NO_FEATURE_WARNING"
@@ -77,7 +79,10 @@ const (
 	envURL            = "CODER_URL"
 )
 
-var errUnauthenticated = xerrors.New(notLoggedInMessage)
+var (
+	errUnauthenticated         = xerrors.New(notLoggedInMessage)
+	errUnauthenticatedURLSaved = xerrors.New(notLoggedInURLSavedMessage)
+)
 
 func (r *RootCmd) Core() []*clibase.Cmd {
 	// Please re-sort this list alphabetically if you change it!
@@ -574,7 +579,7 @@ func (r *RootCmd) initClientInternal(client *codersdk.Client, allowTokenMissing
 				// If the configuration files are absent, the user is logged out
 				if os.IsNotExist(err) {
 					if !allowTokenMissing {
-						return errUnauthenticated
+						return errUnauthenticatedURLSaved
 					}
 				} else if err != nil {
 					return err

cli/testdata/coder_login_--help.golden

@@ -1,7 +1,7 @@
 coder v0.0.0-devel
 
 USAGE:
-  coder login [flags] <url>
+  coder login [flags] [<url>]
 
   Authenticate with Coder deployment
 

docs/cli/login.md

@@ -7,7 +7,7 @@ Authenticate with Coder deployment
 ## Usage
 
 ```console
-coder login [flags] <url>
+coder login [flags] [<url>]
 ```
 
 ## Options