Add templated_url support

action.yml

@@ -81,6 +81,10 @@ inputs:
     description: "Path to a local bash script (relative to app_path) executed inline over SSH on the instance before docker compose"
     required: false
     default: ""
+  templated_url:
+    description: "Template for the preview URL displayed in PR comments and outputs (use {{ pullpreview_url }} as placeholder, e.g. {{ pullpreview_url }}/custom/path?key=value)"
+    required: false
+    default: ""
   ttl:
     description: "Maximum time to live for deployments (e.g. 10h, 5d, infinite)"
     required: false
@@ -168,7 +172,8 @@ runs:
           --registries "${{ inputs.registries }}" \
           --proxy-tls "${{ inputs.proxy_tls }}" \
           --pre-script "${{ inputs.pre_script }}" \
-          --ttl "${{ inputs.ttl }}"
+          --ttl "${{ inputs.ttl }}" \
+          --templated-url "${{ inputs.templated_url }}"
 
         if grep -q '^url=' "${GITHUB_OUTPUT}"; then
           echo "live=true" >> "${GITHUB_OUTPUT}"

cmd/pullpreview/main.go

@@ -116,6 +116,7 @@ func runGithubSync(ctx context.Context, args []string, logger *pullpreview.Logge
 	label := fs.String("label", "pullpreview", "Label to use for triggering preview deployments")
 	deploymentVariant := fs.String("deployment-variant", "", "Deployment variant (4 chars max)")
 	ttl := fs.String("ttl", "infinite", "Maximum time to live for deployments (e.g. 10h, 5d, infinite)")
+	templatedURL := fs.String("templated-url", "", "Template for the preview URL (use {{ pullpreview_url }} as placeholder)")
 	commonFlags := registerCommonFlags(fs)
 	leadingPath, parseArgs := splitLeadingPositional(args)
 	fs.Parse(parseArgs)
@@ -137,6 +138,7 @@ func runGithubSync(ctx context.Context, args []string, logger *pullpreview.Logge
 		Label:             *label,
 		DeploymentVariant: *deploymentVariant,
 		TTL:               *ttl,
+		TemplatedURL:      *templatedURL,
 		Context:           ctx,
 		Common:            commonOptions,
 	}

internal/pullpreview/github_sync.go

@@ -486,8 +486,10 @@ func (g *GithubSync) Sync() error {
 			return err
 		}
 		if upInstance != nil {
-			_ = g.updateGitHubStatus(statusDeployed, upInstance.URL())
-			g.writeStepSummary(statusDeployed, action, upInstance.URL(), upInstance)
+			displayURL := g.applyTemplatedURL(upInstance.URL())
+			_ = g.updateGitHubStatus(statusDeployed, displayURL)
+			g.writeStepSummary(statusDeployed, action, displayURL, upInstance)
+			g.writeTemplatedURLOutput(displayURL)
 		}
 	}
 	return nil
@@ -722,6 +724,30 @@ func (g *GithubSync) writeStepSummary(status deploymentStatus, action actionType
 	}
 }
 
+func (g *GithubSync) applyTemplatedURL(rawURL string) string {
+	tpl := strings.TrimSpace(g.opts.TemplatedURL)
+	if tpl == "" {
+		return rawURL
+	}
+	return strings.ReplaceAll(tpl, "{{ pullpreview_url }}", rawURL)
+}
+
+func (g *GithubSync) writeTemplatedURLOutput(displayURL string) {
+	if strings.TrimSpace(g.opts.TemplatedURL) == "" {
+		return
+	}
+	path := os.Getenv("GITHUB_OUTPUT")
+	if path == "" {
+		return
+	}
+	f, err := os.OpenFile(path, os.O_APPEND|os.O_WRONLY, 0644)
+	if err != nil {
+		return
+	}
+	defer f.Close()
+	fmt.Fprintf(f, "url=%s\n", displayURL)
+}
+
 func (g *GithubSync) workflowRunURL() string {
 	server := strings.TrimSuffix(os.Getenv("GITHUB_SERVER_URL"), "/")
 	runID := strings.TrimSpace(os.Getenv("GITHUB_RUN_ID"))

internal/pullpreview/github_sync_test.go

@@ -503,6 +503,69 @@ func TestRenderStepSummaryForDeployedState(t *testing.T) {
 	}
 }
 
+func TestApplyTemplatedURL(t *testing.T) {
+	event := loadFixtureEvent(t, "github_event_labeled.json")
+	tests := []struct {
+		name         string
+		templatedURL string
+		rawURL       string
+		want         string
+	}{
+		{
+			name:         "empty template returns raw URL",
+			templatedURL: "",
+			rawURL:       "http://pr-1-ip-1-2-3-4.my.preview.run:80",
+			want:         "http://pr-1-ip-1-2-3-4.my.preview.run:80",
+		},
+		{
+			name:         "template with custom path",
+			templatedURL: "{{ pullpreview_url }}/custom/path?key=value",
+			rawURL:       "http://pr-1-ip-1-2-3-4.my.preview.run:80",
+			want:         "http://pr-1-ip-1-2-3-4.my.preview.run:80/custom/path?key=value",
+		},
+		{
+			name:         "template with encoded params",
+			templatedURL: "{{ pullpreview_url }}/abc?redirectTo=def%2Fghi",
+			rawURL:       "https://pr-1-ip-1-2-3-4.my.preview.run:443",
+			want:         "https://pr-1-ip-1-2-3-4.my.preview.run:443/abc?redirectTo=def%2Fghi",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			sync := newSync(event, GithubSyncOptions{Label: "pullpreview", TemplatedURL: tt.templatedURL, Common: CommonOptions{}}, &fakeGitHub{}, fakeProvider{running: true})
+			got := sync.applyTemplatedURL(tt.rawURL)
+			if got != tt.want {
+				t.Fatalf("applyTemplatedURL()=%q, want %q", got, tt.want)
+			}
+		})
+	}
+}
+
+func TestSyncLabeledWithTemplatedURLUsesTemplateInComment(t *testing.T) {
+	t.Setenv("PULLPREVIEW_TEST", "1")
+	t.Setenv("GITHUB_SERVER_URL", "https://github.com")
+	t.Setenv("GITHUB_RUN_ID", "12345")
+	t.Setenv("GITHUB_STEP_SUMMARY", filepath.Join(t.TempDir(), "summary.md"))
+	event := loadFixtureEvent(t, "github_event_labeled.json")
+	client := &fakeGitHub{latestSHA: event.PullRequest.Head.SHA}
+	sync := newSync(event, GithubSyncOptions{
+		Label:        "pullpreview",
+		TemplatedURL: "{{ pullpreview_url }}/app?lang=en",
+		Common:       CommonOptions{},
+	}, client, fakeProvider{running: true})
+
+	if err := sync.Sync(); err != nil {
+		t.Fatalf("Sync() returned error: %v", err)
+	}
+	if len(client.updatedComments) == 0 {
+		t.Fatalf("expected PR comment update on deployed state")
+	}
+	lastComment := client.updatedComments[len(client.updatedComments)-1]
+	if !strings.Contains(lastComment, "/app?lang=en") {
+		t.Fatalf("expected templated URL with custom path in PR comment, got %q", lastComment)
+	}
+}
+
 func TestRunGithubSyncFromEnvironmentRunsDownForBranchPush(t *testing.T) {
 	t.Setenv("PULLPREVIEW_TEST", "1")
 	event := loadFixtureEvent(t, "github_event_push_solo_organization.json")

internal/pullpreview/types.go

@@ -114,6 +114,7 @@ type GithubSyncOptions struct {
 	Label             string
 	DeploymentVariant string
 	TTL               string
+	TemplatedURL      string
 	Context           context.Context
 	Common            CommonOptions
 }