Project harness for Typescript (#337)

## What was changed
Adds `typescript/harness/` package, effectively a port of the same
Python harness (`python/harness`).

`typescript/harness` is a standalone Typescript package that supports
the same harness semantics, structure, and API as the existing Python
harness. The test suite (`typescript/harness/tests`) similarly mimics
the existing Python harness test suite.

A couple changes that are Typescript-specific:
- the `workers/typescript` package now uses `npm workspaces`. This is so
that we can enforce the same `temporalio` version between the test and
the harness, which are separate Typescript packages.
- `protogen.js` and `grpc-helpers.ts` exist to generate protobuf types
and grpc helpers that the Typescript harness consumes (In contrast,
Python commits the generated proto. The Typescript kitchensink protos
were already generated on the fly, I stuck with that pattern for the
harness protos)

## Why?
- load testing ergonomics / DX
- Language parity

Author: THardy98

.dockerignore

@@ -0,0 +1,5 @@
+**/node_modules
+workers/typescript/lib
+workers/typescript/tsconfig.tsbuildinfo
+workers/typescript/harness/dist*
+workers/typescript/harness/src/generated

.gitignore

@@ -21,6 +21,9 @@ omes.sln
 workers/dotnet/Temporalio.Omes.temp.csproj
 
 workers/python/**/__pycache__/
+workers/typescript/harness/dist/
+workers/typescript/harness/dist-test/
+workers/typescript/harness/src/generated/
 workers/*/omes-temp-*/
 workers/*/prepared/
 workers/**/project-build-*/

cmd/dev/lint_and_format.go

@@ -174,6 +174,21 @@ func lintAndFormatTypescriptWorker(ctx context.Context, workerDir string) error
 		return err
 	}
 
+	fmt.Println("Formatting TypeScript harness...")
+	if err := runCommandInDir(ctx, workerDir, "npm", "run", "-w", "@temporalio/omes-project-harness", "format"); err != nil {
+		return err
+	}
+
+	fmt.Println("Linting TypeScript harness...")
+	if err := runCommandInDir(ctx, workerDir, "npm", "run", "-w", "@temporalio/omes-project-harness", "lint"); err != nil {
+		return err
+	}
+
+	fmt.Println("Compiling TypeScript harness...")
+	if err := runCommandInDir(ctx, workerDir, "npm", "run", "-w", "@temporalio/omes-project-harness", "typecheck"); err != nil {
+		return err
+	}
+
 	fmt.Println("✅ TypeScript lint-and-format completed successfully!")
 	return nil
 }

cmd/dev/test.go

@@ -87,6 +87,11 @@ func runTestWorker(ctx context.Context, language string) error {
 			return err
 		}
 	}
+	if language == "typescript" {
+		if err := runTypeScriptHarnessTests(ctx, repoDir); err != nil {
+			return err
+		}
+	}
 	return testWorkerLocally(ctx, repoDir, language, sdkVersion)
 }
 
@@ -110,6 +115,16 @@ func runDotnetHarnessTests(ctx context.Context, repoDir string) error {
 	return nil
 }
 
+func runTypeScriptHarnessTests(ctx context.Context, repoDir string) error {
+	workerDir := filepath.Join(repoDir, "workers", "typescript")
+	fmt.Println("Running TypeScript harness tests...")
+	if err := runCommandInDir(ctx, workerDir, "npm", "run", "-w", "@temporalio/omes-project-harness", "test"); err != nil {
+		return fmt.Errorf("failed TypeScript harness tests: %w", err)
+	}
+	fmt.Println("✅ TypeScript harness tests completed successfully!")
+	return nil
+}
+
 func testWorkerLocally(ctx context.Context, repoDir, language, sdkVersion string) error {
 	args := []string{
 		"go", "run", "./cmd", "run-scenario-with-worker",

dockerfiles/typescript.Dockerfile

@@ -51,11 +51,8 @@ COPY workers/typescript ./workers/typescript
 # Install pnpm (sdkbuild uses pnpm to build typescript programs)
 RUN npm install -g pnpm
 
-# Build typescript proto files
-# hadolint ignore=DL3003
-RUN cd workers/typescript && npm install && npm run proto-gen
-
-# Build the worker
+# prepare-worker builds the TypeScript workspace itself: it installs npm deps,
+# runs the root build, and generates the prepared sdkbuild package.
 RUN CGO_ENABLED=0 ./temporal-omes prepare-worker --language ts --dir-name prepared --version "$SDK_VERSION"
 
 # Copy the CLI and prepared feature to a "run" container.

workers/build.go

@@ -2,6 +2,7 @@ package workers
 
 import (
 	"context"
+	"encoding/json"
 	"fmt"
 	"html"
 	"io"
@@ -149,20 +150,23 @@ func (b *Builder) buildTypeScript(ctx context.Context, baseDir string) (sdkbuild
 	// If version not provided, try to read it from package.json
 	version := b.SdkOptions.Version
 	if version == "" {
-		b, err := os.ReadFile(filepath.Join(baseDir, "package.json"))
+		packageJSON, err := os.ReadFile(filepath.Join(baseDir, "package.json"))
 		if err != nil {
 			return nil, fmt.Errorf("failed reading package.json: %w", err)
 		}
-		for line := range strings.SplitSeq(string(b), "\n") {
-			line = strings.TrimSpace(line)
-			if strings.HasPrefix(line, "\"temporalio:\"") || strings.HasPrefix(line, "\"@temporalio/") {
-				split := strings.Split(line, "\"")
-				version = split[len(split)-2]
-				break
-			}
+
+		var pkg struct {
+			Dependencies map[string]string `json:"dependencies"`
+		}
+		if err := json.Unmarshal(packageJSON, &pkg); err != nil {
+			return nil, fmt.Errorf("failed parsing package.json: %w", err)
 		}
+		// Pick a single temporal dependency, assumption is that the version for
+		// other temporal dependency versions will match.
+		const temporalTypeScriptSDKPackage = "@temporalio/client"
+		version = pkg.Dependencies[temporalTypeScriptSDKPackage]
 		if version == "" {
-			return nil, fmt.Errorf("version not found in package.json")
+			return nil, fmt.Errorf("version not found in package.json for %s", temporalTypeScriptSDKPackage)
 		}
 	}
 
@@ -191,7 +195,8 @@ func (b *Builder) buildTypeScript(ctx context.Context, baseDir string) (sdkbuild
 		ApplyToCommand: nil,
 		Includes:       []string{"../src/**/*.ts", "../src/protos/json-module.js", "../src/protos/root.js"},
 		MoreDependencies: map[string]string{
-			"winston": "^3.11.0",
+			"@temporalio/omes-project-harness": "file:../harness",
+			"winston":                          "^3.11.0",
 		},
 		Stdout: b.stdout,
 		Stderr: b.stderr,

workers/run.go

@@ -130,8 +130,8 @@ func (r *Runner) Run(ctx context.Context, baseDir string) error {
 		// The dotnet harness uses explicit subcommands like the Python harness.
 		args = append(args, "worker")
 	} else if r.SdkOptions.Language == clioptions.LangTypeScript {
-		// Node also needs module
-		args = append(args, "./tslib/omes.js")
+		// Node also needs module before the harness subcommand.
+		args = append(args, "./tslib/omes.js", "worker")
 	}
 	args = append(args, "--task-queue", r.TaskQueueName)
 	if r.TaskQueueIndexSuffixEnd > 0 {

workers/typescript/.prettierignore

@@ -1,3 +1,4 @@
 lib
 src/protos/
+harness/
 omes-temp-*

workers/typescript/harness/.prettierignore

@@ -0,0 +1,3 @@
+dist/
+dist-test/
+src/generated/

workers/typescript/harness/eslint.config.mjs

@@ -0,0 +1,39 @@
+import js from '@eslint/js';
+import tseslint from 'typescript-eslint';
+import prettierConfig from 'eslint-config-prettier';
+
+export default tseslint.config(
+  {
+    ignores: [
+      '**/node_modules/**',
+      '**/dist/**',
+      '**/dist-test/**',
+      '**/*.js',
+      '**/*.mjs',
+      '**/*.cjs',
+      'src/generated/**',
+      'protogen.js',
+    ],
+  },
+  {
+    files: ['src/**/*.ts', 'tests/**/*.ts'],
+    extends: [js.configs.recommended, ...tseslint.configs.recommended, prettierConfig],
+    languageOptions: {
+      parserOptions: { project: ['./tsconfig.json', './tsconfig.test.json'] },
+    },
+    rules: {
+      '@typescript-eslint/no-deprecated': 'warn',
+      '@typescript-eslint/no-explicit-any': 'off',
+      '@typescript-eslint/no-floating-promises': 'error',
+      '@typescript-eslint/no-unused-vars': [
+        'warn',
+        {
+          argsIgnorePattern: '^_',
+          caughtErrorsIgnorePattern: '^_',
+          varsIgnorePattern: '^_',
+        },
+      ],
+      'object-shorthand': ['error', 'always'],
+    },
+  },
+);