Add an example of Dockerized NodeJS build in TypeScript

This should help address #13.

.circleci/config.yml

@@ -34,3 +34,9 @@ jobs:
             cd tests/examples/react-app
             yarn install
             bazel build ...
+      - run:
+          name: Build Dockerized TypeScript Node example
+          command: |
+            cd examples/node-typescript-app
+            bazel build //...
+            bazel run //services/my-service:image

WORKSPACE

@@ -9,3 +9,9 @@ git_repository(
 load("@build_bazel_rules_nodejs//:defs.bzl", "node_repositories")
 
 node_repositories(package_json = [])
+
+# See https://github.com/bazelbuild/bazel/issues/2460#issuecomment-362284757
+local_repository(
+  name = "ignore_examples",
+  path = "./examples",
+)

examples/WORKSPACE

@@ -0,0 +1 @@
+# See https://github.com/bazelbuild/bazel/issues/2460#issuecomment-362284757

examples/node-typescript-app/BUILD.bazel

@@ -0,0 +1,11 @@
+package(default_visibility = ["//visibility:public"])
+
+exports_files(["tsconfig.json"])
+
+load("@bazel_javascript//:defs.bzl", "npm_packages")
+
+npm_packages(
+  name = "packages",
+  package_json = ":package.json",
+  yarn_lock = ":yarn.lock",
+)

examples/node-typescript-app/README.md

@@ -0,0 +1,12 @@
+# Dockerized Node server in TypeScript
+
+This directory contains a Docker image with a Node server built from TypeScript with Bazel.
+
+A few things worth noting:
+- `tsconfig.json` must have `allowSyntheticDefaultImports` set to `false`
+- We generate source maps and run `node -r source-map-support/register` so error stack traces
+  match the TypeScript source.
+- We don't use any TypeScript aliases, because they will remain as such and confuse Node. This
+  could be fixed by re-introducing preprocessing which was removed in [d81c2e3](https://github.com/zenclabs/bazel-javascript/commit/d81c2e3f130fe09348952963d58fe560a416e5da).
+- We use a symlinked directory to ensure `node_modules` is available to Node.
+- `WORKSPACE` needs to be edited to include the remote, not local version of `bazel_javascript`.

examples/node-typescript-app/WORKSPACE

@@ -0,0 +1,49 @@
+# Note: We use a local version of bazel-javascript rules here.
+#
+# You should remove this and use the remote version below instead.
+local_repository(
+  name = "bazel_javascript",
+  path = "../..",
+)
+
+# git_repository(
+#     name = "bazel_javascript",
+#     remote = "https://github.com/zenclabs/bazel-javascript.git",
+#     tag = <use the latest tag>,
+# )
+
+git_repository(
+    name = "build_bazel_rules_nodejs",
+    remote = "https://github.com/bazelbuild/rules_nodejs.git",
+    tag = "0.10.0",
+)
+
+load("@build_bazel_rules_nodejs//:defs.bzl", "node_repositories")
+
+node_repositories(
+    package_json = [],
+)
+
+load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
+
+http_archive(
+    name = "io_bazel_rules_docker",
+    sha256 = "5d64414477ffe87b16e248986c0731aee821ea3d626121cfeeec4ef7096812ca",
+    strip_prefix = "rules_docker-0.5.0",
+    urls = ["https://github.com/bazelbuild/rules_docker/archive/v0.5.0.tar.gz"],
+)
+
+load(
+    "@io_bazel_rules_docker//container:container.bzl",
+    "container_pull",
+    container_repositories = "repositories",
+)
+
+container_repositories()
+
+container_pull(
+    name = "node_alpine_image",
+    registry = "index.docker.io",
+    repository = "library/node",
+    tag = "8.11.3-alpine",
+)

examples/node-typescript-app/libs/shared-package/BUILD.bazel

@@ -0,0 +1,9 @@
+package(default_visibility = ["//visibility:public"])
+
+load("@bazel_javascript//:defs.bzl", "ts_library")
+
+ts_library(
+  name = "shared-package",
+  srcs = glob(["**/*.ts"]),
+  tsconfig = "//:tsconfig.json",
+)

examples/node-typescript-app/libs/shared-package/greeter.ts

@@ -0,0 +1,3 @@
+export function greet(name: string): string {
+  return `Hello, ${name}`;
+}

examples/node-typescript-app/package.json

@@ -0,0 +1,10 @@
+{
+  "name": "node-typescript-app",
+  "version": "1.0.0",
+  "dependencies": {
+    "@types/koa": "^2.0.46",
+    "@types/node": "^10.7.1",
+    "koa": "^2.5.2",
+    "source-map-support": "^0.5.9"
+  }
+}

examples/node-typescript-app/services/base-image/BUILD.bazel

@@ -0,0 +1,11 @@
+package(default_visibility = ["//visibility:public"])
+
+load("@io_bazel_rules_docker//container:container.bzl", "container_image", "container_push")
+
+## The Backend Base Image
+container_image(
+  name = "service",
+  base = "@node_alpine_image//image:image",
+  stamp = True,
+  workdir = "/app",
+)

examples/node-typescript-app/services/my-service/BUILD.bazel

@@ -0,0 +1,37 @@
+package(default_visibility = ["//visibility:public"])
+
+load("@io_bazel_rules_docker//container:container.bzl", "container_image", "container_push")
+
+container_image(
+  name = "image",
+  base = "//services/base-image:service",
+  data_path = ".",
+  directory = "/app",
+  files = [
+    "//:packages",
+    "//services/my-service/server:server_compiled",
+  ],
+  symlinks = {
+    "/app/node_modules": "/app/packages_installed_dir/node_modules",
+  },
+  cmd = [
+    "node",
+    "-r",
+    "source-map-support/register",
+    "server/server_compiled/services/my-service/server/server.js",
+  ],
+  ports = [
+    "3000",
+  ],
+  stamp = True,
+)
+
+container_push(
+  name = "publish",
+  format = "Docker",
+  image = ":image",
+  registry = "my.repo.com",
+  repository = "my-service",
+  stamp = True,
+  tag = "{BUILD_USER}",
+)

examples/node-typescript-app/services/my-service/server/BUILD.bazel

@@ -0,0 +1,13 @@
+package(default_visibility = ["//visibility:public"])
+
+load("@bazel_javascript//:defs.bzl", "ts_library")
+
+ts_library(
+  name = "server",
+  srcs = glob(["**/*.ts"]),
+  tsconfig = "//:tsconfig.json",
+  deps = [
+    "//:packages",
+    "//libs/shared-package",
+  ],
+)

examples/node-typescript-app/services/my-service/server/server.ts

@@ -0,0 +1,15 @@
+import * as Koa from "koa";
+import { greet } from "../../../libs/shared-package/greeter";
+
+const app = new Koa();
+
+app.use(async ctx => {
+  ctx.body = greet("World");
+  // Just for fun, add a small chance of crashing. This allows us to check whether stack
+  // traces are readable.
+  if (Math.random() < 0.1) {
+    throw new Error("Random crash.");
+  }
+});
+
+app.listen(3000, () => console.log("Server is ready."));

examples/node-typescript-app/tsconfig.json

@@ -0,0 +1,18 @@
+{
+  "compilerOptions": {
+    "target": "es2015",
+    "module": "commonjs",
+    "moduleResolution": "node",
+    "declaration": true,
+    "sourceMap": true,
+    "strict": true,
+    "noImplicitAny": true,
+    "strictNullChecks": true,
+    "strictFunctionTypes": true,
+    "strictPropertyInitialization": true,
+    "noImplicitThis": true,
+    "alwaysStrict": true,
+    "jsx": "react",
+    "allowSyntheticDefaultImports": false
+  }
+}