fix: Inject current environment variables to spawn process (#218)

Add current process environment variables to spawned process, inherit `stdio` for spawned process, append `.cmd` if windows

Author: tbarlow12

src/services/offlineService.test.ts

@@ -7,10 +7,7 @@ import { MockFactory } from "../test/mockFactory";
 import { OfflineService } from "./offlineService";
 
 describe("Offline Service", () => {
-
-  const mySpawn = mockSpawn();
-  require("child_process").spawn = mySpawn;
-  mySpawn.setDefault(mySpawn.simple(0, "Exit code"));
+  let mySpawn;
 
   function createService(sls?: Serverless): OfflineService {
     return new OfflineService(
@@ -21,12 +18,16 @@ describe("Offline Service", () => {
 
   beforeEach(() => {
     // Mocking the file system so that files are not created in project directory
-    mockFs({})
+    mockFs({});
+
+    mySpawn = mockSpawn();
+    require("child_process").spawn = mySpawn;
+    mySpawn.setDefault(mySpawn.simple(0, "Exit code"));
   });
 
   afterEach(() => {
     mockFs.restore();
-  })
+  });
 
   it("builds required files for offline execution", async () => {
     const sls = MockFactory.createTestServerless();
@@ -113,7 +114,12 @@ describe("Offline Service", () => {
     rmdirSpy.mockRestore();
   });
 
-  it("instructs users how to run locally", async () => {
+  it("calls func host start on Mac OS", async () => {
+    Object.defineProperty(process, "platform", {
+      value: "darwin",
+      writable: true,
+    });
+
     const sls = MockFactory.createTestServerless();
     const service = createService(sls);
     await service.start();
@@ -123,4 +129,20 @@ describe("Offline Service", () => {
     expect(call.command).toEqual("func");
     expect(call.args).toEqual(["host", "start"]);
   });
+
+  it("calls func host start on windows", async () => {
+    Object.defineProperty(process, "platform", {
+      value: "win32",
+      writable: true,
+    });
+
+    const sls = MockFactory.createTestServerless();
+    const service = createService(sls);
+    await service.start();
+    const calls = mySpawn.calls;
+    expect(calls).toHaveLength(1);
+    const call = calls[0];
+    expect(call.command).toEqual("func.cmd");
+    expect(call.args).toEqual(["host", "start"]);
+  });
 });

src/services/offlineService.ts

@@ -1,4 +1,4 @@
-import { spawn } from "child_process";
+import { spawn, SpawnOptions } from "child_process";
 import fs from "fs";
 import Serverless from "serverless";
 import configConstants from "../config";
@@ -29,7 +29,7 @@ export class OfflineService extends BaseService {
     await this.packageService.createBindings();
     const filenames = Object.keys(this.localFiles);
     for (const filename of filenames) {
-      if (!fs.existsSync(filename)){
+      if (!fs.existsSync(filename)) {
         fs.writeFileSync(
           filename,
           this.localFiles[filename]
@@ -44,7 +44,7 @@ export class OfflineService extends BaseService {
     await this.packageService.cleanUp();
     const filenames = Object.keys(this.localFiles);
     for (const filename of filenames) {
-      if (fs.existsSync(filename)){
+      if (fs.existsSync(filename)) {
         this.log(`Removing file '${filename}'`);
         fs.unlinkSync(filename)
       }
@@ -62,59 +62,30 @@ export class OfflineService extends BaseService {
   /**
    * Spawn a Node child process with predefined environment variables
    * @param command CLI Command - NO ARGS
-   * @param args Array of arguments for CLI command
-   * @param env Additional environment variables to be set in addition to
-   * predefined variables in `serverless.yml`
+   * @param spawnArgs Array of arguments for CLI command
    */
-  private spawn(command: string, args?: string[], env?: any): Promise<void> {
-    env = {
+  private spawn(command: string, spawnArgs?: string[]): Promise<void> {
+    if (process.platform === "win32") {
+      command += ".cmd";
+    }
+
+    const env = {
+      // Inherit environment from current process, most importantly, the PATH
+      ...process.env,
+      // Environment variables from serverless config are king
       ...this.serverless.service.provider["environment"],
-      ...env
     }
-    this.log(`Spawning process '${command} ${args.join(" ")}'`);
+    this.log(`Spawning process '${command} ${spawnArgs.join(" ")}'`);
     return new Promise((resolve, reject) => {
-      const childProcess = spawn(command, args, {env});
-
-      childProcess.stdout.on("data", (data) => {
-        this.log(data, {
-          color: configConstants.funcConsoleColor,
-        }, command);
-      });
-
-      childProcess.stderr.on("data", (data) => {
-        this.log(data, {
-          color: "red",
-        }, command);
-      })
-
-      childProcess.on("message", (message) => {
-        this.log(message, {
-          color: configConstants.funcConsoleColor,
-        }, command);
-      });
-
-      childProcess.on("error", (err) => {
-        this.log(`${err}`, {
-          color: "red"
-        }, command);
-        reject(err);
-      });
+      const spawnOptions: SpawnOptions = { env, stdio: "inherit" };
+      const childProcess = spawn(command, spawnArgs, spawnOptions);
 
       childProcess.on("exit", (code) => {
-        this.log(`Exited with code: ${code}`, {
-          color: (code === 0) ? "green" : "red",
-        }, command);
-      });
-
-      childProcess.on("close", (code) => {
-        this.log(`Closed with code: ${code}`, {
-          color: (code === 0) ? "green" : "red",
-        }, command);
-        resolve();
-      });
-
-      childProcess.on("disconnect", () => {
-        this.log("Process disconnected");
+        if (code === 0) {
+          resolve();
+        } else {
+          reject();
+        }
       });
     });
   }