Fixes retrieving process name on Azure Functions. Closes pnp#4229

Author: waldekmastykarz

src/utils/pid.spec.ts

@@ -18,7 +18,7 @@ describe('utils/pid', () => {
   afterEach(() => {
     sinonUtil.restore([
       os.platform,
-      child_process.execSync,
+      child_process.spawnSync,
       fs.existsSync,
       fs.readFileSync
     ]);
@@ -33,18 +33,37 @@ describe('utils/pid', () => {
 
   it('retrieves process name on Windows', () => {
     sinon.stub(os, 'platform').callsFake(() => 'win32');
-    sinon.stub(child_process, 'execSync').callsFake(() => 'pwsh');
+    sinon.stub(child_process, 'spawnSync').callsFake(() => {
+      return {
+        stdout: 'pwsh'
+      } as any;
+    });
 
     assert.strictEqual(pid.getProcessName(123), 'pwsh');
   });
 
   it('retrieves process name on macOS', () => {
     sinon.stub(os, 'platform').callsFake(() => 'darwin');
-    sinon.stub(child_process, 'execSync').callsFake(() => '/bin/bash');
+    sinon.stub(child_process, 'spawnSync').callsFake(() => {
+      return {
+        stdout: '/bin/bash'
+      } as any;
+    });
 
     assert.strictEqual(pid.getProcessName(123), '/bin/bash');
   });
 
+  it('retrieves undefined on macOS when retrieving the process name failed', () => {
+    sinon.stub(os, 'platform').callsFake(() => 'darwin');
+    sinon.stub(child_process, 'spawnSync').callsFake(() => {
+      return {
+        error: 'An error has occurred'
+      } as any;
+    });
+
+    assert.strictEqual(pid.getProcessName(123), undefined);
+  });
+
   it('retrieves process name on Linux', () => {
     sinon.stub(os, 'platform').callsFake(() => 'linux');
     sinon.stub(fs, 'existsSync').callsFake(() => true);
@@ -66,16 +85,43 @@ describe('utils/pid', () => {
     assert.strictEqual(pid.getProcessName(123), undefined);
   });
 
-  it('returns undefined when retrieving process name fails', () => {
+  it('returns undefined when retrieving process name on Windows fails', () => {
+    sinon.stub(os, 'platform').callsFake(() => 'win32');
+    sinon.stub(child_process, 'spawnSync').callsFake(() => {
+      return {
+        error: 'An error has occurred'
+      } as any;
+    });
+
+    assert.strictEqual(pid.getProcessName(123), undefined);
+  });
+
+  it('returns undefined when extracting process name on Windows', () => {
     sinon.stub(os, 'platform').callsFake(() => 'win32');
-    sinon.stub(child_process, 'execSync').throws();
+    sinon.stub(child_process, 'spawnSync').callsFake(command => {
+      if (command === 'wmic') {
+        return {
+          stdout: 'Caption\
+pwsh.exe\
+'
+        };
+      }
+
+      return {
+        error: 'An error has occurred'
+      } as any;
+    });
 
     assert.strictEqual(pid.getProcessName(123), undefined);
   });
 
   it('stores retrieved process name in cache', () => {
     sinon.stub(os, 'platform').callsFake(() => 'win32');
-    sinon.stub(child_process, 'execSync').callsFake(() => 'pwsh');
+    sinon.stub(child_process, 'spawnSync').callsFake(() => {
+      return {
+        stdout: 'pwsh'
+      } as any;
+    });
 
     pid.getProcessName(123);
 

src/utils/pid.ts

@@ -1,11 +1,16 @@
-import * as os from 'os';
+import { spawnSync } from 'child_process';
 import * as fs from 'fs';
-import { execSync } from 'child_process';
+import * as os from 'os';
 import { cache } from './cache';
 
 function getProcessNameOnMacOs(pid: number): string | undefined {
-  const stdout = execSync(`ps -o comm= ${pid}`, { encoding: 'utf8' });
-  return stdout.trim();
+  const res = spawnSync('ps', ['-o', 'comm=', pid.toString()], { encoding: 'utf8' });
+  if (res.error || res.stderr) {
+    return undefined;
+  }
+  else {
+    return res.stdout.trim();
+  }
 }
 
 function getProcessNameOnLinux(pid: number): string | undefined {
@@ -20,8 +25,24 @@ function getProcessNameOnLinux(pid: number): string | undefined {
 }
 
 function getProcessNameOnWindows(pid: number): string | undefined {
-  const stdout = execSync(`wmic PROCESS where ProcessId=${pid} get Caption | find /V "Caption"`, { encoding: 'utf8' });
-  return stdout.trim();
+  const findProcess = spawnSync('wmic', ['PROCESS', 'where', `ProcessId=${pid}`, 'get', 'Caption'], { encoding: 'utf8' });
+  if (findProcess.error || findProcess.stderr) {
+    return undefined;
+  }
+  else {
+    const getPid = spawnSync('find', ['/V', '"Caption"'], {
+      encoding: 'utf8',
+      input: findProcess.stdout,
+      // must include or passing quoted "Caption" will fail
+      windowsVerbatimArguments: true
+    });
+    if (getPid.error || getPid.stderr) {
+      return undefined;
+    }
+    else {
+      return getPid.stdout.trim();
+    }
+  }
 }
 
 export const pid = {
@@ -45,16 +66,11 @@ export const pid = {
     }
 
     if (getPidName) {
-      try {
-        processName = getPidName(pid);
-        if (processName) {
-          cache.setValue(pid.toString(), processName);
-        }
-        return processName;
-      }
-      catch {
-        return undefined;
+      processName = getPidName(pid);
+      if (processName) {
+        cache.setValue(pid.toString(), processName);
       }
+      return processName;
     }
 
     return undefined;