Support reading package name from WSK_PACKAGE env var #10

diff --git a/README.md b/README.md
index d3b8943..7b79ffa 100644
--- a/README.md
+++ b/README.md

@@ -124,7 +124,7 @@
 
 Add the configuration below to your [launch.json](https://code.visualstudio.com/docs/editor/debugging#_launch-configurations). Replace `MYACTION` with the name of your action and `ACTION.js` with the source file containing the action. When you run this, it will start wskdebug and should automatically connect the debugger.
 
-```
+```json
     "configurations": [
         {
             "type": "node",
@@ -145,6 +145,41 @@
 
 For troubleshooting, you can run the debugger in verbose mode by adding `"-v"` to the `args` array.
 
+#### Control wskprops credentials
+
+To use custom credentials from a custom `.wskprops` and/or use a developer-specific openwhisk package name, but avoid committing that into your source control system, you can use an `.env` file.
+
+1. Put this `.env` file in your VS Code project root:
+
+    ```
+    WSK_CONFIG_FILE=/Users/user/.wskprops-custom
+    WSK_PACKAGE=my-package
+    ```
+    
+   Set either of the variables as needed.
+
+2. Make sure to not commit this file into source control, by e.g. adding `.env` to a `.gitignore` file.
+
+2. Add an `envFile` setting to the `.vscode/launch.json`, which you can share with co-workers and commit to source control:
+
+    ```json
+    "configurations": [
+        {
+            "type": "node",
+            "request": "launch",
+            "name": "wskdebug",
+            "runtimeExecutable": "wskdebug",
+            "args": [ "MYACTION", "ACTION.js", "-l" ],
+            "localRoot": "${workspaceFolder}",
+            "remoteRoot": "/code",
+            "outputCapture": "std",
+            "envFile": "${workspaceFolder}/.env"
+        }
+    ]
+    ```
+
+
+
 <a name="nodejs-multiple-actions"></a>
 ### Node.js: Multiple actions
 

diff --git a/examples/nodejs/.env b/examples/nodejs/.env
new file mode 100644
index 0000000..d2c1e30
--- /dev/null
+++ b/examples/nodejs/.env

@@ -0,0 +1,2 @@
+WSK_PACKAGE=wskdebug-examples
+#WSK_CONFIG_FILE=<absolute-path-to-custom-wskprops>

diff --git a/examples/nodejs/.vscode/launch.json b/examples/nodejs/.vscode/launch.json
index aeb9f4e..47501f7 100644
--- a/examples/nodejs/.vscode/launch.json
+++ b/examples/nodejs/.vscode/launch.json

@@ -49,7 +49,19 @@
             "localRoot": "${workspaceFolder}",
             "remoteRoot": "/code",
             "outputCapture": "std"
+        },
+        {
+            "type": "node",
+            "request": "launch",
+            "name": "wskdebug with WSK_PACKAGE",
+            "runtimeExecutable": "wskdebug",
+            "args": [
+                "webaction"
+            ],
+            "localRoot": "${workspaceFolder}",
+            "remoteRoot": "/code",
+            "outputCapture": "std",
+            "envFile": "${workspaceFolder}/.env"
         }
-
     ]
 }
\ No newline at end of file

diff --git a/index.js b/index.js
index 96a83cb..0406efe 100644
--- a/index.js
+++ b/index.js

@@ -258,6 +258,10 @@
     argv.invokeParams = argv.P;
     argv.invokeAction = argv.a;
     argv.onChange = argv.r;
+
+    if (process.env.WSK_PACKAGE && argv.action && !argv.action.includes("/")) {
+        argv.action = `${process.env.WSK_PACKAGE}/${argv.action}`;
+    }
 }
 
 function printErrorAndExit(err, argv) {

diff --git a/test/wskdebug.test.js b/test/wskdebug.test.js
index ca8e941..959168e 100644
--- a/test/wskdebug.test.js
+++ b/test/wskdebug.test.js

@@ -22,13 +22,32 @@
 
 // tests basic cli
 
-const wskdebug = require('../index');
+let wskdebug = require('../index');
 
 const test = require('./test');
 const assert = require('assert');
 const stripAnsi = require('strip-ansi');
 const {execSync} = require('child_process');
 
+const mockRequire = require('mock-require');
+
+function mockDebugger() {
+    const receivedArgv = {};
+
+    class MockDebugger {
+        constructor(argv) {
+            Object.assign(receivedArgv, argv);
+        }
+
+        start() {}
+        run() {}
+    }
+
+    mockRequire("../src/debugger", MockDebugger);
+    wskdebug = mockRequire.reRequire("../index");
+    return receivedArgv;
+}
+
 describe('wskdebug cli', function() {
 
     it("should print version (via wskdebug.js)", async function() {
@@ -66,4 +85,25 @@
         assert.equal(stripAnsi(stdio.stdout.trim()), require(`${process.cwd()}/package.json`).version);
     });
 
+    it("should take action argument", async function() {
+        const argv = mockDebugger();
+
+        await wskdebug(`action`);
+        assert.strictEqual(argv.action, "action");
+
+        await wskdebug(`package/action`);
+        assert.strictEqual(argv.action, "package/action");
+    });
+
+    it("should use WSK_PACKAGE env var as package name", async function() {
+        const argv = mockDebugger();
+
+        process.env.WSK_PACKAGE = "envPackage";
+        await wskdebug(`action`);
+        assert.strictEqual(argv.action, "envPackage/action");
+
+        // cli package takes precedence
+        await wskdebug(`package/action`);
+        assert.strictEqual(argv.action, "package/action");
+    });
 });