Merge pull request #2 from timruffles/master

add `disableFallbacks()` to disable development defaults

Author: ctavan

README.md

@@ -98,6 +98,16 @@ var config = getenv.multi({
 
 ```
 
+### env.disableFallbacks()
+
+Disallows fallbacks in environments where you don't want to rely on brittle development defaults (e.g production, integration testing). For example, to disable fallbacks if we indicate production via `NODE_ENV`:
+
+```javascript
+if (process.env.NODE_ENV === 'production') {
+  getenv.disableFallbacks();
+}
+```
+
 ## Changelog
 
 ### v0.3.0
@@ -115,6 +125,7 @@ var config = getenv.multi({
 - Christoph Tavan <[email protected]>
 - Jonas Dohse <[email protected]>
 - Jan Lehnardt (@janl): `getenv.multi()` support.
+- Tim Ruffles <[email protected]>: `disableFallbacks()`
 
 ## License
 

lib/getenv.js

@@ -1,12 +1,18 @@
 var util = require("util");
 
+var fallbacksDisabled = false;
+
 function _value(varName, fallback) {
   var value = process.env[varName];
   if (value === undefined) {
     if (fallback === undefined) {
       throw new Error('GetEnv.Nonexistent: ' + varName + ' does not exist ' +
                       'and no fallback value provided.');
     }
+    if (fallbacksDisabled) {
+      throw new Error('GetEnv.DisabledFallbacks: ' + varName + ' relying on fallback ' + 
+                      'when fallbacks have been disabled');
+    }
     return '' + fallback;
   }
   return value;
@@ -98,4 +104,8 @@ getenv.multi = function multi(spec) {
   return result;
 };
 
+getenv.disableFallbacks = function() {
+  fallbacksDisabled = true;
+};
+
 module.exports = getenv;

test/fallbacks.js

@@ -0,0 +1,19 @@
+var assert = require('assert');
+
+var getenv = require('../lib/getenv');
+
+var tests = {};
+
+// order dependent test
+tests['getenv.disableFallbacks() makes relying on fallbacks an error'] = function() {
+  getenv.disableFallbacks();
+  assert.throws(function() {
+    getenv.string("url", "http://localhost");
+  });
+};
+
+
+Object.keys(tests).forEach(function(key) {
+  console.log('Test: %s', key);
+  tests[key]();
+});