improve env var proxy handling

index.js

@@ -19,14 +19,24 @@ var tunnel = require('tunnel');
 var agents = require('./lib/agents');
 exports.agents = agents;
 
-// save the original globalAgents for restoration later.
+var ENV_VAR_PROXY_SEARCH_ORDER = [ 'https_proxy', 'HTTPS_PROXY', 'http_proxy', 'HTTP_PROXY' ]
+
+// save the original settings for restoration later.
 var ORIGINALS = {
  http: pick(http, 'globalAgent', 'request'),
- https: pick(https, 'globalAgent', 'request')
+ https: pick(https, 'globalAgent', 'request'),
+ env: pick(process.env, ENV_VAR_PROXY_SEARCH_ORDER)
 };
 function resetGlobals() {
  assign(http, ORIGINALS.http);
  assign(https, ORIGINALS.https);
+ var val;
+ for (var key in ORIGINALS.env) {
+ val = ORIGINALS.env[key];
+ if (val != null) {
+ process.env[key] = val;
+ }
+ }
 }
 
 /**
@@ -48,6 +58,23 @@ function tryParse(url) {
 
 globalTunnel.isProxying = false;
 
+function findEnvVarProxy() {
+ var key, val, result;
+ for (var i = 0; i < ENV_VAR_PROXY_SEARCH_ORDER.length; i++) {
+ key = ENV_VAR_PROXY_SEARCH_ORDER[i];
+ val = process.env[key];
+ if (val != null) {
+ // get the first non-empty
+ result = result || val;
+ // delete all
+ // NB: we do it here to prevent double proxy handling (and for example path change)
+ // by us and the `request` module or other sub-dependencies
+ delete process.env[key];
+ }
+ }
+ return result;
+}
+
 /**
  * Overrides the node http/https `globalAgent`s to use the configured proxy.
  *
@@ -73,14 +100,13 @@ globalTunnel.initialize = function(conf) {
  conf = clone(conf)
  } else {
  // nothing passed - parse from the env
- conf = tryParse(process.env['http_proxy']);
- if (!conf) {
+ var envVarProxy = findEnvVarProxy();
+
+ if (!envVarProxy) {
  globalTunnel.isProxying = false;
  return;
  } else {
- // TODO: we do it here to prevent double path change by us and the `request` module
- // Is it too bad to do so?
- delete process.env['http_proxy'];
+ conf = tryParse(envVarProxy);
  }
  }