From b8870a758612e991aecbae511ffe43a2a4ee7d46 Mon Sep 17 00:00:00 2001
From: Marcel Klehr <mklehr@gmx.net>
Date: Fri, 27 Dec 2013 16:02:54 +0100
Subject: [PATCH] Run npm in a separate worker process

---
 src/package.json                     |  5 +++--
 src/static/js/pluginfw/installer.js  |  2 +-
 src/static/js/pluginfw/npm-master.js | 19 +++++++++++++++++++
 src/static/js/pluginfw/npm-worker.js | 24 ++++++++++++++++++++++++
 4 files changed, 47 insertions(+), 3 deletions(-)
 create mode 100644 src/static/js/pluginfw/npm-master.js
 create mode 100644 src/static/js/pluginfw/npm-worker.js

diff --git a/src/package.json b/src/package.json
index 0c59cfbb8..f455961b2 100644
--- a/src/package.json
+++ b/src/package.json
@@ -27,7 +27,7 @@
                       "nodemailer"              : "0.3.x",
                       "jsdom-nocontextifiy"     : "0.2.10",
                       "async-stacktrace"        : "0.0.2",
-                      "npm"                     : "1.2.x",
+                      "npm"                     : "*",
                       "ejs"                     : "0.6.1",
                       "graceful-fs"             : "1.1.5",
                       "slide"                   : "1.1.3",
@@ -40,7 +40,8 @@
                       "swagger-node-express"    : "1.2.3",
                       "channels"                : "0.0.x",
                       "jsonminify"              : "0.2.2",
-                      "measured"                : "0.1.3"
+                      "measured"                : "0.1.3",
+                      "rpc-stream"              : "1.0.x"
                      },
   "bin":             { "etherpad-lite": "./node/server.js" },
   "devDependencies": {
diff --git a/src/static/js/pluginfw/installer.js b/src/static/js/pluginfw/installer.js
index e56026167..498487162 100644
--- a/src/static/js/pluginfw/installer.js
+++ b/src/static/js/pluginfw/installer.js
@@ -1,6 +1,6 @@
 var plugins = require("ep_etherpad-lite/static/js/pluginfw/plugins");
 var hooks = require("ep_etherpad-lite/static/js/pluginfw/hooks");
-var npm = require("npm");
+var npm = require("./npm-master");
 
 var npmIsLoaded = false;
 var withNpm = function (npmfn) {
diff --git a/src/static/js/pluginfw/npm-master.js b/src/static/js/pluginfw/npm-master.js
new file mode 100644
index 000000000..031744b14
--- /dev/null
+++ b/src/static/js/pluginfw/npm-master.js
@@ -0,0 +1,19 @@
+/**
+ * This module exposes the same methods as installer.js, but runs them in a separate child process
+ */
+var child_process = require('child_process')
+  , rpc = require('rpc-stream')
+
+var worker = child_process.fork(__dirname+'/npm-worker', {silent:true})
+
+var client = rpc()
+
+worker.stdout.pipe(client).pipe(worker.stdin)
+
+worker.stderr.pipe(process.stdout)
+
+module.exports = {
+  commands: client.wrap(['install', 'uninstall', 'search'])
+, load: function(opts, cb) {cb()}
+, on: function(){}
+}
\ No newline at end of file
diff --git a/src/static/js/pluginfw/npm-worker.js b/src/static/js/pluginfw/npm-worker.js
new file mode 100644
index 000000000..0df859b09
--- /dev/null
+++ b/src/static/js/pluginfw/npm-worker.js
@@ -0,0 +1,24 @@
+/**
+ * This is a worker that should be run using child_process.fork (see installer-master.js for reference)
+ * Stdin and stdout are connected to an rpc server exposing the methods of installer.js
+ */
+var RPC = require('rpc-stream')
+  , npm = require('npm')
+
+npm.load({}, function (er) {
+  if(er) throw er
+})
+console.log = function() {process.stderr.write(Array.prototype.slice(arguments).join('')+'\n')}
+
+var server = RPC({
+  search: function(args, cb) {
+    npm.commands.search.apply(npm, Array.prototype.concat(args, [cb]))
+  }
+, install: function(args, cb) {
+    npm.commands.install.apply(npm, Array.prototype.concat(args, [cb]))
+  }
+, uninstall: function(args, cb) {
+    npm.commands.uninstall.apply(npm, Array.prototype.concat(args, [cb]))
+  }
+})
+process.stdin.pipe(server).pipe(process.stdout)
\ No newline at end of file