Adding a configurable timeout for each uplink

lib/config_def.yaml

@@ -12,6 +12,10 @@ uplinks:
   npmjs:
     url: https://registry.npmjs.org/
 
+    # amount of time to wait for repository to respond before giving up
+    # and use the local cached copy
+    timeout: 3000
+
     # maximum time (in seconds) in which data is considered up to date
     #
     # default is 2 minutes, so server won't request the same data from

lib/up-storage.js

@@ -32,6 +32,9 @@ function Storage(config, mainconfig) {
 	_setupProxy.call(this, this.url.hostname, config, mainconfig, this.url.protocol === 'https:')
 
 	this.config.url = this.config.url.replace(/\/$/, '')
+	if (isNaN(parseFloat(this.config.timeout)) || !isFinite(this.config.timeout)) {
+		this.config.timeout = 5000
+	}
 	return this
 }
 
@@ -105,6 +108,7 @@ Storage.prototype.request = function(options, cb) {
 		body: json,
 		ca: this.ca,
 		proxy: this.proxy,
+		timeout: this.config.timeout
 	}, function(err, res, body) {
 		var error
 		if (!err) {