WIP #70: config.js can now configure which plugins are loaded, and what order...

WIP #70: config.js can now configure which plugins are loaded, and what order they are going to be used in

service-worker.js

@@ -24,7 +24,16 @@ if (typeof self.SamizdatConfig !== 'object' || self.SamizdatConfig === null) {
         // and move on?
         defaultPluginTimeout: 10000,
         // plugins settings namespace
-        plugins: {}
+        plugins: {},
+        // this defines which plugins get loaded,
+        // and the order in which they are deployed to try to retrieve content
+        // assumption: plugin path = ./plugins/<plugin-name>.js
+        strategy: [
+            'fetch',
+            'cache',
+            'gateway-ipns',
+            'gun-ipfs'
+        ]
     }
 }
 
@@ -33,12 +42,13 @@ if (typeof self.SamizdatConfig !== 'object' || self.SamizdatConfig === null) {
 // order in which plugins are loaded defines the order
 // in which they are called!
 try {
+    // get the config
+    self.importScripts("./config.js")
+    // only now load the plugins (config.js could have changed the defaults)
     self.importScripts(
-        "./config.js",
-        "./plugins/fetch.js",
-        "./plugins/cache.js",
-        "./plugins/gateway-ipns.js",
-        "./plugins/gun-ipfs.js");
+        ...self.SamizdatConfig.strategy.map(
+            pluginName => `./plugins/${pluginName}.js`
+        ))
 } catch(e) {
     // we only get a cryptic "Error while registering a service worker"
     // unless we explicitly print the errors out in the console