very rough and PoC test implementation of JSON-based config (ref. #31)

__tests__/config.json

@@ -0,0 +1,16 @@
+{
+    "plugins": [{
+        "name": "fetch"
+    },{
+        "name": "cache"
+    },{
+        "name": "basic-integrity",
+        "integrity": [{
+            "/test.json": "sha384-kn5dhxz4RpBmx7xC7Dmq2N43PclV9U/niyh+4Km7oz5W0FaWdz3Op+3K0Qxz8y3z"
+        }],
+        "uses": [{
+            "name": "fetch"
+        }]
+    }],
+    "loggedComponents": ["service-worker", "fetch", "cache"]
+}

docs/ARCHITECTURE.md

@@ -76,7 +76,7 @@ uses: config.uses
 
 ## Fetching a resource via LibResilient
 
-Whenever a resource is being fetched on a LibResilient-enabled site, the `service-worker.js` script dispatches plugins in the set order. This order is configured via the `plugins` key of the `LibResilientConfig` variable, usually set in `config.js` config file.
+Whenever a resource is being fetched on a LibResilient-enabled site, the `service-worker.js` script dispatches plugins in the set order. This order is configured via the `plugins` key of the `LibResilientConfig` variable, usually set in `config.json` config file.
 
 A minimal default configuration is hard-coded in case no site-specific configuration is provided. This default configuration runs these plugins:
 

libresilient.js

@@ -499,7 +499,7 @@ if ('serviceWorker' in navigator) {
         var serviceWorkerPath = scriptFolder + 'service-worker.js'
         self.log('browser-side', 'Service Worker script at: ' + serviceWorkerPath)
         // TODO: is there a way to provide config params for the Service Worker here?
-        // TODO: it would be good if the config.js script could reside outside of the libresilient directory
+        // TODO: it would be good if the config.json file could reside outside of the libresilient directory
         // TODO: https://developer.mozilla.org/en-US/docs/Web/API/ServiceWorkerContainer/register
         navigator.serviceWorker.register(serviceWorkerPath, {
             // TODO: what is the scope relative to? is it the HTML file that included it, or this script?

plugins/gun-ipfs.js

@@ -34,7 +34,7 @@ if (typeof window === 'undefined') {
         let defaultConfig = {
             // Gun nodes to use
             gunNodes: ['https://gunjs.herokuapp.com/gun'],
-            // the pubkey of the preconfigured Gun user; always needs to be set in config.js
+            // the pubkey of the preconfigured Gun user; always needs to be set in config.json
             gunPubkey: null,
             // the IPFS gateway we're using for verification when publishing; default is usually ok
             ipfsGateway: 'https://gateway.ipfs.io'

plugins/ipns-ipfs.js

@@ -26,7 +26,7 @@
 
         // sane defaults
         let defaultConfig = {
-            // the pubkey of the preconfigured IPNS node; always needs to be set in config.js
+            // the pubkey of the preconfigured IPNS node; always needs to be set in config.json
             ipnsPubkey: null,
             // the IPFS gateway we're using for verification when publishing; default is usually ok
             ipfsGateway: 'https://gateway.ipfs.io'

service-worker.js

@@ -39,7 +39,7 @@ if (!Array.isArray(self.LibResilientPlugins)) {
 // initialize the LibResilientConfig array
 // 
 // this also sets some sane defaults,
-// which then can be modified via config.js
+// which then can be modified via config.json
 if (typeof self.LibResilientConfig !== 'object' || self.LibResilientConfig === null) {
     self.LibResilientConfig = {
         // how long do we wait before we decide that a plugin is unresponsive,
@@ -93,17 +93,23 @@ self.log = function(component, ...items) {
 // 
 // everything in a try-catch block
 // so that we get an informative message if there's an error
+let initServiceWorker = async () => {
     try {
 
         // get the config
         // 
         // self.registration.scope contains the scope this service worker is registered for
-    // so it makes sense to pull config from `config.js` file directly under that location
+        // so it makes sense to pull config from `config.json` file directly under that location
         // 
         // TODO: providing config directly from browser-side control script via postMessage?
-    // TODO: `updateViaCache=imports` allows at least config.js to be updated using the cache plugin?
+        // TODO: `updateViaCache=imports` allows at least config.json to be updated using the cache plugin?
+        console.debug('* * * LOADING CONFIG * * *')
         try {
-        self.importScripts(self.registration.scope + "config.js")
+            //self.importScripts(self.registration.scope + "config.json")
+            var cdata = await fetch(self.registration.scope + "config.json")
+            cdata = await cdata.json()
+            self.LibResilientConfig.plugins = cdata.plugins
+            self.LibResilientConfig.loggedComponents = cdata.loggedComponents
             self.log('service-worker', 'config loaded.')
         } catch (e) {
             self.log('service-worker', 'config loading failed, using defaults')
@@ -112,12 +118,12 @@ try {
         // create the LibResilientPluginConstructors map
         // the global... hack is here so that we can run tests; not the most elegant
         // TODO: find a better way
-    var LibResilientPluginConstructors = self.LibResilientPluginConstructors || new Map()
+        self.LibResilientPluginConstructors = self.LibResilientPluginConstructors || new Map()
         
         // this is the stash for plugins that need dependencies instantiated first
         var dependentPlugins = new Array()
         
-    // only now load the plugins (config.js could have changed the defaults)
+        // only now load the plugins (config.json could have changed the defaults)
         while (self.LibResilientConfig.plugins.length > 0) {
             
             // get the first plugin config from the array
@@ -207,6 +213,7 @@ try {
         console.error(e)
         throw e
     }
+}
 
 /**
  * fetch counter per clientId
@@ -672,7 +679,8 @@ let getResourceThroughLibResilient = (request, clientId, useStashed=true, doStas
 |* === Setting up the event handlers                                     === *|
 \* ========================================================================= */
 
-self.addEventListener('install', event => {
+self.addEventListener('install', async (event) => {
+    event.waitUntil(initServiceWorker())
     // TODO: Might we want to have a local cache?
     // "COMMIT_UNKNOWN" will be replaced with commit ID
     self.log('service-worker', "0. Installed LibResilient Service Worker (commit: COMMIT_UNKNOWN).");