add support for custom storage class configured with process.env.STORAGE_CLASS

Author: k2s

lib/server/bootevent.js

@@ -155,7 +155,8 @@ function boot (env, language) {
         });
       } else {
         //TODO assume mongo for now, when there are more storage options add a lookup
-        require('../storage/mongo-storage')(env, function ready(err, store) {
+        const storage = process.env.STORAGE_CLASS ? require('../storage/custom-storage') : require('../storage/mongo-storage')
+        storage(env, function ready(err, store) {
           // FIXME, error is always null, if there is an error, the index.js will throw an exception
           if (err) {
             console.info('ERROR CONNECTING TO MONGO', err);

lib/storage/custom-storage.js

@@ -0,0 +1,46 @@
+/**
+ *
+ * @param env
+ * @param cb
+ */
+function init (env, cb) {
+  // detect what storage driver loader class to get
+  let [driverName, packageName] = process.env.STORAGE_CLASS.split('@')
+  if (packageName === undefined) {
+    packageName = driverName
+  }
+  driverName = driverName || 'default'
+
+  // get the storage driver loader class
+  // eslint-disable-next-line security/detect-non-literal-require
+  const module = require(packageName)
+  const DriverClass = module[driverName]
+
+  // pass configuration to storage driver loader, so it can decide what it needs based on the config
+  const driver = new DriverClass(env)
+
+  const callback = (err, res) => {
+    console.info(`custom storage driver '${DriverClass.name}' from '${packageName}' was loaded`)
+    cb(err, res)
+  }
+
+  // load the storage driver
+  if (driver.needsFallback) {
+    // the driver needs original MongoDB driver
+    require('./mongo-storage')(env, function ready (err, store) {
+      if (err) {
+        return cb(err, store)
+      }
+
+      // pass the MongoDB storage to be used by the driver
+      driver.setFallback(store)
+      // load the driver
+      driver.init(callback)
+    })
+  } else {
+    // we don't need anything special, let's the driver load
+    driver.init(callback)
+  }
+}
+
+module.exports = init