Add more documentation to computed balances controller

4 files changed, 77 insertions, 6 deletions

diff --git a/app/scripts/controllers/computed-balances.js b/app/scripts/controllers/computed-balances.js
index 907b087cf..cf2e05333 100644
--- a/app/scripts/controllers/computed-balances.js
+++ b/app/scripts/controllers/computed-balances.js
@@ -2,8 +2,16 @@ const ObservableStore = require('obs-store')
 const extend = require('xtend')
 const BalanceController = require('./balance')
 
+/**
+ * Background controller responsible for syncing
+ * and computing ETH balances for all accounts
+ */
 class ComputedbalancesController {
-
+  /**
+   * Creates a new controller instance
+   *
+   * @param {Object} [opts] Controller configuration parameters 
+   */
   constructor (opts = {}) {
     const { accountTracker, txController, blockTracker } = opts
     this.accountTracker = accountTracker
@@ -19,6 +27,9 @@ class ComputedbalancesController {
     this._initBalanceUpdating()
   }
 
+  /**
+   * Updates balances associated with each internal address
+   */
   updateAllBalances () {
     Object.keys(this.balances).forEach((balance) => {
       const address = balance.address
@@ -26,12 +37,23 @@ class ComputedbalancesController {
     })
   }
 
+  /**
+   * Initializes internal address tracking
+   *
+   * @private
+   */
   _initBalanceUpdating () {
     const store = this.accountTracker.store.getState()
     this.syncAllAccountsFromStore(store)
     this.accountTracker.store.subscribe(this.syncAllAccountsFromStore.bind(this))
   }
 
+  /**
+   * Uses current account state to sync and track all
+   * addresses associated with the current account
+   *
+   * @param {Object} store Account tracking state
+   */
   syncAllAccountsFromStore (store) {
     const upstream = Object.keys(store.accounts)
     const balances = Object.keys(this.balances)
@@ -50,6 +72,13 @@ class ComputedbalancesController {
     })
   }
 
+  /**
+   * Conditionally establishes a new subscription
+   * to track an address associated with the current
+   * account
+   *
+   * @param {string} address Address to conditionally subscribe to
+   */
   trackAddressIfNotAlready (address) {
     const state = this.store.getState()
     if (!(address in state.computedBalances)) {
@@ -57,6 +86,12 @@ class ComputedbalancesController {
     }
   }
 
+  /**
+   * Establishes a new subscription to track an
+   * address associated with the current account
+   *
+   * @param {string} address Address to conditionally subscribe to
+   */
   trackAddress (address) {
     const updater = new BalanceController({
       address,
diff --git a/app/scripts/lib/createProviderMiddleware.js b/app/scripts/lib/createProviderMiddleware.js
index 4e667bac2..8a939ba4e 100644
--- a/app/scripts/lib/createProviderMiddleware.js
+++ b/app/scripts/lib/createProviderMiddleware.js
@@ -1,6 +1,10 @@
 module.exports = createProviderMiddleware
 
-// forward requests to provider
+/**
+ * Forwards an HTTP request to the current Web3 provider
+ *
+ * @param {{ provider: Object }} config Configuration containing current Web3 provider
+ */
 function createProviderMiddleware ({ provider }) {
   return (req, res, next, end) => {
     provider.sendAsync(req, (err, _res) => {
diff --git a/app/scripts/lib/port-stream.js b/app/scripts/lib/port-stream.js
index a9716fb00..260530e63 100644
--- a/app/scripts/lib/port-stream.js
+++ b/app/scripts/lib/port-stream.js
@@ -6,6 +6,13 @@ module.exports = PortDuplexStream
 
 inherits(PortDuplexStream, Duplex)
 
+/**
+ * Creates a stream that's both readable and writable.
+ * The stream supports arbitrary JavaScript objects.
+ *
+ * @class
+ * @param {Object} port Remote Port object
+ */
 function PortDuplexStream (port) {
   Duplex.call(this, {
     objectMode: true,
@@ -15,8 +22,13 @@ function PortDuplexStream (port) {
   port.onDisconnect.addListener(this._onDisconnect.bind(this))
 }
 
-// private
-
+/**
+ * Callback triggered when a message is received from
+ * the remote Port associated with this Stream.
+ *
+ * @private
+ * @param {Object} msg - Payload from the onMessage listener of Port
+ */
 PortDuplexStream.prototype._onMessage = function (msg) {
   if (Buffer.isBuffer(msg)) {
     delete msg._isBuffer
@@ -27,14 +39,31 @@ PortDuplexStream.prototype._onMessage = function (msg) {
   }
 }
 
+/**
+ * Callback triggered when the remote Port
+ * associated with this Stream disconnects.
+ *
+ * @private
+ */
 PortDuplexStream.prototype._onDisconnect = function () {
   this.destroy()
 }
 
-// stream plumbing
-
+/**
+ * Explicitly sets read operations to a no-op
+ */
 PortDuplexStream.prototype._read = noop
 
+
+/**
+ * Called internally when data should be written to
+ * this writable stream.
+ * 
+ * @private
+ * @param {*} msg Arbitrary JavaScript object to write
+ * @param {string} encoding Encoding to use when writing payload
+ * @param {Function} cb Called when writing is complete or an error occurs
+ */
 PortDuplexStream.prototype._write = function (msg, encoding, cb) {
   try {
     if (Buffer.isBuffer(msg)) {
diff --git a/app/scripts/lib/setupMetamaskMeshMetrics.js b/app/scripts/lib/setupMetamaskMeshMetrics.js
index 40343f017..79b9cb249 100644
--- a/app/scripts/lib/setupMetamaskMeshMetrics.js
+++ b/app/scripts/lib/setupMetamaskMeshMetrics.js
@@ -1,6 +1,9 @@
 
 module.exports = setupMetamaskMeshMetrics
 
+/**
+ * Injects an iframe into the curerent document for testing
+ */
 function setupMetamaskMeshMetrics() {
   const testingContainer = document.createElement('iframe')
   testingContainer.src = 'https://metamask.github.io/mesh-testing/'