translated to coffee, made API more verbose, added phantomJS script t…

…o automate web-based authorization (WIP)

.gitignore

@@ -1,4 +1,5 @@
 config
+node_modules
 lib-cov
 *.seed
 *.log

index.coffee

@@ -0,0 +1,160 @@
+request = require("request")
+exec = require("child_process").exec
+querystring = require("querystring")
+
+endpoint_auth = "https://accounts.google.com/o/oauth2/auth"
+endpoint_token = "https://accounts.google.com/o/oauth2/token"
+
+module.exports = (opts) ->
+    opts.redirect_uri or= "http://localhost:3000/callback"
+    opts.refresh_tokens or= []
+
+    ###
+    Constructs a google OAuth2 request url using the provided opts.
+    Spawns an http server to handle the redirect. Once user authenticates
+    and the server parses the auth code, the server process is closed
+    (Assuming the user has closed the window. For future, add redirect after
+    authentication to a page with instructions to close tab/window).
+
+    Some scopes:
+    https://www.googleapis.com/auth/userinfo.profile
+    https://www.googleapis.com/auth/drive.readonly.metadata
+    ###
+
+    getAuthCode = (scope, openURICallback, callback) ->
+
+        # default: open the system's web browser
+        openURICallback or= (uri, cb) ->
+            #TODO: Make OS agnostic w/ xdg-open, open, etc.
+            exec "open '#{uri}'", cb
+
+        qs =
+            response_type: "code"
+            client_id: opts.client_id
+            redirect_uri: opts.redirect_uri
+            scope: scope
+
+        uri = endpoint_auth + "?" + querystring.stringify(qs)
+
+        parseCode = (req, res) ->
+            #for gdrive-cli:
+            #instead of just closing the connection, redirect to an informational page
+            console.log "Stopping server ..."
+            server.close()
+
+            #split url by ? so we just have the querystring left
+            #extract out the auth code
+            callback null, querystring.parse(req.url.split("?")[1]).code
+
+        console.log "Starting server ..."
+        server = require("http").createServer((req, res) ->
+            parseCode req, res    if req.url.match(/callback/)
+        ).listen(3000)
+
+        openURICallback uri, (err) ->
+            callback err
+
+
+    ###
+    Given the acquired authorization code and the provided opts,
+    construct a POST request to acquire the access token and refresh
+    token.
+
+    @param {String} code Can be acquired with getAuthCode
+    ###
+    getTokensForAuthCode = (code, callback) ->
+        form =
+            code: code
+            client_id: opts.client_id
+            client_secret: opts.client_secret
+            redirect_uri: opts.redirect_uri
+            grant_type: "authorization_code"
+
+        request.post
+            url: endpoint_token
+            form: form
+        , (err, req, body) ->
+            if err? then return callback err
+            callback null, JSON.parse(body)
+
+    ###
+    Given a refresh token and provided opts, returns a new
+    access token. Tyically the access token is valid for an hour.
+
+    @param {String} refresh_token The refresh token. Can be acquired
+    through getTokensForAuthCode function.
+    ###
+    getAccessTokenForRefreshToken = (refresh_token, callback) ->
+        form =
+            refresh_token: refresh_token
+            client_id: opts.client_id
+            client_secret: opts.client_secret
+            grant_type: "refresh_token"
+
+        request.post
+            url: endpoint_token
+            form: form
+        , (err, req, body) ->
+            if err? then callback err
+            callback null, JSON.parse(body)
+
+
+    ###
+    Given google account name and password, use phantomJS to login a user into google services.
+    Afterwards navigate the browser to a given URL.
+    The purpose of this is to allow a command line tool to authorize
+    an application (or itself) to access the user's data.
+    ###
+
+    automaticGoogleWebLogin = (username, password, followUpURI, cb) ->
+        childProcess = require "child_process"
+        phantomjs = require "phantomjs"
+        path = require "path"
+
+        childArgs = [
+            path.join(__dirname, "lib/google-login-phantomjs-script.coffee")
+            username
+            password
+            followUpURI
+        ]
+
+        child = childProcess.spawn phantomjs.path, childArgs
+
+        child.stdout.on "data", (data) ->
+            process.stdout.write data
+
+        child.stderr.on "data", (data) ->
+            process.stderr.write data
+
+        child.on "exit", (code) ->
+            console.log "phantomjs exited with code:", code
+            if code isnt 0
+                return cb "phantomjs exited with code #{code}", code
+            cb null
+
+
+    authorizeApplication = (username, password, scope, cb) ->
+        getAuthCode scope, (uri, cb) ->
+            automaticGoogleWebLogin username, password, uri, cb
+        , cb
+
+    ### 
+    Convenience dunction
+    Use this to get an access token for a specific scope
+    ###
+    getAccessToken: (scope, cb) ->
+        refresh_token = opts.refresh_tokens[scope]
+        if refresh_token
+            getAccessTokenForRefreshToken refresh_token, cb
+        else
+            async.waterfall [
+                getAuthCode,
+                getTokensForAuthCode
+            ], (err, result) ->
+                # store the refresh_token for future use
+                opts.refresh_token[scope] = result?.refresh_token
+                cb err, result?.access_token
+
+    return {
+        authorizeApplication: authorizeApplication
+    }