Google App Engine

Nitro is compatible with Google App Engine. The Narwhal appengine package is a component of the Ecosystem.

For an example Nitro application that runs on AppEngine and leverages AppEngine services like the DataStore, download and study the blog-gae example.

Datastore

The Python ext/db api is supported. The API is slightly different to better fit JavaScript.

var db = require("google/appengine/ext/db");

var Category = db.Model("Category", {
    label: new db.StringProperty(),
    category: new db.ReferenceProperty({referenceClass: Category})
});

var c = new Category({keyName: "news", label: News"});
c.put();
var key = ...
var c1 = Category.get(key);
var c2 = Category.getByKeyName("news");
var categories = Category.all().limit(3).fetch();

Blobstore

form:

var blobstore = require("google/appengine/api/blobstore");

exports.GET = function(env) {
    return {data: {
        uploadURL: blobstore.createUploadUrl("/test")
    }}
}

<form action="{uploadURL}" method="POST" enctype="multipart/form-data">
    <p>
        <input type="file" name="file" />
    </p>
    <p>       
        <button type="submit">Upload</button>
    </p>
</form>

upload:

var blobstore = require("google/appengine/api/blobstore");

exports.GET = function(env) {
    return {data: {
        uploadURL: blobstore.createUploadUrl("/save")
    }}
}

save:

var blobstore = require("google/appengine/api/blobstore");

exports.POST = function(env) {
    var blobs = blobstore.getUploadedBlobs(env);

    return {
        status : 303,
        headers : {
            "Location": "/serve?key=" + blobs.file.toString()
        }
    };     
}

serve:

var blobstore = require("google/appengine/api/blobstore");

exports.GET = function(env) {
    var params = new Request(env).GET();
    return blobstore.serve(params.key, env);
}

URL Fetch

var fetch = require("google/appengine/api/urlfetch").fetch;

var response = fetch("http://www.appenginejs.org"),
    html = response.content.decodeToString("UTF-8");

Images

var images = require("google/appengine/api/images");
var i = images.resize(params.image.data, 640, 480);

Email

var EmailMessage = require("google/appengine/api/mail").EmailMessage;

new EmailMessage({
    sender: "george.moschovitis@gmail.com",
    to: "receiver@site.com",
    subject: "My email",
    body: template.render(params)
}).send();

Memcache

var memcache = require("google/appengine/api/memcache");

var fragment = memcache.get("fragment");
if (!fragment) {
    ...
    memcache.set("fragment", fragment);
}

Users

var users = require("google/appengine/api/users");

var user = users.getCurrentUser();

if (users.isCurrentUserAdmin()) {
    ...
}

var url = user.createLoginURL();

Task Queue

var taskqueue = require("google/appengine/api/labs/taskqueue");

taskqueue.add({url: "/worker", method: "GET", params: {par1: "hello", par2: "world"}});  

var task = new Task({url: "/worker", method: "GET", params: {par1: "hello", par2: "world"}});
task.add("customqueue");

Forms

var Article = require("article").Article,
    ModelForm = require("google/appengine/ext/db/forms").ModelForm,
    ArticleForm = ModelForm(Article);

    ...

var form = new ArticleForm(params, {instance: article});
    ...
    form.save();

Example

For an example of the usage of this library have a look at the example/ directory. For a more advanced example have a lok at the blog-gae example.

Component status

This library is under construction but usable. Substantial parts of the Python API are converted.

google/appengine/api/memcache: 80% (usable)
google/appengine/api/urlfetch: 80% (usable)
google/appengine/api/mail: 60% (usable)
google/appengine/api/images: 60% (usable)
google/appengine/api/users: 80% (usable)
google/appengine/api/labs/taskqueue: 80% (usable)
google/appengine/ext/db: 80% (usable, expect minor API changes)
google/appengine/ext/db/forms: 30% (expect API changes)
google/appengine/ext/blobstore: 40% (usable)

Google App Engine

This is a community project, not affiliated in any way with Google.