Newbie to Datastore. I found two tutorials on the GCP site to use Datastore on App Engine. Which one should I use?
There are subtle differences in how the APIs work.
https://cloud.google.com/datastore/docs/datastore-api-tutorial
uses package (import com.google.appengine.api.datastore.Entity;)
vs.
https://cloud.google.com/appengine/docs/standard/java/building-app/cloud-datastore
uses package (import com.google.cloud.datastore.Entity)
Question: Is there a preferred package to use and call the datastore API while on App Engine - com.google.cloud.datastore.Entity vs. com.google.appengine.api.datastore.Entity?
The library with this package com.google.appengine.api.datastore (aka "Datastore API for Java") is intended for use by Java 7 and Java 8 applications which run on AppEngine.
The library with this package com.google.cloud.datastore (aka "Cloud Datastore client library") is intended for use by any Java 8 application regardless of where it is deployed (GKE, GCE, on-premises etc)
From the docs:
Datastore API for Java is a low-level Datastore API built into the App Engine SDK to provide direct access to all Datastore features and is described throughout the App Engine Datastore documentation for Java.
Cloud Datastore client library is a library that can be used by apps in the App Engine standard Java 8 runtime, by applications in the App Engine flexible environment, and by non App Engine applications as well.
So, according to Google, both are valid choices subject to these limitations ...
If you are running Java 7 then you cannot use Cloud Datastore client library
If your application is not deployed to AppEngine then you cannot use Datastore API for Java
These limitations describe the scenarios in which one or other of these libraries cannot be used. Google offers no advice on which one should be used. This is because the two libraries are functionally equivalent so, assuming that the limitations described above do not apply to your usage, the choice is probably moot.
Google created the V8 JavaScript engine: V8 compiles JavaScript source code directly into machine code when it is first executed.
Node.js is built on V8 - why is Google not offering any Node.js servers like Microsoft Azure?
Google App Engine would be a natural place to put Node.js.
Do you know why Google is not doing just that?
Node.js is maintained by Joyent, who is in a way a competitor of Google.
Node.js has no link what so ever with Google but is in fact built on top of an open source project started by Google.
Google might jumped into this business just like Azure did, but there are already so many PaaS doing it, it might not be worth it. I have never used GAE, but my understanding is that it is quite different that other PaaS and you have to use GAE libraries to make your code run.
Which, this is my personal feeling, is not really what the Node.js community is looking for.
Node.js is used to quickly make a fast lightweight app, a big share for APIs for Phone apps for example.
Nevertheless if you are looking for a PaaS for Node.js, the are quite a few out there:
Joyent (nodejitsu)
dotCloud which has WebSockets support.
Windows Azure
Nodester (bought by App Fog recently)
Any Cloud Foundry host should support Node.js too.
and many more...
Those are just some names off the top of my head. There quite a few but those are the major ones.
Oh there is Heroku too, but they don't have support for WebSocket which is a bummer for any Socket.IO based app.
As of June 2014, Google had a limited preview for custom languages on Google App Engine (which is different from Google Compute Engine).
Watch Building Node.js applications with App Engine and Custom Runtimes and check out https://cloud.google.com/appengine/docs/managed-vms/:
App Engine now offers a second hosting option: Managed VMs. The Managed VM hosting environment lets you run App Engine applications on configurable Compute Engine Virtual Machines (VMs).
You can also use Managed VMs to deploy user-configurable custom runtimes, such as for Node.js and other runtimes.
The procedure to get into the beta is:
Sign up and create a Managed VM project
Managed VMs are in Limited Preview, you must sign up for access to this feature, create a billing-enabled project, and tell us about your project so we can whitelist it to run in a Managed VM. Follow these steps:
Sign up for access to Managed VMs.
Join the app-engine-managed-vms Google Group to participate in discussions about Managed VMs.
Projects (or apps - they are the same thing) must be in a U.S. data center. If you're planning to use an existing project, skip to the next step. Otherwise, create a new app in a U.S. data center. Navigate to https://preview.appengine.google.com and create a new app.
Enable billing for the project. Visit the page https://cloud.google.com/console/project/apps~, where is the ID of your project. Click on Settings in the left menu and then enable billing. If your app is billed under a Premier account, email us at app-engine-managed-vm-tt-id#google.com to have your new Cloud project billed under the same account.
Send an email to app-engine-managed-vm-tt-id#google.com with the application ID in the subject line.
When we receive your email, we’ll configure some resources behind the scenes and notify you via email when your project is ready to go. The email includes final instructions for setup. If you encounter an error while following these instructions, contact us at app-engine-managed-vm-tt-id#google.com.
You can easily install node on Google Compute Engine (which basically is a virtual computer). Here is a link:
https://developers.google.com/datastore/docs/getstarted/start_nodejs/
Regards
Lars
after years of experiences in google appengine, i switch to other cloud services now.
i think google appengine is actually an old fashion service in cloud computing industry. which is slow to new technology, difficult to deploy, time wasting to learn the apis and lacking of a lot of features you need in languages you use.
regardless of google's large community, i would not suggest anyone to use google appengine.
[newer paas]
i strongly recommend you to use openshift, appfog, heroku .etc's new paas cloud computing technologies, which are far more extensible, less change needing, more migrable from one platform to another, more freely coding in the beauty of the natural lanuage and its standard libraries without ugly platform specific apis.
[iaas]
if you want more control over the running os environment, you may give linode, digital ocean, amazon, google cloud engine, microsoft azure etc. iaas providers a try.
Because App Engine is a platform-as-a-service, and in order to add a new language/stack to GAE, Google need to create mid-level libraries that interface with the plethora of App Engine's services.
Moreover, all App Engine apps is sandboxed and has several functionalities restricted from inside their sandbox environment. This means that beside the need to create service libraries, Google also need to create a secured sandbox environment for any language/stack that they try to introduce into GAE.
I personally think the second reason is why Google does not introduce support for new language/stack as aggressive as Azure did. App Engine is, in a way, more 'managed' than Azure, and has a larger initial development cost for new language/stack.
It has been released as of March 2016.
https://cloudplatform.googleblog.com/2016/03/Node.js-on-Google-App-Engine-goes-beta.html
Node.js has recently enabled support for Google Cloud users. The main document pages are:
Node.js on Google Cloud Platform
Google Cloud Datastore — Google Developers
It seems to require at the moment a Compute Engine instance.
Background: App Engine Standard vs App Engine Flexible
There seems to be some confusion on this topic because there are two versions of App Engine: Standard and Flexible. NodeJS is supported on App Engine Flexible but NOT on App Engine Standard. (See here for a more complete explanation of the differences).
App Engine Standard scales in seconds (as opposed to minutes for the Flexible environment), and has a free tier, so you can develop and demo without spending a dime. These benefits come at the cost of flexibility. App Engine Standard only supports certain languages and libraries, doesn't allow writing to disk nor SSH. In other words, the environment is standardized.
Answer: NodeJS Support on App Engine Standard
If you are interested in NodeJS support on App Engine Standard, please star this issue: https://issuetracker.google.com/issues/67711509.
Google addresses features that get attention from the community (see here). The best way to give your attention to this feature, is to star it on the Google Issue tracker linked to above.
Google announced on March, 21st 2016 that Node.js on Google App Engine was going beta: https://cloudplatform.googleblog.com/2016/03/Node.js-on-Google-App-Engine-goes-beta.html?m=1
This was expected as Google also joined the Node.js Foundation and Google develops the V8 JavaScript engine which powers Chrome and Node.js: https://nodejs.org/en/blog/announcements/welcome-google/
Google announced a partnership with NodeSource at the same time.
Google has just announced support for Node.js on App Engine.
See: https://cloud.google.com/nodejs/
Here's an example of how to deploy Node.js app on App Engine.
Google is a software-conservative company. Programming a backend in JavaScript would be absolutely unimaginable for Google's managers. Creating infrastructure Google itself won't be using is not a good investment. Reference: Notes from the Mystery Machine Bus
(Jun 2021) This question is almost a decade old, and many things have changed since the OP. TL;DR: JavaScript and/or Node.js are supported in 6 different serverless compute platforms from Google: 4 on GCP and one each from Google Workspace and Firebase plus release dates:
Google App Engine - Standard (Jun 2018) - announcement, docs (Node.js 10, 12, 14; 8 is deprecated)
Google App Engine - Flexible (Mar 2016) - announcement (general release), docs (Most Node.js versions)
Google Cloud Functions (Mar 2017) - announcement (general release), docs (Node.js 10, 12, 14; 8 is deprecated)
Cloud Functions for Firebase (Mar 2017) - announcement, docs (same versions as Google Cloud Functions)
Google Cloud Run (Apr 2019) - announcement (general release), docs (Any Node.js version you can put in a container)
Google Apps Script (Aug 2009) - announcement, docs (JS-only, not Node; Rhino ES3/ES5 + extensions originally; now v8 & ES6+ [Mar 2020])
Also see Google Cloud's overall support of/for Node.js.
Currently i try to connect (via JPA/Datanucleus) with an application, hosted by Google App Engine, to the database service of database.com (Salesforce)
After many hours of reading and trying, i could not find any solution.
So, is it even possible??
Some Information....
Database.com provides JPA: http://forcedotcom.github.com/java-sdk/jpa-provider, but i could not found any sdk on this side, but i found a jar-file hosted by grepcode http://grepcode.com/snapshot/repo1.maven.org/maven2/com.force.sdk/force-jpa/22.0.7-BETA/ - Possibly there is currently no official release ...
The problem is that this SDK from Salesforce needs datanucleus 2.0, but Google App Engine includes only datanucleus 1.1.5. So i try to update theses libaries and found this.... code.google.com/p/datanucleus-appengine/ . I tried a few hours to replace the old libaries and to use the newer, but unsuccessfully. The error was that eclipse could not find some libaries, because the newer libaries, provided by the side above, have different package structure -
I am thankful for any help...
Kotake
The official release of the JPA provider is available on Maven Central:
http://search.maven.org/remotecontent?filepath=com/force/sdk/force-jpa/22.0.7-BETA/force-jpa-22.0.7-BETA.jar
The external connection restriction won't be a limiting factor because the JPA adapter connects to Database.com over https using a SOAP API.
I can't speak to the challenges around getting DN 2.0 running on GAE. Perhaps GAE support can help with that?
As stated here in the App Engine docs, you cannot make direct connections to external servers from GAE (except over http or https using the app engine specific url APIs). You will need to find some other way to get data out of your remote database.
This link describes how to solve your problem:
How to use Force.com Database SDK on Google APP Engine
(He has updated the Saleforce SDK source code to allow it to work without problem on GAE.)
I'm finding alternatives for Google App Engine for startup. The preconfigured service hosting include security, networking, scaling, database, backup, application, maturity and etc.. Because we have no experts on each parts. It's too hard operating whole service stack properly for only one application programmer.
What other services can I consider for this?
The term you want to search for is PaaS or Platform-as-a-Service. I do not claim to be an expert in this nacent field, however my basic understanding of the key players other than Google App Engine are:
Amazon AWS - My understanding is that Amazon's Web Services gives you bare-bones OS installs that you can completely own. While this allows for more configuration than App Engine, this also means you are on the hook for patching security holes and what not. (Right?)
Heroku - App Engine type functionality, except for Ruby
AppHarbor - App Engine type functionality, except for .NET
Microsoft Azure - Amazon AWS type functionality, except for Windows/The Microsoft stack.
The CloudCamp awards 2011 serves as a nice list of PaaS services
I've been wondering: does Google uses AppEngine for its own products?
Yes.
Google's app engine is a consumer-facing front-end for the same server resources that google uses internally.
None of the major world-facing google products DIRECTLY use app engine through the API, but many internal tools built by googlers for googlers do use it, including all the limitations that are placed on the public.
Run corporate applications on Google App Engine? Yes [they] do.