Is Clojure concurrency support still disabled on App Engine? - google-app-engine

In a recent blog post, Adrian Mouat said that App Engine doesn't support Clojure concurrency, such as agents. However, GAE Java supports threads as of the App Engine 1.6.4 release.
Is the Clojure concurrency model fully supported on App Engine?

I know one would have to use their Thread Manager API for thread creation. For appengine front ends each created thread would still be tied to the current request. On an appengine back end you would be able to make background thread would persist after the request was handled. I do not know about other libraries,but appengine-magic has not been updated since Google App Engine SDK 1.6.3.1 release with little activity on the forks,but updating it to the latest appengine api was a summer of code project proposal for 2012.

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Who starts the google cloud scheduler?

I can't find any documentation on how gcp scheduler works under the hood. An App Engine is needed in the project, so I assume that the Http calls or Pub/Sub messages are started from the App Engine.
Currently I can use a cloud scheduler even without an App Engine in the project. Apparently a compute engine that also contains a permanently running VM is also sufficient. Could someone confirm my assumptions please or does anyone have sources on this?
I can't tell you how work Cloud Scheduler under the hood. I can just tell you that works well!
I'm sure there is a VM, or a cluster of VM, on Google serverless environment, and your Cloud Scheduler job is set on it. It's serverless, the under the hood doesn't matter, it works, and it's what I want!
Now, the relation with App Engine can be confusing. In fact, there is no longer relation between the product now, but you need the App Engine API activated on your project to use Cloud Scheduler. This strange things is normal if you have been using Google Cloud for a while. At the beginning, only App Engine existed, and Datastore, Cloud Task, Cloud Scheduler was all "modules" of App Engine. Years, after years, google has refactored and extracted these modules to create independent products, as you can see them today. However, some relations are still present, like the API activation.

Firebase Admin SDK in App Engine with Java 8

Previously the Firebase Admin SDK would not run on App Engine with automatic scaling. Probably it will create some threads and the Thread class or something like that is not whitelisted.
Now that Google has given us support for Java 8 on App Engine (and removed the whitelist), would this problem be gone? Will the Firebase Admin SDK work on App Engine with automatic scaling?
Firebase Admin SDK still won't work in the AppEngine Java 8 runtime without manual scaling, for several reasons:
The threads support available in the Java 8 runtime comes with some limitations. For instance, any thread not created using the AppEngine's ThreadManager interface cannot call AppEngine APIs. This means these threads cannot make outgoing network calls.
The database client code in the SDK spawns long-running threads. The only way to do that in the AppEngine environment is via background thread support. The SDK specifically looks for this feature when deployed in AppEngine. I've tried to run the SDK with this requirement relaxed, but it doesn't work. It seems request-scoped threads cannot outlive the request even in the new Java 8 runtime.
However, you should be able to use the FirebaseAuth interface (used for custom token minting, ID token verification and user management) in the AppEngine, without manual scaling. This part of the SDK supports running on request-scoped threads.

Google Cloud Datastore requires app engine?

Im creating a Node.js website that probably won't have loads of traffic, and was looking into cheap solutions to host the site. Came across Google cloud services offering free usage for their services with limits. A f1-mirco is more than enough for my needs, but I will happily pay for some usage if it goes over by any chance.
I wanted to setup a linux centOS 7 on GCE (which I already did), and run my application and REST API on it. Now here comes the problem.
I tried to use Google's datastore service, but it sprung an app engine instance and without it datastore won't work.
Is datastore entirely relying on app engine to function?? In the docs, it said if you use any of the client API, it requires app engine. What can I do to not use the client api and query data then? Don't want to use the app engine at the moment or datastore is just not for me then?
Thanks for any help!
Some of the underlying infrastructure of Cloud Datastore and App Engine are still tied together for creation, etc. So while creating an Cloud Datastore database also defines an App Engine instance for the project, it doesn't require you to use it. You don't get charged for App Engine either, unless you decide to deploy an App using it.
You should be totally fine use the Google Cloud Node client library on the f1 micro instance.

why is javascript node.js not on google app engine

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.

Port a live system from App Engine Helper to App Engine Patch

I am running a live system that is currently serving about 20K pages a day which is based on App Engine Helper (Python) with session support provided by AppEngine utilities.
One problem that I have been having is that sessions are occasionally randomly logging out. I would like to try using the App Engine Patch, since it has "native" django session support, but I am worried that this is possibly going to be like doing a brain transplant. Specifically, current database models are all inhereted from BaseModel provided by the App Engine Helper. While, App Engine Patch does not have this inheritance.
Does anyone know if it is possible to migrate a live system from App Engine Helper to App Engine Patch? If so, do you have any advice or warnings that I should heed, before attempting this transition?
Thank you and kind regards
Alex
After further investigations, I discovered that newer versions of Django and App Engine Helper have built in support for sessions. After migrating to this system, my problems of randomly losing sessions have been resolved.
Alex
You should think about porting your system not to App Engine Patch but to Django-nonrel (by app-engine-patch authors).
I moved from google-app-engine-django and app-engine-patch to Django-nonrel is because first two are not maintained any more.

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