I'm currently building a live web application based upon the PubSubHubBub protocol. However, I encountered several issues.
First, I'm in search of a hub application that I can run on my server. There are several applications, but most of them are not mature yet, or they don't support the 0.3 spec. The official google hub runs on the Google App Engine and can even be executed locally. Unfortunately, "Tasks will not run automatically. Push the 'Run' button to execute each task." This behaviour is useful for debugging and understanding the workflow, but in some live tests, it would be nice not to invoke all tasks manually. Is there a way to tweak the local app engine due automatically run tasks?
Next, I have a question concerning the spec itself. The Google reference implementation provides the initial publish method bound to the outpoint uri + /publish. But this is not reflected in the specs.
So are there any mature hubs that can be run locally for debugging? Or are there ways to configure the offical google app engine hub to run locally and to execute tasks directly?
Thanks in advance
The new 1.3.4 App Engine SDK automatically runs tasks. Just upgrade your SDK to take advantage of it.
Next, I have a question concerning the spec itself. The Google reference implementation provides the initial publish method bound to the outpoint uri + /publish. But this is not reflected in the specs.
/publish is the only endpoint provided by the hub. As per the discovery section of the spec, that is the one you advertise.
Btw, https://github.com/pubsubhubbub/PubSubHubbub/wiki/Hubs lists all currently known hubs and software.
I also made my own hub that implements the 0.4 spec; see https://github.com/cweiske/phubb
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I have a Quarkus application already deployed on Google Cloud Run.
It depends on MySQL, hence there is an instance started on Cloud SQL.
Next step in my deployment process is to add keycloak. From what I've read the best option seems to be Google App Engine.
The approved answer in this question gave me some good insight of what needs to be done ... mostly.
What I did was:
Locally I made a sub-directory in the main project.
In that directory I added the app.yaml and the Dockerfile (as described here for instance).
There I executed the said two commands: gcloud init and gcloud app deploy.
I had my doubts about this set up and they were backed up by the error I got eventually:
ERROR: (gcloud.app.deploy) INVALID_ARGUMENT: The first service (module) you upload to a new application must be the 'default' service (module). Please upload a version of the 'default' service (module) before uploading a version for the 'morph-keycloak-service' service (module).
I understand my set up breaks the overall structure of the project but I'm not sure how to mix those two application with the right services.
I understand keycloak is a stateful application, hence cannot live on Cloud Run (by the way the intention is for keycloak to use the same database instance shared with the application).
So does any one know a more sensible set up, or what can I move in mine in order to fix it?
In short:
The answer really is in reading the error message (thanks #gaefan) - about the error itself it explains enough. So I just commented out the service: my-keycloak-service line in the app.yaml (thus leaving gcloud to implicitly mark it as the default one) and the deployment continued.
Eventually keycloak didn't connect to the database but if I don't manage to adjust the configurations that would probably be a subject to a different question.
On the point of project structure and functionality:
First off, thanks #NoCommandLine and #guillaume-blaquiere for your input!
#NoCommandLine the application on Cloud Run is sort of a headless REST API enabled backend. Most of the API calls are secured by keycloack. A next step in the deployment process would be to port an existing UI (React) client on the Firebase hosting (or on another suitable service - I'm still not completely sure which approach is best) and in order for the users to work with this client properly they must make an SSO through keycloak first.
I'm quite new to GCP and the number and variants of the available options are still overwhelming to me - one must get familiar with the nuances but I guess it takes time. So I'm still taking suggestions on how to adjust my project structure to fit better the services stack. Thanks!
My app is deployed on the python 3.7 Google App Engine standard environment. It has a bug that causes it to silently fail when a certain library function gets called. I'd like to set some log points inside the library function, but I'm not seeing a way to do that. Is it possible to set log points inside external dependencies using Stackdriver? If so, how?
You can use Stackdriver debugger. It allows you to inspect the state of an application, at any code location, without stopping or slowing down the running app and you can configure your Python application to use Stackdriver Debugger.
Also Stackdriver Trace is a distributed tracing system that collects latency data from your applications and displays it in the Google Cloud Platform Console.
I want to build a web application using a mixture of App Engine Standard and Flexible Environment as described in the Google docs (flexible as microservice where third party software is needed, standard for everything else).
I need the mentioned microservice to run latex, a few linux tools and python. What is the best way to go from here?
My guess is:
Build a docker container from a Linux OS and use either Google Pub/Sub, Google Task Queue or plain HTTP for communication with the Standard Env App.
But how is this custom runtime then managed by Google regarding security updates, scaling, loadbalancing and everything else promised in the docs?
Sorry for the rather generic question, the infos are thin IMHO and so I have to ask.
It would be your responsability to re-build the custom runtime images (done during every app deployment) to incorporate security updates. If your Dockerfile references other Google-supplied base images then the security updates for them will be automatically picked up in the process. But for any additional packages or customisations you added to your runtime you may need to incorporate the updates yourself.
Scaling depends on your app's configuration (your responsability), see Service scaling settings.
Google automatically load-balances traffic across your app's instances.
I have an standard appengine app currently running. I am currently developing another flask app which will use flexible runtime. I am wondering is it possible for me to have both apps in same project?
Yes, it is possible, with each of your "applications" being implemented as separate services/modules in the same GAE app. Services/modules offer complete code isolation, see Comparison of service isolation and project isolation.
See also: Custom runtime for non-flexible environment app?
There is an even easier way to do this that doesn't require creating a separate service :)
Since you are only developing your second application, you do not need to set it as the default version to serve traffic to the public. You only need to access it yourself, (or perhaps whoever you give the URL to). The only drawback really is that you will not be able to access your project at the default url, usually .appspot.com
Therefore, you can simply deploy your flexible app engine project, but make sure you don't give it any traffic sharing or promote it to the main version!! You can then access your version simply by clicking on the version in the google cloud console, or by visiting http://-dot-.appspot.com/ (It was not possible to access individual versions like this for flexible for quite some time, but this has now been resolved.)
We have Java servlets up and running on GAE, using blobstore, datastore and other cloud services.
Currently, we're starting a migration process to cloud Endpoints and we've hit an issue: if we use a different GAE project, we would not be able to query regarding current datastore entities (to the best of my knowledge, Google doesn't want you to do this - see
this question
and the GAE terms of service - section 3.3d), so we need to use the same project for both.
I looked up whether it's possible to have one GAE instance running Java servlets and one instance running Endpoints, but I found no conclusive answer anywhere.
If we try to implement and something goes wrong, we're looking at a potentially major issue for our users, so we need to be sure beforehand.
Has anyone tried something similar, and can assure us that this works?
You have 2 options to run the old and the new code inside the same app (thus with no issues sharing access to the datastore) but as separate engine instances, so they can be developed/deployed/managed independently:
as different versions of the same app/module(s):
the old version remains the default, the new one can be accessed at a different URL during development (possibly via URL routing)
you can use traffic splitting to do live A/B testing on the new code and for gradual final migration until you make the new version the default
as different modules of the same app:
both can run (fully functional) side by side indefinitely, but you need to be more careful during development
traffic is routed to the modules in several possible ways
final migration is done by publishing the new URLs, eventually re-directing the old URLs and finally bringing down the old module code
The 2 approaches can even be combined, if needed, as the final solution described by the OP's in this somehow similar question (for the python environment, but java equivalents exist): Google App Engine upgrading part by part