How to force py-qgis-server to not use cache for GetCapabilities request ?

[TANK2003]

How to force py-qgis-server to not use cache for GetCapabilities request ? Or for all request if it is not possible

Thanks

[dmarteau]

Are you talking about the projects cache ? If you do not use project's cache , they will be reloaded at each request which will be a huge performance penalty.

You can always use a cache size of 1, but I don't see any reason to give up projects cache.

What problem are you trying to solve ?

[TANK2003]

Re,

Description of the problem

• Yes i'am talking about the project Cache
• My stack :
  • I have a plugin on top QGIS SERVER to handle layer permissions depending on the authorization token (in the header of the request).
  • When application boot a getcapabilities is called to list all layers which the user connected have rigths
• My problem :
  • when user 1 perform the first getcapabilities request, py-qgi-server generate a cache;
  • When user 2 perform another getcapabilities request after 2 mins, the cache of user 1 is return

So i'am tryng to regenerate getcapabilities request at each query

Maybe a solution ?

Maybe if i whrite a custom Loader schemes ? Where a projet will be the combination of project name &user connected ?

[dmarteau]

Yes i'am talking about the project Cache

Your question is about the GetCapabilities response, which is not related to project's cache.

As a matter of fact the capabilities document is not cached at all by the server, but use standard client cache headers:

Py-qgis-server return getcapabilities response with Etag headers, if the client request the same capabability document with a If-None-Match header with a matching Etag value then a 304 Not Modified is returned.

If you want the capabilities to be returned on each request, then bypass client cache Etag headers (from javascript, use non-cached fetch requests) , then the request will reach your plugin.

You may also disable etag generation on server side by disabling the TRUST_LAYER_METADATA option.

[TANK2003]

Will try it known and give a feedback. Thanks !

[TANK2003]

Hello, For all this i have disable the etag header on py-qgis-server.

I have try :

• To bypass cached request in both postman/application (running in chrome) by adding in header Cache-Control:no-store: my plugin is not trigger on each GetCapabilities request

• Force chrome to not use disk cache by adding a new parameter in the GetCapabilities url &t=new Date().getTime() : the querry is not responding frome the disk cache any more but my plugin is not trigger on each GetCapabilities request

[dmarteau]

• Check logs, eventually in debug mode, to check what's happening with requests.
• Check that your plugin is correctly initialized. You must find the following in logs

  est-py-qgis-server-qgis-server-1  | 2023-04-12 10:37:15,057 WARNING [31]    Qgis: : SUCCESS - plugin foo  initialized
  test-py-qgis-server-qgis-server-1  | 2023-04-12 10:37:15,057    INFO    [31]    Loaded plugin foo
  ...

• Use curl to issue direct requests to py-qgis-server and check headers.

In debug mode, you must have something like:

test-py-qgis-server-qgis-server-1  | 2023-04-12 10:39:14,890    DEBUG   [31]    Qgis: Server: REQUEST:GetCapabilities
test-py-qgis-server-qgis-server-1  | 2023-04-12 10:39:14,890    DEBUG   [31]    Qgis: Server: SERVICE:WFS
...

The above tell you that the request has reached Qgis server instance. If you get this and your plugin is loaded then your plugin must be called. Otherwise there is something wrong with your plugin.

[dmarteau]

Alternatively you may setup the management server mode with the MANAGEMENT_ENABLED option.

Then go to http://localhost:19876/plugins to check the status of the plugins.

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This issue is stale because it has been open for 30 days with no activity.

[github-actions[bot]]

This issue was closed because it has been inactive for 14 days since being marked as stale.