Add flask config: MAX_CONTENT_LENGTH

[xpgcrx]

Add flask config to limit the allowed payload.
closes: #35196

I set it to limit to 1MB.
Before and after adding this config, I tried sending a string larger than 1MB from the Edit User page.
Before adding the config, it was possible to send; after adding, I confirmed that the attached error page was received.

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[dirrao]

How about triggering a DAG with input configuration? Does it require more than 1MB? If we move this configuration to the web server section in airflow cfg, then we can set based on our requirements. For user profile information, is it feasible to restrict the size of form fields rather than relying on the defaults?

[xpgcrx]

Thank you for your comment.

How about triggering a DAG with input configuration?

Sorry, what does this mean?

Does it require more than 1MB?

I'm not really sure what would be an appropriate value. Do you have any ideas?

If we move this configuration to the web server section in airflow cfg, then we can set based on our requirements.

Does this mean instead of hardcoding the value, we can set an item in airflow.cfg and get that value as a flask config?

For user profile information, is it feasible to restrict the size of form fields rather than relying on the defaults?

Certainly, I feel it's feasible. Sorry, could you please clarify what you mean by "rather than relying on the defaults"?

[dirrao]

Thank you for your comment.

How about triggering a DAG with input configuration?

Sorry, what does this mean?

Does it require more than 1MB?

I'm not really sure what would be an appropriate value. Do you have any ideas?

We can pass the JSON payload while triggering the DAG from the Airflow UI. JSON payload can be arbitrary length. It is much bigger. I haven't come across a use case where we pass more than 1MB. However, I am just checking.

If we move this configuration to the web server section in airflow cfg, then we can set based on our requirements.

Does this mean instead of hardcoding the value, we can set an item in airflow.cfg and get that value as a flask config?

Trying to see if can avoid hardcoding in the code.

For user profile information, is it feasible to restrict the size of form fields rather than relying on the defaults?

Certainly, I feel it's feasible. Sorry, could you please clarify what you mean by "rather than relying on the defaults"?

I mean relying on the same default value for multiple forms in the Airflow UI.

[potiuk]

@hussein-awala ?

[hussein-awala]

I was checking to see if it accepts float or if we need to round the calculated value, but it looks like Flask implicitly does that.

LGTM, just a small nit, IMHO allowed_payload_size is a better name.

[dirrao]

LGTM