Make DEFAULT_LIMIT monkey patchable

[spacemanspiff2007]

What do these changes do?

Currently its not possible to change DEFAULT_LIMIT.
This change allows this:

import aiohttp
aiohttp.streams.DEFAULT_LIMIT = 10 * aiohttp.streams.DEFAULT_LIMIT

Are there changes in behavior for the user?

No

Related issue number

#4453

Checklist

• I think the code is well written
• Unit tests for the changes exist
• Documentation reflects the changes
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[spacemanspiff2007]

@webknjaz could you review this change, too? It would fix my application from crashing.

[spacemanspiff2007]

I changed it as requested - it should be possible to merge this.

[spacemanspiff2007]

Is there anything I can do to get this merged?

[robhaswell]

I am another user who would like to see this functionality.

[spacemanspiff2007]

@webknjaz :
Are there any plans to merge this? This is a tiny change which would prevent my application from throwing errors.

[asvetlov]

Sorry, I don't support this PR.
If you want to change the default buffer size -- please pass the desired value into client.get() or a similar call instead of monkey-patching. ClientSession can accept the session-default value as the argument constructor as well.

Sure, it requires a bigger pull request than initially proposed but I believe that explicit way is much better.

[spacemanspiff2007]

Thank you for your reply. The crash happens when using aiohttp together with aiohttp-sse-client but I think if it's a possible Session arg this would be still fine.
A working example and finished PR would be here, it just has to be merged.

I am just looking for any (simple) way to change the buffer so my application doesn't go down with an exception

[asvetlov]

@spacemanspiff2007 sorry again, I misled you and myself by writing controversial recommendations.

To don't bother you again I've prepared a fix myself as #5065
I hope it solves your needs.

[asvetlov]

Closing the PR for the sake of #5056

[spacemanspiff2007]

Thank you very much for your efforts and for the solution!

[robhaswell]

Sorry @asvetlov I must be being dumb, but I can't see how #5056 is related to the size of the line buffer?

[asvetlov]

Sorry for the typo, the actual number is #5065 instead of #5056

[robhaswell]

Got it. Thanks for addressing this issue.