Fix/kucoin query trading fees

[riven314]

Before submitting this PR, please make sure:

• Your code builds clean without any errors or warnings
• You are using approved title ("feat/", "fix/", "docs/", "refactor/")

A description of the changes proposed in the pull request:
Fix failure to get trading fees when trading symbols are more than 10 in Kucoin exchange

Tests performed by the developer:

Tips for QA testing:

[rapcmia]

LGTM

• Created user script and crosscheck on development branch and able to reproduce the issue
• Use the same script on this PR and not getting the error

test.py.log

[riven314]

seems test coverage is not enough
any suggestion on how I can update the unit test to increase the coverage? @rapcmia

[cardosofede]

LGTM!

[cardosofede]

@riven314 the PR is good to go, but the coverage is not enough. To know what you can add I will recommend you the following:

• make test
• make development-diff-cover
  That will show you the lines of your changes that are not covered.
  Also you can use PyCharm to do it, if you have questions about it ping me on discord ;) and congrats for your first PR!!!
  @rapcmia we can't merge this pr until the coverage is met.

[rapcmia]

the PR is good to go, but the coverage is not enough. To know what you can add I will recommend you the following:

• make test
• make development-diff-cover
  That will show you the lines of your changes that are not covered.

Hi @riven314 Checking if you can have a look with the test coverage so we can complete this PR? thank you

[riven314]

@rapcmia
Ok, I will add related test coverage this weekend

[nikspz]

Hi @riven314 is there any updates on this PR? thanks

[nikspz]

@riven314 Could you please ping me here if you're still working on it

[riven314]

hey @nikspz @rapcmia

I need some help on how I should update the unit tests, got a bit stuck
coz I noticed there are already some unit tests covering self.exchange._update_trading_fees, for example:
https://github.com/hummingbot/hummingbot/blob/master/test/hummingbot/connector/exchange/kucoin/test_kucoin_exchange.py#L402

I am not sure why my changes are not covered (my change is mainly on _update_trading_fees method).

[nikspz]

@riven314 You could try to run make test locally under the root hummingbot folder to see what lines need more coverage

[riven314]

@nikspz @rapcmia
I have updated branch and it should pass coverage test now
my changes included a try catch for KeyError and I tried to add a unit test to cover the raise of KeyError
but for some reason it still was not covered, so I decided to remove the try-catch
this makes the coverage test pass

[riven314]

@rapcmia @cardosofede
The build has passed. Could u help review again?

[nikspz]

Test performed:

• Cloned and installed fix branch
• Connected kucoin
• Created/started pureMM strategy using MATIC-USDT
• Review filled order events
• Review fees matched with the exchange
• Used user script and crosschecked on development branch were able to reproduce the issue
• Use the Ralph's script on this PR and not getting the error
• Manually created docker image successfully

[nikspz]

Merged the PR in behalf of foundation team to development and will be available on the next version 1.16.0