check fee module locked and enable fee before refunding all fees

[vuong177]

Description

• Add check locked fee module and fee is enabled before refunding all fees

closes: #1321

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[codecov-commenter]

Codecov Report

Merging #1341 (5e78870) into main (9f70a07) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main    #1341      +/-   ##
==========================================
+ Coverage   80.33%   80.35%   +0.01%     
==========================================
  Files         166      166              
  Lines       12071    12083      +12     
==========================================
+ Hits         9697     9709      +12     
  Misses       1918     1918              
  Partials      456      456              

Impacted Files	Coverage Δ
modules/apps/29-fee/ibc_middleware.go	94.18% <100.00%> (+0.43%)	⬆️

[seantking]

Just a couple more nits and then it's good to merge :)

Also, please add a changelog entry.

[damiannolan]

Ack, pending suggestions for nits

[vuong177]

Just a couple more nits and then it's good to merge :)

Also, please add a changelog entry.

@seantking thanks for your thorough reviewing. I updated !

[seantking]

Approved but left a suggestion for the changelog :) Great work

[colin-axner]

It is good for us to think about why we even have "fee enabled channels". This is because non fee enabled channels still use the same middleware stack as fee enabled channels. Thus this check prevents closing of a non fee enabled channel. A key requirement of the middleware design is that middleware not enabled for a specific channel must not affect the behaviour of that channel (this requirement is broken by returning an error).

We should:

• return nil if the fee is not enabled (exit early)
• move this check above IsLocked

The reasoning for the second point is that we don't want non fee enabled channels to get affected by the fee module getting locked. A locked fee module should not affect non fee enabled channels

btw, thanks for the contribution! :)

[vuong177]

Thanks you. It helped me understand. I'll make the changes.

[colin-axner]

Thanks!

[colin-axner]

@vuong177 thanks for the contribution :) You'll need to bring the pr up to date with main for it to be merged

[vuong177]

@colin-axner thank you !