fix the issue that access key doesn't work if appid passed is in different case

[nobodyiam]

What's the purpose of this PR

fix the issue that access key doesn't work if appid passed is in different case

Which issue(s) this PR fixes:

Fixes #3626

Brief changelog

Use tree set with CASE_INSENSITIVE_ORDER comparator.

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[codecov-io]

Codecov Report

Merging #3627 (82a3b82) into master (3de1d72) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@             Coverage Diff              @@
##             master    #3627      +/-   ##
============================================
+ Coverage     50.97%   50.99%   +0.01%     
- Complexity     2329     2330       +1     
============================================
  Files           449      449              
  Lines         14026    14026              
  Branches       1426     1426              
============================================
+ Hits           7150     7152       +2     
+ Misses         6389     6388       -1     
+ Partials        487      486       -1     

Impacted Files	Coverage Δ	Complexity Δ
...nfigservice/service/AccessKeyServiceWithCache.java	84.69% <100.00%> (ø)	22.00 <0.00> (ø)
...ervice/service/ReleaseMessageServiceWithCache.java	85.88% <0.00%> (-1.18%)	24.00% <0.00%> (-1.00%)
.../framework/apollo/spring/property/SpringValue.java	89.47% <0.00%> (+1.75%)	21.00% <0.00%> (+1.00%)
...rk/apollo/spring/property/SpringValueRegistry.java	88.88% <0.00%> (+5.55%)	11.00% <0.00%> (+1.00%)

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[nisiyong]

It looks good to me, but how we avoid this situation next time.
It seems that there had serval issues about sensitive appId previously, do we need some common utils to fix the same issues?

[nobodyiam]

It seems that there had serval issues about sensitive appId previously, do we need some common utils to fix the same issues?

You are right, there have been several case sensitive issues. Previously we also have this issue for namespace names, and we fixed that via NamespaceUtil#normalizeNamespace.
Maybe we could also write an AppUtil to normalize the app id?

https://github.com/ctripcorp/apollo/blob/943bbb4d56bd9d3bbec291ea17136099a3a60b7c/apollo-configservice/src/main/java/com/ctrip/framework/apollo/configservice/util/NamespaceUtil.java#L28-L40

[nisiyong]

@nobodyiam I think we can merge this PR first, and create a new issue to build AppUtil.

[nisiyong]

LGTM