PMM-1989: fix panic

[arvenil]

This merges #13 and #22

[CLAassistant]

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2 out of 4 committers have signed the CLA.

✅ rnovikovP
✅ arvenil
❌ fukaya
❌ xuewindy

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[codecov]

Codecov Report

Merging #27 into master will increase coverage by 13.1%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master      #27      +/-   ##
==========================================
+ Coverage   66.69%   79.79%   +13.1%     
==========================================
  Files           7        7              
  Lines        1375     1376       +1     
==========================================
+ Hits          917     1098     +181     
+ Misses        348      228     -120     
+ Partials      110       50      -60

Impacted Files	Coverage Δ
query/query.go	97.2% <100%> (+31.47%)	⬆️

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[rnovikovP]

@tfukaya , @xuewindy can you sign our Contributor License Agreement (by clicking the button above) to help us merge your PRs. Thanks for helping us!

[ghost]

Thanks!
I will confirm my company to agree the CLA.
Please wait a moment.

[ghost]

@rnovikovP
I just signed the CLA.
Thanks.

[arvenil]

@xuewindy Could you sign the CLA?