feat: replace debug log with fmt package.

[appleboy]

fix #829

remove log.SetFlags(0)

[codecov]

Codecov Report

Merging #1560 into master will decrease coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1560      +/-   ##
==========================================
- Coverage   99.06%   99.05%   -0.01%     
==========================================
  Files          39       39              
  Lines        1915     1913       -2     
==========================================
- Hits         1897     1895       -2     
  Misses         14       14              
  Partials        4        4

Impacted Files	Coverage Δ
debug.go	95% <100%> (-0.24%)	⬇️

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[codecov]

Codecov Report

Merging #1560 into master will decrease coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1560      +/-   ##
==========================================
- Coverage   99.06%   99.05%   -0.01%     
==========================================
  Files          39       39              
  Lines        1915     1913       -2     
==========================================
- Hits         1897     1895       -2     
  Misses         14       14              
  Partials        4        4

Impacted Files	Coverage Δ
debug.go	95% <100%> (-0.24%)	⬇️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
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[codecov]

Codecov Report

Merging #1560 into master will decrease coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1560      +/-   ##
==========================================
- Coverage   99.06%   99.05%   -0.01%     
==========================================
  Files          39       39              
  Lines        1915     1913       -2     
==========================================
- Hits         1897     1895       -2     
  Misses         14       14              
  Partials        4        4

Impacted Files	Coverage Δ
debug.go	95% <100%> (-0.24%)	⬇️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update b27b702...3d606cb. Read the comment docs.

[codecov]

Codecov Report

Merging #1560 into master will decrease coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1560      +/-   ##
==========================================
- Coverage   99.06%   99.05%   -0.01%     
==========================================
  Files          39       39              
  Lines        1915     1913       -2     
==========================================
- Hits         1897     1895       -2     
  Misses         14       14              
  Partials        4        4

Impacted Files	Coverage Δ
debug.go	95% <100%> (-0.24%)	⬇️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update b27b702...3d606cb. Read the comment docs.

[codecov]

Codecov Report

Merging #1560 into master will decrease coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1560      +/-   ##
==========================================
- Coverage   99.06%   99.05%   -0.01%     
==========================================
  Files          39       39              
  Lines        1915     1913       -2     
==========================================
- Hits         1897     1895       -2     
  Misses         14       14              
  Partials        4        4

Impacted Files	Coverage Δ
debug.go	95% <100%> (-0.24%)	⬇️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update b27b702...3d606cb. Read the comment docs.

[thinkerou]

LGTM

[philippgille]

@appleboy This leads to logging to stdout instead of stderr, right? That would be a big change. Is this wanted?

[appleboy]

@philippgille just change the output from log to fmt package. you can see the changes of debug.go

[philippgille]

@appleboy: Yes I saw that, that's exactly what I mean. fmt prints to stdout, log prints to stderr.

Some people might in the past have piped stderr into file x and stdout into file y, now when updating gin the files don't contain their expected logs anymore, which is why it's a breaking change.

For access logs stdout makes sense. For errors, stderr might be a better fit. And users should be made aware of the change in Gin.

[philippgille]

@thinkerou what do you think about the change of general logging from stderr to stdout?

[giulianobr]

Hey @appleboy, this change is breaking App Engine local development server to work properly. Is possible to revert to use the log instead of fmt ?

thanks

[appleboy]

@giulianobr @philippgille Please help to review the new PR. #1571

[appleboy]

@philippgille #1571 already merged.