feature: finish the CLI logs part

[fuweid]

Signed-off-by: Wei Fu fhfuwei@163.com

Ⅰ. Describe what this PR did

Finish the CLI logs part in the pouch

Ⅱ. Does this pull request fix one issue?

Fixed #1371

Ⅲ. Describe how you did it

Since the API parts has been done, the CLI part is just to fill the logic. However, during the testing, we found the IO issue like #1471 .

Some case maybe fail and it will be flaky case if #1471 doesn't merge.

Ⅳ. Describe how to verify it

➜  pouch run -d busybox sh -c 'for i in $(seq 1 3); do sleep 1; echo hello-$i; done;'
7ba6e5b25b961841145fd8aacaa4d9269bb38ef55519cf74265480326fd779d9
➜  pouch logs --timestamps 7ba6e5b25b961841145fd8aacaa4d9269bb38ef55519cf74265480326fd779d9
2018-06-05T14:05:31.082112571Z hello-1
2018-06-05T14:05:32.084694723Z hello-2
2018-06-05T14:05:33.09511301Z hello-3
➜  pouch logs --since 2018-06-05T14:05:32Z --until 2018-06-05T14:05:32.084694724Z 7ba6e5b25b961841145fd8aacaa4d9269bb38ef55519cf74265480326fd779d9
hello-2
➜  pouch logs --until 2018-06-05T14:05:32.084694724Z 7ba6e5b25b961841145fd8aacaa4d9269bb38ef55519cf74265480326fd779d9
hello-1
hello-2

Ⅴ. Special notes for reviews

[allencloud]

Unfortunately, CI fails with golint, @fuweid :

/go/bin/golint
pkg/utils/utils.go:141:4: should replace numColons -= 1 with numColons--
Makefile:57: recipe for target 'lint' failed

Interesting.

[fuweid]

@allencloud I want to add the make check in the git pre-hook. just reminder haha

[fuweid]

@HusterWan Please help me to check the failed case 😄 thanks

[codecov-io]

Codecov Report

Merging #1472 into master will increase coverage by 24.37%.
The diff coverage is 76.05%.

@@             Coverage Diff             @@
##           master    #1472       +/-   ##
===========================================
+ Coverage    16.5%   40.87%   +24.37%     
===========================================
  Files         210      253       +43     
  Lines       13889    16539     +2650     
===========================================
+ Hits         2292     6760     +4468     
+ Misses      11441     8922     -2519     
- Partials      156      857      +701

Impacted Files	Coverage Δ
cli/logs.go	0% <0%> (ø)	⬆️
daemon/logger/jsonfile/utils.go	71.54% <100%> (+1.54%)	⬆️
pkg/utils/utils.go	88.67% <100%> (+15.62%)	⬆️
client/container_logs.go	76.92% <55.55%> (+76.92%)	⬆️
apis/metrics/metrics.go	100% <0%> (ø)
storage/quota/set_diskquota.go	9.09% <0%> (ø)
cri/stream/httpstream/spdy/upgrade.go	0% <0%> (ø)
pkg/debug/debug.go	22.22% <0%> (ø)
storage/quota/quota.go	12.61% <0%> (ø)
internal/generator.go	100% <0%> (ø)
... and 117 more

[allencloud]

Quite interesting, the test coverage decreases. 😄

[zhuangqh]

If the content don't end with \n like 1\n2\n3\n4, seekOffsetByTailLines(, 2) will return the index of 2. The tail content would be 2\n3\n4. Compared with command tail, echo "1\n2\n3\n4" > a.txt; tail -n2 a.txt is 3\n4.
Does this function works as expected?😁 @fuweid

[fuweid]

this function is only used for the jsonfile log driver. The last line in the file must contain the carriage. So don’t worry about this

[zhuangqh]

haha. I got it. Thanks for your reply at midnight~ @fuweid

[allencloud]

LGTM