flb_aws_util: added function flb_aws_strftime_precision for time output

[Claych]

---

Enter [N/A] in the box, if an item is not applicable to your change.

Testing
Before we can approve your change; please submit the following in a comment:

• Example configuration file for the change

[INPUT]
    Name                         forward
    Listen                       0.0.0.0
    Port                         24224
[OUTPUT]
    Name                         kinesis_streams
    Match                        *
    region                       us-east-1
    stream                       test-clay-firehose
    time_key                     @timestamp
    time_key_format              %Y-%m-%dT%H:%M:%S.%3N.%L.%L

• Debug log output from testing the change
  Normal time_key_format

[INPUT]
    Name                         forward
    Listen                       0.0.0.0
    Port                         24224

[OUTPUT]
    Name                         kinesis_streams
    Match                        *
    region                       us-east-1
    stream              test-clay-firehose
    time_key                     @timestamp
    time_key_format              %Y-%m-%dT%H:%M:%S.%3N.%L.%L

{"from":"userA","to":"userB","@timestamp":"2023-01-04T00:39:14.250.250161647.250161647.250161647"}
{"from":"userA","to":"userB","@timestamp":"2023-01-04T00:39:14.250.250229597.250229597.250229597"}
{"from":"userA","to":"userB","@timestamp":"2023-01-04T00:39:14.250.250403404.250403404.250403404"}
{"from":"userA","to":"userB","@timestamp":"2023-01-04T00:39:14.251.251213550.251213550.251213550"}
{"from":"userA","to":"userB","@timestamp":"2023-01-04T00:39:14.251.251456260.251456260.251456260"}
{"from":"userA","to":"userB","@timestamp":"2023-01-04T00:39:14.251.251516580.251516580.251516580"}
{"from":"userA","to":"userB","@timestamp":"2023-01-04T00:39:14.251.251573085.251573085.251573085"}
{"from":"userA","to":"userB","@timestamp":"2023-01-04T00:39:14.251.251810073.251810073.251810073"}
{"from":"userA","to":"userB","@timestamp":"2023-01-04T00:39:14.252.252052307.252052307.252052307"}
{"from":"userA","to":"userB","@timestamp":"2023-01-04T00:39:14.252.252310276.252310276.252310276"}
{"from":"userA","to":"userB","@timestamp":"2023-01-04T00:39:14.253.253333330.253333330.253333330"}

Wrong time_key_format

[INPUT]
    Name                         forward
    Listen                       0.0.0.0
    Port                         24224

[OUTPUT]
    Name                         kinesis_streams
    Match                        *
    region                       us-east-1
    stream              test-clay-firehose
    time_key                     @timestamp
    time_key_format              %Y-%m-%dT%H:%M:%S.%3N.%L.%L-%9N-9N~%9N-99N~%99N-99NN~%9%9NN-9NL~%9N%L

fluent-bit log

[2023/01/04 01:05:02] [ info] [output:kinesis_streams:kinesis_streams.0] worker #0 started
[2023/01/04 01:05:19] [error] [output:kinesis_streams:kinesis_streams.0] Failed to add time_key @timestamp to record, test-clay-firehose
[2023/01/04 01:05:19] [error] [output:kinesis_streams:kinesis_streams.0] Failed to add time_key @timestamp to record, test-clay-firehose
[2023/01/04 01:05:19] [error] [output:kinesis_streams:kinesis_streams.0] Failed to add time_key @timestamp to record, test-clay-firehose
[2023/01/04 01:05:19] [error] [output:kinesis_streams:kinesis_streams.0] Failed to add time_key @timestamp to record, test-clay-firehose
[2023/01/04 01:05:19] [error] [output:kinesis_streams:kinesis_streams.0] Failed to add time_key @timestamp to record, test-clay-firehose

{"from":"userA","to":"userB"}
{"from":"userA","to":"userB"}
{"from":"userA","to":"userB"}
{"from":"userA","to":"userB"}
{"from":"userA","to":"userB"}
{"from":"userA","to":"userB"}
{"from":"userA","to":"userB"}
{"from":"userA","to":"userB"}

• Attached Valgrind output that shows no leaks or memory corruption was found

==8834== 
==8834== LEAK SUMMARY:
==8834==    definitely lost: 0 bytes in 0 blocks
==8834==    indirectly lost: 0 bytes in 0 blocks
==8834==      possibly lost: 0 bytes in 0 blocks
==8834==    still reachable: 102,912 bytes in 3,432 blocks
==8834==         suppressed: 0 bytes in 0 blocks
==8834== 
==8834== For lists of detected and suppressed errors, rerun with: -s
==8834== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)

If this is a change to packaging of containers or native binaries then please confirm it works for all targets.

• Attached local packaging test output showing all targets (including any new ones) build.

Documentation

• Documentation required for this feature

fluent/fluent-bit-docs#981 fluent/fluent-bit-docs#980
Backporting

• Backport to latest stable release.

---

Fluent Bit is licensed under Apache 2.0, by submitting this pull request I understand that this code will be released under the terms of that license.

[PettitWesley]

declare variable at top of function not in for loop

[matthewfala]

I get a Segfault with the following test:

[INPUT]
    Name                        dummy
    Tag                         log

[OUTPUT]
    Name                         kinesis_firehose
    Match                        *
    region                       us-west-2
    delivery_stream              firehose-compression-4-0
    time_key                     @timestamp
    time_key_format              %Y-%m-%dT%H:%M:%S.%3N.%L.%L-%9N-9N~%9N-99N~%99N-99NN~%9%9NN-9NL~%9N%L

[matthewfala]

Okay. This looks better. As long as it is well tested, it has my approval!

[PettitWesley]

Please read the comment above this function, it says:

-1 = failure, record not added

We discussed this and agreed we want to still add the record to the buffer, and just not add the timekey. This corresponds with a 0 return value.

[PettitWesley]

Same comment as in firehose

[PettitWesley]

@Claych I am concerned with the testing results:

{"from":"userA","to":"userB","@timestamp":"2022-11-18T04:58:45.649.649094581"}

This came from?

time_key_format              %Y-%m-%dT%H:%M:%S.%3N.%L.%L

How come nanoseconds aren't shown twice at the end of the timestamp above?