Cherry-pick #18991 to 7.x: Fix translate_sid's empty target field handling

[andrewkroh]

Cherry-pick of PR #18991 to 7.x branch. Original message:

What does this PR do?

The translate_sid processor only requires one of the three target fields to be configured. It should work properly when some of the targets are not set, but it doesn't check if they are empty strings. So it ends up adding target fields that are empty strings to the event (e.g. "": "Group").

Why is it important?

Without this fix, if some target fields were not set then the beat would produce invalid events that cannot be indexed.

Checklist

• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• [ ] I have made corresponding changes to the documentation
• [ ] I have made corresponding change to the default configuration files
• I have added tests that prove my fix is effective or that my feature works
• I have added an entry in CHANGELOG.next.asciidoc or CHANGELOG-developer.next.asciidoc.

Related issues

• Closes [libbeat] translate_sid should skip empty target fields #18990

[elasticmachine]

💚 Build Succeeded

Expand to view the summary

Build stats

• Build Cause: [marc-gr commented: jenkins run tests]

• Start Time: 2020-06-10T11:38:42.975+0000

• Duration: 85 min 10 sec

Test stats 🧪

Test	Results
Failed	0
Passed	6691
Skipped	1069
Total	7760

Steps errors

Expand to view the steps failures

• Name: Report to Codecov

  • Description: curl -sSLo codecov https://codecov.io/bash for i in auditbeat filebeat heartbeat libbeat metricbeat packetbeat winlogbeat journalbeat do FILE="${i}/build/coverage/full.cov" if [ -f "${FILE}" ]; then bash codecov -f "${FILE}" fi done

  • Duration: 2 min 22 sec

  • Start Time: 2020-06-10T12:20:10.440+0000

  • log

[andrewkroh]

run tests

[elasticmachine]

Pinging @elastic/siem (Team:SIEM)

[marc-gr]

jenkins run tests