filestream: validate input id on startup

[AndersonQ]

During startup filebeat now validates the filestream inputs and fails to start if there are inputs without ID or with duplicated IDs. Duplicated IDs might cause data duplication therefore now it's mandatory to have unique and non-empty ID for each filestream input.

Proposed commit message

filestream: validate input id on startup

During startup filebeat now validates the filestream inputs and fails to start if there are inputs without ID or with duplicated IDs. Duplicated IDs might cause data duplication therefore now it's mandatory to have unique and non-empty ID for each filestream input. 

Checklist

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

Disruptive User Impact

Impact: Users who have not configured unique IDs for their filestream inputs will need to update their configurations to include unique IDs for each input. Failure to do so will prevent Filebeat from starting.

Previously: Filebeat would only log an error if filestream would find inputs had missing or duplicated IDs, potentially leading to data duplication.

Now: Filebeat will fail to start if any filestream input lacks an ID or has a duplicated ID.

How to test this PR locally

• build filebeat

  cd filebeat
  go build .

• use the following as filebeat.yml

  
  filebeat.inputs:
  - type: filestream
  enabled: true
  paths:
    - /tmp/noID-1/*.log
  - type: filestream
  enabled: true
  paths:
    - /tmp/noID-2/*.log
  - type: filestream
  id: duplicated-id
  enabled: true
  paths:
    - /tmp/duplicated-id-1/*.log
  - type: filestream
  id: duplicated-id
  enabled: true
  paths:
    - /tmp/duplicated-id-2/*.log

output.discard.enabled: true logging: level: info metrics: enabled: false

- run filebeat:
```shell
./filebeat -e 2>&1 | grep message

verify filebeat:

• will exit with error
• will produce a log with all the invalid input configuration:

  {"@timestamp":"2024-11-21T15:38:05.974+0100","log.level":"error","message":"filestream inputs with invalid IDs","log.logger":"filestream","log.origin":{"function":"github.com/elastic/beats/v7/filebeat/input/filestream.ValidateInputIDs","file.name":"filestream/config.go","file.line":187},"service.name":"filebeat","inputs":[{"enabled":true,"paths":["/tmp/noID-1/*.log"],"type":"filestream"},{"enabled":true,"paths":["/tmp/noID-2/*.log"],"type":"filestream"},{"enabled":true,"id":"duplicated-id","paths":["/tmp/duplicated-id-1/*.log"],"type":"filestream"},{"enabled":true,"id":"duplicated-id","paths":["/tmp/duplicated-id-2/*.log"],"type":"filestream"}],"ecs.version":"1.6.0"}

• will produce a log pointing out the issues:

  {"@timestamp":"2024-11-21T15:38:05.974+0100","log.level":"error","message":"invalid filestream configuration: filestream inputs validation error: input without ID, found filestream inputs with duplicated IDs: duplicated-id","log.origin":{"function":"github.com/elastic/beats/v7/filebeat/beater.(*Filebeat).Run","file.name":"beater/filebeat.go","file.line":297},"service.name":"filebeat","ecs.version":"1.6.0"}

Related issues

• Closes #40540

Logs

{"@timestamp":"2024-11-21T15:38:05.974+0100","log.level":"info","message":"filebeat start running.","log.origin":{"function":"github.com/elastic/beats/v7/libbeat/cmd/instance.(*Beat).launch","file.name":"instance/beat.go","file.line":770},"service.name":"filebeat","ecs.version":"1.6.0"}
{"@timestamp":"2024-11-21T15:38:05.974+0100","log.level":"error","message":"filestream inputs with invalid IDs","log.logger":"filestream","log.origin":{"function":"github.com/elastic/beats/v7/filebeat/input/filestream.ValidateInputIDs","file.name":"filestream/config.go","file.line":187},"service.name":"filebeat","inputs":[{"enabled":true,"paths":["/tmp/noID-1/*.log"],"type":"filestream"},{"enabled":true,"paths":["/tmp/noID-2/*.log"],"type":"filestream"},{"enabled":true,"id":"duplicated-id","paths":["/tmp/duplicated-id-1/*.log"],"type":"filestream"},{"enabled":true,"id":"duplicated-id","paths":["/tmp/duplicated-id-2/*.log"],"type":"filestream"}],"ecs.version":"1.6.0"}
{"@timestamp":"2024-11-21T15:38:05.974+0100","log.level":"error","message":"invalid filestream configuration: filestream inputs validation error: input without ID, found filestream inputs with duplicated IDs: duplicated-id","log.origin":{"function":"github.com/elastic/beats/v7/filebeat/beater.(*Filebeat).Run","file.name":"beater/filebeat.go","file.line":297},"service.name":"filebeat","ecs.version":"1.6.0"}
{"@timestamp":"2024-11-21T15:38:05.974+0100","log.level":"info","message":"filebeat stopped.","log.origin":{"function":"github.com/elastic/beats/v7/libbeat/cmd/instance.(*Beat).launch","file.name":"instance/beat.go","file.line":779},"service.name":"filebeat","ecs.version":"1.6.0"}
{"@timestamp":"2024-11-21T15:38:05.974+0100","log.level":"error","message":"Exiting: filestream inputs validation error: input without ID, found filestream inputs with duplicated IDs: duplicated-id","log.origin":{"function":"github.com/elastic/beats/v7/libbeat/cmd/instance.handleError","file.name":"instance/beat.go","file.line":1594},"service.name":"filebeat","ecs.version":"1.6.0"}

[mergify[bot]]

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• The upcoming major version of the Elastic Stack
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[mergify[bot]]

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[elasticmachine]

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