fix(enrichment tables): properly enable memory enrichment table for vector tap

[esensar]

Summary

Source/sink from memory enrichment tables were not visible to vector tap. This PR addresses that.

Vector configuration

api:
  enabled: true
  address: "0.0.0.0:8686"

enrichment_tables:
  memory_table:
    type: memory
    ttl: 10
    flush_interval: 5
    inputs: ["cache_generator"]
    source_config:
       source_key: "memory_table_source"
       export_expired_items: true

sources:
  demo_logs_test:
    type: "demo_logs"
    format: "json"

transforms:
  demo_logs_processor:
    type: "remap"
    inputs: ["demo_logs_test"]
    source: |
      . = parse_json!(.message)
      user_id = get!(., path: ["user-identifier"])

      # Look for existing value in the table, using "user-identifier" as key
      existing, err = get_enrichment_table_record("memory_table", { "key": user_id })

      if err == null {
        . = existing.value
        .source = "cache"
      } else {
        .referer = parse_url!(.referer)
        .referer.host = encode_punycode!(.referer.host)
        .source = "transform"
      }

  cache_generator:
    type: "remap"
    inputs: ["demo_logs_processor"]
    source: |
      existing, err = get_enrichment_table_record("memory_table", { "key": get!(., path: ["user-identifier"]) })
      if err != null {
        data = .
        . = set!(value: {}, path: [get!(data, path: ["user-identifier"])], data: data)
      } else {
        . = {}
      }

# We can observe that after some time data will be dumped to console from the cache
sinks:
  console:
    inputs: ["memory_table_source.expired"]
    target: "stdout"
    type: "console"
    encoding:
      codec: "json"

How did you test this PR?

Ran vector with the configuration above and then ran vector tap:

vector tap --outputs-of memory_table_source.expired

vector tap --inputs-of console

And saw the events out of these components. Previously, these 2 commands returned:

[tap] Pattern 'console' failed to match: will retry on configuration reload.

Change Type

• Bug fix
• New feature
• Non-functional (chore, refactoring, docs)
• Performance

Is this a breaking change?

• Yes
• No

Does this PR include user facing changes?

• Yes. Please add a changelog fragment based on our guidelines.
• No. A maintainer will apply the no-changelog label to this PR.

Notes

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