[processor/transform] Add option for aggregating metrics with same metric identity (resolving Identity Conflict)

[adam-kiss-sg]

Component(s)

processor/transform

Is your feature request related to a problem? Please describe.

I have metrics produced by spanmetrics processor, which has an attribute for the http status code. I would like to instead have status classes (eg: 2xx, 4xx, 5xx). If i rename the labels of the metrics, it would lead to Identity Conflict

Describe the solution you'd like

I would like to be able to specify how to merge metrics with the same identity after all transformation has run. (eg: sum, mean, min, max).

  transform:
    metrics:
      statements:
        - set(attributes["status_class"], attributes["http.status_code"])
        - replace_match(attributes["status_class"], "2*", "2xx")
        - replace_match(attributes["status_class"], "4*", "4xx")
        - replace_match(attributes["status_class"], "5*", "5xx")
        - keep_keys(attributes, ["net.host.port", "http.method", "http.status_code"])
        - aggregate_same_identity_metrics("sum")

Describe alternatives you've considered

I have looked at metricstransform processor, but i would need to specify all status codes there (eg: from 200 to 299), and also create a group for all of these, eg:

  transform/spanmetrics:                                                                                                 
    metrics:                                                                                                             
      statements:                                                                          
        # workaround to convert http.status_code to string, because metricstransform aggregate_label_values only works with strings
        - set(attributes["http.status_code"], Concat([attributes["http.status_code"]], ""))
  metricstransform/spanmetrics:
    transforms:
      - include: calls_total|latency
        match_type: regexp
        action: update
        operations:
          - action: aggregate_label_values
            label: http.status_code
            aggregated_values: [ 
              "200", "201", "202", "203", "204", "205", "206", "207", "208", "209",
              "210", "211", "212", "213", "214", "215", "216", "217", "218", "219",
              "220", "221", "222", "223", "224", "225", "226", "227", "228", "229",
              "230", "231", "232", "233", "234", "235", "236", "237", "238", "239",
              "240", "241", "242", "243", "244", "245", "246", "247", "248", "249",
              "250", "251", "252", "253", "254", "255", "256", "257", "258", "259",
              "260", "261", "262", "263", "264", "265", "266", "267", "268", "269",
              "270", "271", "272", "273", "274", "275", "276", "277", "278", "279",
              "280", "281", "282", "283", "284", "285", "286", "287", "288", "289",
              "290", "291", "292", "293", "294", "295", "296", "297", "298", "299",
            ]
            new_value: 2xx 
            aggregation_type: sum
          - action: aggregate_label_values
            label: http.status_code
            aggregated_values: [ 
              "400", "401", "402", "403", "404", "405", "406", "407", "408", "409",
              "410", "411", "412", "413", "414", "415", "416", "417", "418", "419",
              "420", "421", "422", "423", "424", "425", "426", "427", "428", "429",
              "430", "431", "432", "433", "434", "435", "436", "437", "438", "439",
              "440", "441", "442", "443", "444", "445", "446", "447", "448", "449",
              "450", "451", "452", "453", "454", "455", "456", "457", "458", "459",
              "460", "461", "462", "463", "464", "465", "466", "467", "468", "469",
              "470", "471", "472", "473", "474", "475", "476", "477", "478", "479",
              "480", "481", "482", "483", "484", "485", "486", "487", "488", "489",
              "490", "491", "492", "493", "494", "495", "496", "497", "498", "499",
            ]
            new_value: 4xx 
            aggregation_type: sum
          - action: aggregate_label_values
            label: http.status_code
            aggregated_values: [ 
              "500", "501", "502", "503", "504", "505", "506", "507", "508", "509",
              "510", "511", "512", "513", "514", "515", "516", "517", "518", "519",
              "520", "521", "522", "523", "524", "525", "526", "527", "528", "529",
              "530", "531", "532", "533", "534", "535", "536", "537", "538", "539",
              "540", "541", "542", "543", "544", "545", "546", "547", "548", "549",
              "550", "551", "552", "553", "554", "555", "556", "557", "558", "559",
              "560", "561", "562", "563", "564", "565", "566", "567", "568", "569",
              "570", "571", "572", "573", "574", "575", "576", "577", "578", "579",
              "580", "581", "582", "583", "584", "585", "586", "587", "588", "589",
              "590", "591", "592", "593", "594", "595", "596", "597", "598", "599",
            ]
            new_value: 5xx 
            aggregation_type: sum

Additional context

I believe this feature could address this issue as well: #16224, but is more flexible then the proposed solution there, as it can be combined with other features of the transform processor:

It would also allow some other use-cases, like:

• combining metrics
• easily dropping labels, or using keep_keys without worrying about metric identity
• using different labels in different envs (dev/prod), without modifying application code

[github-actions]

Pinging code owners:

• processor/transform: @TylerHelmuth @kentquirk @bogdandrutu @evan-bradley

See Adding Labels via Comments if you do not have permissions to add labels yourself.

[github-actions]

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Pinging code owners:

• processor/transform: @TylerHelmuth @kentquirk @bogdandrutu @evan-bradley

See Adding Labels via Comments if you do not have permissions to add labels yourself.

[github-actions]

This issue has been closed as inactive because it has been stale for 120 days with no activity.