Adds Micrometer Tracing Example

[codefromthecrypt]

This is the exact same project as webflux5-sleuth, except for micrometer. As always, the style is intentionally like other projects here for easy maintenance, even if it isn't how start.spring.io would do it.

This is more glitchy that sleuth.. for example, the log correlation doesn't work, and some properties are missing. It is also rev-locked until the next release of micrometer. That said, it performs the basics, and is a good start!

[codefromthecrypt]

notes

[codefromthecrypt]

normally I add a 'Trace Instrumentation' section with links as you can see above, but this time, I have no idea where they are! Also, I don't see any canonical page on properties in docs, so I'm referencing the java type directly.

[codefromthecrypt]

had to parameterize this as spring boot requires minimal JRE 17.. the first project to require this.

[codefromthecrypt]

I hope log correlation isn't a w3c only thing.. I perused a bunch of github issues and seems people have been steered towards w3c, but I don't know if that's just because maintainers like it more, or if logic hasn't been stitched together to make normal brave work like before (even spring 2.5 can do this). @shakuzen if you know the scoop lemme know!

[codefromthecrypt]

I'm probably missing something as it seems like no one would want to trace /health by default, and especially not have a way to disable it..

[codefromthecrypt]

For the curious, the data collected is a lot more chatty as it doesn't use brave's http data collection policy. So, basically the bridge isn't going to be able to conform data like native brave does, and avoid things like empty tags for "not exception" etc, or basically use any of the brave tagging functions.

curl -s localhost:9411/api/v2/trace/65c2398c3dd7d31bdb073f203574eff6|jq .
[
  {
    "traceId": "65c2398c3dd7d31bdb073f203574eff6",
    "parentId": "db073f203574eff6",
    "id": "004c6b75a8173964",
    "kind": "CLIENT",
    "name": "http get",
    "timestamp": 1707227532574300,
    "duration": 125911,
    "localEndpoint": {
      "serviceName": "frontend",
      "ipv4": "192.168.106.1"
    },
    "tags": {
      "client.name": "127.0.0.1",
      "exception": "none",
      "http.url": "http://127.0.0.1:9000/api",
      "method": "GET",
      "outcome": "SUCCESS",
      "status": "200",
      "uri": "/api"
    }
  },
  {
    "traceId": "65c2398c3dd7d31bdb073f203574eff6",
    "id": "db073f203574eff6",
    "kind": "SERVER",
    "name": "http get /",
    "timestamp": 1707227532559293,
    "duration": 143467,
    "localEndpoint": {
      "serviceName": "frontend",
      "ipv4": "192.168.106.1"
    },
    "tags": {
      "exception": "none",
      "http.url": "/",
      "method": "GET",
      "outcome": "SUCCESS",
      "status": "200",
      "uri": "/"
    }
  },
  {
    "traceId": "65c2398c3dd7d31bdb073f203574eff6",
    "parentId": "004c6b75a8173964",
    "id": "a6c2578318da548d",
    "kind": "SERVER",
    "name": "http get /api",
    "timestamp": 1707227532672168,
    "duration": 24146,
    "localEndpoint": {
      "serviceName": "backend",
      "ipv4": "192.168.106.1"
    },
    "tags": {
      "exception": "none",
      "http.url": "/api",
      "method": "GET",
      "outcome": "SUCCESS",
      "status": "200",
      "uri": "/api"
    }
  }
]

[codefromthecrypt]

Here's an example of the canonical brave trace, using the armeria example. Armeria adds more timing annotations, but the tags are standard and can be modified uniformly as necessary, like all the others, with brave's HttpTracing type:

$ curl -s localhost:9411/api/v2/trace/ca91e1a961286b00|jq .
[
  {
    "traceId": "ca91e1a961286b00",
    "parentId": "32ca56351b2e40ed",
    "id": "66bf704f516a5e6b",
    "kind": "SERVER",
    "name": "get /api",
    "timestamp": 1707228075240926,
    "duration": 3438,
    "localEndpoint": {
      "serviceName": "backend",
      "ipv4": "192.168.106.1"
    },
    "remoteEndpoint": {
      "ipv4": "127.0.0.1",
      "port": 60553
    },
    "annotations": [
      {
        "timestamp": 1707228075241119,
        "value": "wr"
      },
      {
        "timestamp": 1707228075243588,
        "value": "ws"
      }
    ],
    "tags": {
      "http.method": "GET",
      "http.path": "/api"
    }
  },
  {
    "traceId": "ca91e1a961286b00",
    "parentId": "ca91e1a961286b00",
    "id": "32ca56351b2e40ed",
    "kind": "CLIENT",
    "name": "get",
    "timestamp": 1707228075236792,
    "duration": 7889,
    "localEndpoint": {
      "serviceName": "frontend",
      "ipv4": "192.168.106.1"
    },
    "remoteEndpoint": {
      "serviceName": "backend",
      "ipv4": "127.0.0.1",
      "port": 9000
    },
    "annotations": [
      {
        "timestamp": 1707228075241134,
        "value": "ws"
      },
      {
        "timestamp": 1707228075244181,
        "value": "wr"
      }
    ],
    "tags": {
      "http.method": "GET",
      "http.path": "/api"
    }
  },
  {
    "traceId": "ca91e1a961286b00",
    "id": "ca91e1a961286b00",
    "kind": "SERVER",
    "name": "get /",
    "timestamp": 1707228075236174,
    "duration": 9511,
    "localEndpoint": {
      "serviceName": "frontend",
      "ipv4": "192.168.106.1"
    },
    "annotations": [
      {
        "timestamp": 1707228075236255,
        "value": "wr"
      },
      {
        "timestamp": 1707228075245259,
        "value": "ws"
      }
    ],
    "tags": {
      "http.method": "GET",
      "http.path": "/"
    }
  }
]

[codefromthecrypt]

Thanks for the look @anuraaga!

@shakuzen any notes you may have you can either tell me or raise a PR. We need to bump this soon anyway on the next micrometer release to unlock the brave version.