Metrics

[spencergibb]

Determine what metrics could be useful and define a strategy for exporting them using boots metrics apis

[mathieufortin01]

As long as a MeterRegistry is available I guess the process of exporting the metrics is delegated to micrometer ?, so no problem there.

Since a filter has access to both request and response, I constructed a simple metrics gateway filter which counts/clocks the requests and exports to Cloudwatch. I dont know if it is the way to go but this works well.

It would be nice to have a configurable metrics filter where different metrics could be added (along with tags/dimensions) mostly from the configuration file only.

One thing I'm struggling with though, is how to handle metrics for "Variable Subsitution" URLs, without duplicating all URLs definitions of the underlying services in the gateway ? I would like 1 metric for GET /users/{id}, not 1 for each user id received (/users/1, /users/2, etc).

[spencergibb]

@mathieufortin01 url's are not a good thing to use since routes can be matched by anything in the request, such as headers, host, & parameters, not just path. The only thing I can think of that would be useful is the route id. This use case calls for descriptive route id's. /cc @jkschneider

[spencergibb]

@mathieufortin01 mind sharing the filter you came up with?

[spencergibb]

By default, we get normal webflux metrics.

For this route I get the following

spencer@:~% http ":8080/actuator/metrics/http.server.requests?tag=uri:/get"
HTTP/1.1 200 OK
Cache-Control: no-cache, no-store, max-age=0, must-revalidate
Content-Type: application/vnd.spring-boot.actuator.v2+json;charset=UTF-8
Expires: 0
Pragma: no-cache
X-Content-Type-Options: nosniff
X-Frame-Options: DENY
X-XSS-Protection: 1 ; mode=block
transfer-encoding: chunked

{
    "availableTags": [
        {
            "tag": "exception",
            "values": [
                "none"
            ]
        },
        {
            "tag": "method",
            "values": [
                "GET"
            ]
        },
        {
            "tag": "status",
            "values": [
                "200"
            ]
        }
    ],
    "measurements": [
        {
            "statistic": "COUNT",
            "value": 2.0
        },
        {
            "statistic": "TOTAL_TIME",
            "value": 5.001693461
        },
        {
            "statistic": "MAX",
            "value": 4.94594301
        }
    ],
    "name": "http.server.requests"
}

If we want more specific metrics, we can address those in a future release.

[ryanjbaxter]

Closed via 972c371