# FlinkMetrics Receiver

<!-- status autogenerated section -->
| Status        |           |
| ------------- |-----------|
| Stability     | [alpha]: metrics   |
| Distributions | [contrib], [observiq], [sumo] |
| Issues        | [![Open issues](https://img.shields.io/github/issues-search/open-telemetry/opentelemetry-collector-contrib?query=is%3Aissue%20is%3Aopen%20label%3Areceiver%2Fflinkmetrics%20&label=open&color=orange&logo=opentelemetry)](https://github.com/open-telemetry/opentelemetry-collector-contrib/issues?q=is%3Aopen+is%3Aissue+label%3Areceiver%2Fflinkmetrics) [![Closed issues](https://img.shields.io/github/issues-search/open-telemetry/opentelemetry-collector-contrib?query=is%3Aissue%20is%3Aclosed%20label%3Areceiver%2Fflinkmetrics%20&label=closed&color=blue&logo=opentelemetry)](https://github.com/open-telemetry/opentelemetry-collector-contrib/issues?q=is%3Aclosed+is%3Aissue+label%3Areceiver%2Fflinkmetrics) |
| [Code Owners](https://github.com/open-telemetry/opentelemetry-collector-contrib/blob/main/CONTRIBUTING.md#becoming-a-code-owner)    | [@JonathanWamsley](https://www.github.com/JonathanWamsley), [@djaglowski](https://www.github.com/djaglowski) |

[alpha]: https://github.com/open-telemetry/opentelemetry-collector#alpha
[contrib]: https://github.com/open-telemetry/opentelemetry-collector-releases/tree/main/distributions/otelcol-contrib
[observiq]: https://github.com/observIQ/observiq-otel-collector
[sumo]: https://github.com/SumoLogic/sumologic-otel-collector
<!-- end autogenerated section -->

This receiver uses Flink's [REST API](https://nightlies.apache.org/flink/flink-docs-release-1.14/docs/ops/metrics/#rest-api-integration) to collect Jobmanager, Taskmanager, Job, Task and Operator metrics.

## Prerequisites

This receiver supports Apache Flink versions `1.13.6` and `1.14.4`.

By default, authentication is not required. However, [Flink recommends](https://nightlies.apache.org/flink/flink-docs-master/docs/deployment/security/security-ssl/#external--rest-connectivity) using a “side car proxy” that Binds the REST endpoint to the loopback interface and to start a REST proxy that authenticates and forwards the request to Flink.

[SSL](https://nightlies.apache.org/flink/flink-docs-master/docs/deployment/security/security-ssl/#external--rest-connectivity) can be enabled with the following REST endpoint [options](https://nightlies.apache.org/flink/flink-docs-master/docs/deployment/security/security-ssl/#rest-endpoints-external-connectivity) for external connectivity and have a self signed certificate or be self signed.

## Configuration

The following settings are optional:

- `endpoint` (default: `http://localhost:15672`): The URL of the node to be monitored.
- `collection_interval` (default = `10s`): This receiver collects metrics on an interval. Valid time units are `ns`, `us` (or `µs`), `ms`, `s`, `m`, `h`.
- `tls` (defaults defined [here](https://github.com/open-telemetry/opentelemetry-collector/blob/main/config/configtls/README.md)): TLS control. By default insecure settings are rejected and certificate verification is on.
- `initial_delay` (default = `1s`): defines how long this receiver waits before starting.

### Example Configuration

```yaml
receivers:
  flinkmetrics:
    endpoint: http://localhost:8081
    collection_interval: 10s
```

The full list of settings exposed for this receiver are documented [here](./config.go) with detailed sample configurations [here](./testdata/config.yaml). TLS config is documented further under the [opentelemetry collector's configtls package](https://github.com/open-telemetry/opentelemetry-collector/blob/main/config/configtls/README.md).

## Metrics

Details about the metrics produced by this receiver can be found in [metadata.yaml](./metadata.yaml)