# OpenTelemetry

Requirements:

- docker-compose

## Prepare setup

Create a `docker-compose.yaml` and `otel-collector-config.yml` file as seen below in a folder.

```yaml title="docker-compose.yaml"
name: renovate-otel-demo

services:
  # Jaeger for storing traces
  jaeger:
    image: jaegertracing/jaeger:2.20.0
    ports:
      - '16686:16686' # Web UI
      - '4317' # OTLP gRPC
      - '4318' # OTLP HTTP

  # Prometheus for storing metrics
  prometheus:
    image: prom/prometheus:v3.14.0
    ports:
      - '9090:9090' # Web UI
      - '4318' # OTLP HTTP
    command:
      - --web.enable-otlp-receiver
      # Mirror these flags from the Dockerfile, because `command` overwrites the default flags.
      # https://github.com/prometheus/prometheus/blob/5b5fee08af4c73230b2dae35964816f7b3c29351/Dockerfile#L23-L24
      - --config.file=/etc/prometheus/prometheus.yml
      - --storage.tsdb.path=/prometheus

  otel-collector:
    # Using the Contrib version to access the spanmetrics connector.
    # If you don't need the spanmetrics connector, you can use the standard version
    image: otel/opentelemetry-collector-contrib:0.159.0
    volumes:
      - ./otel-collector-config.yml:/etc/otelcol-contrib/config.yaml
    ports:
      - '4318:4318' # OTLP HTTP ( exposed to the host )
      - '4317:4317' # OTLP gRPC ( exposed to the host )
    depends_on:
      - jaeger
      - prometheus
```

```yaml title="otel-collector-config.yml"
receivers:
  otlp:
    protocols:
      grpc:
        endpoint: 0.0.0.0:4317
      http:
        endpoint: 0.0.0.0:4318

exporters:
  otlp/jaeger:
    endpoint: jaeger:4317
    tls:
      insecure: true
  otlphttp/prometheus:
    endpoint: http://prometheus:9090/api/v1/otlp
  debug:
  # verbosity: normal

connectors:
  spanmetrics:
    histogram:
      exponential:
    dimensions:
      - name: http.method
        default: GET
      - name: http.status_code
      - name: http.host
    dimensions_cache_size: 1000
    aggregation_temporality: 'AGGREGATION_TEMPORALITY_CUMULATIVE'
    exemplars:
      enabled: true

processors:
  batch:

extensions:
  health_check:
  pprof:
  zpages:

service:
  extensions: [pprof, zpages, health_check]
  pipelines:
    traces:
      receivers: [otlp]
      exporters:
        - otlp/jaeger
        # Send traces to connector for metrics calculation
        - spanmetrics
        # Enable debug exporter to see traces in the logs
        #- debug
      processors: [batch]

    metrics:
      receivers:
        - otlp # Receive metrics from Renovate.
        - spanmetrics # Receive metrics calculated by the spanmetrics connector.
      processors: [batch]
      exporters:
        - otlphttp/prometheus
        # Enable debug exporter to see metrics in the logs
        # - debug
```

Start setup using this command inside the folder containing the files created in the earlier steps:

```
docker-compose up
```

This command will start:

- an [OpenTelemetry Collector](https://github.com/open-telemetry/opentelemetry-collector-contrib)
- an instance of [Jaeger for traces](https://www.jaegertracing.io/)
- and [Prometheus](https://prometheus.io/)

Jaeger will be now reachable under [http://localhost:16686](http://localhost:16686).

## Run Renovate with OpenTelemetry

To start Renovate with OpenTelemetry enabled run following command, after pointing to your `config.js` config file:

```
docker run \
  --rm \
  --network renovate-otel-demo_default \
  -e OTEL_EXPORTER_OTLP_ENDPOINT=http://otel-collector:4318 \
  -v "/path/to/your/config.js:/usr/src/app/config.js" \
  renovate/renovate:latest
```

You should now see `trace_id` and `span_id` fields in the logs.

```
 INFO: Repository finished (repository=org/example)
       "durationMs": 5574,
       "trace_id": "f9a4c33852333fc2a0fbdc163100c987",
       "span_id": "4ac1323eeaee
```

### Traces

Open now Jaeger under [http://localhost:16686](http://localhost:16686).

You should now be able to pick `renovate` under in the field `service` field.

![service picker](../assets/images/opentelemetry_pick_service.png)

Select `Find Traces` to search for all Renovate traces and then select one of the found traces to open the trace view.

![pick trace](../assets/images/opentelemetry_choose_trace.png)

You should be able to see now the full trace view which shows more information about what is happening, such as HTTP requests, execution of commands or Git operations, and how long Renovate takes to process a given branch:

![A screenshot of the Jaeger OpenTelemetry tracing UI, which shows an in-depth tracing view of a Renovate run against a single repository. The trace view shows the Renovate "splits", i.e. `init`, `extract`, `lookup` and `update` shown, with a view of how long each of the splits take overall. The trace view also shows HTTP calls, calls to the `git` command-line tools, some function names like `extractAllDependencies`, package manager names like `composer` or `github-actions` under the `extract` and `lookup` splits, and general execution of commands (prefixed by `rawExec:`. The view also shows that under the `update` split, there is a trace per branch, so we can see that the `renovate/actions-checkout-6.x` took less time to process than the `renovate/phpstan-phpstan-2.x-lockfile` branch.](../assets/images/opentelemetry_trace_viewer.png)

### Metrics

Additional to the received traces some metrics are calculated.
This is achieved using the [spanmetrics connector](https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/connector/spanmetricsconnector).
The previously implemented setup will produce following metrics, which pushed to [Prometheus](http://localhost:9090):

```
### Example of internal spans
traces_span_metrics_calls_total{http_method="GET", job="renovatebot.com/renovate", service_name="renovate", span_kind="SPAN_KIND_INTERNAL", span_name="repository", status_code="STATUS_CODE_UNSET"} 2
traces_span_metrics_calls_total{http_method="GET", job="renovatebot.com/renovate", service_name="renovate", span_kind="SPAN_KIND_INTERNAL", span_name="run", status_code="STATUS_CODE_UNSET"} 2

### Example of http calls from Renovate to external services
traces_span_metrics_calls_total{http_host="api.github.com:443", http_method="POST", http_status_code="200", job="renovatebot.com/renovate", service_name="renovate", span_kind="SPAN_KIND_CLIENT", span_name="POST", status_code="STATUS_CODE_UNSET"} 4


### Example histogram metrics
traces_span_metrics_duration_milliseconds_bucket{http_method="GET", job="renovatebot.com/renovate", le="8", service_name="renovate", span_kind="SPAN_KIND_INTERNAL", span_name="repository", status_code="STATUS_CODE_UNSET"} 0
...
traces_span_metrics_duration_milliseconds_bucket{http_method="GET", job="renovatebot.com/renovate", le="2000", service_name="renovate", span_kind="SPAN_KIND_INTERNAL", span_name="repository", status_code="STATUS_CODE_UNSET"} 0
traces_span_metrics_duration_milliseconds_bucket{http_method="GET", job="renovatebot.com/renovate", le="5000", service_name="renovate", span_kind="SPAN_KIND_INTERNAL", span_name="repository", status_code="STATUS_CODE_UNSET"} 1
traces_span_metrics_duration_milliseconds_bucket{http_method="GET", job="renovatebot.com/renovate", le="15000", service_name="renovate", span_kind="SPAN_KIND_INTERNAL", span_name="repository", status_code="STATUS_CODE_UNSET"} 1
traces_span_metrics_duration_milliseconds_bucket{http_method="GET", job="renovatebot.com/renovate", le="10000", service_name="renovate", span_kind="SPAN_KIND_INTERNAL", span_name="repository", status_code="STATUS_CODE_UNSET"} 1
traces_span_metrics_duration_milliseconds_bucket{http_method="GET", job="renovatebot.com/renovate", le="+Inf", service_name="renovate", span_kind="SPAN_KIND_INTERNAL", span_name="repository", status_code="STATUS_CODE_UNSET"} 1

traces_span_metrics_duration_milliseconds_sum{http_method="GET", job="renovatebot.com/renovate", service_name="renovate", span_kind="SPAN_KIND_INTERNAL", span_name="repository", status_code="STATUS_CODE_UNSET"} 4190.694209
traces_span_metrics_duration_milliseconds_count{http_method="GET", job="renovatebot.com/renovate", service_name="renovate", span_kind="SPAN_KIND_INTERNAL", span_name="repository", status_code="STATUS_CODE_UNSET"} 1
```

The [spanmetrics connector](https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/connector/spanmetricsconnector) creates two sets of metrics.

#### Calls metric

At first there are the `traces_span_metrics_calls_total` metrics.
These metrics show how often _specific_ trace spans have been observed.

For example:

- `traces_span_metrics_calls_total{http_method="GET", job="renovatebot.com/renovate", service_name="renovate", span_kind="SPAN_KIND_INTERNAL", span_name="repositories", status_code="STATUS_CODE_UNSET"} 2` signals that 2 repositories have been renovated.
- `traces_span_metrics_calls_total{http_method="GET", job="renovatebot.com/renovate", service_name="renovate", span_kind="SPAN_KIND_INTERNAL", span_name="run", status_code="STATUS_CODE_UNSET"} 1` represents how often Renovate has been run.

If we combine this using the PrometheusQueryLanguage ( PromQL ), we can calculate the average count of repositories each Renovate run handles.

```
traces_span_metrics_calls_total{span_name="repository",service_name="renovate"} / traces_span_metrics_calls_total{span_name="run",service_name="renovate"}
```

These metrics are generated for HTTP call spans too:

```yaml
traces_span_metrics_calls_total{http_host="prometheus-community.github.io:443", http_method="GET", http_status_code="200", job="renovatebot.com/renovate", service_name="renovate", span_kind="SPAN_KIND_CLIENT", span_name="GET", status_code="STATUS_CODE_UNSET"} 5
```

#### Latency buckets

The second class of metrics exposed are the latency-focused buckets, that allow creating [heatmaps](https://grafana.com/docs/grafana/latest/basics/intro-histograms/#heatmaps).
A request is added to a backed if the latency is bigger than the bucket value (`le`). `request_duration => le`

As an example if we receive a request which need `1.533s` to complete get following metrics:

```
traces_span_metrics_duration_milliseconds_bucket{http_host="api.github.com:443",le="0.1"} 0
traces_span_metrics_duration_milliseconds_bucket{http_host="api.github.com:443",le="1"} 0
traces_span_metrics_duration_milliseconds_bucket{http_host="api.github.com:443",le="2"} 1
traces_span_metrics_duration_milliseconds_bucket{http_host="api.github.com:443",le="6"} 1
traces_span_metrics_duration_milliseconds_bucket{http_host="api.github.com:443",le="10"} 1
traces_span_metrics_duration_milliseconds_bucket{http_host="api.github.com:443",le="100"} 1
traces_span_metrics_duration_milliseconds_bucket{http_host="api.github.com:443",le="250"} 1
traces_span_metrics_duration_milliseconds_bucket{http_host="api.github.com:443",le="9.223372036854775e+12"} 1
traces_span_metrics_duration_milliseconds_bucket{http_host="api.github.com:443",le="+Inf"} 1
traces_span_metrics_duration_milliseconds_sum{http_host="api.github.com:443"} 1.533
traces_span_metrics_duration_milliseconds_count{http_host="api.github.com:443"} 1
```

Now we have another request which this time takes 10s to complete:

```
traces_span_metrics_duration_milliseconds_bucket{http_host="api.github.com:443",le="0.1"} 0
traces_span_metrics_duration_milliseconds_bucket{http_host="api.github.com:443",le="1"} 0
traces_span_metrics_duration_milliseconds_bucket{http_host="api.github.com:443",le="2"} 1
traces_span_metrics_duration_milliseconds_bucket{http_host="api.github.com:443",le="6"} 1
traces_span_metrics_duration_milliseconds_bucket{http_host="api.github.com:443",le="10"} 2
traces_span_metrics_duration_milliseconds_bucket{http_host="api.github.com:443",le="100"} 2
traces_span_metrics_duration_milliseconds_bucket{http_host="api.github.com:443",le="250"} 2
traces_span_metrics_duration_milliseconds_bucket{http_host="api.github.com:443",le="9.223372036854775e+12"} 2
traces_span_metrics_duration_milliseconds_bucket{http_host="api.github.com:443",le="+Inf"} 2
traces_span_metrics_duration_milliseconds_sum{http_host="api.github.com:443"} 11.533
traces_span_metrics_duration_milliseconds_count{http_host="api.github.com:443"} 2
```

More about the functionality can be found on the Prometheus page for [metric types](https://prometheus.io/docs/concepts/metric_types/#histogram).