Description
A prometheus module for Nest.
Installation
```bash
$ npm install --save @digikare/nestjs-prom prom-client
```
How to use
Import
PromModule into the root
ApplicationModule
```typescript
import { Module } from '@nestjs/common';
import { PromModule } from '@digikare/nestjs-prom';
@Module({
imports:
PromModule.forRoot({
defaultLabels: {
app: 'my_app',
}
}),
})
export class ApplicationModule {}
```
Setup metric
In your module, use
forMetrics() method to define the metrics needed.
```typescript
import { Module } from '@nestjs/common';
import { PromModule, MetricType } from '@digikare/nest-prom';
@Module({
imports:
PromModule.forMetrics([
{
type: MetricType.Counter,
configuration: {
name: 'my_counter',
help: 'my_counter a simple counter',
}
},
{
type: MetricType.Gauge,
configuration: {
name: 'my_gauge',
help: 'my_gauge a simple gauge',
}
},
{
type: MetricType.Histogram,
configuration: {
name: 'my_histogram',
help: 'my_histogram a simple histogram',
}
},
{
type: MetricType.Summary,
configuration: {
name: 'my_summary',
help: 'my_summary a simple summary',
}
}
]),
})
export class MyModule
```
And you can use
@InjectCounterMetric() decorator to get the metrics
```typescript
import { Injectable } from '@nestjs/common';
import {
InjectCounterMetric,
InjectGaugeMetric,
InjectHistogramMetric,
InjectSummaryMetric,
CounterMetric,
GaugeMetric,
HistogramMetric,
SummaryMetric,
} from '@digikare/nest-prom';
@Injectable()
export class MyService {
constructor(
@InjectCounterMetric('my_counter') private readonly _counterMetric: CounterMetric,
@InjectGaugeMetric('my_gauge') private readonly _gaugeMetric: GaugeMetric,
@InjectHistogramMetric('my_histogram') private readonly _histogramMetric: HistogramMetric,
@InjectSummaryMetric('my_summary') private readonly _summaryMetric: SummaryMetric,
) {}
doStuff() {
this._counterMetric.inc();
}
resetCounter() {
this._counterMetric.reset();
}
}
```
Metric endpoint
At the moment, no way to configure the
/metrics endpoint path.
PS: If you have a global prefix, the path will be
{globalPrefix}/metrics for
the moment.
API
PromModule.forRoot() options
withDefaultsMetrics: boolean (default true) enable defaultMetrics provided by prom-client
withDefaultController: boolean (default true) add internal controller to expose /metrics endpoints
useHttpCounterMiddleware: boolean (default false) register httprequeststotal counter
Auth/security
I do not provide any auth/security for
/metrics endpoints.
This is not the aim of this module, but depending of the auth strategy, you can
apply a middleware on
/metrics to secure it.
TODO
- Gauge
- Histogram
- Summary
- Give possibility to custom metric endpoint
- Adding example on how to secure
/metrics endpoint
- secret
- jwt
License
MIT licensed
