mirror of
https://github.com/ClusterCockpit/cc-metric-collector.git
synced 2024-11-10 12:37:25 +01:00
109 lines
3.6 KiB
Markdown
109 lines
3.6 KiB
Markdown
# CCMetric sinks
|
|
|
|
This folder contains the SinkManager and sink implementations for the cc-metric-collector.
|
|
|
|
# Available sinks:
|
|
- [`stdout`](./stdoutSink.md): Print all metrics to `stdout`, `stderr` or a file
|
|
- [`http`](./httpSink.md): Send metrics to an HTTP server as POST requests
|
|
- [`influxdb`](./influxSink.md): Send metrics to an [InfluxDB](https://www.influxdata.com/products/influxdb/) database
|
|
- [`influxasync`](./influxAsyncSink.md): Send metrics to an [InfluxDB](https://www.influxdata.com/products/influxdb/) database with non-blocking write API
|
|
- [`nats`](./natsSink.md): Publish metrics to the [NATS](https://nats.io/) network overlay system
|
|
- [`ganglia`](./gangliaSink.md): Publish metrics in the [Ganglia Monitoring System](http://ganglia.info/) using the `gmetric` CLI tool
|
|
- [`libganglia`](./libgangliaSink.md): Publish metrics in the [Ganglia Monitoring System](http://ganglia.info/) directly using `libganglia.so`
|
|
- [`prometeus`](./prometheusSink.md): Publish metrics for the [Prometheus Monitoring System](https://prometheus.io/)
|
|
|
|
# Configuration
|
|
|
|
The configuration file for the sinks is a list of configurations. The `type` field in each specifies which sink to initialize.
|
|
|
|
```json
|
|
[
|
|
"mystdout" : {
|
|
"type" : "stdout",
|
|
"meta_as_tags" : [
|
|
"unit"
|
|
]
|
|
},
|
|
"metricstore" : {
|
|
"type" : "http",
|
|
"host" : "localhost",
|
|
"port" : "4123",
|
|
"database" : "ccmetric",
|
|
"password" : "<jwt token>"
|
|
}
|
|
]
|
|
```
|
|
|
|
|
|
|
|
|
|
# Contributing own sinks
|
|
A sink contains five functions and is derived from the type `sink`:
|
|
* `Init(name string, config json.RawMessage) error`
|
|
* `Write(point CCMetric) error`
|
|
* `Flush() error`
|
|
* `Close()`
|
|
* `New<Typename>(name string, config json.RawMessage) (Sink, error)` (calls the `Init()` function)
|
|
|
|
The data structures should be set up in `Init()` like opening a file or server connection. The `Write()` function writes/sends the data. For non-blocking sinks, the `Flush()` method tells the sink to drain its internal buffers. The `Close()` function should tear down anything created in `Init()`.
|
|
|
|
Finally, the sink needs to be registered in the `sinkManager.go`. There is a list of sinks called `AvailableSinks` which is a map (`sink_type_string` -> `pointer to sink interface`). Add a new entry with a descriptive name and the new sink.
|
|
|
|
## Sample sink
|
|
|
|
```go
|
|
package sinks
|
|
|
|
import (
|
|
"encoding/json"
|
|
"log"
|
|
lp "github.com/ClusterCockpit/cc-metric-collector/internal/ccMetric"
|
|
)
|
|
|
|
type SampleSinkConfig struct {
|
|
defaultSinkConfig // defines JSON tags for 'name' and 'meta_as_tags'
|
|
}
|
|
|
|
type SampleSink struct {
|
|
sink // declarate 'name' and 'meta_as_tags'
|
|
config StdoutSinkConfig // entry point to the SampleSinkConfig
|
|
}
|
|
|
|
// Initialize the sink by giving it a name and reading in the config JSON
|
|
func (s *SampleSink) Init(name string, config json.RawMessage) error {
|
|
s.name = fmt.Sprintf("SampleSink(%s)", name) // Always specify a name here
|
|
// Read in the config JSON
|
|
if len(config) > 0 {
|
|
err := json.Unmarshal(config, &s.config)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// Code to submit a single CCMetric to the sink
|
|
func (s *SampleSink) Write(point lp.CCMetric) error {
|
|
log.Print(point)
|
|
return nil
|
|
}
|
|
|
|
// If the sink uses batched sends internally, you can tell to flush its buffers
|
|
func (s *SampleSink) Flush() error {
|
|
return nil
|
|
}
|
|
|
|
|
|
// Close sink: close network connection, close files, close libraries, ...
|
|
func (s *SampleSink) Close() {}
|
|
|
|
|
|
// New function to create a new instance of the sink
|
|
func NewSampleSink(name string, config json.RawMessage) (Sink, error) {
|
|
s := new(SampleSink)
|
|
err := s.Init(name, config)
|
|
return s, err
|
|
}
|
|
|
|
```
|