2021-12-21 17:47:58 +01:00

100 lines
2.9 KiB
Markdown

# CCMetric sinks
This folder contains the SinkManager and sink implementations for the cc-metric-collector.
# Configuration
The configuration file for the sinks is a list of configurations. The `type` field in each specifies which sink to initialize.
```json
[
{
"type" : "stdout",
"meta_as_tags" : false
},
{
"type" : "http",
"host" : "localhost",
"port" : "4123",
"database" : "ccmetric",
"password" : "<jwt token>"
}
]
```
This example initializes two sinks, the `stdout` sink printing all metrics to the STDOUT and the `http` sink with the given `host`, `port`, `database` and `password`.
If `meta_as_tags` is set, all meta information attached to CCMetric are printed out as tags.
## Type `stdout`
```json
{
"type" : "stdout",
"meta_as_tags" : <true|false>
}
```
The `stdout` sink dumps all metrics to the STDOUT.
## Type `http`
```json
{
"type" : "http",
"host" : "<hostname>",
"port" : "<portnumber>",
"database" : "<database name>",
"password" : "<jwt token>",
"meta_as_tags" : <true|false>
}
```
The sink uses POST requests to send metrics to `http://<host>:<port>/<database>` using the JWT token as a JWT in the 'Authorization' header.
## Type `nats`
```json
{
"type" : "nats",
"host" : "<hostname>",
"port" : "<portnumber>",
"user" : "<username>",
"password" : "<password>",
"database" : "<database name>"
"meta_as_tags" : <true|false>
}
```
This sink publishes the CCMetric in a NATS environment using `host`, `port`, `user` and `password` for connecting. The metrics are published using the topic `database`.
## Type `influxdb`
```json
{
"type" : "influxdb",
"host" : "<hostname>",
"port" : "<portnumber>",
"user" : "<username>",
"password" : "<password or API key>",
"database" : "<database name>"
"organization": "<InfluxDB v2 organization>",
"ssl" : <true|false>,
"meta_as_tags" : <true|false>
}
```
This sink submits the CCMetrics to an InfluxDB time-series database. It uses `host`, `port` and `ssl` for connecting. For authentification, it uses either `user:password` if `user` is set and only `password` as API key. The `organization` and `database` are used for writing to the correct database.
# Contributing own sinks
A sink contains three functions and is derived from the type `Sink`:
* `Init(config SinkConfig) error`
* `Write(point CCMetric) error`
* `Flush() error`
* `Close()`
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.