PrometheusFileServiceDiscoveryApi

An HTTP service for updating a .json file when using Prometheus with file_sd_config.

Configuration

Add file service discovery to prometheus. If your targets.json file is next to the prometheus.exe, you can add this to the prometheus.yml file.

 - job_name: 'targets-json'
    file_sd_configs:
    - files:
      - targets.json

Add a file appsettings.json next to the executable prom-target-api.exe (not provided) file.

{
    "Host": "http://localhost:6000",
    "TargetFileLocations": [
        {
            "Name": "Production",
            "TargetsFileLocation": "C:\\Workfolder\\prometheus-2.1.0.windows-amd64\\production_targets.json"
        },
        {
            "Name": "Test",
            "TargetsFileLocation": "C:\\Workfolder\\prometheus-2.1.0.windows-amd64\\test_targets.json"
        }
    ]
}

Concept

This is a service that acts as a RESTful API that works with resources called 'targets'. These are just a copy of the targets as described in the file_sd_config configuration. Be sure to honor the conventions of host, labelname and labelvalue. The service does not validate that your models comply with the Prometheus requirements.

//this is what a `target resource` 
{
    //this is the actual endpoint that will be scraped
    "targets": [
        "mynewtarget.com", //this is a target
	"someothertarget.com" //this is a target
    ],
    "labels": {
        "web": "WEBSERVER-01",      
        "mylabel": "myvalue"      
    }
}

• To make life easier (?) the identification of a target resource works with any of the target names in the targets collection.
• You can update a target inside the targets collection, but the new targets collection must always contain the name of the target you used to identifiy the target resource with.
• A target must be unique within the entire collection of target resources

Endpoints

GET

http://localhost:6000/api/v1/targets/production

http://localhost:6000/api/v1/targets/production/mytarget.com

PUT

http://localhost:6000/api/v1/targets/production

{
    "targets": [
        "mynewtarget.com"
    ],
    "labels": {
        "web": "WEBSERVER-01",      
        "mylabel": "myvalue"      
    }
}

PATCH

http://localhost:6000/api/v1/targets/production/mynewtarget.com

{
    "targets": [
        "mynewtarget.com"
    ],
    "labels": {
         "web": "WEBSERVER-02",       
         "mylabel": "mynewvalue"       
    }
}

DELETE

http://localhost:6000/api/v1/targets/production/mytarget.com