Introduction

Grey includes support for a number of different synthetic probing target types, which should allow you to cover many of the most common service types.

Tips

For a quick introduction to using Grey to probe a service, take a look at the Usage Guide.

When defining a probe, you can specify the target type using the !Http, !Grpc, !Tcp, !Dns, or !Script syntax. These target types each accept a distinct set of configuration options which are documented on their respective pages.

Example

probes:
  - name: http.example
    policy:
      interval: 5s
      timeout: 2s
      retries: 3
    target: !Http
      url: https://example.com
    validators:
      http.status: !OneOf [200]
      http.header.content-type: !Contains "text/html"

  - name: grpc.example
    policy:
      interval: 5s
      timeout: 2s
      retries: 3
    target: !Grpc
      url: https://api.example.com:443
      service: "myservice.v1.MyService"
    validators:
      grpc.status: !Equals "SERVING"
      grpc.status_code: !Equals 1

  - name: tcp.example
    policy:
      interval: 5s
      timeout: 2s
      retries: 3
    target: !Tcp
      host: example.com:6379
    validators:
      net.ip: !Equals "127.0.0.1"

  - name: dns.example
    policy:
      interval: 5s
      timeout: 2s
      retries: 3
    target: !Dns
      domain: example.com
      record_type: MX
    validators:
      dns.answers: !Contains "10 smtp.example.com"

  - name: script.example
    policy:
      interval: 3s0
      timeout: 5s
      retries: 3
    target: !Script
      code: |
        const response = await fetch("https://api.example.com/health");
        output["api.status"] = response.status;
        output["api.ok"] = response.ok;
        
        const data = await response.json();
        output["api.version"] = data.version;
    validators:
      api.status: !Equals 200
      api.ok: !Equals true
      api.version: !Contains "v1"