Tim Gross e5f5fc9301
api: add CheckRegisterOpts method to Agent API (#18943)
Ongoing work to support Nomad Workload Identity for authenticating with Consul
will mean that Nomad's service registration sync with Consul will want to use
Consul tokens scoped to individual workloads for registering services and
checks. The `CheckRegister` method in the API doesn't have an option to pass the
token in, which prevent us from sharing the same Consul connection for all
workloads. Add a `CheckRegisterOpts` to match the behavior of
`ServiceRegisterOpts`.
2023-09-25 08:25:02 -07:00
..
2023-04-19 14:45:00 -05:00
2023-09-05 13:34:44 -07:00
2023-08-11 09:12:13 -04:00

Consul API Client

This package provides the api package which provides programmatic access to the full Consul API.

The full documentation is available on Godoc.

Usage

Below is an example of using the Consul client. To run the example, you must first install Consul and Go.

To run the client API, create a new Go module.

go mod init consul-demo

Copy the example code into a file called main.go in the directory where the module is defined. As seen in the example, the Consul API is often imported with the alias capi.

package main

import (
	"fmt"

	capi "github.com/hashicorp/consul/api"
)

func main() {
	// Get a new client
	client, err := capi.NewClient(capi.DefaultConfig())
	if err != nil {
		panic(err)
	}

	// Get a handle to the KV API
	kv := client.KV()

	// PUT a new KV pair
	p := &capi.KVPair{Key: "REDIS_MAXCLIENTS", Value: []byte("1000")}
	_, err = kv.Put(p, nil)
	if err != nil {
		panic(err)
	}

	// Lookup the pair
	pair, _, err := kv.Get("REDIS_MAXCLIENTS", nil)
	if err != nil {
		panic(err)
	}
	fmt.Printf("KV: %v %s\n", pair.Key, pair.Value)
}

Install the Consul API dependency with go mod tidy.

In a separate terminal window, start a local Consul server.

consul agent -dev -node machine

Run the example.

go run .

You should get the following result printed to the terminal.

KV: REDIS_MAXCLIENTS 1000

After running the code, you can also view the values in the Consul UI on your local machine at http://localhost:8500/ui/dc1/kv