easeq/go-consul-registry

A Consul Resolver for the GRPC-Go Library

Consul Resolver for the grpc-go library

The repository provides a consul resolver for the GRPC-Go Library >= 1.26.

To register the resolver with the GRPC-Go library run:

resolver.Register(consul.NewBuilder())

Afterwards it can be used by calling grpc.Dial() and passing an URI in the following format:

consul://[<consul-server>]/<serviceName>[?<OPT>[&<OPT>]...]

The default for <consul-server> is 127.0.0.1:8500.

<OPT> is one of:

OPT	Format	Default	Description
scheme	http|https	http	Establish connection to consul via http or https.
tags	<tag>,[,<tag>]...		Filter service by tags
health	healthy|fallbackToUnhealthy	healthy	healthy resolves only to services with a passing health status. fallbackToUnhealthy resolves to unhealthy ones if none exist with passing healthy status.

Example resolver

package main

import (
  "google.golang.org/grpc"
  "google.golang.org/grpc/resolver"

  _ "github.com/easeq/go-consul-registry/v2/consul"
)

func main() {
  // Create a GRPC-Client connection with the default load-balancer.
  // The addresses of the service "user-service" with the tags
  // "primary" and "eu" are resolved via the consul server "10.10.0.1:1234".
  // If no services with a passing health-checks are available, the connection
  // is established to unhealthy ones.
  client, _ := grpc.Dial("consul://10.10.0.1:1234/user-service?scheme=https&tags=primary,eu&health=fallbackToUnhealthy")

  // Instantiates a GRPC client with a round-robin load-balancer.
  // The addresses of the service "metrics" are resolved via the default
  // consul server "http://127.0.01:8500".
  client, _ = grpc.Dial("consul://metrics", grpc.WithBalancerName("round_robin"))
}

Example registration

package main

import (
  "context"
  "google.golang.org/grpc"
  "github.com/easeq/go-consul-registry/v2/consul"
)

func main() {
  ctx := context.Background()

  // Register a service with consul having the following details:
  // Service name: user-service
  // GRPC server at: localhost:9090
  // Consul server at: 127.0.0.1:8500
  // TTL: 15
  consul.Register(ctx, "user-service", "localhost", 9090, "127.0.0.1:8500", 15)
}