Etcd Watcher

Etcd Watcher is the Etcd watcher for Casbin. With this library, Casbin can synchronize the policy with the database in multiple enforcer instances.

Installation

go get github.com/casbin/etcd-watcher/v2

Simple Example

package main

import (
    "log"

    casbin "github.com/casbin/casbin/v2"
    etcdwatcher "github.com/casbin/etcd-watcher/v2"
)

func updateCallback(rev string) {
    log.Println("New revision detected:", rev)
}

func main() {
    // Initialize the watcher.
    // Use the endpoint of etcd cluster as parameter.
    w, _ := etcdwatcher.NewWatcher([]string{"http://127.0.0.1:2379"}, "keyname")

    // Initialize the enforcer.
    e, _ := casbin.NewEnforcer("examples/rbac_model.conf", "examples/rbac_policy.csv")

    // Set the watcher for the enforcer.
    e.SetWatcher(w)

    // By default, the watcher's callback is automatically set to the
    // enforcer's LoadPolicy() in the SetWatcher() call.
    // We can change it by explicitly setting a callback.
    w.SetUpdateCallback(updateCallback)

    // Update the policy to test the effect.
    // You should see "[New revision detected: X]" in the log.
    e.SavePolicy()
}

Simple Example（Configuration Mode）

package main

import (
    "log"

    casbin "github.com/casbin/casbin/v2"
    etcdwatcher "github.com/casbin/etcd-watcher/v2"
)

func updateCallback(rev string) {
    log.Println("New revision detected:", rev)
}

func main() {
    // Initialize the watcher.
    // Use the configuration file as the parameter
    w, _ := etcdwatcher.NewWatcherWithConfig(etcdwatcher.WatcherConfig{
        Hosts: []string{"http://127.0.0.1:2379"},
        Key:   "/casbin",
        User:  "root",
        Pass:  "123",
    })

    // Initialize the enforcer.
    e, _ := casbin.NewEnforcer("examples/rbac_model.conf", "examples/rbac_policy.csv")

    // Set the watcher for the enforcer.
    e.SetWatcher(w)

    // By default, the watcher's callback is automatically set to the
    // enforcer's LoadPolicy() in the SetWatcher() call.
    // We can change it by explicitly setting a callback.
    w.SetUpdateCallback(updateCallback)

    // Update the policy to test the effect.
    // You should see "[New revision detected: X]" in the log.
    e.SavePolicy()
}

Getting Help

• Casbin

License

This project is under Apache 2.0 License. See the LICENSE file for the full license text.