Merge pull request #1 from kitex-contrib/add_demo

feat: add demo

README.md

@@ -11,7 +11,7 @@ This resolver needs an implemented Resolver, which is able to resolve instances
 ```
 // Define a filter function.
 // For example, only get the instances with a tag of {"k":"v"}.
-filterFunc = func(ctx context.Context, instance []discovery.Instance) []discovery.Instance {
+filterFunc := func(ctx context.Context, instance []discovery.Instance) []discovery.Instance {
      var res []discovery.Instance
      for _, ins := range instance {
          if v, ok := ins.Tag("k"); ok && v == "v" {
@@ -42,3 +42,6 @@ tagResolver := ruleBasedResolver.NewRuleBasedResolver(resolver, filterRule)
 // add this option when construct Kitex Client
 opt := client.WithResolver(tagResolver) 
 ```
+
+## Demo
+Please refer to the `/demo` for details.

demo/README.md

@@ -0,0 +1,4 @@
+# Demo
+This demo uses [etcd-registry](github.com/kitex-contrib/registry-etcd) as the original resolver and configure a filter rule to use the rule-based resolver.
+
+Please make sure [etcd](https://etcd.io/) is configured before running the demo. 

demo/go.mod

@@ -0,0 +1,31 @@
+module demo
+
+go 1.18
+
+require (
+	github.com/cloudwego/kitex v0.5.0
+	github.com/kitex-contrib/registry-etcd v0.1.0
+	github.com/kitex-contrib/resolver-rule-based v0.0.0-20230309083100-6cf7b6e5f2b4
+)
+
+require (
+	github.com/apache/thrift v0.13.0 // indirect
+	github.com/choleraehyq/pid v0.0.16 // indirect
+	github.com/coreos/go-semver v0.3.0 // indirect
+	github.com/coreos/go-systemd/v22 v22.3.2 // indirect
+	github.com/gogo/protobuf v1.3.2 // indirect
+	github.com/golang/protobuf v1.5.2 // indirect
+	go.etcd.io/etcd/api/v3 v3.5.5 // indirect
+	go.etcd.io/etcd/client/pkg/v3 v3.5.5 // indirect
+	go.etcd.io/etcd/client/v3 v3.5.5 // indirect
+	go.uber.org/atomic v1.8.0 // indirect
+	go.uber.org/multierr v1.6.0 // indirect
+	go.uber.org/zap v1.17.0 // indirect
+	golang.org/x/net v0.0.0-20220722155237-a158d28d115b // indirect
+	golang.org/x/sys v0.0.0-20220817070843-5a390386f1f2 // indirect
+	golang.org/x/text v0.6.0 // indirect
+	google.golang.org/genproto v0.0.0-20210602131652-f16073e35f0c // indirect
+	google.golang.org/grpc v1.41.0 // indirect
+	google.golang.org/protobuf v1.28.1 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)