| // Copyright 2016 The etcd Authors |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package clientv3_test |
| |
| import ( |
| "context" |
| "fmt" |
| "log" |
| |
| "github.com/coreos/etcd/clientv3" |
| "github.com/coreos/etcd/etcdserver/api/v3rpc/rpctypes" |
| ) |
| |
| func ExampleKV_put() { |
| cli, err := clientv3.New(clientv3.Config{ |
| Endpoints: endpoints, |
| DialTimeout: dialTimeout, |
| }) |
| if err != nil { |
| log.Fatal(err) |
| } |
| defer cli.Close() |
| |
| ctx, cancel := context.WithTimeout(context.Background(), requestTimeout) |
| _, err = cli.Put(ctx, "sample_key", "sample_value") |
| cancel() |
| if err != nil { |
| log.Fatal(err) |
| } |
| } |
| |
| func ExampleKV_putErrorHandling() { |
| cli, err := clientv3.New(clientv3.Config{ |
| Endpoints: endpoints, |
| DialTimeout: dialTimeout, |
| }) |
| if err != nil { |
| log.Fatal(err) |
| } |
| defer cli.Close() |
| |
| ctx, cancel := context.WithTimeout(context.Background(), requestTimeout) |
| _, err = cli.Put(ctx, "", "sample_value") |
| cancel() |
| if err != nil { |
| switch err { |
| case context.Canceled: |
| fmt.Printf("ctx is canceled by another routine: %v\n", err) |
| case context.DeadlineExceeded: |
| fmt.Printf("ctx is attached with a deadline is exceeded: %v\n", err) |
| case rpctypes.ErrEmptyKey: |
| fmt.Printf("client-side error: %v\n", err) |
| default: |
| fmt.Printf("bad cluster endpoints, which are not etcd servers: %v\n", err) |
| } |
| } |
| // Output: client-side error: etcdserver: key is not provided |
| } |
| |
| func ExampleKV_get() { |
| cli, err := clientv3.New(clientv3.Config{ |
| Endpoints: endpoints, |
| DialTimeout: dialTimeout, |
| }) |
| if err != nil { |
| log.Fatal(err) |
| } |
| defer cli.Close() |
| |
| _, err = cli.Put(context.TODO(), "foo", "bar") |
| if err != nil { |
| log.Fatal(err) |
| } |
| |
| ctx, cancel := context.WithTimeout(context.Background(), requestTimeout) |
| resp, err := cli.Get(ctx, "foo") |
| cancel() |
| if err != nil { |
| log.Fatal(err) |
| } |
| for _, ev := range resp.Kvs { |
| fmt.Printf("%s : %s\n", ev.Key, ev.Value) |
| } |
| // Output: foo : bar |
| } |
| |
| func ExampleKV_getWithRev() { |
| cli, err := clientv3.New(clientv3.Config{ |
| Endpoints: endpoints, |
| DialTimeout: dialTimeout, |
| }) |
| if err != nil { |
| log.Fatal(err) |
| } |
| defer cli.Close() |
| |
| presp, err := cli.Put(context.TODO(), "foo", "bar1") |
| if err != nil { |
| log.Fatal(err) |
| } |
| _, err = cli.Put(context.TODO(), "foo", "bar2") |
| if err != nil { |
| log.Fatal(err) |
| } |
| |
| ctx, cancel := context.WithTimeout(context.Background(), requestTimeout) |
| resp, err := cli.Get(ctx, "foo", clientv3.WithRev(presp.Header.Revision)) |
| cancel() |
| if err != nil { |
| log.Fatal(err) |
| } |
| for _, ev := range resp.Kvs { |
| fmt.Printf("%s : %s\n", ev.Key, ev.Value) |
| } |
| // Output: foo : bar1 |
| } |
| |
| func ExampleKV_getSortedPrefix() { |
| cli, err := clientv3.New(clientv3.Config{ |
| Endpoints: endpoints, |
| DialTimeout: dialTimeout, |
| }) |
| if err != nil { |
| log.Fatal(err) |
| } |
| defer cli.Close() |
| |
| for i := range make([]int, 3) { |
| ctx, cancel := context.WithTimeout(context.Background(), requestTimeout) |
| _, err = cli.Put(ctx, fmt.Sprintf("key_%d", i), "value") |
| cancel() |
| if err != nil { |
| log.Fatal(err) |
| } |
| } |
| |
| ctx, cancel := context.WithTimeout(context.Background(), requestTimeout) |
| resp, err := cli.Get(ctx, "key", clientv3.WithPrefix(), clientv3.WithSort(clientv3.SortByKey, clientv3.SortDescend)) |
| cancel() |
| if err != nil { |
| log.Fatal(err) |
| } |
| for _, ev := range resp.Kvs { |
| fmt.Printf("%s : %s\n", ev.Key, ev.Value) |
| } |
| // Output: |
| // key_2 : value |
| // key_1 : value |
| // key_0 : value |
| } |
| |
| func ExampleKV_delete() { |
| cli, err := clientv3.New(clientv3.Config{ |
| Endpoints: endpoints, |
| DialTimeout: dialTimeout, |
| }) |
| if err != nil { |
| log.Fatal(err) |
| } |
| defer cli.Close() |
| |
| ctx, cancel := context.WithTimeout(context.Background(), requestTimeout) |
| defer cancel() |
| |
| // count keys about to be deleted |
| gresp, err := cli.Get(ctx, "key", clientv3.WithPrefix()) |
| if err != nil { |
| log.Fatal(err) |
| } |
| |
| // delete the keys |
| dresp, err := cli.Delete(ctx, "key", clientv3.WithPrefix()) |
| if err != nil { |
| log.Fatal(err) |
| } |
| |
| fmt.Println("Deleted all keys:", int64(len(gresp.Kvs)) == dresp.Deleted) |
| // Output: |
| // Deleted all keys: true |
| } |
| |
| func ExampleKV_compact() { |
| cli, err := clientv3.New(clientv3.Config{ |
| Endpoints: endpoints, |
| DialTimeout: dialTimeout, |
| }) |
| if err != nil { |
| log.Fatal(err) |
| } |
| defer cli.Close() |
| |
| ctx, cancel := context.WithTimeout(context.Background(), requestTimeout) |
| resp, err := cli.Get(ctx, "foo") |
| cancel() |
| if err != nil { |
| log.Fatal(err) |
| } |
| compRev := resp.Header.Revision // specify compact revision of your choice |
| |
| ctx, cancel = context.WithTimeout(context.Background(), requestTimeout) |
| _, err = cli.Compact(ctx, compRev) |
| cancel() |
| if err != nil { |
| log.Fatal(err) |
| } |
| } |
| |
| func ExampleKV_txn() { |
| cli, err := clientv3.New(clientv3.Config{ |
| Endpoints: endpoints, |
| DialTimeout: dialTimeout, |
| }) |
| if err != nil { |
| log.Fatal(err) |
| } |
| defer cli.Close() |
| |
| kvc := clientv3.NewKV(cli) |
| |
| _, err = kvc.Put(context.TODO(), "key", "xyz") |
| if err != nil { |
| log.Fatal(err) |
| } |
| |
| ctx, cancel := context.WithTimeout(context.Background(), requestTimeout) |
| _, err = kvc.Txn(ctx). |
| // txn value comparisons are lexical |
| If(clientv3.Compare(clientv3.Value("key"), ">", "abc")). |
| // the "Then" runs, since "xyz" > "abc" |
| Then(clientv3.OpPut("key", "XYZ")). |
| // the "Else" does not run |
| Else(clientv3.OpPut("key", "ABC")). |
| Commit() |
| cancel() |
| if err != nil { |
| log.Fatal(err) |
| } |
| |
| gresp, err := kvc.Get(context.TODO(), "key") |
| cancel() |
| if err != nil { |
| log.Fatal(err) |
| } |
| for _, ev := range gresp.Kvs { |
| fmt.Printf("%s : %s\n", ev.Key, ev.Value) |
| } |
| // Output: key : XYZ |
| } |
| |
| func ExampleKV_do() { |
| cli, err := clientv3.New(clientv3.Config{ |
| Endpoints: endpoints, |
| DialTimeout: dialTimeout, |
| }) |
| if err != nil { |
| log.Fatal(err) |
| } |
| defer cli.Close() |
| |
| ops := []clientv3.Op{ |
| clientv3.OpPut("put-key", "123"), |
| clientv3.OpGet("put-key"), |
| clientv3.OpPut("put-key", "456")} |
| |
| for _, op := range ops { |
| if _, err := cli.Do(context.TODO(), op); err != nil { |
| log.Fatal(err) |
| } |
| } |
| } |