mirror of
https://github.com/mailgun/groupcache.git
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48a0ce2463
* `Get()` now returns immediately when context is done during a groupcache peer conversation. Previously `Get()` would call the `Getter` with a done context.
88 lines
2.0 KiB
Go
88 lines
2.0 KiB
Go
package groupcache_test
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import (
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"context"
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"fmt"
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"log"
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"time"
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"github.com/mailgun/groupcache/v2"
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)
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func ExampleUsage() {
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/*
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// Keep track of peers in our cluster and add our instance to the pool `http://localhost:8080`
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pool := groupcache.NewHTTPPoolOpts("http://localhost:8080", &groupcache.HTTPPoolOptions{})
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// Add more peers to the cluster
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//pool.Set("http://peer1:8080", "http://peer2:8080")
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server := http.Server{
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Addr: "localhost:8080",
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Handler: pool,
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}
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// Start a HTTP server to listen for peer requests from the groupcache
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go func() {
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log.Printf("Serving....\n")
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if err := server.ListenAndServe(); err != nil {
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log.Fatal(err)
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}
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}()
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defer server.Shutdown(context.Background())
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*/
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// Create a new group cache with a max cache size of 3MB
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group := groupcache.NewGroup("users", 3000000, groupcache.GetterFunc(
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func(ctx context.Context, id string, dest groupcache.Sink) error {
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// In a real scenario we might fetch the value from a database.
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/*if user, err := fetchUserFromMongo(ctx, id); err != nil {
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return err
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}*/
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user := User{
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Id: "12345",
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Name: "John Doe",
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Age: 40,
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IsSuper: true,
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}
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// Set the user in the groupcache to expire after 5 minutes
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if err := dest.SetProto(&user, time.Now().Add(time.Minute*5)); err != nil {
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return err
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}
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return nil
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},
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))
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var user User
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ctx, cancel := context.WithTimeout(context.Background(), time.Second)
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defer cancel()
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if err := group.Get(ctx, "12345", groupcache.ProtoSink(&user)); err != nil {
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log.Fatal(err)
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}
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fmt.Printf("-- User --\n")
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fmt.Printf("Id: %s\n", user.Id)
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fmt.Printf("Name: %s\n", user.Name)
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fmt.Printf("Age: %d\n", user.Age)
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fmt.Printf("IsSuper: %t\n", user.IsSuper)
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/*
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// Remove the key from the groupcache
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if err := group.Remove(ctx, "12345"); err != nil {
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fmt.Printf("Remove Err: %s\n", err)
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log.Fatal(err)
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}
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*/
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// Output: -- User --
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// Id: 12345
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// Name: John Doe
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// Age: 40
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// IsSuper: true
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}
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