Hazelcast Go Client

Hazelcast is a feature-rich and developer-friendly in-memory caching solution for your Go applications.

  • Access Hazelcast data structures plus distributed queues, topics, and more with the Hazelcast Go Client.
  • Declarative configuration support via JSON.
  • SQL support.
  • High-performance aggregation functions, such as sum, average, max, and min, for Hazelcast Map entries. They can run in parallel for each partition and are highly optimized for speed and low-memory consumption.

Quick Start + Download

Quick Start

Get Hazelcast.

Use the following command to install the Hazelcast Go client:

go get github.com/hazelcast/hazelcast-go-client

Next steps:

 

Downloads

Version Downloads Documentation
Hazelcast Go Client 1.4.2 (latest)
08/07/2024
Hazelcast Go Client 1.4.1
08/22/2023
Hazelcast Go Client 1.4.0
03/17/2023
Hazelcast Go Client 1.3.2
02/10/2023

For all downloads please see the Download Archives

Previous Releases

Code Samples

package main

import (
    "context"
    "fmt"

    "github.com/hazelcast/hazelcast-go-client"
)

func main() {
    ctx := context.TODO()
    // Start the client with defaults.
    client, err := hazelcast.StartNewClient(ctx)
    if err != nil {
        panic(err)
    }
    // Get a reference to the map.
    myMap, err := client.GetMap(ctx, "my-map")
    if err != nil {
        panic(err)
    }
    // Set a value in the map.
    err = myMap.Set(ctx, "some-key", "some-value")
    if err != nil {
        panic(err)
    }
    // Get the value back and print it.
    value, err := myMap.Get(ctx, "some-key")
    if err != nil {
        panic(err)
    }
    fmt.Println("Got the value back:", value)
}
 
package main

import (
    "context"
    "fmt"

    "github.com/hazelcast/hazelcast-go-client"
)

func main() {
    ctx := context.TODO()
    // Start the client with defaults.
    client, err := hazelcast.StartNewClient(ctx)
    if err != nil {
        panic(err)
    }
    // Get a reference to the replicated map.
    myMap, err := client.GetReplicatedMap(ctx, "my-replicated-map")
    if err != nil {
        panic(err)
    }
    // Put a value in the map and retrieve the previous value.
    oldValue, err := myMap.Put(ctx, "some-key", "some-value")
    if err != nil {
        panic(err)
    }
    fmt.Println("Previous value:", oldValue)
    // Get the value back and print it.
    value, err := myMap.Get(ctx, "some-key")
    if err != nil {
        panic(err)
    }
    fmt.Println("Got the value back:", value)
}
 
package main

import (
    "context"
    "fmt"

    "github.com/hazelcast/hazelcast-go-client"
)

func main() {
    ctx := context.TODO()
    // Start the client with defaults.
    client, err := hazelcast.StartNewClient(ctx)
    if err != nil {
        panic(err)
    }
    // Get a reference to the multi map.
    myMap, err := client.GetMultiMap(ctx, "my-multi-map")
    if err != nil {
        panic(err)
    }
    // Put values in the map with the same key.
    err = myMap.PutAll(ctx, "some-key", "some-value-1", "some-value-2", "some-value-3")
    if err != nil {
        panic(err)
    }
    // Get the values back and print it.
    values, err := myMap.Get(ctx, "some-key")
    if err != nil {
        panic(err)
    }
    fmt.Println("Got the values back:", values)
}
 
package main

import (
    "context"
    "fmt"

    "github.com/hazelcast/hazelcast-go-client"
)

func main() {
    ctx := context.TODO()
    // Start the client with defaults.
    client, err := hazelcast.StartNewClient(ctx)
    if err != nil {
        panic(err)
    }
    // Get a reference to the set.
    mySet, err := client.GetSet(ctx, "my-set")
    if err != nil {
        panic(err)
    }
    // Add items to set.
    // Note that value1 is added twice.
    changed, err := mySet.AddAll(ctx, "value1", "value2", "value1", "value3")
    if err != nil {
        panic(err)
    }
    fmt.Println("Was the set changed?", changed)
    // Print contents of the set
    items, err := mySet.GetAll(ctx)
    if err != nil {
        panic(err)
    }
    // Get the items back and print them.
    fmt.Println("Got the items back:", items)
}
 
package main

import (
    "context"
    "fmt"

    "github.com/hazelcast/hazelcast-go-client"
)

func main() {
    ctx := context.TODO()
    // Start the client with defaults.
    client, err := hazelcast.StartNewClient(ctx)
    if err != nil {
        panic(err)
    }
    // Get a reference to the list.
    myList, err := client.GetList(ctx, "my-list")
    if err != nil {
        panic(err)
    }
    _, err = myList.AddAll(ctx, "tic", "toc")
    if err != nil {
        panic(err)
    }
    // Get and print list items.
    items, err := myList.GetAll(ctx)
    if err != nil {
        panic(err)
    }
    fmt.Println("List items:", items)
}
 
package main

import (
    "context"
    "fmt"

    "github.com/hazelcast/hazelcast-go-client"
)

func main() {
    ctx := context.TODO()
    // Start the client with defaults.
    client, err := hazelcast.StartNewClient(ctx)
    if err != nil {
        panic(err)
    }
    // Get a reference to the queue.
    myQueue, err := client.GetQueue(ctx, "my-queue")
    if err != nil {
        panic(err)
    }
    // Add an item to the queue if space is available (non-blocking).
    added, err := myQueue.Add(ctx, "item 1")
    if err != nil {
        panic(err)
    }
    fmt.Println("Added?", added)
    // Get the head of the queue if available and print item.
    item, err := myQueue.Poll(ctx)
    if err != nil {
        panic(err)
    }
    fmt.Println("Got item:", item)
}
 
package main

import (
    "context"
    "fmt"

    "github.com/hazelcast/hazelcast-go-client"
)

// messageListener handles incoming messages to the topic.
func messageListener(event *hazelcast.MessagePublished) {
    fmt.Println("Received message: ", event.Value)
}

func main() {
    ctx := context.TODO()
    // Start the client with defaults.
    client, err := hazelcast.StartNewClient(ctx)
    if err != nil {
        panic(err)
    }
    // Get a reference to the queue.
    myTopic, err := client.GetTopic(ctx, "my-topic")
    if err != nil {
        panic(err)
    }
    // Add a message listener to the topic.
    _, err = myTopic.AddMessageListener(ctx, messageListener)
    if err != nil {
        panic(err)
    }
    // Publish messages to topic
    for i := 0; i < 10; i++ {
        err = myTopic.Publish(ctx, fmt.Sprintf("Message %d", i))
        if err != nil {
            panic(err)
        }
    }
    // Shutdown the client.
    client.Shutdown(ctx)
}
 
package main

import (
    "context"
    "fmt"

    "github.com/hazelcast/hazelcast-go-client"
    "github.com/hazelcast/hazelcast-go-client/predicate"
    "github.com/hazelcast/hazelcast-go-client/serialization"
)

func main() {
    ctx := context.TODO()
    // Start the client with defaults.
    client, err := hazelcast.StartNewClient(ctx)
    if err != nil {
        panic(err)
    }
    // Get a reference to the map.
    myMap, err := client.GetMap(ctx, "my-map")
    if err != nil {
        panic(err)
    }
    // Populate the map, error handling is omitted here for brevity
    _ = myMap.Set(ctx, "key-1", serialization.JSON(`{"property: 5}`))
    _ = myMap.Set(ctx, "key-2", serialization.JSON(`{"property": 10}`))
    _ = myMap.Set(ctx, "key-3", serialization.JSON(`{"property": 15}`))
    // Filter the entries in the map based on a predicate and print those.
    pred := predicate.And(predicate.Greater("property", 8), predicate.Less("property", 12))
    entries, err := myMap.GetEntrySetWithPredicate(ctx, pred)
    if err != nil {
        panic(err)
    }
    fmt.Println(entries)
}