github.com/rbisecke/kafka-go@v0.4.27/findcoordinator_test.go (about)

     1  package kafka
     2  
     3  import (
     4  	"bufio"
     5  	"bytes"
     6  	"context"
     7  	"errors"
     8  	"fmt"
     9  	"reflect"
    10  	"strings"
    11  	"testing"
    12  	"time"
    13  )
    14  
    15  func TestFindCoordinatorResponseV0(t *testing.T) {
    16  	item := findCoordinatorResponseV0{
    17  		ErrorCode: 2,
    18  		Coordinator: findCoordinatorResponseCoordinatorV0{
    19  			NodeID: 3,
    20  			Host:   "b",
    21  			Port:   4,
    22  		},
    23  	}
    24  
    25  	b := bytes.NewBuffer(nil)
    26  	w := &writeBuffer{w: b}
    27  	item.writeTo(w)
    28  
    29  	var found findCoordinatorResponseV0
    30  	remain, err := (&found).readFrom(bufio.NewReader(b), b.Len())
    31  	if err != nil {
    32  		t.Error(err)
    33  		t.FailNow()
    34  	}
    35  	if remain != 0 {
    36  		t.Errorf("expected 0 remain, got %v", remain)
    37  		t.FailNow()
    38  	}
    39  	if !reflect.DeepEqual(item, found) {
    40  		t.Error("expected item and found to be the same")
    41  		t.FailNow()
    42  	}
    43  }
    44  
    45  func TestClientFindCoordinator(t *testing.T) {
    46  	client, shutdown := newLocalClient()
    47  	defer shutdown()
    48  
    49  	ctx, cancel := context.WithTimeout(context.Background(), 15*time.Second)
    50  	defer cancel()
    51  	resp, err := waitForCoordinatorIndefinitely(ctx, client, &FindCoordinatorRequest{
    52  		Addr:    client.Addr,
    53  		Key:     "TransactionalID-1",
    54  		KeyType: CoordinatorKeyTypeTransaction,
    55  	})
    56  
    57  	if err != nil {
    58  		t.Fatal(err)
    59  	}
    60  
    61  	if resp.Coordinator.Host != "localhost" {
    62  		t.Fatal("Coordinator should be found @ localhost")
    63  	}
    64  }
    65  
    66  // WaitForCoordinatorIndefinitely is a blocking call till a coordinator is found
    67  func waitForCoordinatorIndefinitely(ctx context.Context, c *Client, req *FindCoordinatorRequest) (*FindCoordinatorResponse, error) {
    68  	fmt.Println("Trying to find Coordinator.")
    69  	resp, err := c.FindCoordinator(ctx, req)
    70  
    71  	for shouldRetryfindingCoordinator(resp, err) && ctx.Err() == nil {
    72  		time.Sleep(1 * time.Second)
    73  		resp, err = c.FindCoordinator(ctx, req)
    74  	}
    75  	return resp, err
    76  }
    77  
    78  // Should retry looking for coordinator
    79  // Returns true when the test Kafka broker is still setting up
    80  func shouldRetryfindingCoordinator(resp *FindCoordinatorResponse, err error) bool {
    81  	brokerSetupIncomplete := err != nil &&
    82  		strings.Contains(
    83  			strings.ToLower(err.Error()),
    84  			strings.ToLower("unexpected EOF"))
    85  	coordinatorNotFound := resp != nil &&
    86  		resp.Error != nil &&
    87  		errors.Is(resp.Error, GroupCoordinatorNotAvailable)
    88  	return brokerSetupIncomplete || coordinatorNotFound
    89  }