fix: accept numeric broker machine ids

internal/cli/coordinator.go

@@ -37,7 +37,7 @@ type CoordinatorLease struct {
 }
 
 type CoordinatorMachine struct {
-	ID         string            `json:"id"`
+	ID         CoordinatorID     `json:"id"`
 	Provider   string            `json:"provider"`
 	CloudID    string            `json:"cloudID"`
 	Name       string            `json:"name"`
@@ -47,6 +47,22 @@ type CoordinatorMachine struct {
 	Labels     map[string]string `json:"labels"`
 }
 
+type CoordinatorID string
+
+func (id *CoordinatorID) UnmarshalJSON(data []byte) error {
+	var s string
+	if err := json.Unmarshal(data, &s); err == nil {
+		*id = CoordinatorID(s)
+		return nil
+	}
+	var n int64
+	if err := json.Unmarshal(data, &n); err == nil {
+		*id = CoordinatorID(fmt.Sprint(n))
+		return nil
+	}
+	return fmt.Errorf("invalid coordinator id: %s", string(data))
+}
+
 func newCoordinatorClient(cfg Config) (*CoordinatorClient, bool, error) {
 	if cfg.Coordinator == "" {
 		return nil, false, nil

internal/cli/coordinator_test.go

@@ -0,0 +1,23 @@
+package cli
+
+import (
+	"encoding/json"
+	"testing"
+)
+
+func TestCoordinatorMachineIDAcceptsStringOrNumber(t *testing.T) {
+	for name, input := range map[string]string{
+		"string": `{"id":"i-123","labels":{}}`,
+		"number": `{"id":128694755,"labels":{}}`,
+	} {
+		t.Run(name, func(t *testing.T) {
+			var machine CoordinatorMachine
+			if err := json.Unmarshal([]byte(input), &machine); err != nil {
+				t.Fatal(err)
+			}
+			if machine.ID == "" {
+				t.Fatalf("machine ID was empty")
+			}
+		})
+	}
+}