github.com/apache/beam/sdks/v2@v2.48.2/go/test/integration/internal/ports/ports.go (about)

     1  // Licensed to the Apache Software Foundation (ASF) under one or more
     2  // contributor license agreements.  See the NOTICE file distributed with
     3  // this work for additional information regarding copyright ownership.
     4  // The ASF licenses this file to You under the Apache License, Version 2.0
     5  // (the "License"); you may not use this file except in compliance with
     6  // the License.  You may obtain a copy of the License at
     7  //
     8  //    http://www.apache.org/licenses/LICENSE-2.0
     9  //
    10  // Unless required by applicable law or agreed to in writing, software
    11  // distributed under the License is distributed on an "AS IS" BASIS,
    12  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  // See the License for the specific language governing permissions and
    14  // limitations under the License.
    15  
    16  // Package ports contains utilities for handling ports needed for integration
    17  // tests.
    18  package ports
    19  
    20  import "net"
    21  
    22  // GetOpenTCP gets an open TCP port and returns it, or an error on failure.
    23  func GetOpenTCP() (int, error) {
    24  	listener, err := net.Listen("tcp", ":0")
    25  	if err != nil {
    26  		return 0, err
    27  	}
    28  	defer listener.Close()
    29  	return listener.Addr().(*net.TCPAddr).Port, nil
    30  }