github.com/apache/beam/sdks/v2@v2.48.2/go/examples/xlang/multi_input_output/multi.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  // multi exemplifies using a cross-language transform with multiple inputs and
    17  // outputs from a test expansion service.
    18  //
    19  // Prerequisites to run wordcount:
    20  // –> [Required] Job needs to be submitted to a portable runner (--runner=universal)
    21  // –> [Required] Endpoint of job service needs to be passed (--endpoint=<ip:port>)
    22  // –> [Required] Endpoint of expansion service needs to be passed (--expansion_addr=<ip:port>)
    23  // –> [Optional] Environment type can be LOOPBACK. Defaults to DOCKER. (--environment_type=LOOPBACK|DOCKER)
    24  package main
    25  
    26  import (
    27  	"context"
    28  	"flag"
    29  	"log"
    30  
    31  	"github.com/apache/beam/sdks/v2/go/examples/xlang"
    32  	"github.com/apache/beam/sdks/v2/go/pkg/beam"
    33  	"github.com/apache/beam/sdks/v2/go/pkg/beam/testing/passert"
    34  	"github.com/apache/beam/sdks/v2/go/pkg/beam/x/beamx"
    35  
    36  	// Imports to enable correct filesystem access and runner setup in LOOPBACK mode
    37  	_ "github.com/apache/beam/sdks/v2/go/pkg/beam/io/filesystem/gcs"
    38  	_ "github.com/apache/beam/sdks/v2/go/pkg/beam/io/filesystem/local"
    39  	_ "github.com/apache/beam/sdks/v2/go/pkg/beam/runners/universal"
    40  )
    41  
    42  var (
    43  	expansionAddr = flag.String("expansion_addr", "", "Address of Expansion Service")
    44  )
    45  
    46  func main() {
    47  	flag.Parse()
    48  	beam.Init()
    49  
    50  	if *expansionAddr == "" {
    51  		log.Fatal("No expansion address provided")
    52  	}
    53  
    54  	p := beam.NewPipeline()
    55  	s := p.Root()
    56  
    57  	main1 := beam.CreateList(s, []string{"a", "bb"})
    58  	main2 := beam.CreateList(s, []string{"x", "yy", "zzz"})
    59  	side := beam.CreateList(s, []string{"s"})
    60  
    61  	// Using the cross-language transform
    62  	mainOut, sideOut := xlang.Multi(s, *expansionAddr, main1, main2, side)
    63  
    64  	passert.Equals(s, mainOut, "as", "bbs", "xs", "yys", "zzzs")
    65  	passert.Equals(s, sideOut, "ss")
    66  
    67  	if err := beamx.Run(context.Background(), p); err != nil {
    68  		log.Fatalf("Failed to execute job: %v", err)
    69  	}
    70  }