github.com/m3db/m3@v1.5.0/src/query/util/execution/parallel.go (about)

     1  // Copyright (c) 2018 Uber Technologies, Inc.
     2  //
     3  // Permission is hereby granted, free of charge, to any person obtaining a copy
     4  // of this software and associated documentation files (the "Software"), to deal
     5  // in the Software without restriction, including without limitation the rights
     6  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
     7  // copies of the Software, and to permit persons to whom the Software is
     8  // furnished to do so, subject to the following conditions:
     9  //
    10  // The above copyright notice and this permission notice shall be included in
    11  // all copies or substantial portions of the Software.
    12  //
    13  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    14  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    15  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    16  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    17  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    18  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
    19  // THE SOFTWARE.
    20  
    21  package execution
    22  
    23  import (
    24  	"context"
    25  
    26  	"golang.org/x/sync/errgroup"
    27  )
    28  
    29  // Request is input for parallel execution
    30  type Request interface {
    31  	Process(ctx context.Context) error
    32  }
    33  
    34  // RequestResponse is used to combine both request and response in output
    35  type RequestResponse struct {
    36  	Request  Request
    37  	Response *Response
    38  }
    39  
    40  // Response is returned from parallel execution
    41  type Response struct {
    42  	Value interface{}
    43  	Err   error
    44  }
    45  
    46  // ExecuteParallel executes a slice of requests in parallel
    47  func ExecuteParallel(ctx context.Context, requests []Request) error {
    48  	return processParallel(ctx, requests)
    49  }
    50  
    51  // Process the requests in parallel and stop on first error
    52  func processParallel(ctx context.Context, requests []Request) error {
    53  	g, ctx := errgroup.WithContext(ctx)
    54  	for _, req := range requests {
    55  		req := req
    56  		g.Go(func() error {
    57  			return req.Process(ctx)
    58  		})
    59  	}
    60  
    61  	return g.Wait()
    62  }