go.uber.org/yarpc@v1.72.1/internal/errorsync/err.go (about)

     1  // Copyright (c) 2022 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 errorsync
    22  
    23  import "sync"
    24  
    25  // ErrorWaiter is similar to a WaitGroup except it allows collecting failures
    26  // from subtasks.
    27  type ErrorWaiter struct {
    28  	wait   sync.WaitGroup
    29  	lock   sync.Mutex
    30  	errors []error
    31  }
    32  
    33  // Submit submits a task for execution on the ErrorWaiter.
    34  //
    35  // The function returns immediately.
    36  func (ew *ErrorWaiter) Submit(f func() error) {
    37  	ew.wait.Add(1)
    38  	go func() {
    39  		defer ew.wait.Done()
    40  		if err := f(); err != nil {
    41  			ew.lock.Lock()
    42  			ew.errors = append(ew.errors, err)
    43  			ew.lock.Unlock()
    44  		}
    45  	}()
    46  }
    47  
    48  // Wait waits until all submitted tasks have finished and returns a list of
    49  // all errors that occurred during task execution in no particular order.
    50  func (ew *ErrorWaiter) Wait() []error {
    51  	ew.wait.Wait()
    52  	return ew.errors
    53  }