github.com/pingcap/tiflow@v0.0.0-20240520035814-5bf52d54e205/pkg/util/runnable.go (about)

     1  // Copyright 2023 PingCAP, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // See the License for the specific language governing permissions and
    12  // limitations under the License.
    13  
    14  package util
    15  
    16  import (
    17  	"context"
    18  )
    19  
    20  // Runnable is for handling sub components in a unified way.
    21  //
    22  // For example:
    23  // r := createRunable()
    24  // ctx, cancel := context.WithCancel(context.Background())
    25  // go func() { handleError(r.Run(ctx)) }()
    26  // r.WaitForReady()
    27  // cancel()
    28  // r.Close()
    29  type Runnable interface {
    30  	// Run all sub goroutines and block the current one. If an error occurs
    31  	// in any sub goroutine, return it and cancel all others.
    32  	//
    33  	// Generally a Runnable object can have some internal resources, like file
    34  	// descriptors, channels or memory buffers. Those resources may be still
    35  	// necessary by other components after this Runnable is returned. We can use
    36  	// Close to release them.
    37  	//
    38  	// `warnings` is used to retrieve internal warnings generated when running.
    39  	Run(ctx context.Context, warnings ...chan<- error) error
    40  	// WaitForReady blocks the current goroutine until `Run` initializes itself.
    41  	WaitForReady(ctx context.Context)
    42  	// Close all internal resources synchronously.
    43  	Close()
    44  }