在过go 的几天里,我一直试图通过重构我的一个命令行实用程序来改变Golang中的并发性,但我被卡住了.
Here's原始代码(主分支).
Here's并发分支(x_并发分支).
当我使用go run jira_open_comment_emailer.go
执行并发代码时,如果将JIRA问题添加到通道here,则defer wg.Done()
永远不会执行,这会导致我的wg.Wait()
永远挂起.
我的 idea 是,我有大量的JIRA问题,我想 for each 问题衍生一个goroutine,看看它是否有我需要回复的 comments .如果是的话,我想把它添加到某种 struct 中(经过一些研究,我 Select 了一个频道),我可以在以后像排队一样阅读,以建立一个邮箱提醒.
以下是代码的相关部分:
// Given an issue, determine if it has an open comment
// Returns true if there is an open comment on the issue, otherwise false
func getAndProcessComments(issue Issue, channel chan<- Issue, wg *sync.WaitGroup) {
// Decrement the wait counter when the function returns
defer wg.Done()
needsReply := false
// Loop over the comments in the issue
for _, comment := range issue.Fields.Comment.Comments {
commentMatched, err := regexp.MatchString("~"+config.JIRAUsername, comment.Body)
checkError("Failed to regex match against comment body", err)
if commentMatched {
needsReply = true
}
if comment.Author.Name == config.JIRAUsername {
needsReply = false
}
}
// Only add the issue to the channel if it needs a reply
if needsReply == true {
// This never allows the defered wg.Done() to execute?
channel <- issue
}
}
func main() {
start := time.Now()
// This retrieves all issues in a search from JIRA
allIssues := getFullIssueList()
// Initialize a wait group
var wg sync.WaitGroup
// Set the number of waits to the number of issues to process
wg.Add(len(allIssues))
// Create a channel to store issues that need a reply
channel := make(chan Issue)
for _, issue := range allIssues {
go getAndProcessComments(issue, channel, &wg)
}
// Block until all of my goroutines have processed their issues.
wg.Wait()
// Only send an email if the channel has one or more issues
if len(channel) > 0 {
sendEmail(channel)
}
fmt.Printf("Script ran in %s", time.Since(start))
}