gitea/modules/indexer/issues/indexer.go
wxiaoguang 6f9c278559
Rewrite queue (#24505)
# ⚠️ Breaking

Many deprecated queue config options are removed (actually, they should
have been removed in 1.18/1.19).

If you see the fatal message when starting Gitea: "Please update your
app.ini to remove deprecated config options", please follow the error
messages to remove these options from your app.ini.

Example:

```
2023/05/06 19:39:22 [E] Removed queue option: `[indexer].ISSUE_INDEXER_QUEUE_TYPE`. Use new options in `[queue.issue_indexer]`
2023/05/06 19:39:22 [E] Removed queue option: `[indexer].UPDATE_BUFFER_LEN`. Use new options in `[queue.issue_indexer]`
2023/05/06 19:39:22 [F] Please update your app.ini to remove deprecated config options
```

Many options in `[queue]` are are dropped, including:
`WRAP_IF_NECESSARY`, `MAX_ATTEMPTS`, `TIMEOUT`, `WORKERS`,
`BLOCK_TIMEOUT`, `BOOST_TIMEOUT`, `BOOST_WORKERS`, they can be removed
from app.ini.

# The problem

The old queue package has some legacy problems:

* complexity: I doubt few people could tell how it works.
* maintainability: Too many channels and mutex/cond are mixed together,
too many different structs/interfaces depends each other.
* stability: due to the complexity & maintainability, sometimes there
are strange bugs and difficult to debug, and some code doesn't have test
(indeed some code is difficult to test because a lot of things are mixed
together).
* general applicability: although it is called "queue", its behavior is
not a well-known queue.
* scalability: it doesn't seem easy to make it work with a cluster
without breaking its behaviors.

It came from some very old code to "avoid breaking", however, its
technical debt is too heavy now. It's a good time to introduce a better
"queue" package.

# The new queue package

It keeps using old config and concept as much as possible.

* It only contains two major kinds of concepts:
    * The "base queue": channel, levelqueue, redis
* They have the same abstraction, the same interface, and they are
tested by the same testing code.
* The "WokerPoolQueue", it uses the "base queue" to provide "worker
pool" function, calls the "handler" to process the data in the base
queue.
* The new code doesn't do "PushBack"
* Think about a queue with many workers, the "PushBack" can't guarantee
the order for re-queued unhandled items, so in new code it just does
"normal push"
* The new code doesn't do "pause/resume"
* The "pause/resume" was designed to handle some handler's failure: eg:
document indexer (elasticsearch) is down
* If a queue is paused for long time, either the producers blocks or the
new items are dropped.
* The new code doesn't do such "pause/resume" trick, it's not a common
queue's behavior and it doesn't help much.
* If there are unhandled items, the "push" function just blocks for a
few seconds and then re-queue them and retry.
* The new code doesn't do "worker booster"
* Gitea's queue's handlers are light functions, the cost is only the
go-routine, so it doesn't make sense to "boost" them.
* The new code only use "max worker number" to limit the concurrent
workers.
* The new "Push" never blocks forever
* Instead of creating more and more blocking goroutines, return an error
is more friendly to the server and to the end user.

There are more details in code comments: eg: the "Flush" problem, the
strange "code.index" hanging problem, the "immediate" queue problem.

Almost ready for review.

TODO:

* [x] add some necessary comments during review
* [x] add some more tests if necessary
* [x] update documents and config options
* [x] test max worker / active worker
* [x] re-run the CI tasks to see whether any test is flaky
* [x] improve the `handleOldLengthConfiguration` to provide more
friendly messages
* [x] fine tune default config values (eg: length?)

## Code coverage:

![image](https://user-images.githubusercontent.com/2114189/236620635-55576955-f95d-4810-b12f-879026a3afdf.png)
2023-05-08 19:49:59 +08:00

394 lines
12 KiB
Go

// Copyright 2018 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package issues
import (
"context"
"fmt"
"os"
"runtime/pprof"
"sync"
"time"
"code.gitea.io/gitea/models/db"
issues_model "code.gitea.io/gitea/models/issues"
repo_model "code.gitea.io/gitea/models/repo"
"code.gitea.io/gitea/modules/graceful"
"code.gitea.io/gitea/modules/log"
"code.gitea.io/gitea/modules/process"
"code.gitea.io/gitea/modules/queue"
"code.gitea.io/gitea/modules/setting"
"code.gitea.io/gitea/modules/util"
)
// IndexerData data stored in the issue indexer
type IndexerData struct {
ID int64 `json:"id"`
RepoID int64 `json:"repo_id"`
Title string `json:"title"`
Content string `json:"content"`
Comments []string `json:"comments"`
IsDelete bool `json:"is_delete"`
IDs []int64 `json:"ids"`
}
// Match represents on search result
type Match struct {
ID int64 `json:"id"`
Score float64 `json:"score"`
}
// SearchResult represents search results
type SearchResult struct {
Total int64
Hits []Match
}
// Indexer defines an interface to indexer issues contents
type Indexer interface {
Init() (bool, error)
Ping() bool
Index(issue []*IndexerData) error
Delete(ids ...int64) error
Search(ctx context.Context, kw string, repoIDs []int64, limit, start int) (*SearchResult, error)
Close()
}
type indexerHolder struct {
indexer Indexer
mutex sync.RWMutex
cond *sync.Cond
cancelled bool
}
func newIndexerHolder() *indexerHolder {
h := &indexerHolder{}
h.cond = sync.NewCond(h.mutex.RLocker())
return h
}
func (h *indexerHolder) cancel() {
h.mutex.Lock()
defer h.mutex.Unlock()
h.cancelled = true
h.cond.Broadcast()
}
func (h *indexerHolder) set(indexer Indexer) {
h.mutex.Lock()
defer h.mutex.Unlock()
h.indexer = indexer
h.cond.Broadcast()
}
func (h *indexerHolder) get() Indexer {
h.mutex.RLock()
defer h.mutex.RUnlock()
if h.indexer == nil && !h.cancelled {
h.cond.Wait()
}
return h.indexer
}
var (
// issueIndexerQueue queue of issue ids to be updated
issueIndexerQueue *queue.WorkerPoolQueue[*IndexerData]
holder = newIndexerHolder()
)
// InitIssueIndexer initialize issue indexer, syncReindex is true then reindex until
// all issue index done.
func InitIssueIndexer(syncReindex bool) {
ctx, _, finished := process.GetManager().AddTypedContext(context.Background(), "Service: IssueIndexer", process.SystemProcessType, false)
waitChannel := make(chan time.Duration, 1)
// Create the Queue
switch setting.Indexer.IssueType {
case "bleve", "elasticsearch", "meilisearch":
handler := func(items ...*IndexerData) (unhandled []*IndexerData) {
indexer := holder.get()
if indexer == nil {
log.Error("Issue indexer handler: unable to get indexer.")
return items
}
toIndex := make([]*IndexerData, 0, len(items))
for _, indexerData := range items {
log.Trace("IndexerData Process: %d %v %t", indexerData.ID, indexerData.IDs, indexerData.IsDelete)
if indexerData.IsDelete {
if err := indexer.Delete(indexerData.IDs...); err != nil {
log.Error("Issue indexer handler: failed to from index: %v Error: %v", indexerData.IDs, err)
if !indexer.Ping() {
log.Error("Issue indexer handler: indexer is unavailable when deleting")
unhandled = append(unhandled, indexerData)
}
}
continue
}
toIndex = append(toIndex, indexerData)
}
if err := indexer.Index(toIndex); err != nil {
log.Error("Error whilst indexing: %v Error: %v", toIndex, err)
if !indexer.Ping() {
log.Error("Issue indexer handler: indexer is unavailable when indexing")
unhandled = append(unhandled, toIndex...)
}
}
return unhandled
}
issueIndexerQueue = queue.CreateSimpleQueue("issue_indexer", handler)
if issueIndexerQueue == nil {
log.Fatal("Unable to create issue indexer queue")
}
default:
issueIndexerQueue = queue.CreateSimpleQueue[*IndexerData]("issue_indexer", nil)
}
// Create the Indexer
go func() {
pprof.SetGoroutineLabels(ctx)
start := time.Now()
log.Info("PID %d: Initializing Issue Indexer: %s", os.Getpid(), setting.Indexer.IssueType)
var populate bool
switch setting.Indexer.IssueType {
case "bleve":
defer func() {
if err := recover(); err != nil {
log.Error("PANIC whilst initializing issue indexer: %v\nStacktrace: %s", err, log.Stack(2))
log.Error("The indexer files are likely corrupted and may need to be deleted")
log.Error("You can completely remove the %q directory to make Gitea recreate the indexes", setting.Indexer.IssuePath)
holder.cancel()
log.Fatal("PID: %d Unable to initialize the Bleve Issue Indexer at path: %s Error: %v", os.Getpid(), setting.Indexer.IssuePath, err)
}
}()
issueIndexer := NewBleveIndexer(setting.Indexer.IssuePath)
exist, err := issueIndexer.Init()
if err != nil {
holder.cancel()
log.Fatal("Unable to initialize Bleve Issue Indexer at path: %s Error: %v", setting.Indexer.IssuePath, err)
}
populate = !exist
holder.set(issueIndexer)
graceful.GetManager().RunAtTerminate(func() {
log.Debug("Closing issue indexer")
issueIndexer := holder.get()
if issueIndexer != nil {
issueIndexer.Close()
}
finished()
log.Info("PID: %d Issue Indexer closed", os.Getpid())
})
log.Debug("Created Bleve Indexer")
case "elasticsearch":
graceful.GetManager().RunWithShutdownFns(func(_, atTerminate func(func())) {
pprof.SetGoroutineLabels(ctx)
issueIndexer, err := NewElasticSearchIndexer(setting.Indexer.IssueConnStr, setting.Indexer.IssueIndexerName)
if err != nil {
log.Fatal("Unable to initialize Elastic Search Issue Indexer at connection: %s Error: %v", setting.Indexer.IssueConnStr, err)
}
exist, err := issueIndexer.Init()
if err != nil {
log.Fatal("Unable to issueIndexer.Init with connection %s Error: %v", setting.Indexer.IssueConnStr, err)
}
populate = !exist
holder.set(issueIndexer)
atTerminate(finished)
})
case "db":
issueIndexer := &DBIndexer{}
holder.set(issueIndexer)
graceful.GetManager().RunAtTerminate(finished)
case "meilisearch":
graceful.GetManager().RunWithShutdownFns(func(_, atTerminate func(func())) {
pprof.SetGoroutineLabels(ctx)
issueIndexer, err := NewMeilisearchIndexer(setting.Indexer.IssueConnStr, setting.Indexer.IssueConnAuth, setting.Indexer.IssueIndexerName)
if err != nil {
log.Fatal("Unable to initialize Meilisearch Issue Indexer at connection: %s Error: %v", setting.Indexer.IssueConnStr, err)
}
exist, err := issueIndexer.Init()
if err != nil {
log.Fatal("Unable to issueIndexer.Init with connection %s Error: %v", setting.Indexer.IssueConnStr, err)
}
populate = !exist
holder.set(issueIndexer)
atTerminate(finished)
})
default:
holder.cancel()
log.Fatal("Unknown issue indexer type: %s", setting.Indexer.IssueType)
}
// Start processing the queue
go graceful.GetManager().RunWithShutdownFns(issueIndexerQueue.Run)
// Populate the index
if populate {
if syncReindex {
graceful.GetManager().RunWithShutdownContext(populateIssueIndexer)
} else {
go graceful.GetManager().RunWithShutdownContext(populateIssueIndexer)
}
}
waitChannel <- time.Since(start)
close(waitChannel)
}()
if syncReindex {
select {
case <-waitChannel:
case <-graceful.GetManager().IsShutdown():
}
} else if setting.Indexer.StartupTimeout > 0 {
go func() {
pprof.SetGoroutineLabels(ctx)
timeout := setting.Indexer.StartupTimeout
if graceful.GetManager().IsChild() && setting.GracefulHammerTime > 0 {
timeout += setting.GracefulHammerTime
}
select {
case duration := <-waitChannel:
log.Info("Issue Indexer Initialization took %v", duration)
case <-graceful.GetManager().IsShutdown():
log.Warn("Shutdown occurred before issue index initialisation was complete")
case <-time.After(timeout):
issueIndexerQueue.ShutdownWait(5 * time.Second)
log.Fatal("Issue Indexer Initialization timed-out after: %v", timeout)
}
}()
}
}
// populateIssueIndexer populate the issue indexer with issue data
func populateIssueIndexer(ctx context.Context) {
ctx, _, finished := process.GetManager().AddTypedContext(ctx, "Service: PopulateIssueIndexer", process.SystemProcessType, true)
defer finished()
for page := 1; ; page++ {
select {
case <-ctx.Done():
log.Warn("Issue Indexer population shutdown before completion")
return
default:
}
repos, _, err := repo_model.SearchRepositoryByName(ctx, &repo_model.SearchRepoOptions{
ListOptions: db.ListOptions{Page: page, PageSize: repo_model.RepositoryListDefaultPageSize},
OrderBy: db.SearchOrderByID,
Private: true,
Collaborate: util.OptionalBoolFalse,
})
if err != nil {
log.Error("SearchRepositoryByName: %v", err)
continue
}
if len(repos) == 0 {
log.Debug("Issue Indexer population complete")
return
}
for _, repo := range repos {
select {
case <-ctx.Done():
log.Info("Issue Indexer population shutdown before completion")
return
default:
}
UpdateRepoIndexer(ctx, repo)
}
}
}
// UpdateRepoIndexer add/update all issues of the repositories
func UpdateRepoIndexer(ctx context.Context, repo *repo_model.Repository) {
is, err := issues_model.Issues(ctx, &issues_model.IssuesOptions{
RepoID: repo.ID,
IsClosed: util.OptionalBoolNone,
IsPull: util.OptionalBoolNone,
})
if err != nil {
log.Error("Issues: %v", err)
return
}
if err = issues_model.IssueList(is).LoadDiscussComments(ctx); err != nil {
log.Error("LoadDiscussComments: %v", err)
return
}
for _, issue := range is {
UpdateIssueIndexer(issue)
}
}
// UpdateIssueIndexer add/update an issue to the issue indexer
func UpdateIssueIndexer(issue *issues_model.Issue) {
var comments []string
for _, comment := range issue.Comments {
if comment.Type == issues_model.CommentTypeComment {
comments = append(comments, comment.Content)
}
}
indexerData := &IndexerData{
ID: issue.ID,
RepoID: issue.RepoID,
Title: issue.Title,
Content: issue.Content,
Comments: comments,
}
log.Debug("Adding to channel: %v", indexerData)
if err := issueIndexerQueue.Push(indexerData); err != nil {
log.Error("Unable to push to issue indexer: %v: Error: %v", indexerData, err)
}
}
// DeleteRepoIssueIndexer deletes repo's all issues indexes
func DeleteRepoIssueIndexer(ctx context.Context, repo *repo_model.Repository) {
var ids []int64
ids, err := issues_model.GetIssueIDsByRepoID(ctx, repo.ID)
if err != nil {
log.Error("GetIssueIDsByRepoID failed: %v", err)
return
}
if len(ids) == 0 {
return
}
indexerData := &IndexerData{
IDs: ids,
IsDelete: true,
}
if err := issueIndexerQueue.Push(indexerData); err != nil {
log.Error("Unable to push to issue indexer: %v: Error: %v", indexerData, err)
}
}
// SearchIssuesByKeyword search issue ids by keywords and repo id
// WARNNING: You have to ensure user have permission to visit repoIDs' issues
func SearchIssuesByKeyword(ctx context.Context, repoIDs []int64, keyword string) ([]int64, error) {
var issueIDs []int64
indexer := holder.get()
if indexer == nil {
log.Error("SearchIssuesByKeyword(): unable to get indexer!")
return nil, fmt.Errorf("unable to get issue indexer")
}
res, err := indexer.Search(ctx, keyword, repoIDs, 50, 0)
if err != nil {
return nil, err
}
for _, r := range res.Hits {
issueIDs = append(issueIDs, r.ID)
}
return issueIDs, nil
}
// IsAvailable checks if issue indexer is available
func IsAvailable() bool {
indexer := holder.get()
if indexer == nil {
log.Error("IsAvailable(): unable to get indexer!")
return false
}
return indexer.Ping()
}