Make the Mirror Queue a queue (go-gitea#17326)

Convert the old mirror syncing queue to the more modern queue format.

Fix a bug in the from the repo-archive queue PR - the assumption was made that uniqueness could be enforced with by checking equality in a map in channel unique queues - however this only works for primitive types - which was the initial intention but is an imperfect. This is fixed by marshalling the data and placing the martialled data in the unique map instead.

The documentation is also updated to add information about the deprecated configuration values.

Signed-off-by: Andrew Thornton <art27@cantab.net>

Author: zeripath

Diff for: custom/conf/app.example.ini

@@ -769,10 +769,10 @@ PATH =
 ;; Global limit of repositories per user, applied at creation time. -1 means no limit
 ;MAX_CREATION_LIMIT = -1
 ;;
-;; Mirror sync queue length, increase if mirror syncing starts hanging
+;; Mirror sync queue length, increase if mirror syncing starts hanging (DEPRECATED: please use [queue.mirror] LENGTH instead)
 ;MIRROR_QUEUE_LENGTH = 1000
 ;;
-;; Patch test queue length, increase if pull request patch testing starts hanging
+;; Patch test queue length, increase if pull request patch testing starts hanging (DEPRECATED: please use [queue.pr_patch_checker] LENGTH instead)
 ;PULL_REQUEST_QUEUE_LENGTH = 1000
 ;;
 ;; Preferred Licenses to place at the top of the List

Diff for: docs/content/doc/advanced/config-cheat-sheet.en-us.md

@@ -54,10 +54,10 @@ Values containing `#` or `;` must be quoted using `` ` `` or `"""`.
 - `DEFAULT_PUSH_CREATE_PRIVATE`: **true**: Default private when creating a new repository with push-to-create.
 - `MAX_CREATION_LIMIT`: **-1**: Global maximum creation limit of repositories per user,
    `-1` means no limit.
-- `PULL_REQUEST_QUEUE_LENGTH`: **1000**: Length of pull request patch test queue, make it
+- `PULL_REQUEST_QUEUE_LENGTH`: **1000**: Length of pull request patch test queue, make it. **DEPRECATED** use `LENGTH` in `[queue.pr_patch_checker]`.
    as large as possible. Use caution when editing this value.
 - `MIRROR_QUEUE_LENGTH`: **1000**: Patch test queue length, increase if pull request patch
-   testing starts hanging.
+   testing starts hanging. **DEPRECATED** use `LENGTH` in `[queue.mirror]`.
 - `PREFERRED_LICENSES`: **Apache License 2.0,MIT License**: Preferred Licenses to place at
    the top of the list. Name must match file name in options/license or custom/options/license.
 - `DISABLE_HTTP_GIT`: **false**: Disable the ability to interact with repositories over the
@@ -382,6 +382,8 @@ relation to port exhaustion.
 
 ## Queue (`queue` and `queue.*`)
 
+Configuration at `[queue]` will set defaults for queues with overrides for individual queues at `[queue.*]`. (However see below.)
+
 - `TYPE`: **persistable-channel**: General queue type, currently support: `persistable-channel` (uses a LevelDB internally), `channel`, `level`, `redis`, `dummy`
 - `DATADIR`: **queues/**: Base DataDir for storing persistent and level queues. `DATADIR` for individual queues can be set in `queue.name` sections but will default to `DATADIR/`**`common`**. (Previously each queue would default to `DATADIR/`**`name`**.)
 - `LENGTH`: **20**: Maximal queue size before channel queues block
@@ -400,6 +402,37 @@ relation to port exhaustion.
 - `BOOST_TIMEOUT`: **5m**: Boost workers will timeout after this long.
 - `BOOST_WORKERS`: **1** (v1.14 and before: **5**): This many workers will be added to the worker pool if there is a boost.
 
+Gitea creates the following non-unique queues:
+
+- `code_indexer`
+- `issue_indexer`
+- `notification-service`
+- `task`
+- `mail`
+- `push_update`
+
+And the following unique queues:
+
+- `repo_stats_update`
+- `repo-archive`
+- `mirror`
+- `pr_patch_checker`
+
+Certain queues have defaults that override the defaults set in `[queue]` (this occurs mostly to support older configuration):
+
+- `[queue.issue_indexer]`
+  - `TYPE` this will default to `[queue]` `TYPE` if it is set but if not it will appropriately convert `[indexer]` `ISSUE_INDEXER_QUEUE_TYPE` if that is set.
+  - `LENGTH` will default to `[indexer]` `UPDATE_BUFFER_LEN` if that is set.
+  - `BATCH_LENGTH` will default to `[indexer]` `ISSUE_INDEXER_QUEUE_BATCH_NUMBER` if that is set.
+  - `DATADIR` will default to `[indexer]` `ISSUE_INDEXER_QUEUE_DIR` if that is set.
+  - `CONN_STR` will default to `[indexer]` `ISSUE_INDEXER_QUEUE_CONN_STR` if that is set.
+- `[queue.mailer]`
+  - `LENGTH` will default to **100** or whatever `[mailer]` `SEND_BUFFER_LEN` is.
+- `[queue.pr_patch_checker]`
+  - `LENGTH` will default to **1000** or whatever `[repository]` `PULL_REQUEST_QUEUE_LENGTH` is.
+- `[queue.mirror]`
+  - `LENGTH` will default to **1000** or whatever `[repository]` `MIRROR_QUEUE_LENGTH` is.
+
 ## Admin (`admin`)
 
 - `DEFAULT_EMAIL_NOTIFICATIONS`: **enabled**: Default configuration for email notifications for users (user configurable). Options: enabled, onmention, disabled
@@ -588,7 +621,7 @@ Define allowed algorithms and their minimum key length (use -1 to disable a type
    command or full path).
 - `SENDMAIL_ARGS`: **_empty_**: Specify any extra sendmail arguments.
 - `SENDMAIL_TIMEOUT`: **5m**: default timeout for sending email through sendmail
-- `SEND_BUFFER_LEN`: **100**: Buffer length of mailing queue.
+- `SEND_BUFFER_LEN`: **100**: Buffer length of mailing queue. **DEPRECATED** use `LENGTH` in `[queue.mailer]`
 
 ## Cache (`cache`)
 

Diff for: modules/queue/unique_queue_channel.go

@@ -9,6 +9,7 @@ import (
 	"fmt"
 	"sync"
 
+	"code.gitea.io/gitea/modules/json"
 	"code.gitea.io/gitea/modules/log"
 )
 
@@ -29,7 +30,7 @@ type ChannelUniqueQueueConfiguration ChannelQueueConfiguration
 type ChannelUniqueQueue struct {
 	*WorkerPool
 	lock               sync.Mutex
-	table              map[Data]bool
+	table              map[string]bool
 	shutdownCtx        context.Context
 	shutdownCtxCancel  context.CancelFunc
 	terminateCtx       context.Context
@@ -54,7 +55,7 @@ func NewChannelUniqueQueue(handle HandlerFunc, cfg, exemplar interface{}) (Queue
 	shutdownCtx, shutdownCtxCancel := context.WithCancel(terminateCtx)
 
 	queue := &ChannelUniqueQueue{
-		table:              map[Data]bool{},
+		table:              map[string]bool{},
 		shutdownCtx:        shutdownCtx,
 		shutdownCtxCancel:  shutdownCtxCancel,
 		terminateCtx:       terminateCtx,
@@ -65,9 +66,13 @@ func NewChannelUniqueQueue(handle HandlerFunc, cfg, exemplar interface{}) (Queue
 	}
 	queue.WorkerPool = NewWorkerPool(func(data ...Data) {
 		for _, datum := range data {
+			// No error is possible here because PushFunc ensures that this can be marshalled
+			bs, _ := json.Marshal(datum)
+
 			queue.lock.Lock()
-			delete(queue.table, datum)
+			delete(queue.table, string(bs))
 			queue.lock.Unlock()
+
 			handle(datum)
 		}
 	}, config.WorkerPoolConfiguration)
@@ -94,23 +99,28 @@ func (q *ChannelUniqueQueue) PushFunc(data Data, fn func() error) error {
 	if !assignableTo(data, q.exemplar) {
 		return fmt.Errorf("Unable to assign data: %v to same type as exemplar: %v in queue: %s", data, q.exemplar, q.name)
 	}
+
+	bs, err := json.Marshal(data)
+	if err != nil {
+		return err
+	}
 	q.lock.Lock()
 	locked := true
 	defer func() {
 		if locked {
 			q.lock.Unlock()
 		}
 	}()
-	if _, ok := q.table[data]; ok {
+	if _, ok := q.table[string(bs)]; ok {
 		return ErrAlreadyInQueue
 	}
 	// FIXME: We probably need to implement some sort of limit here
 	// If the downstream queue blocks this table will grow without limit
-	q.table[data] = true
+	q.table[string(bs)] = true
 	if fn != nil {
 		err := fn()
 		if err != nil {
-			delete(q.table, data)
+			delete(q.table, string(bs))
 			return err
 		}
 	}
@@ -122,9 +132,14 @@ func (q *ChannelUniqueQueue) PushFunc(data Data, fn func() error) error {
 
 // Has checks if the data is in the queue
 func (q *ChannelUniqueQueue) Has(data Data) (bool, error) {
+	bs, err := json.Marshal(data)
+	if err != nil {
+		return false, err
+	}
+
 	q.lock.Lock()
 	defer q.lock.Unlock()
-	_, has := q.table[data]
+	_, has := q.table[string(bs)]
 	return has, nil
 }
 

Diff for: modules/setting/mailer.go

@@ -16,7 +16,6 @@ import (
 // Mailer represents mail service.
 type Mailer struct {
 	// Mailer
-	QueueLength     int
 	Name            string
 	From            string
 	FromName        string
@@ -54,7 +53,6 @@ func newMailService() {
 	}
 
 	MailService = &Mailer{
-		QueueLength:     sec.Key("SEND_BUFFER_LEN").MustInt(100),
 		Name:            sec.Key("NAME").MustString(AppName),
 		SendAsPlainText: sec.Key("SEND_AS_PLAIN_TEXT").MustBool(false),
 		MailerType:      sec.Key("MAILER_TYPE").In("", []string{"smtp", "sendmail", "dummy"}),

Diff for: modules/setting/queue.go

@@ -5,11 +5,12 @@
 package setting
 
 import (
-	"fmt"
 	"path/filepath"
+	"strconv"
 	"time"
 
 	"code.gitea.io/gitea/modules/log"
+	ini "gopkg.in/ini.v1"
 )
 
 // QueueSettings represent the settings for a queue from the ini
@@ -106,11 +107,8 @@ func NewQueueService() {
 
 	// Now handle the old issue_indexer configuration
 	section := Cfg.Section("queue.issue_indexer")
-	sectionMap := map[string]bool{}
-	for _, key := range section.Keys() {
-		sectionMap[key.Name()] = true
-	}
-	if _, ok := sectionMap["TYPE"]; !ok && defaultType == "" {
+	directlySet := toDirectlySetKeysMap(section)
+	if !directlySet["TYPE"] && defaultType == "" {
 		switch Indexer.IssueQueueType {
 		case LevelQueueType:
 			_, _ = section.NewKey("TYPE", "level")
@@ -125,37 +123,53 @@ func NewQueueService() {
 				Indexer.IssueQueueType)
 		}
 	}
-	if _, ok := sectionMap["LENGTH"]; !ok && Indexer.UpdateQueueLength != 0 {
-		_, _ = section.NewKey("LENGTH", fmt.Sprintf("%d", Indexer.UpdateQueueLength))
+	if !directlySet["LENGTH"] && Indexer.UpdateQueueLength != 0 {
+		_, _ = section.NewKey("LENGTH", strconv.Itoa(Indexer.UpdateQueueLength))
 	}
-	if _, ok := sectionMap["BATCH_LENGTH"]; !ok && Indexer.IssueQueueBatchNumber != 0 {
-		_, _ = section.NewKey("BATCH_LENGTH", fmt.Sprintf("%d", Indexer.IssueQueueBatchNumber))
+	if !directlySet["BATCH_LENGTH"] && Indexer.IssueQueueBatchNumber != 0 {
+		_, _ = section.NewKey("BATCH_LENGTH", strconv.Itoa(Indexer.IssueQueueBatchNumber))
 	}
-	if _, ok := sectionMap["DATADIR"]; !ok && Indexer.IssueQueueDir != "" {
+	if !directlySet["DATADIR"] && Indexer.IssueQueueDir != "" {
 		_, _ = section.NewKey("DATADIR", Indexer.IssueQueueDir)
 	}
-	if _, ok := sectionMap["CONN_STR"]; !ok && Indexer.IssueQueueConnStr != "" {
+	if !directlySet["CONN_STR"] && Indexer.IssueQueueConnStr != "" {
 		_, _ = section.NewKey("CONN_STR", Indexer.IssueQueueConnStr)
 	}
 
 	// Handle the old mailer configuration
-	section = Cfg.Section("queue.mailer")
-	sectionMap = map[string]bool{}
-	for _, key := range section.Keys() {
-		sectionMap[key.Name()] = true
-	}
-	if _, ok := sectionMap["LENGTH"]; !ok {
-		_, _ = section.NewKey("LENGTH", fmt.Sprintf("%d", Cfg.Section("mailer").Key("SEND_BUFFER_LEN").MustInt(100)))
-	}
+	handleOldLengthConfiguration("mailer", Cfg.Section("mailer").Key("SEND_BUFFER_LEN").MustInt(100))
 
 	// Handle the old test pull requests configuration
 	// Please note this will be a unique queue
-	section = Cfg.Section("queue.pr_patch_checker")
-	sectionMap = map[string]bool{}
+	handleOldLengthConfiguration("pr_patch_checker", Cfg.Section("repository").Key("PULL_REQUEST_QUEUE_LENGTH").MustInt(1000))
+
+	// Handle the old mirror queue configuration
+	// Please note this will be a unique queue
+	handleOldLengthConfiguration("mirror", Cfg.Section("repository").Key("MIRROR_QUEUE_LENGTH").MustInt(1000))
+}
+
+// handleOldLengthConfiguration allows fallback to older configuration. `[queue.name]` `LENGTH` will override this configuration, but
+// if that is left unset then we should fallback to the older configuration. (Except where the new length woul be <=0)
+func handleOldLengthConfiguration(queueName string, value int) {
+	// Don't override with 0
+	if value <= 0 {
+		return
+	}
+
+	section := Cfg.Section("queue." + queueName)
+	directlySet := toDirectlySetKeysMap(section)
+	if !directlySet["LENGTH"] {
+		_, _ = section.NewKey("LENGTH", strconv.Itoa(value))
+	}
+}
+
+// toDirectlySetKeysMap returns a bool map of keys directly set by this section
+// Note: we cannot use section.HasKey(...) as that will immediately set the Key if a parent section has the Key
+// but this section does not.
+func toDirectlySetKeysMap(section *ini.Section) map[string]bool {
+	sectionMap := map[string]bool{}
 	for _, key := range section.Keys() {
 		sectionMap[key.Name()] = true
 	}
-	if _, ok := sectionMap["LENGTH"]; !ok {
-		_, _ = section.NewKey("LENGTH", fmt.Sprintf("%d", Repository.PullRequestQueueLength))
-	}
+	return sectionMap
 }

Diff for: modules/setting/repository.go

@@ -29,8 +29,6 @@ var (
 		DefaultPrivate                          string
 		DefaultPushCreatePrivate                bool
 		MaxCreationLimit                        int
-		MirrorQueueLength                       int
-		PullRequestQueueLength                  int
 		PreferredLicenses                       []string
 		DisableHTTPGit                          bool
 		AccessControlAllowOrigin                string
@@ -142,8 +140,6 @@ var (
 		DefaultPrivate:                          RepoCreatingLastUserVisibility,
 		DefaultPushCreatePrivate:                true,
 		MaxCreationLimit:                        -1,
-		MirrorQueueLength:                       1000,
-		PullRequestQueueLength:                  1000,
 		PreferredLicenses:                       []string{"Apache License 2.0", "MIT License"},
 		DisableHTTPGit:                          false,
 		AccessControlAllowOrigin:                "",