mirror of
https://github.com/go-gitea/gitea
synced 2024-12-25 06:25:02 +01:00
ccb3851281
When using the main branch, I found that some changed code didn't have comments. This PR adds some comments.
102 lines
3.6 KiB
Go
102 lines
3.6 KiB
Go
// Copyright 2022 The Gitea Authors. All rights reserved.
|
|
// SPDX-License-Identifier: MIT
|
|
|
|
package dbfs
|
|
|
|
import (
|
|
"context"
|
|
"os"
|
|
|
|
"code.gitea.io/gitea/models/db"
|
|
)
|
|
|
|
/*
|
|
The reasons behind the DBFS (database-filesystem) package:
|
|
When a Gitea action is running, the Gitea action server should collect and store all the logs.
|
|
|
|
The requirements are:
|
|
* The running logs must be stored across the cluster if the Gitea servers are deployed as a cluster.
|
|
* The logs will be archived to Object Storage (S3/MinIO, etc.) after a period of time.
|
|
* The Gitea action UI should be able to render the running logs and the archived logs.
|
|
|
|
Some possible solutions for the running logs:
|
|
* [Not ideal] Using local temp file: it can not be shared across the cluster.
|
|
* [Not ideal] Using shared file in the filesystem of git repository: although at the moment, the Gitea cluster's
|
|
git repositories must be stored in a shared filesystem, in the future, Gitea may need a dedicated Git Service Server
|
|
to decouple the shared filesystem. Then the action logs will become a blocker.
|
|
* [Not ideal] Record the logs in a database table line by line: it has a couple of problems:
|
|
- It's difficult to make multiple increasing sequence (log line number) for different databases.
|
|
- The database table will have a lot of rows and be affected by the big-table performance problem.
|
|
- It's difficult to load logs by using the same interface as other storages.
|
|
- It's difficult to calculate the size of the logs.
|
|
|
|
The DBFS solution:
|
|
* It can be used in a cluster.
|
|
* It can share the same interface (Read/Write/Seek) as other storages.
|
|
* It's very friendly to database because it only needs to store much fewer rows than the log-line solution.
|
|
* In the future, when Gitea action needs to limit the log size (other CI/CD services also do so), it's easier to calculate the log file size.
|
|
* Even sometimes the UI needs to render the tailing lines, the tailing lines can be found be counting the "\n" from the end of the file by seek.
|
|
The seeking and finding is not the fastest way, but it's still acceptable and won't affect the performance too much.
|
|
*/
|
|
|
|
type dbfsMeta struct {
|
|
ID int64 `xorm:"pk autoincr"`
|
|
FullPath string `xorm:"VARCHAR(500) UNIQUE NOT NULL"`
|
|
BlockSize int64 `xorm:"BIGINT NOT NULL"`
|
|
FileSize int64 `xorm:"BIGINT NOT NULL"`
|
|
CreateTimestamp int64 `xorm:"BIGINT NOT NULL"`
|
|
ModifyTimestamp int64 `xorm:"BIGINT NOT NULL"`
|
|
}
|
|
|
|
type dbfsData struct {
|
|
ID int64 `xorm:"pk autoincr"`
|
|
Revision int64 `xorm:"BIGINT NOT NULL"`
|
|
MetaID int64 `xorm:"BIGINT index(meta_offset) NOT NULL"`
|
|
BlobOffset int64 `xorm:"BIGINT index(meta_offset) NOT NULL"`
|
|
BlobSize int64 `xorm:"BIGINT NOT NULL"`
|
|
BlobData []byte `xorm:"BLOB NOT NULL"`
|
|
}
|
|
|
|
func init() {
|
|
db.RegisterModel(new(dbfsMeta))
|
|
db.RegisterModel(new(dbfsData))
|
|
}
|
|
|
|
func OpenFile(ctx context.Context, name string, flag int) (File, error) {
|
|
f, err := newDbFile(ctx, name)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
err = f.open(flag)
|
|
if err != nil {
|
|
_ = f.Close()
|
|
return nil, err
|
|
}
|
|
return f, nil
|
|
}
|
|
|
|
func Open(ctx context.Context, name string) (File, error) {
|
|
return OpenFile(ctx, name, os.O_RDONLY)
|
|
}
|
|
|
|
func Create(ctx context.Context, name string) (File, error) {
|
|
return OpenFile(ctx, name, os.O_RDWR|os.O_CREATE|os.O_TRUNC)
|
|
}
|
|
|
|
func Rename(ctx context.Context, oldPath, newPath string) error {
|
|
f, err := newDbFile(ctx, oldPath)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
defer f.Close()
|
|
return f.renameTo(newPath)
|
|
}
|
|
|
|
func Remove(ctx context.Context, name string) error {
|
|
f, err := newDbFile(ctx, name)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
defer f.Close()
|
|
return f.delete()
|
|
}
|