feat(github_release): add GitHub Release driver

drivers/all.go

@@ -25,6 +25,7 @@ import (
 	_ "github.com/alist-org/alist/v3/drivers/febbox"
 	_ "github.com/alist-org/alist/v3/drivers/ftp"
 	_ "github.com/alist-org/alist/v3/drivers/github"
+	_ "github.com/alist-org/alist/v3/drivers/github_release"
 	_ "github.com/alist-org/alist/v3/drivers/google_drive"
 	_ "github.com/alist-org/alist/v3/drivers/google_photo"
 	_ "github.com/alist-org/alist/v3/drivers/halalcloud"

drivers/github_release/backoff.go

@@ -0,0 +1,45 @@
+package template
+
+import (
+	"math/rand"
+	"time"
+)
+
+const (
+	initialRetryInterval = 500 * time.Millisecond
+	maxInterval          = 1 * time.Minute
+	maxElapsedTime       = 15 * time.Minute
+	randomizationFactor  = 0.5
+	multiplier           = 1.5
+)
+
+// Backoff 提供了确定在重试操作之前等待的时间算法
+type Backoff struct {
+	interval    time.Duration
+	elapsedTime time.Duration
+}
+
+// Pause 返回重试操作之前等待的时间量，如果可以再次尝试则返回 true，否则返回 false，表示操作应该被放弃。
+func (b *Backoff) Pause() (time.Duration, bool) {
+	if b.interval == 0 {
+		// first time
+		b.interval = initialRetryInterval
+		b.elapsedTime = 0
+	}
+
+	// interval from [1 - randomizationFactor, 1 + randomizationFactor)
+	randomizedInterval := time.Duration((rand.Float64()*(2*randomizationFactor) + (1 - randomizationFactor)) * float64(b.interval))
+	b.elapsedTime += randomizedInterval
+
+	if b.elapsedTime > maxElapsedTime {
+		return 0, false
+	}
+
+	// 将间隔增加到间隔上限
+	b.interval = time.Duration(float64(b.interval) * multiplier)
+	if b.interval > maxInterval {
+		b.interval = maxInterval
+	}
+
+	return randomizedInterval, true
+}

drivers/github_release/backoff_test.go

@@ -0,0 +1,37 @@
+package template
+
+import (
+	"testing"
+	"time"
+)
+
+func TestBackoffMultiple(t *testing.T) {
+	b := &Backoff{}
+	for i := 0; i < 19; i++ {
+		p, ok := b.Pause()
+		t.Logf("iteration %d pausing for %s", i, p)
+		if !ok {
+			t.Fatalf("hit the pause timeout after %d pauses", i)
+		}
+	}
+}
+
+func TestBackoffTimeout(t *testing.T) {
+	var elapsed time.Duration
+	b := &Backoff{}
+	for i := 0; i < 40; i++ {
+		p, ok := b.Pause()
+		elapsed += p
+		t.Logf("iteration %d pausing for %s (total %s)", i, p, elapsed)
+		if !ok {
+			break
+		}
+	}
+	if _, ok := b.Pause(); ok {
+		t.Fatalf("did not hit the pause timeout")
+	}
+
+	if elapsed > maxElapsedTime {
+		t.Fatalf("waited too long: %s > %s", elapsed, maxElapsedTime)
+	}
+}

drivers/github_release/driver.go

@@ -0,0 +1,168 @@
+package template
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"strconv"
+	"strings"
+
+	"github.com/alist-org/alist/v3/internal/conf"
+	"github.com/alist-org/alist/v3/internal/driver"
+	"github.com/alist-org/alist/v3/internal/errs"
+	"github.com/alist-org/alist/v3/internal/model"
+	"github.com/pkg/errors"
+)
+
+type GithubRelease struct {
+	model.Storage
+	Addition
+
+	api  *ApiContext
+	repo repository
+}
+
+func (d *GithubRelease) Config() driver.Config {
+	return config
+}
+
+func (d *GithubRelease) GetAddition() driver.Additional {
+	return &d.Addition
+}
+
+func (d *GithubRelease) Init(ctx context.Context) error {
+	token := d.Addition.Token
+	if token == "" {
+		return errs.EmptyToken
+	}
+
+	if d.Addition.MaxReleases < 1 {
+		return errors.New("max_releases must be greater than 0")
+	}
+
+	if d.Addition.MaxReleases > 100 {
+		d.Addition.MaxReleases = 100
+	}
+
+	d.api = NewApiContext(token, nil)
+
+	repo, err := newRepository(d.Addition.Repo)
+	if err != nil {
+		return err
+	}
+	d.repo = repo
+
+	return nil
+}
+
+// Drop Delete this driver
+func (d *GithubRelease) Drop(ctx context.Context) error {
+	return nil
+}
+
+func (d *GithubRelease) List(ctx context.Context, dir model.Obj, args model.ListArgs) ([]model.Obj, error) {
+	repo, err := newRepository(d.Addition.Repo)
+	if err != nil {
+		return nil, err
+	}
+
+	// 判断 dir 是不是挂在点。如果 dir 是挂载点，则返回所有的 release；
+	// 如果 dir 不是挂载点，则返回 dir 下的 release。
+	if dir.GetPath() == "" {
+		releases, err := d.api.GetReleases(repo, d.Addition.MaxReleases)
+		if err != nil {
+			return nil, err
+		}
+		return releases, nil
+	}
+
+	idStr := dir.GetID()
+	id, err := strconv.ParseInt(idStr, 10, 64)
+	if err != nil {
+		return nil, errors.Wrapf(err, "list release %s failed, id is not a number", idStr)
+	}
+
+	release, err := d.api.GetRelease(repo, id)
+	if err != nil {
+		return nil, err
+	}
+
+	return release.Children()
+}
+
+func (d *GithubRelease) proxyDownload(file model.Obj, args model.LinkArgs) bool {
+	if d.Config().MustProxy() || d.GetStorage().WebProxy {
+		return true
+	}
+
+	req := args.HttpReq
+	if args.HttpReq != nil &&
+		req.URL != nil &&
+		strings.HasPrefix(req.URL.Path, fmt.Sprintf("/p%s", d.GetStorage().MountPath)) {
+		return true
+	}
+
+	return false
+}
+
+func (d *GithubRelease) Link(ctx context.Context, file model.Obj, args model.LinkArgs) (*model.Link, error) {
+	idStr := file.GetID()
+	id, err := strconv.ParseInt(idStr, 10, 64)
+	if err != nil {
+		return nil, errors.Wrapf(err, "get link of file %s failed, id is not a number", idStr)
+	}
+	asset, err := d.api.GetReleaseAsset(d.repo, id)
+	if err != nil {
+		return nil, err
+	}
+
+	if d.proxyDownload(file, args) {
+
+		header := http.Header{
+			"User-Agent": {"Alist/" + conf.VERSION},
+			"Accept":     {"application/octet-stream"},
+		}
+		d.api.SetAuthHeader(header)
+
+		return &model.Link{
+			URL:    asset.URL,
+			Header: header,
+		}, nil
+	}
+
+	return &model.Link{
+		URL: asset.BrowserDownloadURL,
+	}, nil
+
+}
+
+func (d *GithubRelease) MakeDir(ctx context.Context, parentDir model.Obj, dirName string) (model.Obj, error) {
+	return nil, errs.NotSupport
+}
+
+func (d *GithubRelease) Move(ctx context.Context, srcObj, dstDir model.Obj) (model.Obj, error) {
+	return nil, errs.NotSupport
+}
+
+func (d *GithubRelease) Rename(ctx context.Context, srcObj model.Obj, newName string) (model.Obj, error) {
+	// TODO rename obj, optional
+	return nil, errs.NotImplement
+}
+
+func (d *GithubRelease) Copy(ctx context.Context, srcObj, dstDir model.Obj) (model.Obj, error) {
+	return nil, errs.NotSupport
+}
+
+func (d *GithubRelease) Remove(ctx context.Context, obj model.Obj) error {
+	return errs.NotSupport
+}
+
+func (d *GithubRelease) Put(ctx context.Context, dstDir model.Obj, stream model.FileStreamer, up driver.UpdateProgress) (model.Obj, error) {
+	return nil, errs.NotSupport
+}
+
+//func (d *Template) Other(ctx context.Context, args model.OtherArgs) (interface{}, error) {
+//	return nil, errs.NotSupport
+//}
+
+var _ driver.Driver = (*GithubRelease)(nil)