Refactor routers directory (#15800)

* refactor routers directory

* move func used for web and api to common

* make corsHandler a function to prohibit side efects

* rm unused func

Co-authored-by: 6543 <6543@obermui.de>

routers/web/repo/download.go

@@ -0,0 +1,131 @@
+// Copyright 2014 The Gogs Authors. All rights reserved.
+// Copyright 2018 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package repo
+
+import (
+	"code.gitea.io/gitea/modules/context"
+	"code.gitea.io/gitea/modules/git"
+	"code.gitea.io/gitea/modules/httpcache"
+	"code.gitea.io/gitea/modules/lfs"
+	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/routers/common"
+)
+
+// ServeBlobOrLFS download a git.Blob redirecting to LFS if necessary
+func ServeBlobOrLFS(ctx *context.Context, blob *git.Blob) error {
+	if httpcache.HandleGenericETagCache(ctx.Req, ctx.Resp, `"`+blob.ID.String()+`"`) {
+		return nil
+	}
+
+	dataRc, err := blob.DataAsync()
+	if err != nil {
+		return err
+	}
+	closed := false
+	defer func() {
+		if closed {
+			return
+		}
+		if err = dataRc.Close(); err != nil {
+			log.Error("ServeBlobOrLFS: Close: %v", err)
+		}
+	}()
+
+	pointer, _ := lfs.ReadPointer(dataRc)
+	if pointer.IsValid() {
+		meta, _ := ctx.Repo.Repository.GetLFSMetaObjectByOid(pointer.Oid)
+		if meta == nil {
+			if err = dataRc.Close(); err != nil {
+				log.Error("ServeBlobOrLFS: Close: %v", err)
+			}
+			closed = true
+			return common.ServeBlob(ctx, blob)
+		}
+		if httpcache.HandleGenericETagCache(ctx.Req, ctx.Resp, `"`+pointer.Oid+`"`) {
+			return nil
+		}
+		lfsDataRc, err := lfs.ReadMetaObject(meta.Pointer)
+		if err != nil {
+			return err
+		}
+		defer func() {
+			if err = lfsDataRc.Close(); err != nil {
+				log.Error("ServeBlobOrLFS: Close: %v", err)
+			}
+		}()
+		return common.ServeData(ctx, ctx.Repo.TreePath, meta.Size, lfsDataRc)
+	}
+	if err = dataRc.Close(); err != nil {
+		log.Error("ServeBlobOrLFS: Close: %v", err)
+	}
+	closed = true
+
+	return common.ServeBlob(ctx, blob)
+}
+
+// SingleDownload download a file by repos path
+func SingleDownload(ctx *context.Context) {
+	blob, err := ctx.Repo.Commit.GetBlobByPath(ctx.Repo.TreePath)
+	if err != nil {
+		if git.IsErrNotExist(err) {
+			ctx.NotFound("GetBlobByPath", nil)
+		} else {
+			ctx.ServerError("GetBlobByPath", err)
+		}
+		return
+	}
+	if err = common.ServeBlob(ctx, blob); err != nil {
+		ctx.ServerError("ServeBlob", err)
+	}
+}
+
+// SingleDownloadOrLFS download a file by repos path redirecting to LFS if necessary
+func SingleDownloadOrLFS(ctx *context.Context) {
+	blob, err := ctx.Repo.Commit.GetBlobByPath(ctx.Repo.TreePath)
+	if err != nil {
+		if git.IsErrNotExist(err) {
+			ctx.NotFound("GetBlobByPath", nil)
+		} else {
+			ctx.ServerError("GetBlobByPath", err)
+		}
+		return
+	}
+	if err = ServeBlobOrLFS(ctx, blob); err != nil {
+		ctx.ServerError("ServeBlobOrLFS", err)
+	}
+}
+
+// DownloadByID download a file by sha1 ID
+func DownloadByID(ctx *context.Context) {
+	blob, err := ctx.Repo.GitRepo.GetBlob(ctx.Params("sha"))
+	if err != nil {
+		if git.IsErrNotExist(err) {
+			ctx.NotFound("GetBlob", nil)
+		} else {
+			ctx.ServerError("GetBlob", err)
+		}
+		return
+	}
+	if err = common.ServeBlob(ctx, blob); err != nil {
+		ctx.ServerError("ServeBlob", err)
+	}
+}
+
+// DownloadByIDOrLFS download a file by sha1 ID taking account of LFS
+func DownloadByIDOrLFS(ctx *context.Context) {
+	blob, err := ctx.Repo.GitRepo.GetBlob(ctx.Params("sha"))
+	if err != nil {
+		if git.IsErrNotExist(err) {
+			ctx.NotFound("GetBlob", nil)
+		} else {
+			ctx.ServerError("GetBlob", err)
+		}
+		return
+	}
+	if err = ServeBlobOrLFS(ctx, blob); err != nil {
+		ctx.ServerError("ServeBlob", err)
+	}
+}