Refactor editor upload, update and delete to use git plumbing and add…

… LFS support (#5702)

* Use git plumbing for upload: #5621 repo_editor.go: UploadRepoFile

* Use git plumbing for upload: #5621 repo_editor.go: GetDiffPreview

* Use git plumbing for upload: #5621 repo_editor.go: DeleteRepoFile

* Use git plumbing for upload: #5621 repo_editor.go: UploadRepoFiles

* Move branch checkout functions out of repo_editor.go as they are no longer used there

* BUGFIX: The default permissions should be 100644

    This is a change from the previous code but is more in keeping
    with the default behaviour of git.

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

* Standardise cleanUploadFilename to more closely match git

See verify_path in: https://github.com/git/git/blob/7f4e64169352e03476b0ea64e7e2973669e491a2/read-cache.c#L951

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

* Redirect on bad paths

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

* Refactor to move the uploading functions out to a module

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

* Add LFS support

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

* Update upload.go attribution header

Upload.go is essentially the remnants of repo_editor.go. The remaining code is essentially unchanged from the Gogs code, hence the Gogs attribution.

* Delete upload files after session committed

* Ensure that GIT_AUTHOR_NAME etc. are valid for git

see #5774

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

* Add in test cases per @lafriks comment

* Add space between gitea and github imports

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

* more examples in TestCleanUploadName

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

* fix formatting

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

* Set the SSH_ORIGINAL_COMMAND to ensure hooks are run

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

* Switch off SSH_ORIGINAL_COMMAND

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

models/lfs.go

@@ -1,7 +1,11 @@
 package models
 
 import (
+	"crypto/sha256"
+	"encoding/hex"
 	"errors"
+	"fmt"
+	"io"
 
 	"code.gitea.io/gitea/modules/util"
 )
@@ -16,6 +20,11 @@ type LFSMetaObject struct {
 	CreatedUnix  util.TimeStamp `xorm:"created"`
 }
 
+// Pointer returns the string representation of an LFS pointer file
+func (m *LFSMetaObject) Pointer() string {
+	return fmt.Sprintf("%s\n%s%s\nsize %d\n", LFSMetaFileIdentifier, LFSMetaFileOidPrefix, m.Oid, m.Size)
+}
+
 // LFSTokenResponse defines the JSON structure in which the JWT token is stored.
 // This structure is fetched via SSH and passed by the Git LFS client to the server
 // endpoint for authorization.
@@ -67,6 +76,16 @@ func NewLFSMetaObject(m *LFSMetaObject) (*LFSMetaObject, error) {
 	return m, sess.Commit()
 }
 
+// GenerateLFSOid generates a Sha256Sum to represent an oid for arbitrary content
+func GenerateLFSOid(content io.Reader) (string, error) {
+	h := sha256.New()
+	if _, err := io.Copy(h, content); err != nil {
+		return "", err
+	}
+	sum := h.Sum(nil)
+	return hex.EncodeToString(sum), nil
+}
+
 // GetLFSMetaObjectByOid selects a LFSMetaObject entry from database by its OID.
 // It may return ErrLFSObjectNotExist or a database error. If the error is nil,
 // the returned pointer is a valid LFSMetaObject.

models/repo_branch.go

@@ -14,6 +14,46 @@ import (
 	"github.com/Unknwon/com"
 )
 
+// discardLocalRepoBranchChanges discards local commits/changes of
+// given branch to make sure it is even to remote branch.
+func discardLocalRepoBranchChanges(localPath, branch string) error {
+	if !com.IsExist(localPath) {
+		return nil
+	}
+	// No need to check if nothing in the repository.
+	if !git.IsBranchExist(localPath, branch) {
+		return nil
+	}
+
+	refName := "origin/" + branch
+	if err := git.ResetHEAD(localPath, true, refName); err != nil {
+		return fmt.Errorf("git reset --hard %s: %v", refName, err)
+	}
+	return nil
+}
+
+// DiscardLocalRepoBranchChanges discards the local repository branch changes
+func (repo *Repository) DiscardLocalRepoBranchChanges(branch string) error {
+	return discardLocalRepoBranchChanges(repo.LocalCopyPath(), branch)
+}
+
+// checkoutNewBranch checks out to a new branch from the a branch name.
+func checkoutNewBranch(repoPath, localPath, oldBranch, newBranch string) error {
+	if err := git.Checkout(localPath, git.CheckoutOptions{
+		Timeout:   time.Duration(setting.Git.Timeout.Pull) * time.Second,
+		Branch:    newBranch,
+		OldBranch: oldBranch,
+	}); err != nil {
+		return fmt.Errorf("git checkout -b %s %s: %v", newBranch, oldBranch, err)
+	}
+	return nil
+}
+
+// CheckoutNewBranch checks out a new branch
+func (repo *Repository) CheckoutNewBranch(oldBranch, newBranch string) error {
+	return checkoutNewBranch(repo.RepoPath(), repo.LocalCopyPath(), oldBranch, newBranch)
+}
+
 // Branch holds the branch information
 type Branch struct {
 	Path string