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>

5 files changed, 862 insertions, 0 deletions

diff --git a/modules/uploader/delete.go b/modules/uploader/delete.go
new file mode 100644
index 0000000000..fbe451c5d0
--- /dev/null
+++ b/modules/uploader/delete.go
@@ -0,0 +1,100 @@
+// Copyright 2019 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 uploader
+
+import (
+	"fmt"
+
+	"code.gitea.io/git"
+	"code.gitea.io/gitea/models"
+)
+
+// DeleteRepoFileOptions holds the repository delete file options
+type DeleteRepoFileOptions struct {
+	LastCommitID string
+	OldBranch    string
+	NewBranch    string
+	TreePath     string
+	Message      string
+}
+
+// DeleteRepoFile deletes a file in the given repository
+func DeleteRepoFile(repo *models.Repository, doer *models.User, opts *DeleteRepoFileOptions) error {
+	t, err := NewTemporaryUploadRepository(repo)
+	defer t.Close()
+	if err != nil {
+		return err
+	}
+	if err := t.Clone(opts.OldBranch); err != nil {
+		return err
+	}
+	if err := t.SetDefaultIndex(); err != nil {
+		return err
+	}
+
+	filesInIndex, err := t.LsFiles(opts.TreePath)
+	if err != nil {
+		return fmt.Errorf("UpdateRepoFile: %v", err)
+	}
+
+	inFilelist := false
+	for _, file := range filesInIndex {
+		if file == opts.TreePath {
+			inFilelist = true
+		}
+	}
+	if !inFilelist {
+		return git.ErrNotExist{RelPath: opts.TreePath}
+	}
+
+	if err := t.RemoveFilesFromIndex(opts.TreePath); err != nil {
+		return err
+	}
+
+	// Now write the tree
+	treeHash, err := t.WriteTree()
+	if err != nil {
+		return err
+	}
+
+	// Now commit the tree
+	commitHash, err := t.CommitTree(doer, treeHash, opts.Message)
+	if err != nil {
+		return err
+	}
+
+	// Then push this tree to NewBranch
+	if err := t.Push(doer, commitHash, opts.NewBranch); err != nil {
+		return err
+	}
+
+	// Simulate push event.
+	oldCommitID := opts.LastCommitID
+	if opts.NewBranch != opts.OldBranch {
+		oldCommitID = git.EmptySHA
+	}
+
+	if err = repo.GetOwner(); err != nil {
+		return fmt.Errorf("GetOwner: %v", err)
+	}
+	err = models.PushUpdate(
+		opts.NewBranch,
+		models.PushUpdateOptions{
+			PusherID:     doer.ID,
+			PusherName:   doer.Name,
+			RepoUserName: repo.Owner.Name,
+			RepoName:     repo.Name,
+			RefFullName:  git.BranchPrefix + opts.NewBranch,
+			OldCommitID:  oldCommitID,
+			NewCommitID:  commitHash,
+		},
+	)
+	if err != nil {
+		return fmt.Errorf("PushUpdate: %v", err)
+	}
+
+	// FIXME: Should we UpdateRepoIndexer(repo) here?
+	return nil
+}
diff --git a/modules/uploader/diff.go b/modules/uploader/diff.go
new file mode 100644
index 0000000000..e01947ea61
--- /dev/null
+++ b/modules/uploader/diff.go
@@ -0,0 +1,38 @@
+// Copyright 2019 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 uploader
+
+import (
+	"strings"
+
+	"code.gitea.io/gitea/models"
+)
+
+// GetDiffPreview produces and returns diff result of a file which is not yet committed.
+func GetDiffPreview(repo *models.Repository, branch, treePath, content string) (*models.Diff, error) {
+	t, err := NewTemporaryUploadRepository(repo)
+	defer t.Close()
+	if err != nil {
+		return nil, err
+	}
+	if err := t.Clone(branch); err != nil {
+		return nil, err
+	}
+	if err := t.SetDefaultIndex(); err != nil {
+		return nil, err
+	}
+
+	// Add the object to the database
+	objectHash, err := t.HashObject(strings.NewReader(content))
+	if err != nil {
+		return nil, err
+	}
+
+	// Add the object to the index
+	if err := t.AddObjectToIndex("100644", objectHash, treePath); err != nil {
+		return nil, err
+	}
+	return t.DiffIndex()
+}
diff --git a/modules/uploader/repo.go b/modules/uploader/repo.go
new file mode 100644
index 0000000000..33cc160ca9
--- /dev/null
+++ b/modules/uploader/repo.go
@@ -0,0 +1,359 @@
+// Copyright 2019 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 uploader
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"io"
+	"os"
+	"os/exec"
+	"path"
+	"strings"
+	"time"
+
+	"code.gitea.io/gitea/models"
+	"code.gitea.io/gitea/modules/process"
+	"code.gitea.io/gitea/modules/setting"
+
+	"github.com/Unknwon/com"
+)
+
+// TemporaryUploadRepository is a type to wrap our upload repositories
+type TemporaryUploadRepository struct {
+	repo     *models.Repository
+	basePath string
+}
+
+// NewTemporaryUploadRepository creates a new temporary upload repository
+func NewTemporaryUploadRepository(repo *models.Repository) (*TemporaryUploadRepository, error) {
+	timeStr := com.ToStr(time.Now().Nanosecond()) // SHOULD USE SOMETHING UNIQUE
+	basePath := path.Join(models.LocalCopyPath(), "upload-"+timeStr+".git")
+	if err := os.MkdirAll(path.Dir(basePath), os.ModePerm); err != nil {
+		return nil, fmt.Errorf("Failed to create dir %s: %v", basePath, err)
+	}
+	t := &TemporaryUploadRepository{repo: repo, basePath: basePath}
+	return t, nil
+}
+
+// Close the repository cleaning up all files
+func (t *TemporaryUploadRepository) Close() {
+	if _, err := os.Stat(t.basePath); !os.IsNotExist(err) {
+		os.RemoveAll(t.basePath)
+	}
+}
+
+// Clone the base repository to our path and set branch as the HEAD
+func (t *TemporaryUploadRepository) Clone(branch string) error {
+	if _, stderr, err := process.GetManager().ExecTimeout(5*time.Minute,
+		fmt.Sprintf("Clone (git clone -s --bare): %s", t.basePath),
+		"git", "clone", "-s", "--bare", "-b", branch, t.repo.RepoPath(), t.basePath); err != nil {
+		return fmt.Errorf("Clone: %v %s", err, stderr)
+	}
+	return nil
+}
+
+// SetDefaultIndex sets the git index to our HEAD
+func (t *TemporaryUploadRepository) SetDefaultIndex() error {
+	if _, stderr, err := process.GetManager().ExecDir(5*time.Minute,
+		t.basePath,
+		fmt.Sprintf("SetDefaultIndex (git read-tree HEAD): %s", t.basePath),
+		"git", "read-tree", "HEAD"); err != nil {
+		return fmt.Errorf("SetDefaultIndex: %v %s", err, stderr)
+	}
+	return nil
+}
+
+// LsFiles checks if the given filename arguments are in the index
+func (t *TemporaryUploadRepository) LsFiles(filenames ...string) ([]string, error) {
+	stdOut := new(bytes.Buffer)
+	stdErr := new(bytes.Buffer)
+
+	timeout := 5 * time.Minute
+	ctx, cancel := context.WithTimeout(context.Background(), timeout)
+	defer cancel()
+
+	cmdArgs := []string{"ls-files", "-z", "--"}
+	for _, arg := range filenames {
+		if arg != "" {
+			cmdArgs = append(cmdArgs, arg)
+		}
+	}
+
+	cmd := exec.CommandContext(ctx, "git", cmdArgs...)
+	desc := fmt.Sprintf("lsFiles: (git ls-files) %v", cmdArgs)
+	cmd.Dir = t.basePath
+	cmd.Stdout = stdOut
+	cmd.Stderr = stdErr
+
+	if err := cmd.Start(); err != nil {
+		return nil, fmt.Errorf("exec(%s) failed: %v(%v)", desc, err, ctx.Err())
+	}
+
+	pid := process.GetManager().Add(desc, cmd)
+	err := cmd.Wait()
+	process.GetManager().Remove(pid)
+
+	if err != nil {
+		err = fmt.Errorf("exec(%d:%s) failed: %v(%v) stdout: %v stderr: %v", pid, desc, err, ctx.Err(), stdOut, stdErr)
+		return nil, err
+	}
+
+	filelist := make([]string, len(filenames))
+	for _, line := range bytes.Split(stdOut.Bytes(), []byte{'\000'}) {
+		filelist = append(filelist, string(line))
+	}
+
+	return filelist, err
+}
+
+// RemoveFilesFromIndex removes the given files from the index
+func (t *TemporaryUploadRepository) RemoveFilesFromIndex(filenames ...string) error {
+	stdOut := new(bytes.Buffer)
+	stdErr := new(bytes.Buffer)
+	stdIn := new(bytes.Buffer)
+	for _, file := range filenames {
+		if file != "" {
+			stdIn.WriteString("0 0000000000000000000000000000000000000000\t")
+			stdIn.WriteString(file)
+			stdIn.WriteByte('\000')
+		}
+	}
+
+	timeout := 5 * time.Minute
+	ctx, cancel := context.WithTimeout(context.Background(), timeout)
+	defer cancel()
+
+	cmdArgs := []string{"update-index", "--remove", "-z", "--index-info"}
+	cmd := exec.CommandContext(ctx, "git", cmdArgs...)
+	desc := fmt.Sprintf("removeFilesFromIndex: (git update-index) %v", filenames)
+	cmd.Dir = t.basePath
+	cmd.Stdout = stdOut
+	cmd.Stderr = stdErr
+	cmd.Stdin = bytes.NewReader(stdIn.Bytes())
+
+	if err := cmd.Start(); err != nil {
+		return fmt.Errorf("exec(%s) failed: %v(%v)", desc, err, ctx.Err())
+	}
+
+	pid := process.GetManager().Add(desc, cmd)
+	err := cmd.Wait()
+	process.GetManager().Remove(pid)
+
+	if err != nil {
+		err = fmt.Errorf("exec(%d:%s) failed: %v(%v) stdout: %v stderr: %v", pid, desc, err, ctx.Err(), stdOut, stdErr)
+	}
+
+	return err
+}
+
+// HashObject writes the provided content to the object db and returns its hash
+func (t *TemporaryUploadRepository) HashObject(content io.Reader) (string, error) {
+	timeout := 5 * time.Minute
+	ctx, cancel := context.WithTimeout(context.Background(), timeout)
+	defer cancel()
+
+	hashCmd := exec.CommandContext(ctx, "git", "hash-object", "-w", "--stdin")
+	hashCmd.Dir = t.basePath
+	hashCmd.Stdin = content
+	stdOutBuffer := new(bytes.Buffer)
+	stdErrBuffer := new(bytes.Buffer)
+	hashCmd.Stdout = stdOutBuffer
+	hashCmd.Stderr = stdErrBuffer
+	desc := fmt.Sprintf("hashObject: (git hash-object)")
+	if err := hashCmd.Start(); err != nil {
+		return "", fmt.Errorf("git hash-object: %s", err)
+	}
+
+	pid := process.GetManager().Add(desc, hashCmd)
+	err := hashCmd.Wait()
+	process.GetManager().Remove(pid)
+
+	if err != nil {
+		err = fmt.Errorf("exec(%d:%s) failed: %v(%v) stdout: %v stderr: %v", pid, desc, err, ctx.Err(), stdOutBuffer, stdErrBuffer)
+		return "", err
+	}
+
+	return strings.TrimSpace(stdOutBuffer.String()), nil
+}
+
+// AddObjectToIndex adds the provided object hash to the index with the provided mode and path
+func (t *TemporaryUploadRepository) AddObjectToIndex(mode, objectHash, objectPath string) error {
+	if _, stderr, err := process.GetManager().ExecDir(5*time.Minute,
+		t.basePath,
+		fmt.Sprintf("addObjectToIndex (git update-index): %s", t.basePath),
+		"git", "update-index", "--add", "--replace", "--cacheinfo", mode, objectHash, objectPath); err != nil {
+		return fmt.Errorf("git update-index: %s", stderr)
+	}
+	return nil
+}
+
+// WriteTree writes the current index as a tree to the object db and returns its hash
+func (t *TemporaryUploadRepository) WriteTree() (string, error) {
+	treeHash, stderr, err := process.GetManager().ExecDir(5*time.Minute,
+		t.basePath,
+		fmt.Sprintf("WriteTree (git write-tree): %s", t.basePath),
+		"git", "write-tree")
+	if err != nil {
+		return "", fmt.Errorf("git write-tree: %s", stderr)
+	}
+	return strings.TrimSpace(treeHash), nil
+
+}
+
+// CommitTree creates a commit from a given tree for the user with provided message
+func (t *TemporaryUploadRepository) CommitTree(doer *models.User, treeHash string, message string) (string, error) {
+	commitTimeStr := time.Now().Format(time.UnixDate)
+	sig := doer.NewGitSig()
+
+	// FIXME: Should we add SSH_ORIGINAL_COMMAND to this
+	// Because this may call hooks we should pass in the environment
+	env := append(os.Environ(),
+		"GIT_AUTHOR_NAME="+sig.Name,
+		"GIT_AUTHOR_EMAIL="+sig.Email,
+		"GIT_AUTHOR_DATE="+commitTimeStr,
+		"GIT_COMMITTER_NAME="+sig.Name,
+		"GIT_COMMITTER_EMAIL="+sig.Email,
+		"GIT_COMMITTER_DATE="+commitTimeStr,
+	)
+	commitHash, stderr, err := process.GetManager().ExecDirEnv(5*time.Minute,
+		t.basePath,
+		fmt.Sprintf("commitTree (git commit-tree): %s", t.basePath),
+		env,
+		"git", "commit-tree", treeHash, "-p", "HEAD", "-m", message)
+	if err != nil {
+		return "", fmt.Errorf("git commit-tree: %s", stderr)
+	}
+	return strings.TrimSpace(commitHash), nil
+}
+
+// Push the provided commitHash to the repository branch by the provided user
+func (t *TemporaryUploadRepository) Push(doer *models.User, commitHash string, branch string) error {
+	isWiki := "false"
+	if strings.HasSuffix(t.repo.Name, ".wiki") {
+		isWiki = "true"
+	}
+
+	sig := doer.NewGitSig()
+
+	// FIXME: Should we add SSH_ORIGINAL_COMMAND to this
+	// Because calls hooks we need to pass in the environment
+	env := append(os.Environ(),
+		"GIT_AUTHOR_NAME="+sig.Name,
+		"GIT_AUTHOR_EMAIL="+sig.Email,
+		"GIT_COMMITTER_NAME="+sig.Name,
+		"GIT_COMMITTER_EMAIL="+sig.Email,
+		models.EnvRepoName+"="+t.repo.Name,
+		models.EnvRepoUsername+"="+t.repo.OwnerName,
+		models.EnvRepoIsWiki+"="+isWiki,
+		models.EnvPusherName+"="+doer.Name,
+		models.EnvPusherID+"="+fmt.Sprintf("%d", doer.ID),
+		models.ProtectedBranchRepoID+"="+fmt.Sprintf("%d", t.repo.ID),
+	)
+
+	if _, stderr, err := process.GetManager().ExecDirEnv(5*time.Minute,
+		t.basePath,
+		fmt.Sprintf("actuallyPush (git push): %s", t.basePath),
+		env,
+		"git", "push", t.repo.RepoPath(), strings.TrimSpace(commitHash)+":refs/heads/"+strings.TrimSpace(branch)); err != nil {
+		return fmt.Errorf("git push: %s", stderr)
+	}
+	return nil
+}
+
+// DiffIndex returns a Diff of the current index to the head
+func (t *TemporaryUploadRepository) DiffIndex() (diff *models.Diff, err error) {
+	timeout := 5 * time.Minute
+	ctx, cancel := context.WithTimeout(context.Background(), timeout)
+	defer cancel()
+
+	stdErr := new(bytes.Buffer)
+
+	cmd := exec.CommandContext(ctx, "git", "diff-index", "--cached", "-p", "HEAD")
+	cmd.Dir = t.basePath
+	cmd.Stderr = stdErr
+
+	stdout, err := cmd.StdoutPipe()
+	if err != nil {
+		return nil, fmt.Errorf("StdoutPipe: %v stderr %s", err, stdErr.String())
+	}
+
+	if err = cmd.Start(); err != nil {
+		return nil, fmt.Errorf("Start: %v stderr %s", err, stdErr.String())
+	}
+
+	pid := process.GetManager().Add(fmt.Sprintf("diffIndex [repo_path: %s]", t.repo.RepoPath()), cmd)
+	defer process.GetManager().Remove(pid)
+
+	diff, err = models.ParsePatch(setting.Git.MaxGitDiffLines, setting.Git.MaxGitDiffLineCharacters, setting.Git.MaxGitDiffFiles, stdout)
+	if err != nil {
+		return nil, fmt.Errorf("ParsePatch: %v", err)
+	}
+
+	if err = cmd.Wait(); err != nil {
+		return nil, fmt.Errorf("Wait: %v", err)
+	}
+
+	return diff, nil
+}
+
+// CheckAttribute checks the given attribute of the provided files
+func (t *TemporaryUploadRepository) CheckAttribute(attribute string, args ...string) (map[string]map[string]string, error) {
+	stdOut := new(bytes.Buffer)
+	stdErr := new(bytes.Buffer)
+
+	timeout := 5 * time.Minute
+	ctx, cancel := context.WithTimeout(context.Background(), timeout)
+	defer cancel()
+
+	cmdArgs := []string{"check-attr", "-z", attribute, "--cached", "--"}
+	for _, arg := range args {
+		if arg != "" {
+			cmdArgs = append(cmdArgs, arg)
+		}
+	}
+
+	cmd := exec.CommandContext(ctx, "git", cmdArgs...)
+	desc := fmt.Sprintf("checkAttr: (git check-attr) %s %v", attribute, cmdArgs)
+	cmd.Dir = t.basePath
+	cmd.Stdout = stdOut
+	cmd.Stderr = stdErr
+
+	if err := cmd.Start(); err != nil {
+		return nil, fmt.Errorf("exec(%s) failed: %v(%v)", desc, err, ctx.Err())
+	}
+
+	pid := process.GetManager().Add(desc, cmd)
+	err := cmd.Wait()
+	process.GetManager().Remove(pid)
+
+	if err != nil {
+		err = fmt.Errorf("exec(%d:%s) failed: %v(%v) stdout: %v stderr: %v", pid, desc, err, ctx.Err(), stdOut, stdErr)
+		return nil, err
+	}
+
+	fields := bytes.Split(stdOut.Bytes(), []byte{'\000'})
+
+	if len(fields)%3 != 1 {
+		return nil, fmt.Errorf("Wrong number of fields in return from check-attr")
+	}
+
+	var name2attribute2info = make(map[string]map[string]string)
+
+	for i := 0; i < (len(fields) / 3); i++ {
+		filename := string(fields[3*i])
+		attribute := string(fields[3*i+1])
+		info := string(fields[3*i+2])
+		attribute2info := name2attribute2info[filename]
+		if attribute2info == nil {
+			attribute2info = make(map[string]string)
+		}
+		attribute2info[attribute] = info
+		name2attribute2info[filename] = attribute2info
+	}
+
+	return name2attribute2info, err
+}
diff --git a/modules/uploader/update.go b/modules/uploader/update.go
new file mode 100644
index 0000000000..08caf11ee1
--- /dev/null
+++ b/modules/uploader/update.go
@@ -0,0 +1,159 @@
+// Copyright 2019 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 uploader
+
+import (
+	"fmt"
+	"strings"
+
+	"code.gitea.io/git"
+	"code.gitea.io/gitea/models"
+	"code.gitea.io/gitea/modules/lfs"
+	"code.gitea.io/gitea/modules/setting"
+)
+
+// UpdateRepoFileOptions holds the repository file update options
+type UpdateRepoFileOptions struct {
+	LastCommitID string
+	OldBranch    string
+	NewBranch    string
+	OldTreeName  string
+	NewTreeName  string
+	Message      string
+	Content      string
+	IsNewFile    bool
+}
+
+// UpdateRepoFile adds or updates a file in the given repository
+func UpdateRepoFile(repo *models.Repository, doer *models.User, opts *UpdateRepoFileOptions) error {
+	t, err := NewTemporaryUploadRepository(repo)
+	defer t.Close()
+	if err != nil {
+		return err
+	}
+	if err := t.Clone(opts.OldBranch); err != nil {
+		return err
+	}
+	if err := t.SetDefaultIndex(); err != nil {
+		return err
+	}
+
+	filesInIndex, err := t.LsFiles(opts.NewTreeName, opts.OldTreeName)
+	if err != nil {
+		return fmt.Errorf("UpdateRepoFile: %v", err)
+	}
+
+	if opts.IsNewFile {
+		for _, file := range filesInIndex {
+			if file == opts.NewTreeName {
+				return models.ErrRepoFileAlreadyExist{FileName: opts.NewTreeName}
+			}
+		}
+	}
+
+	//var stdout string
+	if opts.OldTreeName != opts.NewTreeName && len(filesInIndex) > 0 {
+		for _, file := range filesInIndex {
+			if file == opts.OldTreeName {
+				if err := t.RemoveFilesFromIndex(opts.OldTreeName); err != nil {
+					return err
+				}
+			}
+		}
+
+	}
+
+	// Check there is no way this can return multiple infos
+	filename2attribute2info, err := t.CheckAttribute("filter", opts.NewTreeName)
+	if err != nil {
+		return err
+	}
+
+	content := opts.Content
+	var lfsMetaObject *models.LFSMetaObject
+
+	if filename2attribute2info[opts.NewTreeName] != nil && filename2attribute2info[opts.NewTreeName]["filter"] == "lfs" {
+		// OK so we are supposed to LFS this data!
+		oid, err := models.GenerateLFSOid(strings.NewReader(opts.Content))
+		if err != nil {
+			return err
+		}
+		lfsMetaObject = &models.LFSMetaObject{Oid: oid, Size: int64(len(opts.Content)), RepositoryID: repo.ID}
+		content = lfsMetaObject.Pointer()
+	}
+
+	// Add the object to the database
+	objectHash, err := t.HashObject(strings.NewReader(content))
+	if err != nil {
+		return err
+	}
+
+	// Add the object to the index
+	if err := t.AddObjectToIndex("100644", objectHash, opts.NewTreeName); err != nil {
+		return err
+	}
+
+	// Now write the tree
+	treeHash, err := t.WriteTree()
+	if err != nil {
+		return err
+	}
+
+	// Now commit the tree
+	commitHash, err := t.CommitTree(doer, treeHash, opts.Message)
+	if err != nil {
+		return err
+	}
+
+	if lfsMetaObject != nil {
+		// We have an LFS object - create it
+		lfsMetaObject, err = models.NewLFSMetaObject(lfsMetaObject)
+		if err != nil {
+			return err
+		}
+		contentStore := &lfs.ContentStore{BasePath: setting.LFS.ContentPath}
+		if !contentStore.Exists(lfsMetaObject) {
+			if err := contentStore.Put(lfsMetaObject, strings.NewReader(opts.Content)); err != nil {
+				if err2 := repo.RemoveLFSMetaObjectByOid(lfsMetaObject.Oid); err2 != nil {
+					return fmt.Errorf("Error whilst removing failed inserted LFS object %s: %v (Prev Error: %v)", lfsMetaObject.Oid, err2, err)
+				}
+				return err
+			}
+		}
+	}
+
+	// Then push this tree to NewBranch
+	if err := t.Push(doer, commitHash, opts.NewBranch); err != nil {
+		return err
+	}
+
+	// Simulate push event.
+	oldCommitID := opts.LastCommitID
+	if opts.NewBranch != opts.OldBranch {
+		oldCommitID = git.EmptySHA
+	}
+
+	if err = repo.GetOwner(); err != nil {
+		return fmt.Errorf("GetOwner: %v", err)
+	}
+	err = models.PushUpdate(
+		opts.NewBranch,
+		models.PushUpdateOptions{
+			PusherID:     doer.ID,
+			PusherName:   doer.Name,
+			RepoUserName: repo.Owner.Name,
+			RepoName:     repo.Name,
+			RefFullName:  git.BranchPrefix + opts.NewBranch,
+			OldCommitID:  oldCommitID,
+			NewCommitID:  commitHash,
+		},
+	)
+	if err != nil {
+		return fmt.Errorf("PushUpdate: %v", err)
+	}
+	models.UpdateRepoIndexer(repo)
+
+	return nil
+}
diff --git a/modules/uploader/upload.go b/modules/uploader/upload.go
new file mode 100644
index 0000000000..bee3f1b9b1
--- /dev/null
+++ b/modules/uploader/upload.go
@@ -0,0 +1,206 @@
+// Copyright 2019 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 uploader
+
+import (
+	"fmt"
+	"os"
+	"path"
+	"strings"
+
+	"code.gitea.io/gitea/modules/lfs"
+	"code.gitea.io/gitea/modules/setting"
+
+	"code.gitea.io/git"
+	"code.gitea.io/gitea/models"
+)
+
+// UploadRepoFileOptions contains the uploaded repository file options
+type UploadRepoFileOptions struct {
+	LastCommitID string
+	OldBranch    string
+	NewBranch    string
+	TreePath     string
+	Message      string
+	Files        []string // In UUID format.
+}
+
+type uploadInfo struct {
+	upload        *models.Upload
+	lfsMetaObject *models.LFSMetaObject
+}
+
+func cleanUpAfterFailure(infos *[]uploadInfo, t *TemporaryUploadRepository, original error) error {
+	for _, info := range *infos {
+		if info.lfsMetaObject == nil {
+			continue
+		}
+		if !info.lfsMetaObject.Existing {
+			if err := t.repo.RemoveLFSMetaObjectByOid(info.lfsMetaObject.Oid); err != nil {
+				original = fmt.Errorf("%v, %v", original, err)
+			}
+		}
+	}
+	return original
+}
+
+// UploadRepoFiles uploads files to the given repository
+func UploadRepoFiles(repo *models.Repository, doer *models.User, opts *UploadRepoFileOptions) error {
+	if len(opts.Files) == 0 {
+		return nil
+	}
+
+	uploads, err := models.GetUploadsByUUIDs(opts.Files)
+	if err != nil {
+		return fmt.Errorf("GetUploadsByUUIDs [uuids: %v]: %v", opts.Files, err)
+	}
+
+	t, err := NewTemporaryUploadRepository(repo)
+	defer t.Close()
+	if err != nil {
+		return err
+	}
+	if err := t.Clone(opts.OldBranch); err != nil {
+		return err
+	}
+	if err := t.SetDefaultIndex(); err != nil {
+		return err
+	}
+
+	names := make([]string, len(uploads))
+	infos := make([]uploadInfo, len(uploads))
+	for i, upload := range uploads {
+		names[i] = upload.Name
+		infos[i] = uploadInfo{upload: upload}
+	}
+
+	filename2attribute2info, err := t.CheckAttribute("filter", names...)
+	if err != nil {
+		return err
+	}
+
+	// Copy uploaded files into repository.
+	for i, uploadInfo := range infos {
+		file, err := os.Open(uploadInfo.upload.LocalPath())
+		if err != nil {
+			return err
+		}
+		defer file.Close()
+
+		var objectHash string
+		if filename2attribute2info[uploadInfo.upload.Name] != nil && filename2attribute2info[uploadInfo.upload.Name]["filter"] == "lfs" {
+			// Handle LFS
+			// FIXME: Inefficient! this should probably happen in models.Upload
+			oid, err := models.GenerateLFSOid(file)
+			if err != nil {
+				return err
+			}
+			fileInfo, err := file.Stat()
+			if err != nil {
+				return err
+			}
+
+			uploadInfo.lfsMetaObject = &models.LFSMetaObject{Oid: oid, Size: fileInfo.Size(), RepositoryID: t.repo.ID}
+
+			if objectHash, err = t.HashObject(strings.NewReader(uploadInfo.lfsMetaObject.Pointer())); err != nil {
+				return err
+			}
+			infos[i] = uploadInfo
+
+		} else {
+			if objectHash, err = t.HashObject(file); err != nil {
+				return err
+			}
+		}
+
+		// Add the object to the index
+		if err := t.AddObjectToIndex("100644", objectHash, path.Join(opts.TreePath, uploadInfo.upload.Name)); err != nil {
+			return err
+
+		}
+	}
+
+	// Now write the tree
+	treeHash, err := t.WriteTree()
+	if err != nil {
+		return err
+	}
+
+	// Now commit the tree
+	commitHash, err := t.CommitTree(doer, treeHash, opts.Message)
+	if err != nil {
+		return err
+	}
+
+	// Now deal with LFS objects
+	for _, uploadInfo := range infos {
+		if uploadInfo.lfsMetaObject == nil {
+			continue
+		}
+		uploadInfo.lfsMetaObject, err = models.NewLFSMetaObject(uploadInfo.lfsMetaObject)
+		if err != nil {
+			// OK Now we need to cleanup
+			return cleanUpAfterFailure(&infos, t, err)
+		}
+		// Don't move the files yet - we need to ensure that
+		// everything can be inserted first
+	}
+
+	// OK now we can insert the data into the store - there's no way to clean up the store
+	// once it's in there, it's in there.
+	contentStore := &lfs.ContentStore{BasePath: setting.LFS.ContentPath}
+	for _, uploadInfo := range infos {
+		if uploadInfo.lfsMetaObject == nil {
+			continue
+		}
+		if !contentStore.Exists(uploadInfo.lfsMetaObject) {
+			file, err := os.Open(uploadInfo.upload.LocalPath())
+			if err != nil {
+				return cleanUpAfterFailure(&infos, t, err)
+			}
+			defer file.Close()
+			// FIXME: Put regenerates the hash and copies the file over.
+			// I guess this strictly ensures the soundness of the store but this is inefficient.
+			if err := contentStore.Put(uploadInfo.lfsMetaObject, file); err != nil {
+				// OK Now we need to cleanup
+				// Can't clean up the store, once uploaded there they're there.
+				return cleanUpAfterFailure(&infos, t, err)
+			}
+		}
+	}
+
+	// Then push this tree to NewBranch
+	if err := t.Push(doer, commitHash, opts.NewBranch); err != nil {
+		return err
+	}
+
+	// Simulate push event.
+	oldCommitID := opts.LastCommitID
+	if opts.NewBranch != opts.OldBranch {
+		oldCommitID = git.EmptySHA
+	}
+
+	if err = repo.GetOwner(); err != nil {
+		return fmt.Errorf("GetOwner: %v", err)
+	}
+	err = models.PushUpdate(
+		opts.NewBranch,
+		models.PushUpdateOptions{
+			PusherID:     doer.ID,
+			PusherName:   doer.Name,
+			RepoUserName: repo.Owner.Name,
+			RepoName:     repo.Name,
+			RefFullName:  git.BranchPrefix + opts.NewBranch,
+			OldCommitID:  oldCommitID,
+			NewCommitID:  commitHash,
+		},
+	)
+	if err != nil {
+		return fmt.Errorf("PushUpdate: %v", err)
+	}
+	// FIXME: Should we models.UpdateRepoIndexer(repo) here?
+
+	return models.DeleteUploads(uploads...)
+}