From 6ad834e236756e7ba3de27e59681080a7ec4fcf1 Mon Sep 17 00:00:00 2001
From: Mura Li <typeless@users.noreply.github.com>
Date: Wed, 23 Jan 2019 18:26:32 +0800
Subject: [PATCH] Optimize pulls merging (#4921)
* Optimize pulls merging
By utilizing `git clone -s --no-checkout` rather than cloning the whole
repo.
* Use sparse-checkout to speedup pulls merge
* Use bytes.Buffer instead of strings.Builder for backward compatibility
* Fix empty diff-tree output for repos with only the initial commit
* Fix missing argument for the format string
* Rework diff-tree-list generation
* Remove logging code
* File list for sparse-checkout must be prefix with /
Otherwise, they would match all files with the same name under
subdirectories.
* Update onto the rebased head
* Use referecen repo to avoid fetching objects
---
models/pull.go | 102 +++++++++++++++++++++++++++++++++++++++++--------
1 file changed, 86 insertions(+), 16 deletions(-)
diff --git a/models/pull.go b/models/pull.go
index 8b4961d8b6..e1a69ad2fc 100644
--- a/models/pull.go
+++ b/models/pull.go
@@ -5,6 +5,8 @@
package models
import (
+ "bufio"
+ "bytes"
"fmt"
"io/ioutil"
"os"
@@ -328,6 +330,34 @@ func (pr *PullRequest) CheckUserAllowedToMerge(doer *User) (err error) {
return nil
}
+func getDiffTree(repoPath, baseBranch, headBranch string) (string, error) {
+ getDiffTreeFromBranch := func(repoPath, baseBranch, headBranch string) (string, error) {
+ var stdout, stderr string
+ // Compute the diff-tree for sparse-checkout
+ // The branch argument must be enclosed with double-quotes ("") in case it contains slashes (e.g "feature/test")
+ stdout, stderr, err := process.GetManager().ExecDir(-1, repoPath,
+ fmt.Sprintf("PullRequest.Merge (git diff-tree): %s", repoPath),
+ "git", "diff-tree", "--no-commit-id", "--name-only", "-r", "--root", baseBranch, headBranch)
+ if err != nil {
+ return "", fmt.Errorf("git diff-tree [%s base:%s head:%s]: %s", repoPath, baseBranch, headBranch, stderr)
+ }
+ return stdout, nil
+ }
+
+ list, err := getDiffTreeFromBranch(repoPath, baseBranch, headBranch)
+ if err != nil {
+ return "", err
+ }
+
+ // Prefixing '/' for each entry, otherwise all files with the same name in subdirectories would be matched.
+ out := bytes.Buffer{}
+ scanner := bufio.NewScanner(strings.NewReader(list))
+ for scanner.Scan() {
+ fmt.Fprintf(&out, "/%s\n", scanner.Text())
+ }
+ return out.String(), nil
+}
+
// Merge merges pull request to base repository.
// FIXME: add repoWorkingPull make sure two merges does not happen at same time.
func (pr *PullRequest) Merge(doer *User, baseGitRepo *git.Repository, mergeStyle MergeStyle, message string) (err error) {
@@ -371,36 +401,76 @@ func (pr *PullRequest) Merge(doer *User, baseGitRepo *git.Repository, mergeStyle
var stderr string
if _, stderr, err = process.GetManager().ExecTimeout(5*time.Minute,
fmt.Sprintf("PullRequest.Merge (git clone): %s", tmpBasePath),
- "git", "clone", baseGitRepo.Path, tmpBasePath); err != nil {
+ "git", "clone", "-s", "--no-checkout", "-b", pr.BaseBranch, baseGitRepo.Path, tmpBasePath); err != nil {
return fmt.Errorf("git clone: %s", stderr)
}
- // Check out base branch.
- if _, stderr, err = process.GetManager().ExecDir(-1, tmpBasePath,
- fmt.Sprintf("PullRequest.Merge (git checkout): %s", tmpBasePath),
- "git", "checkout", pr.BaseBranch); err != nil {
- return fmt.Errorf("git checkout: %s", stderr)
- }
+ remoteRepoName := "head_repo"
// Add head repo remote.
+ addCacheRepo := func(staging, cache string) error {
+ p := filepath.Join(staging, ".git", "objects", "info", "alternates")
+ f, err := os.OpenFile(p, os.O_APPEND|os.O_WRONLY, 0600)
+ if err != nil {
+ return err
+ }
+ defer f.Close()
+ data := filepath.Join(cache, "objects")
+ if _, err := fmt.Fprintln(f, data); err != nil {
+ return err
+ }
+ return nil
+ }
+
+ if err := addCacheRepo(tmpBasePath, headRepoPath); err != nil {
+ return fmt.Errorf("addCacheRepo [%s -> %s]: %v", headRepoPath, tmpBasePath, err)
+ }
if _, stderr, err = process.GetManager().ExecDir(-1, tmpBasePath,
fmt.Sprintf("PullRequest.Merge (git remote add): %s", tmpBasePath),
- "git", "remote", "add", "head_repo", headRepoPath); err != nil {
+ "git", "remote", "add", remoteRepoName, headRepoPath); err != nil {
return fmt.Errorf("git remote add [%s -> %s]: %s", headRepoPath, tmpBasePath, stderr)
}
- // Merge commits.
+ // Fetch head branch
if _, stderr, err = process.GetManager().ExecDir(-1, tmpBasePath,
fmt.Sprintf("PullRequest.Merge (git fetch): %s", tmpBasePath),
- "git", "fetch", "head_repo"); err != nil {
+ "git", "fetch", remoteRepoName); err != nil {
return fmt.Errorf("git fetch [%s -> %s]: %s", headRepoPath, tmpBasePath, stderr)
}
+ trackingBranch := path.Join(remoteRepoName, pr.HeadBranch)
+ stagingBranch := fmt.Sprintf("%s_%s", remoteRepoName, pr.HeadBranch)
+
+ // Enable sparse-checkout
+ sparseCheckoutList, err := getDiffTree(tmpBasePath, pr.BaseBranch, trackingBranch)
+ if err != nil {
+ return fmt.Errorf("getDiffTree: %v", err)
+ }
+
+ sparseCheckoutListPath := filepath.Join(tmpBasePath, ".git", "info", "sparse-checkout")
+ if err := ioutil.WriteFile(sparseCheckoutListPath, []byte(sparseCheckoutList), 0600); err != nil {
+ return fmt.Errorf("Writing sparse-checkout file to %s: %v", sparseCheckoutListPath, err)
+ }
+
+ if _, stderr, err = process.GetManager().ExecDir(-1, tmpBasePath,
+ fmt.Sprintf("PullRequest.Merge (git config): %s", tmpBasePath),
+ "git", "config", "--local", "core.sparseCheckout", "true"); err != nil {
+ return fmt.Errorf("git config [core.sparsecheckout -> true]: %v", stderr)
+ }
+
+ // Read base branch index
+ if _, stderr, err = process.GetManager().ExecDir(-1, tmpBasePath,
+ fmt.Sprintf("PullRequest.Merge (git read-tree): %s", tmpBasePath),
+ "git", "read-tree", "HEAD"); err != nil {
+ return fmt.Errorf("git read-tree HEAD: %s", stderr)
+ }
+
+ // Merge commits.
switch mergeStyle {
case MergeStyleMerge:
if _, stderr, err = process.GetManager().ExecDir(-1, tmpBasePath,
fmt.Sprintf("PullRequest.Merge (git merge --no-ff --no-commit): %s", tmpBasePath),
- "git", "merge", "--no-ff", "--no-commit", "head_repo/"+pr.HeadBranch); err != nil {
+ "git", "merge", "--no-ff", "--no-commit", trackingBranch); err != nil {
return fmt.Errorf("git merge --no-ff --no-commit [%s]: %v - %s", tmpBasePath, err, stderr)
}
@@ -415,7 +485,7 @@ func (pr *PullRequest) Merge(doer *User, baseGitRepo *git.Repository, mergeStyle
// Checkout head branch
if _, stderr, err = process.GetManager().ExecDir(-1, tmpBasePath,
fmt.Sprintf("PullRequest.Merge (git checkout): %s", tmpBasePath),
- "git", "checkout", "-b", "head_repo_"+pr.HeadBranch, "head_repo/"+pr.HeadBranch); err != nil {
+ "git", "checkout", "-b", stagingBranch, trackingBranch); err != nil {
return fmt.Errorf("git checkout: %s", stderr)
}
// Rebase before merging
@@ -433,14 +503,14 @@ func (pr *PullRequest) Merge(doer *User, baseGitRepo *git.Repository, mergeStyle
// Merge fast forward
if _, stderr, err = process.GetManager().ExecDir(-1, tmpBasePath,
fmt.Sprintf("PullRequest.Merge (git rebase): %s", tmpBasePath),
- "git", "merge", "--ff-only", "-q", "head_repo_"+pr.HeadBranch); err != nil {
+ "git", "merge", "--ff-only", "-q", stagingBranch); err != nil {
return fmt.Errorf("git merge --ff-only [%s -> %s]: %s", headRepoPath, tmpBasePath, stderr)
}
case MergeStyleRebaseMerge:
// Checkout head branch
if _, stderr, err = process.GetManager().ExecDir(-1, tmpBasePath,
fmt.Sprintf("PullRequest.Merge (git checkout): %s", tmpBasePath),
- "git", "checkout", "-b", "head_repo_"+pr.HeadBranch, "head_repo/"+pr.HeadBranch); err != nil {
+ "git", "checkout", "-b", stagingBranch, trackingBranch); err != nil {
return fmt.Errorf("git checkout: %s", stderr)
}
// Rebase before merging
@@ -458,7 +528,7 @@ func (pr *PullRequest) Merge(doer *User, baseGitRepo *git.Repository, mergeStyle
// Prepare merge with commit
if _, stderr, err = process.GetManager().ExecDir(-1, tmpBasePath,
fmt.Sprintf("PullRequest.Merge (git merge): %s", tmpBasePath),
- "git", "merge", "--no-ff", "--no-commit", "-q", "head_repo_"+pr.HeadBranch); err != nil {
+ "git", "merge", "--no-ff", "--no-commit", "-q", stagingBranch); err != nil {
return fmt.Errorf("git merge --no-ff [%s -> %s]: %s", headRepoPath, tmpBasePath, stderr)
}
@@ -475,7 +545,7 @@ func (pr *PullRequest) Merge(doer *User, baseGitRepo *git.Repository, mergeStyle
// Merge with squash
if _, stderr, err = process.GetManager().ExecDir(-1, tmpBasePath,
fmt.Sprintf("PullRequest.Merge (git squash): %s", tmpBasePath),
- "git", "merge", "-q", "--squash", "head_repo/"+pr.HeadBranch); err != nil {
+ "git", "merge", "-q", "--squash", trackingBranch); err != nil {
return fmt.Errorf("git merge --squash [%s -> %s]: %s", headRepoPath, tmpBasePath, stderr)
}
sig := pr.Issue.Poster.NewGitSig()