1 files changed, 92 insertions, 0 deletions
diff --git a/modules/repofiles/tree.go b/modules/repofiles/tree.go
new file mode 100644
index 0000000000..8766ed36d0
--- /dev/null
+++ b/modules/repofiles/tree.go
@@ -0,0 +1,92 @@
+// 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 repofiles
+
+import (
+	"fmt"
+
+	"code.gitea.io/gitea/models"
+	"code.gitea.io/gitea/modules/git"
+	"code.gitea.io/gitea/modules/setting"
+	api "code.gitea.io/sdk/gitea"
+)
+
+// GetTreeBySHA get the GitTreeResponse of a repository using a sha hash.
+func GetTreeBySHA(repo *models.Repository, sha string, page, perPage int, recursive bool) (*api.GitTreeResponse, error) {
+	gitRepo, err := git.OpenRepository(repo.RepoPath())
+	gitTree, err := gitRepo.GetTree(sha)
+	if err != nil || gitTree == nil {
+		return nil, models.ErrSHANotFound{
+			SHA: sha,
+		}
+	}
+	tree := new(api.GitTreeResponse)
+	tree.SHA = gitTree.ID.String()
+	tree.URL = repo.APIURL() + "/git/trees/" + tree.SHA
+	var entries git.Entries
+	if recursive {
+		entries, err = gitTree.ListEntriesRecursive()
+	} else {
+		entries, err = gitTree.ListEntries()
+	}
+	if err != nil {
+		return nil, err
+	}
+	apiURL := repo.APIURL()
+	apiURLLen := len(apiURL)
+
+	// 51 is len(sha1) + len("/git/blobs/"). 40 + 11.
+	blobURL := make([]byte, apiURLLen+51)
+	copy(blobURL[:], apiURL)
+	copy(blobURL[apiURLLen:], "/git/blobs/")
+
+	// 51 is len(sha1) + len("/git/trees/"). 40 + 11.
+	treeURL := make([]byte, apiURLLen+51)
+	copy(treeURL[:], apiURL)
+	copy(treeURL[apiURLLen:], "/git/trees/")
+
+	// 40 is the size of the sha1 hash in hexadecimal format.
+	copyPos := len(treeURL) - 40
+
+	if perPage <= 0 || perPage > setting.API.DefaultGitTreesPerPage {
+		perPage = setting.API.DefaultGitTreesPerPage
+	}
+	if page <= 0 {
+		page = 1
+	}
+	tree.Page = page
+	tree.TotalCount = len(entries)
+	rangeStart := perPage * (page - 1)
+	if rangeStart >= len(entries) {
+		return tree, nil
+	}
+	var rangeEnd int
+	if len(entries) > perPage {
+		tree.Truncated = true
+	}
+	if rangeStart+perPage < len(entries) {
+		rangeEnd = rangeStart + perPage
+	} else {
+		rangeEnd = len(entries)
+	}
+	tree.Entries = make([]api.GitEntry, rangeEnd-rangeStart)
+	for e := rangeStart; e < rangeEnd; e++ {
+		i := e - rangeStart
+		tree.Entries[i].Path = entries[e].Name()
+		tree.Entries[i].Mode = fmt.Sprintf("%06x", entries[e].Mode())
+		tree.Entries[i].Type = string(entries[e].Type)
+		tree.Entries[i].Size = entries[e].Size()
+		tree.Entries[i].SHA = entries[e].ID.String()
+
+		if entries[e].IsDir() {
+			copy(treeURL[copyPos:], entries[e].ID.String())
+			tree.Entries[i].URL = string(treeURL[:])
+		} else {
+			copy(blobURL[copyPos:], entries[e].ID.String())
+			tree.Entries[i].URL = string(blobURL[:])
+		}
+	}
+	return tree, nil
+}