api: add `GET /api/v1/{owner}/{repo}/commits` endpoint (#6574)

This pull request targets issue #6573.

It provides a new API endpoint: `/api/v1/repos/{org}/{repo}/commits?pageSize=<int>` with a default page size of 30 commits (the same as the UI).

This implementation currently only focuses on the main/master branch of the repository, and does not provide the ability to return commit history for other branches.

- Note: Since the logic for converting a git.Commit to api.Commit had to be used in `GetAllCommits` and `GetSingleCommit`, I decided to pull the code out into a helper function, ` gitCommitToAPICommit(commit, context)`.

internal/route/api/v1/api.go

@@ -286,6 +286,7 @@ func RegisterRoutes(m *macaron.Macaron) {
 				})
 				m.Group("/commits", func() {
 					m.Get("/:sha", repo.GetSingleCommit)
+					m.Get("", repo.GetAllCommits)
 					m.Get("/*", repo.GetReferenceSHA)
 				})
 

internal/route/api/v1/repo/commits.go

@@ -18,6 +18,40 @@ import (
 	"gogs.io/gogs/internal/gitutil"
 )
 
+// GetAllCommits returns a slice of commits starting from HEAD.
+func GetAllCommits(c *context.APIContext) {
+	// Get pagesize, set default if it is not specified.
+	pageSize := c.QueryInt("pageSize")
+	if pageSize == 0 {
+		pageSize = 30
+	}
+
+	gitRepo, err := git.Open(c.Repo.Repository.RepoPath())
+	if err != nil {
+		c.Error(err, "open repository")
+		return
+	}
+
+	// The response object returned as JSON
+	result := make([]*api.Commit, 0, pageSize)
+	commits, err := gitRepo.Log("HEAD", git.LogOptions{MaxCount: pageSize})
+	if err != nil {
+		c.Error(err, "git log")
+	}
+
+	for _, commit := range commits {
+		apiCommit, err := gitCommitToAPICommit(commit, c)
+		if err != nil {
+			c.Error(err, "convert git commit to api commit")
+			return
+		}
+		result = append(result, apiCommit)
+	}
+
+	c.JSONSuccess(result)
+}
+
+// GetSingleCommit will return a single Commit object based on the specified SHA.
 func GetSingleCommit(c *context.APIContext) {
 	if strings.Contains(c.Req.Header.Get("Accept"), api.MediaApplicationSHA) {
 		c.SetParams("*", c.Params(":sha"))
@@ -36,66 +70,11 @@ func GetSingleCommit(c *context.APIContext) {
 		return
 	}
 
-	// Retrieve author and committer information
-	var apiAuthor, apiCommitter *api.User
-	author, err := db.GetUserByEmail(commit.Author.Email)
-	if err != nil && !db.IsErrUserNotExist(err) {
-		c.Error(err, "get user by author email")
-		return
-	} else if err == nil {
-		apiAuthor = author.APIFormat()
+	apiCommit, err := gitCommitToAPICommit(commit, c)
+	if err != nil {
+		c.Error(err, "convert git commit to api commit")
 	}
-	// Save one query if the author is also the committer
-	if commit.Committer.Email == commit.Author.Email {
-		apiCommitter = apiAuthor
-	} else {
-		committer, err := db.GetUserByEmail(commit.Committer.Email)
-		if err != nil && !db.IsErrUserNotExist(err) {
-			c.Error(err, "get user by committer email")
-			return
-		} else if err == nil {
-			apiCommitter = committer.APIFormat()
-		}
-	}
-
-	// Retrieve parent(s) of the commit
-	apiParents := make([]*api.CommitMeta, commit.ParentsCount())
-	for i := 0; i < commit.ParentsCount(); i++ {
-		sha, _ := commit.ParentID(i)
-		apiParents[i] = &api.CommitMeta{
-			URL: c.BaseURL + "/repos/" + c.Repo.Repository.FullName() + "/commits/" + sha.String(),
-			SHA: sha.String(),
-		}
-	}
-
-	c.JSONSuccess(&api.Commit{
-		CommitMeta: &api.CommitMeta{
-			URL: conf.Server.ExternalURL + c.Link[1:],
-			SHA: commit.ID.String(),
-		},
-		HTMLURL: c.Repo.Repository.HTMLURL() + "/commits/" + commit.ID.String(),
-		RepoCommit: &api.RepoCommit{
-			URL: conf.Server.ExternalURL + c.Link[1:],
-			Author: &api.CommitUser{
-				Name:  commit.Author.Name,
-				Email: commit.Author.Email,
-				Date:  commit.Author.When.Format(time.RFC3339),
-			},
-			Committer: &api.CommitUser{
-				Name:  commit.Committer.Name,
-				Email: commit.Committer.Email,
-				Date:  commit.Committer.When.Format(time.RFC3339),
-			},
-			Message: commit.Summary(),
-			Tree: &api.CommitMeta{
-				URL: c.BaseURL + "/repos/" + c.Repo.Repository.FullName() + "/tree/" + commit.ID.String(),
-				SHA: commit.ID.String(),
-			},
-		},
-		Author:    apiAuthor,
-		Committer: apiCommitter,
-		Parents:   apiParents,
-	})
+	c.JSONSuccess(apiCommit)
 }
 
 func GetReferenceSHA(c *context.APIContext) {
@@ -136,3 +115,66 @@ func GetReferenceSHA(c *context.APIContext) {
 	}
 	c.PlainText(http.StatusOK, sha)
 }
+
+// gitCommitToApiCommit is a helper function to convert git commit object to API commit.
+func gitCommitToAPICommit(commit *git.Commit, c *context.APIContext) (*api.Commit, error) {
+	// Retrieve author and committer information
+	var apiAuthor, apiCommitter *api.User
+	author, err := db.GetUserByEmail(commit.Author.Email)
+	if err != nil && !db.IsErrUserNotExist(err) {
+		return nil, err
+	} else if err == nil {
+		apiAuthor = author.APIFormat()
+	}
+
+	// Save one query if the author is also the committer
+	if commit.Committer.Email == commit.Author.Email {
+		apiCommitter = apiAuthor
+	} else {
+		committer, err := db.GetUserByEmail(commit.Committer.Email)
+		if err != nil && !db.IsErrUserNotExist(err) {
+			return nil, err
+		} else if err == nil {
+			apiCommitter = committer.APIFormat()
+		}
+	}
+
+	// Retrieve parent(s) of the commit
+	apiParents := make([]*api.CommitMeta, commit.ParentsCount())
+	for i := 0; i < commit.ParentsCount(); i++ {
+		sha, _ := commit.ParentID(i)
+		apiParents[i] = &api.CommitMeta{
+			URL: c.BaseURL + "/repos/" + c.Repo.Repository.FullName() + "/commits/" + sha.String(),
+			SHA: sha.String(),
+		}
+	}
+
+	return &api.Commit{
+		CommitMeta: &api.CommitMeta{
+			URL: conf.Server.ExternalURL + c.Link[1:],
+			SHA: commit.ID.String(),
+		},
+		HTMLURL: c.Repo.Repository.HTMLURL() + "/commits/" + commit.ID.String(),
+		RepoCommit: &api.RepoCommit{
+			URL: conf.Server.ExternalURL + c.Link[1:],
+			Author: &api.CommitUser{
+				Name:  commit.Author.Name,
+				Email: commit.Author.Email,
+				Date:  commit.Author.When.Format(time.RFC3339),
+			},
+			Committer: &api.CommitUser{
+				Name:  commit.Committer.Name,
+				Email: commit.Committer.Email,
+				Date:  commit.Committer.When.Format(time.RFC3339),
+			},
+			Message: commit.Summary(),
+			Tree: &api.CommitMeta{
+				URL: c.BaseURL + "/repos/" + c.Repo.Repository.FullName() + "/tree/" + commit.ID.String(),
+				SHA: commit.ID.String(),
+			},
+		},
+		Author:    apiAuthor,
+		Committer: apiCommitter,
+		Parents:   apiParents,
+	}, nil
+}