1 files changed, 99 insertions, 0 deletions
diff --git a/routers/api/v1/utils/git.go b/routers/api/v1/utils/git.go
new file mode 100644
index 0000000..4e25137
--- /dev/null
+++ b/routers/api/v1/utils/git.go
@@ -0,0 +1,99 @@
+// Copyright 2021 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package utils
+
+import (
+	gocontext "context"
+	"fmt"
+	"net/http"
+
+	"code.gitea.io/gitea/modules/git"
+	"code.gitea.io/gitea/modules/gitrepo"
+	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/services/context"
+)
+
+// ResolveRefOrSha resolve ref to sha if exist
+func ResolveRefOrSha(ctx *context.APIContext, ref string) string {
+	if len(ref) == 0 {
+		ctx.Error(http.StatusBadRequest, "ref not given", nil)
+		return ""
+	}
+
+	sha := ref
+	// Search branches and tags
+	for _, refType := range []string{"heads", "tags"} {
+		refSHA, lastMethodName, err := searchRefCommitByType(ctx, refType, ref)
+		if err != nil {
+			ctx.Error(http.StatusInternalServerError, lastMethodName, err)
+			return ""
+		}
+		if refSHA != "" {
+			sha = refSHA
+			break
+		}
+	}
+
+	sha = MustConvertToSHA1(ctx, ctx.Repo, sha)
+
+	if ctx.Repo.GitRepo != nil {
+		err := ctx.Repo.GitRepo.AddLastCommitCache(ctx.Repo.Repository.GetCommitsCountCacheKey(ref, ref != sha), ctx.Repo.Repository.FullName(), sha)
+		if err != nil {
+			log.Error("Unable to get commits count for %s in %s. Error: %v", sha, ctx.Repo.Repository.FullName(), err)
+		}
+	}
+
+	return sha
+}
+
+// GetGitRefs return git references based on filter
+func GetGitRefs(ctx *context.APIContext, filter string) ([]*git.Reference, string, error) {
+	if ctx.Repo.GitRepo == nil {
+		return nil, "", fmt.Errorf("no open git repo found in context")
+	}
+	if len(filter) > 0 {
+		filter = "refs/" + filter
+	}
+	refs, err := ctx.Repo.GitRepo.GetRefsFiltered(filter)
+	return refs, "GetRefsFiltered", err
+}
+
+func searchRefCommitByType(ctx *context.APIContext, refType, filter string) (string, string, error) {
+	refs, lastMethodName, err := GetGitRefs(ctx, refType+"/"+filter) // Search by type
+	if err != nil {
+		return "", lastMethodName, err
+	}
+	if len(refs) > 0 {
+		return refs[0].Object.String(), "", nil // Return found SHA
+	}
+	return "", "", nil
+}
+
+// ConvertToObjectID returns a full-length SHA1 from a potential ID string
+func ConvertToObjectID(ctx gocontext.Context, repo *context.Repository, commitID string) (git.ObjectID, error) {
+	objectFormat := repo.GetObjectFormat()
+	if len(commitID) == objectFormat.FullLength() && objectFormat.IsValid(commitID) {
+		sha, err := git.NewIDFromString(commitID)
+		if err == nil {
+			return sha, nil
+		}
+	}
+
+	gitRepo, closer, err := gitrepo.RepositoryFromContextOrOpen(ctx, repo.Repository)
+	if err != nil {
+		return objectFormat.EmptyObjectID(), fmt.Errorf("RepositoryFromContextOrOpen: %w", err)
+	}
+	defer closer.Close()
+
+	return gitRepo.ConvertToGitID(commitID)
+}
+
+// MustConvertToSHA1 returns a full-length SHA1 string from a potential ID string, or returns origin input if it can't convert to SHA1
+func MustConvertToSHA1(ctx gocontext.Context, repo *context.Repository, commitID string) string {
+	sha, err := ConvertToObjectID(ctx, repo, commitID)
+	if err != nil {
+		return commitID
+	}
+	return sha.String()
+}