Add API endpoint to get latest release (#21267)

This PR adds a new API endpoint to get the latest stable release of a
repo, similar to [GitHub
API](https://docs.github.com/en/rest/releases/releases#get-the-latest-release).

Author: JakobDev

Diff for: routers/api/v1/api.go

@@ -1011,6 +1011,7 @@ func Routes(ctx gocontext.Context) *web.Route {
 				m.Group("/releases", func() {
 					m.Combo("").Get(repo.ListReleases).
 						Post(reqToken(auth_model.AccessTokenScopeRepo), reqRepoWriter(unit.TypeReleases), context.ReferencesGitRepo(), bind(api.CreateReleaseOption{}), repo.CreateRelease)
+					m.Combo("/latest").Get(repo.GetLatestRelease)
 					m.Group("/{id}", func() {
 						m.Combo("").Get(repo.GetRelease).
 							Patch(reqToken(auth_model.AccessTokenScopeRepo), reqRepoWriter(unit.TypeReleases), context.ReferencesGitRepo(), bind(api.EditReleaseOption{}), repo.EditRelease).

Diff for: routers/api/v1/repo/release.go

@@ -67,6 +67,47 @@ func GetRelease(ctx *context.APIContext) {
 	ctx.JSON(http.StatusOK, convert.ToRelease(release))
 }
 
+// GetLatestRelease gets the most recent non-prerelease, non-draft release of a repository, sorted by created_at
+func GetLatestRelease(ctx *context.APIContext) {
+	// swagger:operation GET /repos/{owner}/{repo}/releases/latest repository repoGetLatestRelease
+	// ---
+	// summary: Gets the most recent non-prerelease, non-draft release of a repository, sorted by created_at
+	// produces:
+	// - application/json
+	// parameters:
+	// - name: owner
+	//   in: path
+	//   description: owner of the repo
+	//   type: string
+	//   required: true
+	// - name: repo
+	//   in: path
+	//   description: name of the repo
+	//   type: string
+	//   required: true
+	// responses:
+	//   "200":
+	//     "$ref": "#/responses/Release"
+	//   "404":
+	//     "$ref": "#/responses/notFound"
+	release, err := repo_model.GetLatestReleaseByRepoID(ctx.Repo.Repository.ID)
+	if err != nil && !repo_model.IsErrReleaseNotExist(err) {
+		ctx.Error(http.StatusInternalServerError, "GetLatestRelease", err)
+		return
+	}
+	if err != nil && repo_model.IsErrReleaseNotExist(err) ||
+		release.IsTag || release.RepoID != ctx.Repo.Repository.ID {
+		ctx.NotFound()
+		return
+	}
+
+	if err := release.LoadAttributes(ctx); err != nil {
+		ctx.Error(http.StatusInternalServerError, "LoadAttributes", err)
+		return
+	}
+	ctx.JSON(http.StatusOK, convert.ToRelease(release))
+}
+
 // ListReleases list a repository's releases
 func ListReleases(ctx *context.APIContext) {
 	// swagger:operation GET /repos/{owner}/{repo}/releases repository repoListReleases

Diff for: templates/swagger/v1_json.tmpl

@@ -9776,6 +9776,42 @@
         }
       }
     },
+    "/repos/{owner}/{repo}/releases/latest": {
+      "get": {
+        "produces": [
+          "application/json"
+        ],
+        "tags": [
+          "repository"
+        ],
+        "summary": "Gets the most recent non-prerelease, non-draft release of a repository, sorted by created_at",
+        "operationId": "repoGetLatestRelease",
+        "parameters": [
+          {
+            "type": "string",
+            "description": "owner of the repo",
+            "name": "owner",
+            "in": "path",
+            "required": true
+          },
+          {
+            "type": "string",
+            "description": "name of the repo",
+            "name": "repo",
+            "in": "path",
+            "required": true
+          }
+        ],
+        "responses": {
+          "200": {
+            "$ref": "#/responses/Release"
+          },
+          "404": {
+            "$ref": "#/responses/notFound"
+          }
+        }
+      }
+    },
     "/repos/{owner}/{repo}/releases/tags/{tag}": {
       "get": {
         "produces": [

Diff for: tests/integration/api_releases_test.go

@@ -176,6 +176,24 @@ func TestAPICreateReleaseToDefaultBranchOnExistingTag(t *testing.T) {
 	createNewReleaseUsingAPI(t, session, token, owner, repo, "v0.0.1", "", "v0.0.1", "test")
 }
 
+func TestAPIGetLatestRelease(t *testing.T) {
+	defer tests.PrepareTestEnv(t)()
+
+	repo := unittest.AssertExistsAndLoadBean(t, &repo_model.Repository{ID: 1})
+	owner := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: repo.OwnerID})
+
+	urlStr := fmt.Sprintf("/api/v1/repos/%s/%s/releases/latest",
+		owner.Name, repo.Name)
+
+	req := NewRequestf(t, "GET", urlStr)
+	resp := MakeRequest(t, req, http.StatusOK)
+
+	var release *api.Release
+	DecodeJSON(t, resp, &release)
+
+	assert.Equal(t, "testing-release", release.Title)
+}
+
 func TestAPIGetReleaseByTag(t *testing.T) {
 	defer tests.PrepareTestEnv(t)()