[GH-3410] Healthcheck Endpoint with Server Metadata (#4151)

* add ping endpoint and tests

* remove unnecessary newlines

* fix: invalid Swagger YAML comment blocks

* refactor and add 'suite' SKU

* generate swagger docs

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>
Co-authored-by: Paul Esch-Laurent <paul.esch-laurent@mattermost.com>

server/app/server_metadata.go

@@ -0,0 +1,42 @@
+package app
+
+import (
+	"runtime"
+
+	"github.com/mattermost/focalboard/server/model"
+)
+
+type ServerMetadata struct {
+	Version     string `json:"version"`
+	BuildNumber string `json:"build_number"`
+	BuildDate   string `json:"build_date"`
+	Commit      string `json:"commit"`
+	Edition     string `json:"edition"`
+	DBType      string `json:"db_type"`
+	DBVersion   string `json:"db_version"`
+	OSType      string `json:"os_type"`
+	OSArch      string `json:"os_arch"`
+	SKU         string `json:"sku"`
+}
+
+func (a *App) GetServerMetadata() *ServerMetadata {
+	var dbType string
+	var dbVersion string
+	if a != nil && a.store != nil {
+		dbType = a.store.DBType()
+		dbVersion = a.store.DBVersion()
+	}
+
+	return &ServerMetadata{
+		Version:     model.CurrentVersion,
+		BuildNumber: model.BuildNumber,
+		BuildDate:   model.BuildDate,
+		Commit:      model.BuildHash,
+		Edition:     model.Edition,
+		DBType:      dbType,
+		DBVersion:   dbVersion,
+		OSType:      runtime.GOOS,
+		OSArch:      runtime.GOARCH,
+		SKU:         "personal_server",
+	}
+}

server/app/server_metadata_test.go

@@ -0,0 +1,37 @@
+package app
+
+import (
+	"reflect"
+	"runtime"
+	"testing"
+
+	"github.com/mattermost/focalboard/server/model"
+)
+
+func TestGetServerMetadata(t *testing.T) {
+	th, tearDown := SetupTestHelper(t)
+	defer tearDown()
+
+	th.Store.EXPECT().DBType().Return("TEST_DB_TYPE")
+	th.Store.EXPECT().DBVersion().Return("TEST_DB_VERSION")
+
+	t.Run("Get Server Metadata", func(t *testing.T) {
+		got := th.App.GetServerMetadata()
+		want := &ServerMetadata{
+			Version:     model.CurrentVersion,
+			BuildNumber: model.BuildNumber,
+			BuildDate:   model.BuildDate,
+			Commit:      model.BuildHash,
+			Edition:     model.Edition,
+			DBType:      "TEST_DB_TYPE",
+			DBVersion:   "TEST_DB_VERSION",
+			OSType:      runtime.GOOS,
+			OSArch:      runtime.GOARCH,
+			SKU:         "personal_server",
+		}
+
+		if !reflect.DeepEqual(got, want) {
+			t.Errorf("got: %q, want: %q", got, want)
+		}
+	})
+}