Full MVC of gitlab-zoekt-indexer

cmd/gitlab-zoekt-indexer/main.go

@@ -6,7 +6,6 @@ import (
 	"errors"
 	"flag"
 	"fmt"
-	"io"
 	"log"
 	"net/http"
 	"os"
@@ -19,6 +18,7 @@ import (
 	"github.com/prometheus/client_golang/prometheus/collectors"
 	"github.com/prometheus/client_golang/prometheus/promauto"
 	"github.com/prometheus/client_golang/prometheus/promhttp"
+	"gitlab.com/gitlab-org/search-team/gitlab-zoekt-indexer/correlation"
 	"gitlab.com/gitlab-org/search-team/gitlab-zoekt-indexer/indexer"
 )
 
@@ -29,6 +29,7 @@ type options struct {
 
 type indexServer struct {
 	indexDir             string
+	indexBuilder         indexBuilder
 	promRegistry         *prometheus.Registry
 	metricsRequestsTotal *prometheus.CounterVec
 }
@@ -43,11 +44,50 @@ type gitalyConnectionInfo struct {
 type indexRequest struct {
 	Timeout              string
 	RepoID               uint32
-	CorrelationID        string
 	GitalyConnectionInfo *gitalyConnectionInfo
 	FileSizeLimit        int
 }
 
+type indexBuilder interface {
+	indexRepository(ctx context.Context, req indexRequest, indexDir string) error
+}
+
+type defaultIndexBuilder struct{}
+
+func (b defaultIndexBuilder) indexRepository(ctx context.Context, req indexRequest, indexDir string) error {
+	if req.GitalyConnectionInfo == nil {
+		return errors.New("gitalyConnectionInfo is not set")
+	}
+
+	if req.FileSizeLimit == 0 {
+		return errors.New("fileSizeLimit is not set")
+	}
+
+	timeout, err := time.ParseDuration(req.Timeout)
+	if err != nil {
+		return fmt.Errorf("failed to parse Timeout: %v with error %v", req.Timeout, err)
+	}
+
+	ctx, cancel := context.WithTimeout(ctx, timeout)
+	defer cancel()
+
+	idx := &indexer.Indexer{
+		IndexDir:           indexDir,
+		ProjectID:          req.RepoID,
+		CorrelationID:      correlation.GetCorrelationID(ctx),
+		GitalyAddress:      req.GitalyConnectionInfo.Address,
+		GitalyStorageName:  req.GitalyConnectionInfo.Storage,
+		GitalyRelativePath: req.GitalyConnectionInfo.Path,
+		LimitFileSize:      req.FileSizeLimit,
+	}
+
+	if err := idx.IndexRepository(ctx); err != nil {
+		return err
+	}
+
+	return nil
+}
+
 func (s *indexServer) createIndexDir() {
 	if err := os.MkdirAll(s.indexDir, 0o755); err != nil {
 		log.Fatalf("createIndexDir %s: %v", s.indexDir, err)
@@ -57,6 +97,11 @@ func (s *indexServer) createIndexDir() {
 func (s *indexServer) handleStatus() http.HandlerFunc {
 	route := "status"
 
+	type response struct {
+		Success bool
+		SHA     string
+	}
+
 	return func(w http.ResponseWriter, r *http.Request) {
 		param := chi.URLParam(r, "id")
 		repoID, err := strconv.ParseUint(param, 10, 32)
@@ -83,12 +128,12 @@ func (s *indexServer) handleStatus() http.HandlerFunc {
 			return
 		}
 
-		response := map[string]any{
-			"Success": true,
-			"SHA":     currentSHA,
+		resp := response{
+			Success: true,
+			SHA:     currentSHA,
 		}
 
-		s.respondWith(w, r, route, response)
+		s.respondWith(w, r, route, resp)
 	}
 }
 
@@ -98,79 +143,76 @@ func (s *indexServer) handleMetrics() http.HandlerFunc {
 	}
 }
 
+func (s *indexServer) decode(r *http.Request, v interface{}) error {
+	dec := json.NewDecoder(r.Body)
+	dec.DisallowUnknownFields()
+	return dec.Decode(v)
+}
+
 func (s *indexServer) handleIndex() http.HandlerFunc {
 	route := "index"
 
-	parseRequest := func(r io.Reader) (indexRequest, error) {
-		dec := json.NewDecoder(r)
-		dec.DisallowUnknownFields()
+	type response struct {
+		Success bool
+	}
+
+	parseRequest := func(r *http.Request) (indexRequest, error) {
 		var req indexRequest
-		err := dec.Decode(&req)
+		err := s.decode(r, &req)
 
 		if err != nil {
 			return req, errors.New("json parser error")
 		}
 
-		if req.GitalyConnectionInfo == nil {
-			return req, errors.New("gitalyConnectionInfo Error")
-		}
-
-		if req.FileSizeLimit == 0 {
-			return req, errors.New("fileSizeLimit is not set")
-		}
-
 		return req, nil
 	}
 
 	return func(w http.ResponseWriter, r *http.Request) {
-		req, err := parseRequest(r.Body)
+		req, err := parseRequest(r)
 		if err != nil {
 			http.Error(w, err.Error(), http.StatusBadRequest)
 			return
 		}
 
-		err = s.indexRepository(req)
+		err = s.indexBuilder.indexRepository(r.Context(), req, s.indexDir)
 		if err != nil {
 			s.respondWithError(w, r, route, err)
 			return
 		}
 
-		response := map[string]any{
-			"Success": true,
+		resp := response{
+			Success: true,
 		}
 
-		s.respondWith(w, r, route, response)
+		s.respondWith(w, r, route, resp)
 	}
 }
 
-func (s *indexServer) indexRepository(req indexRequest) error {
-	timeout, err := time.ParseDuration(req.Timeout)
-	if err != nil {
-		return fmt.Errorf("failed to parse Timeout: %v with error %v", req.Timeout, err)
+func (s *indexServer) handleTruncate() http.HandlerFunc {
+	route := "truncate"
+
+	type response struct {
+		Success bool
 	}
 
-	ctx, cancel := context.WithTimeout(context.Background(), timeout)
-	defer cancel()
+	emptyDirectory := func(dir string) error {
+		files, err := os.ReadDir(dir)
 
-	idx := &indexer.Indexer{
-		IndexDir:           s.indexDir,
-		ProjectID:          req.RepoID,
-		CorrelationID:      req.CorrelationID,
-		GitalyAddress:      req.GitalyConnectionInfo.Address,
-		GitalyStorageName:  req.GitalyConnectionInfo.Storage,
-		GitalyRelativePath: req.GitalyConnectionInfo.Path,
-		LimitFileSize:      req.FileSizeLimit,
-	}
+		if err != nil {
+			return err
+		}
 
-	if err := idx.IndexRepository(ctx); err != nil {
-		return err
-	}
+		for _, file := range files {
+			filePath := filepath.Join(dir, file.Name())
+			err := os.RemoveAll(filePath)
+			if err != nil {
+				return err
+			}
+		}
 
-	return nil
-}
+		return nil
+	}
 
-func (s *indexServer) handleTruncate() http.HandlerFunc {
-	route := "truncate"
 	return func(w http.ResponseWriter, r *http.Request) {
 		err := emptyDirectory(s.indexDir)
 
@@ -181,11 +223,11 @@ func (s *indexServer) handleTruncate() http.HandlerFunc {
 			return
 		}
 
-		response := map[string]any{
-			"Success": true,
+		resp := response{
+			Success: true,
 		}
 
-		s.respondWith(w, r, route, response)
+		s.respondWith(w, r, route, resp)
 	}
 }
 
@@ -194,24 +236,31 @@ func (s *indexServer) respondWith(w http.ResponseWriter, r *http.Request, route
 
 	if err := json.NewEncoder(w).Encode(data); err != nil {
 		s.respondWithError(w, r, route, err)
+		return
 	}
 
 	s.incrementRequestsTotal(r.Method, route, http.StatusOK)
 }
 
 func (s *indexServer) respondWithError(w http.ResponseWriter, r *http.Request, route string, err error) {
-	responseCode := http.StatusInternalServerError
+	type response struct {
+		Success bool
+		Error   string
+	}
 
-	s.incrementRequestsTotal(r.Method, route, responseCode)
+	responseCode := http.StatusInternalServerError
 
 	w.Header().Set("Content-Type", "application/json")
 	w.WriteHeader(responseCode)
-	response := map[string]any{
-		"Success": false,
-		"Error":   err.Error(),
+
+	resp := response{
+		Success: false,
+		Error:   err.Error(),
 	}
 
-	_ = json.NewEncoder(w).Encode(response)
+	_ = json.NewEncoder(w).Encode(resp)
+
+	s.incrementRequestsTotal(r.Method, route, responseCode)
 }
 
 func (s *indexServer) incrementRequestsTotal(method, route string, responseCode int) {
@@ -236,24 +285,6 @@ func (s *indexServer) initMetrics() {
 	)
 }
 
-func emptyDirectory(dir string) error {
-	files, err := os.ReadDir(dir)
-
-	if err != nil {
-		return err
-	}
-
-	for _, file := range files {
-		filePath := filepath.Join(dir, file.Name())
-		err := os.RemoveAll(filePath)
-		if err != nil {
-			return err
-		}
-	}
-
-	return nil
-}
-
 func parseOptions() options {
 	indexDir := flag.String("index_dir", "", "directory holding index shards.")
 	listen := flag.String("listen", ":6060", "listen on this address.")
@@ -273,7 +304,8 @@ func main() {
 	opts := parseOptions()
 
 	server := indexServer{
-		indexDir: opts.indexDir,
+		indexDir:     opts.indexDir,
+		indexBuilder: defaultIndexBuilder{},
 	}
 
 	server.startIndexingApi(opts.listen)
@@ -282,11 +314,15 @@ func main() {
 func (s *indexServer) startIndexingApi(listen string) {
 	s.initMetrics()
 	s.createIndexDir()
-	router := s.router()
+
+	httpServer := http.Server{
+		Addr:    listen,
+		Handler: s.router(),
+	}
 
 	log.Printf("Starting server on %s", listen)
 
-	if err := http.ListenAndServe(listen, router); err != nil {
+	if err := httpServer.ListenAndServe(); err != nil {
 		log.Fatal(err)
 	}
 }