feat: bzz resource info API (#4588)

openapi/Swarm.yaml

@@ -179,6 +179,26 @@ paths:
           $ref: "SwarmCommon.yaml#/components/responses/400"
         default:
           description: Default response
+    head:
+      summary: Requests the headers containing the content type and length for the reference
+      tags:
+        - Bytes
+      parameters:
+        - in: path
+          name: address
+          schema:
+            $ref: "SwarmCommon.yaml#/components/schemas/SwarmAddress"
+          required: true
+          description: Swarm address of chunk
+      responses:
+        "200":
+          description: Chunk exists
+        "400":
+          $ref: "SwarmCommon.yaml#/components/responses/400"
+        "404":
+          $ref: "SwarmCommon.yaml#/components/responses/404"
+        default:
+          description: Default response
 
   "/chunks":
     post:
@@ -332,6 +352,26 @@ paths:
           $ref: "SwarmCommon.yaml#/components/responses/500"
         default:
           description: Default response
+    head:
+      summary: Get the headers containing the content type and length for the reference
+      tags:
+        - BZZ
+      parameters:
+        - in: path
+          name: address
+          schema:
+            $ref: "SwarmCommon.yaml#/components/schemas/SwarmAddress"
+          required: true
+          description: Swarm address of chunk
+      responses:
+        "200":
+          description: Chunk exists
+        "400":
+          $ref: "SwarmCommon.yaml#/components/responses/400"
+        "404":
+          $ref: "SwarmCommon.yaml#/components/responses/404"
+        default:
+          description: Default response
 
   "/bzz/{reference}/{path}":
     get:

pkg/api/bytes.go

@@ -153,7 +153,7 @@ func (s *Service) bytesGetHandler(w http.ResponseWriter, r *http.Request) {
 		ContentTypeHeader: {"application/octet-stream"},
 	}
 
-	s.downloadHandler(logger, w, r, paths.Address, additionalHeaders, true)
+	s.downloadHandler(logger, w, r, paths.Address, additionalHeaders, true, false)
 }
 
 func (s *Service) bytesHeadHandler(w http.ResponseWriter, r *http.Request) {

pkg/api/bzz.go

@@ -299,10 +299,29 @@ func (s *Service) bzzDownloadHandler(w http.ResponseWriter, r *http.Request) {
 		paths.Path = strings.TrimRight(paths.Path, "/") + "/" // NOTE: leave one slash if there was some.
 	}
 
-	s.serveReference(logger, paths.Address, paths.Path, w, r)
+	s.serveReference(logger, paths.Address, paths.Path, w, r, false)
 }
 
-func (s *Service) serveReference(logger log.Logger, address swarm.Address, pathVar string, w http.ResponseWriter, r *http.Request) {
+func (s *Service) bzzHeadHandler(w http.ResponseWriter, r *http.Request) {
+	logger := tracing.NewLoggerWithTraceID(r.Context(), s.logger.WithName("head_bzz_by_path").Build())
+
+	paths := struct {
+		Address swarm.Address `map:"address,resolve" validate:"required"`
+		Path    string        `map:"path"`
+	}{}
+	if response := s.mapStructure(mux.Vars(r), &paths); response != nil {
+		response("invalid path params", logger, w)
+		return
+	}
+
+	if strings.HasSuffix(paths.Path, "/") {
+		paths.Path = strings.TrimRight(paths.Path, "/") + "/" // NOTE: leave one slash if there was some.
+	}
+
+	s.serveReference(logger, paths.Address, paths.Path, w, r, true)
+}
+
+func (s *Service) serveReference(logger log.Logger, address swarm.Address, pathVar string, w http.ResponseWriter, r *http.Request, headerOnly bool) {
 	loggerV1 := logger.V(1).Build()
 
 	headers := struct {
@@ -404,7 +423,7 @@ FETCH:
 				// index document exists
 				logger.Debug("bzz download: serving path", "path", pathWithIndex)
 
-				s.serveManifestEntry(logger, w, r, indexDocumentManifestEntry, !feedDereferenced)
+				s.serveManifestEntry(logger, w, r, indexDocumentManifestEntry, !feedDereferenced, headerOnly)
 				return
 			}
 		}
@@ -447,7 +466,7 @@ FETCH:
 						// index document exists
 						logger.Debug("bzz download: serving path", "path", pathWithIndex)
 
-						s.serveManifestEntry(logger, w, r, indexDocumentManifestEntry, !feedDereferenced)
+						s.serveManifestEntry(logger, w, r, indexDocumentManifestEntry, !feedDereferenced, headerOnly)
 						return
 					}
 				}
@@ -461,7 +480,7 @@ FETCH:
 						// error document exists
 						logger.Debug("bzz download: serving path", "path", errorDocumentPath)
 
-						s.serveManifestEntry(logger, w, r, errorDocumentManifestEntry, !feedDereferenced)
+						s.serveManifestEntry(logger, w, r, errorDocumentManifestEntry, !feedDereferenced, headerOnly)
 						return
 					}
 				}
@@ -475,15 +494,15 @@ FETCH:
 	}
 
 	// serve requested path
-	s.serveManifestEntry(logger, w, r, me, !feedDereferenced)
+	s.serveManifestEntry(logger, w, r, me, !feedDereferenced, headerOnly)
 }
 
 func (s *Service) serveManifestEntry(
 	logger log.Logger,
 	w http.ResponseWriter,
 	r *http.Request,
 	manifestEntry manifest.Entry,
-	etag bool,
+	etag, headersOnly bool,
 ) {
 	additionalHeaders := http.Header{}
 	mtdt := manifestEntry.Metadata()
@@ -496,11 +515,11 @@ func (s *Service) serveManifestEntry(
 		additionalHeaders[ContentTypeHeader] = []string{mimeType}
 	}
 
-	s.downloadHandler(logger, w, r, manifestEntry.Reference(), additionalHeaders, etag)
+	s.downloadHandler(logger, w, r, manifestEntry.Reference(), additionalHeaders, etag, headersOnly)
 }
 
 // downloadHandler contains common logic for dowloading Swarm file from API
-func (s *Service) downloadHandler(logger log.Logger, w http.ResponseWriter, r *http.Request, reference swarm.Address, additionalHeaders http.Header, etag bool) {
+func (s *Service) downloadHandler(logger log.Logger, w http.ResponseWriter, r *http.Request, reference swarm.Address, additionalHeaders http.Header, etag, headersOnly bool) {
 	headers := struct {
 		Strategy              *getter.Strategy `map:"Swarm-Redundancy-Strategy"`
 		FallbackMode          *bool            `map:"Swarm-Redundancy-Fallback-Mode"`
@@ -551,6 +570,12 @@ func (s *Service) downloadHandler(logger log.Logger, w http.ResponseWriter, r *h
 	}
 	w.Header().Set(ContentLengthHeader, strconv.FormatInt(l, 10))
 	w.Header().Set("Access-Control-Expose-Headers", ContentDispositionHeader)
+
+	if headersOnly {
+		w.WriteHeader(http.StatusOK)
+		return
+	}
+
 	bufSize := lookaheadBufferSize(l)
 	if headers.LookaheadBufferSize != nil {
 		bufSize = *(headers.LookaheadBufferSize)

pkg/api/bzz_test.go

@@ -521,8 +521,18 @@ func TestBzzFiles(t *testing.T) {
 			jsonhttptest.WithRequestHeader(api.ContentTypeHeader, "text/html; charset=utf-8"),
 			jsonhttptest.WithNonEmptyResponseHeader(api.SwarmTagHeader),
 		)
-	})
 
+		t.Run("head", func(t *testing.T) {
+			rootHash := "65148cd89b58e91616773f5acea433f7b5a6274f2259e25f4893a332b74a7e28"
+
+			jsonhttptest.Request(t, client, http.MethodHead, fileDownloadResource(rootHash), http.StatusOK,
+				jsonhttptest.WithRequestHeader(api.SwarmPostageBatchIdHeader, batchOkStr),
+				jsonhttptest.WithRequestBody(bytes.NewReader(simpleData)),
+				jsonhttptest.WithRequestHeader(api.ContentTypeHeader, "text/html; charset=utf-8"),
+				jsonhttptest.WithExpectedContentLength(21),
+			)
+		})
+	})
 }
 
 // TestRangeRequests validates that all endpoints are serving content with

pkg/api/cors_test.go

@@ -137,7 +137,7 @@ func TestCors(t *testing.T) {
 			expectedMethods: "POST",
 		}, {
 			endpoint:        "bzz/0101011",
-			expectedMethods: "GET",
+			expectedMethods: "GET, HEAD",
 		},
 		{
 			endpoint:        "chunks",

pkg/api/router.go

@@ -270,6 +270,9 @@ func (s *Service) mountAPI() {
 			s.newTracingHandler("bzz-download"),
 			web.FinalHandlerFunc(s.bzzDownloadHandler),
 		),
+		"HEAD": web.ChainHandlers(
+			web.FinalHandlerFunc(s.bzzHeadHandler),
+		),
 	})
 
 	handle("/pss/send/{topic}/{targets}", web.ChainHandlers(

pkg/api/subdomain.go

@@ -28,5 +28,5 @@ func (s *Service) subdomainHandler(w http.ResponseWriter, r *http.Request) {
 		paths.Path = strings.TrimRight(paths.Path, "/") + "/" // NOTE: leave one slash if there was some.
 	}
 
-	s.serveReference(logger, paths.Subdomain, paths.Path, w, r)
+	s.serveReference(logger, paths.Subdomain, paths.Path, w, r, false)
 }

pkg/auth/auth.go

@@ -242,15 +242,15 @@ func (e encrypter) decrypt(data []byte) ([]byte, error) {
 
 func applyPolicies(e *casbin.Enforcer) error {
 	_, err := e.AddPolicies([][]string{
-		{"consumer", "/bytes/*", "GET"},
+		{"consumer", "/bytes/*", "(GET)|(HEAD)"},
 		{"creator", "/bytes", "POST"},
 		{"consumer", "/chunks/*", "GET"},
 		{"creator", "/chunks", "POST"},
 		{"consumer", "/bzz/*", "GET"},
 		{"creator", "/bzz/*", "PATCH"},
 		{"creator", "/bzz", "POST"},
 		{"creator", "/bzz?*", "POST"},
-		{"consumer", "/bzz/*/*", "GET"},
+		{"consumer", "/bzz/*/*", "(GET)|(HEAD)"},
 		{"creator", "/tags", "GET"},
 		{"creator", "/tags?*", "GET"},
 		{"creator", "/tags", "POST"},