feat(debugapi, postage): dilute batch handling

openapi/SwarmDebug.yaml

@@ -908,3 +908,38 @@ paths:
           $ref: "SwarmCommon.yaml#/components/responses/500"
         default:
           description: Default response
+
+  "/stamps/dilute/{id}/{depth}":
+    patch:
+      summary: Dilute an existing postage batch.
+      description: Be aware, this endpoint creates on-chain transactions and transfers BZZ from the node's Ethereum account and hence directly manipulates the wallet balance!
+      tags:
+        - Postage Stamps
+      parameters:
+        - in: path
+          name: id
+          schema:
+            $ref: "SwarmCommon.yaml#/components/schemas/BatchID"
+          required: true
+          description: Batch ID to dilute
+        - in: path
+          name: depth
+          schema:
+            type: integer
+          required: true
+          description: New batch depth. Must be higher than the previous depth.
+      responses:
+        "202":
+          description: Returns the postage batch ID that was diluted.
+          content:
+            application/json:
+              schema:
+                $ref: "SwarmCommon.yaml#/components/schemas/BatchIDResponse"
+        "400":
+          $ref: "SwarmCommon.yaml#/components/responses/400"
+        "429":
+          $ref: "SwarmCommon.yaml#/components/responses/429"
+        "500":
+          $ref: "SwarmCommon.yaml#/components/responses/500"
+        default:
+          description: Default response

pkg/debugapi/debugapi.go

@@ -69,7 +69,7 @@ type Service struct {
 
 	// The following are semaphores which exists to limit concurrent access
 	// to some parts of the resources in order to avoid undefined behaviour.
-	postageCreateSem *semaphore.Weighted
+	postageSem       *semaphore.Weighted
 	cashOutChequeSem *semaphore.Weighted
 }
 
@@ -88,7 +88,7 @@ func New(publicKey, pssPublicKey ecdsa.PublicKey, ethereumAddress common.Address
 	s.blockTime = blockTime
 	s.metricsRegistry = newMetricsRegistry()
 	s.transaction = transaction
-	s.postageCreateSem = semaphore.NewWeighted(1)
+	s.postageSem = semaphore.NewWeighted(1)
 	s.cashOutChequeSem = semaphore.NewWeighted(1)
 
 	s.setRouter(s.newBasicRouter())

pkg/debugapi/postage.go

@@ -21,6 +21,20 @@ import (
 	"github.com/gorilla/mux"
 )
 
+func (s *Service) postageAccessHandler(h http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if !s.postageSem.TryAcquire(1) {
+			s.logger.Debug("postage access: simultaneous on-chain operations not supported")
+			s.logger.Error("postage access: simultaneous on-chain operations not supported")
+			jsonhttp.TooManyRequests(w, "simultaneous on-chain operations not supported")
+			return
+		}
+		defer s.postageSem.Release(1)
+
+		h.ServeHTTP(w, r)
+	})
+}
+
 type batchID []byte
 
 func (b batchID) MarshalJSON() ([]byte, error) {
@@ -68,14 +82,6 @@ func (s *Service) postageCreateHandler(w http.ResponseWriter, r *http.Request) {
 		immutable, _ = strconv.ParseBool(val[0])
 	}
 
-	if !s.postageCreateSem.TryAcquire(1) {
-		s.logger.Debug("create batch: simultaneous on-chain operations not supported")
-		s.logger.Error("create batch: simultaneous on-chain operations not supported")
-		jsonhttp.TooManyRequests(w, "simultaneous on-chain operations not supported")
-		return
-	}
-	defer s.postageCreateSem.Release(1)
-
 	batchID, err := s.postageContract.CreateBatch(ctx, amount, uint8(depth), immutable, label)
 	if err != nil {
 		if errors.Is(err, postagecontract.ErrInsufficientFunds) {
@@ -324,7 +330,7 @@ func (s *Service) estimateBatchTTL(id []byte) (int64, error) {
 
 func (s *Service) postageTopUpHandler(w http.ResponseWriter, r *http.Request) {
 	idStr := mux.Vars(r)["id"]
-	if idStr == "" || len(idStr) != 64 {
+	if len(idStr) != 64 {
 		s.logger.Error("topup batch: invalid batchID")
 		jsonhttp.BadRequest(w, "invalid batchID")
 		return
@@ -355,14 +361,6 @@ func (s *Service) postageTopUpHandler(w http.ResponseWriter, r *http.Request) {
 		ctx = sctx.SetGasPrice(ctx, p)
 	}
 
-	if !s.postageCreateSem.TryAcquire(1) {
-		s.logger.Debug("topup batch: simultaneous on-chain operations not supported")
-		s.logger.Error("topup batch: simultaneous on-chain operations not supported")
-		jsonhttp.TooManyRequests(w, "simultaneous on-chain operations not supported")
-		return
-	}
-	defer s.postageCreateSem.Release(1)
-
 	err = s.postageContract.TopUpBatch(ctx, id, amount)
 	if err != nil {
 		if errors.Is(err, postagecontract.ErrInsufficientFunds) {
@@ -381,3 +379,57 @@ func (s *Service) postageTopUpHandler(w http.ResponseWriter, r *http.Request) {
 		BatchID: id,
 	})
 }
+
+func (s *Service) postageDiluteHandler(w http.ResponseWriter, r *http.Request) {
+	idStr := mux.Vars(r)["id"]
+	if len(idStr) != 64 {
+		s.logger.Error("dilute batch: invalid batchID")
+		jsonhttp.BadRequest(w, "invalid batchID")
+		return
+	}
+	id, err := hex.DecodeString(idStr)
+	if err != nil {
+		s.logger.Debugf("dilute batch: invalid batchID: %v", err)
+		s.logger.Error("dilute batch: invalid batchID")
+		jsonhttp.BadRequest(w, "invalid batchID")
+		return
+	}
+
+	depthStr := mux.Vars(r)["depth"]
+	depth, err := strconv.ParseUint(depthStr, 10, 8)
+	if err != nil {
+		s.logger.Debugf("dilute batch: invalid depth: %v", err)
+		s.logger.Error("dilute batch: invalid depth")
+		jsonhttp.BadRequest(w, "invalid depth")
+		return
+	}
+
+	ctx := r.Context()
+	if price, ok := r.Header[gasPriceHeader]; ok {
+		p, ok := big.NewInt(0).SetString(price[0], 10)
+		if !ok {
+			s.logger.Error("dilute batch: bad gas price")
+			jsonhttp.BadRequest(w, errBadGasPrice)
+			return
+		}
+		ctx = sctx.SetGasPrice(ctx, p)
+	}
+
+	err = s.postageContract.DiluteBatch(ctx, id, uint8(depth))
+	if err != nil {
+		if errors.Is(err, postagecontract.ErrInvalidDepth) {
+			s.logger.Debugf("dilute batch: invalid depth: %v", err)
+			s.logger.Error("dilte batch: invalid depth")
+			jsonhttp.BadRequest(w, "invalid depth")
+			return
+		}
+		s.logger.Debugf("dilute batch: failed to dilute: %v", err)
+		s.logger.Error("dilute batch: failed to dilute")
+		jsonhttp.InternalServerError(w, "cannot dilute batch")
+		return
+	}
+
+	jsonhttp.Accepted(w, &postageCreateResponse{
+		BatchID: id,
+	})
+}