request epoch start block

process/block/export_test.go

@@ -909,6 +909,11 @@ func (sp *shardProcessor) CheckEpochStartInfoAvailableIfNeeded(header data.Shard
 	return sp.checkEpochStartInfoAvailableIfNeeded(header)
 }
 
+// EnsureEpochStartInfoAvailable -
+func (sp *shardProcessor) EnsureEpochStartInfoAvailable(header data.ShardHeaderHandler, haveTime func() time.Duration) error {
+	return sp.ensureEpochStartInfoAvailable(header, haveTime)
+}
+
 // HeadersPool -
 func (sp *shardProcessor) HeadersPool() dataRetriever.HeadersPool {
 	return sp.dataPool.Headers()

process/block/shardblock.go

@@ -301,6 +301,36 @@ func (sp *shardProcessor) checkEpochStartInfoAvailableIfNeeded(header data.Shard
 	return nil
 }
 
+func (sp *shardProcessor) ensureEpochStartInfoAvailable(header data.ShardHeaderHandler, haveTime func() time.Duration) error {
+	err := sp.checkEpochStartInfoAvailableIfNeeded(header)
+	if err == nil {
+		return nil
+	}
+
+	log.Warn("epoch start info missing at execution, requesting",
+		"epochStartMetaHash", header.GetEpochStartMetaHash(),
+		"error", err,
+	)
+
+	requestCount := 0
+	for haveTime() > 0 {
+		requestCount++
+		if requestCount%5 == 1 {
+			go sp.requestHandler.RequestMetaHeader(header.GetEpochStartMetaHash())
+			sp.requestEpochStartProofIfNeeded(header.GetEpochStartMetaHash(), header.GetEpoch())
+		}
+
+		time.Sleep(timeBetweenCheckForEpochStart)
+
+		err = sp.checkEpochStartInfoAvailableIfNeeded(header)
+		if err == nil {
+			return nil
+		}
+	}
+
+	return err
+}
+
 func (sp *shardProcessor) requestEpochStartInfo(header data.ShardHeaderHandler, haveTime func() time.Duration) error {
 	if !sp.shouldEpochStartInfoBeAvailable(header) {
 		return nil

process/block/shardblockProposal.go

@@ -338,8 +338,7 @@ func (sp *shardProcessor) ProcessBlockProposal(
 		return nil, err
 	}
 
-	// TODO: improvement - add also a request if it is missing as a fallback, although it should not be missing at this point
-	err = sp.checkEpochStartInfoAvailableIfNeeded(header)
+	err = sp.ensureEpochStartInfoAvailable(header, haveTime)
 	if err != nil {
 		return nil, err
 	}