docs: Add support for emoji reactions to posts.

go.mod

@@ -55,6 +55,7 @@ require (
 	golang.org/x/mod v0.4.2 // indirect
 	golang.org/x/net v0.0.0-20210614182718-04defd469f4e // indirect
 	golang.org/x/sync v0.0.0-20210220032951-036812b2e83c // indirect
+	golang.org/x/text v0.3.7 // indirect
 	golang.org/x/time v0.0.0-20201208040808-7e3f01d25324 // indirect
 	golang.org/x/tools v0.1.0 // indirect
 	gopkg.in/DataDog/dd-trace-go.v1 v1.29.0

go.sum

@@ -665,6 +665,8 @@ golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.6 h1:aRYxNxv6iGQlyVaZmk6ZgYEDa+Jg18DxebPSrd6bg1M=
 golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
+golang.org/x/text v0.3.7 h1:olpwvP2KacW1ZWvsR7uQhoyTYvKAupfQrRGBFM352Gk=
+golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
 golang.org/x/time v0.0.0-20181108054448-85acf8d2951c/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
 golang.org/x/time v0.0.0-20190308202827-9d24e82272b4/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
 golang.org/x/time v0.0.0-20201208040808-7e3f01d25324 h1:Hir2P/De0WpUhtrKGGjvSb2YxUgyZ7EFOSLIcSSpiwE=

lib/block_view.go

@@ -64,6 +64,9 @@ type UtxoView struct {
 	// Like data
 	LikeKeyToLikeEntry map[LikeKey]*LikeEntry
 
+	// React data
+	ReactionKeyToReactionEntry map[ReactionKey]*ReactionEntry
+
 	// Repost data
 	RepostKeyToRepostEntry map[RepostKey]*RepostEntry
 
@@ -145,6 +148,9 @@ func (bav *UtxoView) _ResetViewMappingsAfterFlush() {
 	// Like data
 	bav.LikeKeyToLikeEntry = make(map[LikeKey]*LikeEntry)
 
+	// React data
+	bav.ReactionKeyToReactionEntry = make(map[ReactionKey]*ReactionEntry)
+
 	// Repost data
 	bav.RepostKeyToRepostEntry = make(map[RepostKey]*RepostEntry)
 
@@ -281,6 +287,16 @@ func (bav *UtxoView) CopyUtxoView() (*UtxoView, error) {
 		newView.LikeKeyToLikeEntry[likeKey] = &newLikeEntry
 	}
 
+	// Copy the react data
+	newView.ReactionKeyToReactionEntry = make(map[ReactionKey]*ReactionEntry, len(bav.ReactionKeyToReactionEntry))
+	for reactKey, reactEntry := range bav.ReactionKeyToReactionEntry {
+		if reactEntry == nil {
+			continue
+		}
+		newReactEntry := *reactEntry
+		newView.ReactionKeyToReactionEntry[reactKey] = &newReactEntry
+	}
+
 	// Copy the repost data
 	newView.RepostKeyToRepostEntry = make(map[RepostKey]*RepostEntry, len(bav.RepostKeyToRepostEntry))
 	for repostKey, repostEntry := range bav.RepostKeyToRepostEntry {
@@ -947,6 +963,10 @@ func (bav *UtxoView) DisconnectTransaction(currentTxn *MsgDeSoTxn, txnHash *Bloc
 		return bav._disconnectLike(
 			OperationTypeLike, currentTxn, txnHash, utxoOpsForTxn, blockHeight)
 
+	} else if currentTxn.TxnMeta.GetTxnType() == TxnTypeReact {
+		return bav._disconnectReact(
+			OperationTypeReact, currentTxn, txnHash, utxoOpsForTxn, blockHeight)
+
 	} else if currentTxn.TxnMeta.GetTxnType() == TxnTypeCreatorCoin {
 		return bav._disconnectCreatorCoin(
 			OperationTypeCreatorCoin, currentTxn, txnHash, utxoOpsForTxn, blockHeight)
@@ -2257,6 +2277,10 @@ func (bav *UtxoView) _connectTransaction(txn *MsgDeSoTxn, txHash *BlockHash,
 		totalInput, totalOutput, utxoOpsForTxn, err =
 			bav._connectLike(txn, txHash, blockHeight, verifySignatures)
 
+	} else if txn.TxnMeta.GetTxnType() == TxnTypeReact {
+		totalInput, totalOutput, utxoOpsForTxn, err =
+			bav._connectReact(txn, txHash, blockHeight, verifySignatures)
+
 	} else if txn.TxnMeta.GetTxnType() == TxnTypeCreatorCoin {
 		totalInput, totalOutput, utxoOpsForTxn, err =
 			bav._connectCreatorCoin(

lib/block_view_flush.go

@@ -66,6 +66,9 @@ func (bav *UtxoView) FlushToDbWithTxn(txn *badger.Txn, blockHeight uint64) error
 		if err := bav._flushLikeEntriesToDbWithTxn(txn); err != nil {
 			return err
 		}
+		if err := bav._flushReactEntriesToDbWithTxn(txn); err != nil {
+			return err
+		}
 		if err := bav._flushFollowEntriesToDbWithTxn(txn); err != nil {
 			return err
 		}
@@ -411,6 +414,53 @@ func (bav *UtxoView) _flushLikeEntriesToDbWithTxn(txn *badger.Txn) error {
 	return nil
 }
 
+func (bav *UtxoView) _flushReactEntriesToDbWithTxn(txn *badger.Txn) error {
+
+	// Go through all the entries in the ReactionKeyToReactionEntry map.
+	for reactKeyIter, reactEntry := range bav.ReactionKeyToReactionEntry {
+		// Make a copy of the iterator since we make references to it below.
+		reactKey := reactKeyIter
+
+		// Sanity-check that the ReactKey computed from the ReactEntry is
+		// equal to the ReactKey that maps to that entry.
+		reactKeyInEntry := MakeReactionKey(reactEntry.ReactorPubKey, *reactEntry.ReactedPostHash, reactEntry.ReactEmoji)
+		if reactKeyInEntry != reactKey {
+			return fmt.Errorf("_flushReactEntriesToDbWithTxn: ReactEntry has "+
+				"ReactKey: %v, which doesn't match the ReactKeyToReactEntry map key %v",
+				&reactKeyInEntry, &reactKey)
+		}
+
+		// Delete the existing mappings in the db for this ReactKey. They will be re-added
+		// if the corresponding entry in memory has isDeleted=false.
+		if err := DbDeleteReactMappingsWithTxn(
+			txn, reactKey.ReactorPubKey[:], reactKey.ReactedPostHash, reactKey.ReactEmoji); err != nil {
+
+			return errors.Wrapf(
+				err, "_flushReactEntriesToDbWithTxn: Problem deleting mappings "+
+					"for LikeKey: %v: ", &reactKey)
+		}
+	}
+
+	// Go through all the entries in the LikeKeyToLikeEntry map.
+	for _, reactEntry := range bav.ReactionKeyToReactionEntry {
+
+		if reactEntry.isDeleted {
+			// If the LikeEntry has isDeleted=true then there's nothing to do because
+			// we already deleted the entry above.
+		} else {
+			// If the LikeEntry has (isDeleted = false) then we put the corresponding
+			// mappings for it into the db.
+			if err := DbPutReactMappingsWithTxn(
+				txn, reactEntry.ReactorPubKey, *reactEntry.ReactedPostHash, reactEntry.ReactEmoji); err != nil {
+
+				return err
+			}
+		}
+	}
+
+	return nil
+}
+
 func (bav *UtxoView) _flushFollowEntriesToDbWithTxn(txn *badger.Txn) error {
 
 	// Go through all the entries in the FollowKeyToFollowEntry map.