Add block rewards.

services/execdb/filters.go

@@ -124,6 +124,37 @@ type BlockFilter struct {
 	FeeRecipients *[][]byte
 }
 
+// BlockRewardFilter defines a filter for fetching block rewards.
+// Filter elements are ANDed together.
+// Results are always returned in ascending block height order.
+type BlockRewardFilter struct {
+	// Limit is the maximum number of block rewards to return.
+	// If 0 then there is no limit.
+	Limit uint32
+
+	// Order is either OrderEarliest, in which case the earliest results
+	// that match the filter are returned, or OrderLatest, in which case the
+	// latest results that match the filter are returned.
+	// The default is OrderEarliest.
+	Order Order
+
+	// From is the height of the earliest block reward to fetch.
+	// If nil then there is no earliest block.
+	From *uint32
+
+	// TimestampTo is the height of the latest block reward to fetch.
+	// If nil then there is no latest block.
+	To *uint32
+
+	// From is the timestamp of the earliest block reward to fetch.
+	// If nil then there is no earliest block.
+	TimestampFrom *time.Time
+
+	// TimestampTo is the timestamp of the latest block reward to fetch.
+	// If nil then there is no latest block.
+	TimestampTo *time.Time
+}
+
 // EventFilter defines a filter for fetching events.
 // Filter elements are ANDed together.
 // Results are always returned in ascending (block height, transaction index, event index) order.

services/execdb/postgresql/blockrewards.go

@@ -0,0 +1,136 @@
+// Copyright © 2024 Weald Technology Trading.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package postgresql
+
+import (
+	"context"
+	"fmt"
+	"sort"
+	"strings"
+
+	"github.com/pkg/errors"
+	"github.com/wealdtech/execd/services/execdb"
+)
+
+// BlockRewards returns block rewards matching the supplied filter.
+func (s *Service) BlockRewards(ctx context.Context, filter *execdb.BlockRewardFilter) ([]*execdb.BlockReward, error) {
+	tx := s.tx(ctx)
+	if tx == nil {
+		ctx, cancel, err := s.BeginTx(ctx)
+		if err != nil {
+			return nil, errors.Wrap(err, "failed to begin transaction")
+		}
+		tx = s.tx(ctx)
+		defer cancel()
+	}
+
+	// Build the query.
+	queryBuilder := strings.Builder{}
+	queryVals := make([]interface{}, 0)
+
+	queryBuilder.WriteString(`
+SELECT f_block_height
+      ,f_block_hash
+      ,f_fees
+      ,f_payments
+FROM t_block_rewards`)
+
+	conditions := make([]string, 0)
+
+	if filter.From != nil {
+		queryVals = append(queryVals, *filter.From)
+		conditions = append(conditions, fmt.Sprintf("f_block_height >= $%d", len(queryVals)))
+	}
+
+	if filter.To != nil {
+		queryVals = append(queryVals, *filter.To)
+		conditions = append(conditions, fmt.Sprintf("f_block_height <= $%d", len(queryVals)))
+	}
+
+	if filter.TimestampFrom != nil || filter.TimestampTo != nil {
+		queryBuilder.WriteString(`
+LEFT JOIN t_blocks ON t_blocks.f_hash = t_block_rewards.f_block_hash`)
+	}
+
+	if filter.TimestampFrom != nil {
+		queryVals = append(queryVals, *filter.TimestampFrom)
+		conditions = append(conditions, fmt.Sprintf("f_timestamp >= $%d", len(queryVals)))
+	}
+
+	if filter.TimestampTo != nil {
+		queryVals = append(queryVals, *filter.TimestampTo)
+		conditions = append(conditions, fmt.Sprintf("f_timestamp <= $%d", len(queryVals)))
+	}
+
+	if len(conditions) > 0 {
+		queryBuilder.WriteString("\nWHERE ")
+		queryBuilder.WriteString(strings.Join(conditions, "\n  AND "))
+	}
+
+	switch filter.Order {
+	case execdb.OrderEarliest:
+		queryBuilder.WriteString(`
+ORDER BY f_height`)
+	case execdb.OrderLatest:
+		queryBuilder.WriteString(`
+ORDER BY f_height DESC`)
+	default:
+		return nil, errors.New("no order specified")
+	}
+
+	if filter.Limit != 0 {
+		queryVals = append(queryVals, filter.Limit)
+		queryBuilder.WriteString(fmt.Sprintf(`
+LIMIT $%d`, len(queryVals)))
+	}
+
+	if e := log.Trace(); e.Enabled() {
+		params := make([]string, len(queryVals))
+		for i := range queryVals {
+			params[i] = fmt.Sprintf("%v", queryVals[i])
+		}
+		log.Trace().Str("query", strings.ReplaceAll(queryBuilder.String(), "\n", " ")).Strs("params", params).Msg("SQL query")
+	}
+
+	rows, err := tx.Query(ctx,
+		queryBuilder.String(),
+		queryVals...,
+	)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	blockRewards := make([]*execdb.BlockReward, 0)
+	for rows.Next() {
+		blockReward := &execdb.BlockReward{}
+		err := rows.Scan(
+			&blockReward.BlockHeight,
+			&blockReward.BlockHash,
+			&blockReward.Fees,
+			&blockReward.Payments,
+		)
+		if err != nil {
+			return nil, errors.Wrap(err, "failed to scan row")
+		}
+		blockRewards = append(blockRewards, blockReward)
+	}
+
+	// Always return in order of height.
+	sort.Slice(blockRewards, func(i int, j int) bool {
+		return blockRewards[i].BlockHeight < blockRewards[j].BlockHeight
+	})
+
+	return blockRewards, nil
+}

services/execdb/service.go

@@ -64,6 +64,12 @@ type BlocksSetter interface {
 	SetBlocks(ctx context.Context, blocks []*Block) error
 }
 
+// BlockRewardsProvider defines functions to provide block reward information.
+type BlockRewardsProvider interface {
+	// BlockRewards returns block rewards matching the supplied filter.
+	BlockRewards(ctx context.Context, filter *BlockRewardFilter) ([]*BlockReward, error)
+}
+
 // BlockRewardsSetter defines functions to create and update block rewards.
 type BlockRewardsSetter interface {
 	Service