Add apitypes to avoid parsing from/to DB

db/historydb/historydb.go

@@ -150,6 +150,15 @@ func (hdb *HistoryDB) addBatches(d meddler.DB, batches []common.Batch) error {
 	return nil
 }
 
+// GetBatch return the batch with the given batchNum
+func (hdb *HistoryDB) GetBatch(batchNum common.BatchNum) (HistoryBatch, error) {
+	var batch *common.Batch
+	return batch, meddler.QueryRow(
+		hdb.db, &batch,
+		"SELECT * FROM batch WHERE batch_num == $1;", batchNum,
+	)
+}
+
 // GetBatches retrieve batches from the DB, given a range of batch numbers defined by from and to
 func (hdb *HistoryDB) GetBatches(from, to common.BatchNum) ([]common.Batch, error) {
 	var batches []*common.Batch

db/historydb/views.go

@@ -6,6 +6,7 @@ import (
 
 	ethCommon "github.com/ethereum/go-ethereum/common"
 	"github.com/hermeznetwork/hermez-node/common"
+	"github.com/hermeznetwork/hermez-node/db"
 	"github.com/iden3/go-iden3-crypto/babyjub"
 	"github.com/iden3/go-merkletree"
 )
@@ -131,3 +132,24 @@ type HistoryCoordinator struct {
 	FirstItem   int               `meddler:"first_item"`
 	LastItem    int               `meddler:"last_item"`
 }
+
+// HistoryBatch is a representation of a batch with additional information
+// required by the API, and extracted by joining block table
+type HistoryBatch struct {
+	ItemID        int                             `json:"itemId" meddler:"item_id"`
+	BatchNum      common.BatchNum                 `json:"batchNum" meddler:"batch_num"`
+	EthBlockNum   int64                           `json:"ethereumBlockNum" meddler:"eth_block_num"`
+	EthBlockHash  ethCommon.Hash                  `json:"ethereumBlockHash" meddler:"hash"`
+	Timestamp     time.Time                       `json:"timestamp" meddler:"timestamp,utctime"`
+	ForgerAddr    ethCommon.Address               `json:"forgerAddr" meddler:"forger_addr"`
+	CollectedFees map[common.TokenID]db.BigIntStr `json:"collectedFees" meddler:"fees_collected,json"`
+	TotalFeesUSD  float64                         `json:"historicTotalCollectedFeesUSD" meddler:"total_fees_usd"`
+	StateRoot     db.BigIntStr                    `json:"stateRoot" meddler:"state_root"`
+	NumAccounts   int                             `json:"numAccounts" meddler:"num_accounts"`
+	ExitRoot      db.BigIntStr                    `json:"exitRoot" meddler:"exit_root"`
+	ForgeL1TxsNum *int64                          `json:"forgeL1TransactionsNum" meddler:"forge_l1_txs_num"`
+	SlotNum       int64                           `json:"slotNum" meddler:"slot_num"`
+	TotalItems    int                             `json:"-" meddler:"total_items"`
+	FirstItem     int                             `json:"-" meddler:"first_item"`
+	LastItem      int                             `json:"-" meddler:"last_item"`
+}

db/migrations/0001.sql

@@ -16,7 +16,8 @@ CREATE TABLE coordinator (
 );
 
 CREATE TABLE batch (
-    batch_num BIGINT PRIMARY KEY,
+    item_id SERIAL PRIMARY KEY,
+    batch_num BIGINT NOT NULL,
     eth_block_num BIGINT NOT NULL REFERENCES block (eth_block_num) ON DELETE CASCADE,
     forger_addr BYTEA NOT NULL, -- fake foreign key for coordinator
     fees_collected BYTEA NOT NULL,

db/utils.go

@@ -192,3 +192,11 @@ type Paginationer interface {
 	GetPagination() *Pagination
 	Len() int
 }
+
+// BigIntStr is used to Marshal *big.Int directly into strings
+type BigIntStr big.Int
+
+func (b BigIntStr) MarshalText() ([]byte, error) {
+	bigInt := big.Int(b)
+	return []byte((&bigInt).String()), nil
+}