op-chain-ops: tx-builder safe types

Implement the types for working with the Safe
tx-builder application. These types should be able
to be round trip serialized into JSON. These types
will be used to create Safe tx-builder bundles
that can be dropped into the UI or can be combined
with additional tooling to send the transactions
to the Safe backend directly or directly interact
with the safe contracts.

op-chain-ops/safe/batch_file.go

+// Package safe contains types for working with Safe smart contract wallets. These are used to
+// build batch transactions for the tx-builder app. The types are based on
+// https://github.com/safe-global/safe-react-apps/blob/development/apps/tx-builder/src/typings/models.ts.
+package safe
+
+import (
+	"encoding/json"
+	"fmt"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/hexutil"
+	"math/big"
+)
+
+// BatchFile represents a Safe tx-builder transaction.
+type BatchFile struct {
+	Version      string             `json:"version"`
+	ChainID      *big.Int           `json:"chainId"`
+	CreatedAt    uint64             `json:"createdAt"`
+	Meta         BatchFileMeta      `json:"meta"`
+	Transactions []BatchTransaction `json:"transactions"`
+}
+
+// bathcFileMarshaling is a helper type used for JSON marshaling.
+type batchFileMarshaling struct {
+	Version      string             `json:"version"`
+	ChainID      string             `json:"chainId"`
+	CreatedAt    uint64             `json:"createdAt"`
+	Meta         BatchFileMeta      `json:"meta"`
+	Transactions []BatchTransaction `json:"transactions"`
+}
+
+// MarshalJSON will marshal a BatchFile to JSON.
+func (b *BatchFile) MarshalJSON() ([]byte, error) {
+	return json.Marshal(batchFileMarshaling{
+		Version:      b.Version,
+		ChainID:      b.ChainID.String(),
+		CreatedAt:    b.CreatedAt,
+		Meta:         b.Meta,
+		Transactions: b.Transactions,
+	})
+}
+
+// UnmarshalJSON will unmarshal a BatchFile from JSON.
+func (b *BatchFile) UnmarshalJSON(data []byte) error {
+	var bf batchFileMarshaling
+	if err := json.Unmarshal(data, &bf); err != nil {
+		return err
+	}
+	b.Version = bf.Version
+	chainId, ok := new(big.Int).SetString(bf.ChainID, 10)
+	if !ok {
+		return fmt.Errorf("cannot set chainId to %s", bf.ChainID)
+	}
+	b.ChainID = chainId
+	b.CreatedAt = bf.CreatedAt
+	b.Meta = bf.Meta
+	b.Transactions = bf.Transactions
+	return nil
+}
+
+// BatchFileMeta contains metadata about a BatchFile. Not all
+// of the fields are required.
+type BatchFileMeta struct {
+	TxBuilderVersion        string `json:"txBuilderVersion,omitempty"`
+	Checksum                string `json:"checksum,omitempty"`
+	CreatedFromSafeAddress  string `json:"createdFromSafeAddress"`
+	CreatedFromOwnerAddress string `json:"createdFromOwnerAddress"`
+	Name                    string `json:"name"`
+	Description             string `json:"description"`
+}
+
+// BatchTransaction represents a single call in a tx-builder transaction.
+type BatchTransaction struct {
+	To          common.Address    `json:"to"`
+	Value       *big.Int          `json:"value"`
+	Data        []byte            `json:"data"`
+	Method      ContractMethod    `json:"contractMethod"`
+	InputValues map[string]string `json:"contractInputsValues"`
+}
+
+// UnmarshalJSON will unmarshal a BatchTransaction from JSON.
+func (b *BatchTransaction) UnmarshalJSON(data []byte) error {
+	var bt batchTransactionMarshaling
+	if err := json.Unmarshal(data, &bt); err != nil {
+		return err
+	}
+	b.To = common.HexToAddress(bt.To)
+	b.Value = new(big.Int).SetUint64(bt.Value)
+	b.Method = bt.Method
+	b.InputValues = bt.InputValues
+	return nil
+}
+
+// MarshalJSON will marshal a BatchTransaction to JSON.
+func (b *BatchTransaction) MarshalJSON() ([]byte, error) {
+	batch := batchTransactionMarshaling{
+		To:          b.To.Hex(),
+		Value:       b.Value.Uint64(),
+		Method:      b.Method,
+		InputValues: b.InputValues,
+	}
+	if len(b.Data) != 0 {
+		hex := hexutil.Encode(b.Data)
+		batch.Data = &hex
+	}
+	return json.Marshal(batch)
+}
+
+// batchTransactionMarshaling is a helper type used for JSON marshaling.
+type batchTransactionMarshaling struct {
+	To          string            `json:"to"`
+	Value       uint64            `json:"value,string"`
+	Data        *string           `json:"data"`
+	Method      ContractMethod    `json:"contractMethod"`
+	InputValues map[string]string `json:"contractInputsValues"`
+}
+
+// ContractMethod represents a method call in a tx-builder transaction.
+type ContractMethod struct {
+	Inputs  []ContractInput `json:"inputs"`
+	Name    string          `json:"name"`
+	Payable bool            `json:"payable"`
+}
+
+// ContractInput represents an input to a contract method.
+type ContractInput struct {
+	InternalType string          `json:"internalType"`
+	Name         string          `json:"name"`
+	Type         string          `json:"type"`
+	Components   []ContractInput `json:"components,omitempty"`
+}

op-chain-ops/safe/batch_file_test.go

+package safe
+
+import (
+	"bytes"
+	"encoding/json"
+	"os"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestBatchFileJSONPrepareBedrock(t *testing.T) {
+	testBatchFileJSON(t, "testdata/batch-prepare-bedrock.json")
+}
+
+func TestBatchFileJSONL2OO(t *testing.T) {
+	testBatchFileJSON(t, "testdata/l2-output-oracle.json")
+}
+
+func testBatchFileJSON(t *testing.T, path string) {
+	b, err := os.ReadFile(path)
+	require.NoError(t, err)
+	dec := json.NewDecoder(bytes.NewReader(b))
+	decoded := new(BatchFile)
+	require.NoError(t, dec.Decode(decoded))
+	data, err := json.Marshal(decoded)
+	require.NoError(t, err)
+	require.JSONEq(t, string(b), string(data))
+}

op-chain-ops/safe/testdata/batch-prepare-bedrock.json

+{"version":"1.0","chainId":"1","createdAt":1683299982633,"meta":{"name":"Transactions Batch","description":"","txBuilderVersion":"1.13.3","createdFromSafeAddress":"0xAB23dE0DbE0aedF356af3F815c8B47D88575D82d","createdFromOwnerAddress":"","checksum":"0x3be12fb2a12e07f516c3895194f8418c6640f27fb3324e4dc06dce337b7ae7c3"},"transactions":[{"to":"0x09AA72510eE2e1c705Dc4e2114b025a12E116bb8","value":"0","data":null,"contractMethod":{"inputs":[{"internalType":"address","name":"newOwner","type":"address"}],"name":"transferOwnership","payable":false},"contractInputsValues":{"newOwner":"0x3C0dD22068a69433938097ad335Cb44a9DBf5c1A"}},{"to":"0x20835fbB5Dcb9B9c3074C0780bB07790a7525f41","value":"0","data":null,"contractMethod":{"inputs":[{"internalType":"address","name":"newOwner","type":"address"}],"name":"transferOwnership","payable":false},"contractInputsValues":{"newOwner":"0x3C0dD22068a69433938097ad335Cb44a9DBf5c1A"}},{"to":"0xcAC4CDD0C2D87e65710C87dE3955974d6a0b6940","value":"0","data":null,"contractMethod":{"inputs":[{"internalType":"address","name":"_owner","type":"address"}],"name":"setOwner","payable":false},"contractInputsValues":{"_owner":"0x3C0dD22068a69433938097ad335Cb44a9DBf5c1A"}},{"to":"0xE1229AbA7DC7e74C9995254bbaa40bedDB0B8B4d","value":"0","data":null,"contractMethod":{"inputs":[{"internalType":"address","name":"_admin","type":"address"}],"name":"changeAdmin","payable":false},"contractInputsValues":{"_admin":"0x3C0dD22068a69433938097ad335Cb44a9DBf5c1A"}}]}
\ No newline at end of file

op-chain-ops/safe/testdata/l2-output-oracle.json

+{"version":"1.0","chainId":"1","createdAt":1691808995527,"meta":{"name":"Transactions Batch","description":"","txBuilderVersion":"1.16.1","createdFromSafeAddress":"0xc9D26D376dD75573E0C3247C141881F053d27Ae8","createdFromOwnerAddress":"","checksum":"0x2a88db9ce20d2eb5a80910842e9e94d5870497af45986a6c1c7e2c91d15e34f0"},"transactions":[{"to":"0xE5FF3b57695079f808a24256734483CD3889fA9E","value":"0","data":null,"contractMethod":{"inputs":[{"internalType":"bytes32","name":"_outputRoot","type":"bytes32"},{"internalType":"uint256","name":"_l2BlockNumber","type":"uint256"},{"internalType":"bytes32","name":"_l1BlockHash","type":"bytes32"},{"internalType":"uint256","name":"_l1BlockNumber","type":"uint256"}],"name":"proposeL2Output","payable":true},"contractInputsValues":{"_outputRoot":"0x5398552529cbd710f485e297bcf15233b8475bdad43280c99334f65a1d4278ff","_l2BlockNumber":"0","_l1BlockHash":"0x01f814a4547c01c18c0eb8b96cff19bc5dc83b1d2d8a8bbb03206587f594c80a","_l1BlockNumber":"1"}},{"to":"0xE5FF3b57695079f808a24256734483CD3889fA9E","value":"0","data":null,"contractMethod":{"inputs":[{"internalType":"uint256","name":"_l2OutputIndex","type":"uint256"}],"name":"deleteL2Outputs","payable":false},"contractInputsValues":{"_l2OutputIndex":"2"}}]}
\ No newline at end of file