backend_accounts.go

package backend

import (
	"context"

	execproto "github.com/onflow/flow/protobuf/go/flow/execution"
	"google.golang.org/grpc/codes"
	"google.golang.org/grpc/status"

	"github.com/onflow/flow-go/engine/common/rpc/convert"
	"github.com/onflow/flow-go/model/flow"
	"github.com/onflow/flow-go/state/protocol"
	"github.com/onflow/flow-go/storage"
)

type backendAccounts struct {
	state        protocol.State
	executionRPC execproto.ExecutionAPIClient
	headers      storage.Headers
}

func (b *backendAccounts) GetAccount(ctx context.Context, address flow.Address) (*flow.Account, error) {
	return b.GetAccountAtLatestBlock(ctx, address)
}

func (b *backendAccounts) GetAccountAtLatestBlock(ctx context.Context, address flow.Address) (*flow.Account, error) {

	// get the latest sealed header
	latestHeader, err := b.state.Sealed().Head()
	if err != nil {
		return nil, status.Errorf(codes.Internal, "failed to get latest sealed header: %v", err)
	}

	// get the block id of the latest sealed header
	latestBlockID := latestHeader.ID()

	account, err := b.getAccountAtBlockID(ctx, address, latestBlockID)
	if err != nil {
		return nil, err
	}

	return account, nil
}

func (b *backendAccounts) GetAccountAtBlockHeight(
	ctx context.Context,
	address flow.Address,
	height uint64,
) (*flow.Account, error) {
	// get header at given height
	header, err := b.headers.ByHeight(height)
	if err != nil {
		err = convertStorageError(err)
		return nil, err
	}

	// get block ID of the header at the given height
	blockID := header.ID()

	account, err := b.getAccountAtBlockID(ctx, address, blockID)
	if err != nil {
		return nil, err
	}

	return account, nil
}

func (b *backendAccounts) getAccountAtBlockID(
	ctx context.Context,
	address flow.Address,
	blockID flow.Identifier,
) (*flow.Account, error) {

	exeReq := execproto.GetAccountAtBlockIDRequest{
		Address: address.Bytes(),
		BlockId: blockID[:],
	}

	exeRes, err := b.executionRPC.GetAccountAtBlockID(ctx, &exeReq)
	if err != nil {
		errStatus, _ := status.FromError(err)
		if errStatus.Code() == codes.NotFound {
			return nil, err
		}

		return nil, status.Errorf(codes.Internal, "failed to get account from the execution node: %v", err)
	}

	account, err := convert.MessageToAccount(exeRes.GetAccount())
	if err != nil {
		return nil, status.Errorf(codes.Internal, "failed to convert account message: %v", err)
	}

	return account, nil
}