github.com/stafiprotocol/go-substrate-rpc-client@v1.4.7/rpc/chain/get_block_hash.go (about)

     1  // Go Substrate RPC Client (GSRPC) provides APIs and types around Polkadot and any Substrate-based chain RPC calls
     2  //
     3  // Copyright 2020 Stafi Protocol
     4  //
     5  // Licensed under the Apache License, Version 2.0 (the "License");
     6  // you may not use this file except in compliance with the License.
     7  // You may obtain a copy of the License at
     8  //
     9  //     http://www.apache.org/licenses/LICENSE-2.0
    10  //
    11  // Unless required by applicable law or agreed to in writing, software
    12  // distributed under the License is distributed on an "AS IS" BASIS,
    13  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    14  // See the License for the specific language governing permissions and
    15  // limitations under the License.
    16  
    17  package chain
    18  
    19  import (
    20  	"github.com/stafiprotocol/go-substrate-rpc-client/types"
    21  )
    22  
    23  // GetBlockHash returns the block hash for a specific block height
    24  func (c *Chain) GetBlockHash(blockNumber uint64) (types.Hash, error) {
    25  	return c.getBlockHash(&blockNumber)
    26  }
    27  
    28  // GetBlockHashLatest returns the latest block hash
    29  func (c *Chain) GetBlockHashLatest() (types.Hash, error) {
    30  	return c.getBlockHash(nil)
    31  }
    32  
    33  func (c *Chain) getBlockHash(blockNumber *uint64) (types.Hash, error) {
    34  	var res string
    35  	var err error
    36  
    37  	if blockNumber == nil {
    38  		err = c.client.Call(&res, "chain_getBlockHash")
    39  	} else {
    40  		err = c.client.Call(&res, "chain_getBlockHash", *blockNumber)
    41  	}
    42  
    43  	if err != nil {
    44  		return types.Hash{}, err
    45  	}
    46  
    47  	return types.NewHashFromHexString(res)
    48  }