区块Header在db中存储
key：h + number(区块高度) + block hash(区块hash)
value：Header
1.hash和number得到key
go-ethereum/core/rawdb/schema.go
//h + number + block hash
// headerKey = headerPrefix + num (uint64 big endian) + hash
func headerKey(number uint64, hash common.Hash) []byte {
return append(append(headerPrefix, encodeBlockNumber(number)...), hash.Bytes()...)
}
2.通过block hash和block number得到Header
go-ethereum/core/rawdb/accessors_chain.go
// ReadHeader retrieves the block header corresponding to the hash.
func ReadHeader(db DatabaseReader, hash common.Hash, number uint64) *types.Header {
data := ReadHeaderRLP(db, hash, number) //通过hash和number得到key，再通过key去db读取data
if len(data) == 0 {
return nil
}
header := new(types.Header)
if err := rlp.Decode(bytes.NewReader(data), header); err != nil { //data解析成Header
log.Error("Invalid block header RLP", "hash", hash, "err", err)
return nil
}
return header
}
