sc_chain_spec/
genesis_block.rs1use std::{marker::PhantomData, sync::Arc};
22
23use codec::Encode;
24use sc_client_api::{backend::Backend, BlockImportOperation};
25use sc_executor::RuntimeVersionOf;
26use sp_core::storage::{well_known_keys, StateVersion, Storage};
27use sp_runtime::{
28 traits::{Block as BlockT, Hash as HashT, HashingFor, Header as HeaderT, Zero},
29 BuildStorage,
30};
31
32pub fn resolve_state_version_from_wasm<E, H>(
34 storage: &Storage,
35 executor: &E,
36) -> sp_blockchain::Result<StateVersion>
37where
38 E: RuntimeVersionOf,
39 H: HashT,
40{
41 if let Some(wasm) = storage.top.get(well_known_keys::CODE) {
42 let mut ext = sp_state_machine::BasicExternalities::new_empty(); let code_fetcher = sp_core::traits::WrappedRuntimeCode(wasm.as_slice().into());
45 let runtime_code = sp_core::traits::RuntimeCode {
46 code_fetcher: &code_fetcher,
47 heap_pages: None,
48 hash: <H as HashT>::hash(wasm).encode(),
49 };
50 let runtime_version = RuntimeVersionOf::runtime_version(executor, &mut ext, &runtime_code)
51 .map_err(|e| sp_blockchain::Error::VersionInvalid(e.to_string()))?;
52 Ok(runtime_version.state_version())
53 } else {
54 Err(sp_blockchain::Error::VersionInvalid(
55 "Runtime missing from initial storage, could not read state version.".to_string(),
56 ))
57 }
58}
59
60pub fn construct_genesis_block<Block: BlockT>(
62 state_root: Block::Hash,
63 state_version: StateVersion,
64) -> Block {
65 let extrinsics_root = <<<Block as BlockT>::Header as HeaderT>::Hashing as HashT>::trie_root(
66 Vec::new(),
67 state_version,
68 );
69
70 Block::new(
71 <<Block as BlockT>::Header as HeaderT>::new(
72 Zero::zero(),
73 extrinsics_root,
74 state_root,
75 Default::default(),
76 Default::default(),
77 ),
78 Default::default(),
79 )
80}
81
82pub trait BuildGenesisBlock<Block: BlockT> {
84 type BlockImportOperation;
86
87 fn build_genesis_block(self) -> sp_blockchain::Result<(Block, Self::BlockImportOperation)>;
90}
91
92pub struct GenesisBlockBuilder<Block: BlockT, B, E> {
94 genesis_storage: Storage,
95 commit_genesis_state: bool,
96 backend: Arc<B>,
97 executor: E,
98 _phantom: PhantomData<Block>,
99}
100
101impl<Block: BlockT, B: Backend<Block>, E: RuntimeVersionOf> GenesisBlockBuilder<Block, B, E> {
102 pub fn new(
104 build_genesis_storage: &dyn BuildStorage,
105 commit_genesis_state: bool,
106 backend: Arc<B>,
107 executor: E,
108 ) -> sp_blockchain::Result<Self> {
109 let genesis_storage =
110 build_genesis_storage.build_storage().map_err(sp_blockchain::Error::Storage)?;
111 Self::new_with_storage(genesis_storage, commit_genesis_state, backend, executor)
112 }
113
114 pub fn new_with_storage(
116 genesis_storage: Storage,
117 commit_genesis_state: bool,
118 backend: Arc<B>,
119 executor: E,
120 ) -> sp_blockchain::Result<Self> {
121 Ok(Self {
122 genesis_storage,
123 commit_genesis_state,
124 backend,
125 executor,
126 _phantom: PhantomData::<Block>,
127 })
128 }
129}
130
131impl<Block: BlockT, B: Backend<Block>, E: RuntimeVersionOf> BuildGenesisBlock<Block>
132 for GenesisBlockBuilder<Block, B, E>
133{
134 type BlockImportOperation = <B as Backend<Block>>::BlockImportOperation;
135
136 fn build_genesis_block(self) -> sp_blockchain::Result<(Block, Self::BlockImportOperation)> {
137 let Self { genesis_storage, commit_genesis_state, backend, executor, _phantom } = self;
138
139 let genesis_state_version =
140 resolve_state_version_from_wasm::<_, HashingFor<Block>>(&genesis_storage, &executor)?;
141 let mut op = backend.begin_operation()?;
142 let state_root =
143 op.set_genesis_state(genesis_storage, commit_genesis_state, genesis_state_version)?;
144 let genesis_block = construct_genesis_block::<Block>(state_root, genesis_state_version);
145
146 Ok((genesis_block, op))
147 }
148}