Merge pull request #157 from ethcore/db

Indexed/hashed chain blocks

chain/src/block.rs

@@ -64,6 +64,10 @@ impl Block {
 	pub fn header(&self) -> &BlockHeader {
 		&self.block_header
 	}
+
+	pub fn drain(self) -> (BlockHeader, Vec<Transaction>) {
+		(self.block_header, self.transactions)
+	}
 }
 
 #[cfg(test)]

db/src/indexed_block.rs

@@ -0,0 +1,77 @@
+use chain;
+use primitives::hash::H256;
+
+pub struct IndexedBlock {
+	header: chain::BlockHeader,
+	header_hash: H256,
+	transactions: Vec<chain::Transaction>,
+	// guaranteed to be the same length as transactions
+	transaction_hashes: Vec<H256>,
+}
+
+impl From<chain::Block> for IndexedBlock {
+	fn from(block: chain::Block) -> Self {
+		let (org_header, org_txs) = block.drain();
+		let mut hashes = Vec::with_capacity(org_txs.len());
+		for tx in org_txs.iter() {
+			hashes.push(tx.hash())
+		}
+		let header_hash = org_header.hash();
+
+		IndexedBlock {
+			header: org_header,
+			header_hash: header_hash,
+			transactions: org_txs,
+			transaction_hashes: hashes,
+		}
+	}
+}
+
+impl IndexedBlock {
+	pub fn transactions(&self) -> IndexedTransactions {
+		IndexedTransactions {
+			position: 0,
+			block: self,
+		}
+	}
+
+	pub fn header(&self) -> &chain::BlockHeader {
+		&self.header
+	}
+
+	pub fn hash(&self) -> &H256 {
+		&self.header_hash
+	}
+}
+
+pub struct IndexedTransactions<'a> {
+	position: usize,
+	block: &'a IndexedBlock,
+}
+
+impl<'a> Iterator for IndexedTransactions<'a> {
+	type Item = (&'a H256, &'a chain::Transaction);
+
+	fn next(&mut self) -> Option<(&'a H256, &'a chain::Transaction)> {
+		if self.position >= self.block.transactions.len() {
+			None
+		}
+		else {
+			Some((&self.block.transaction_hashes[self.position], &self.block.transactions[self.position]))
+		}
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use test_data;
+	use super::IndexedBlock;
+
+	#[test]
+	fn index() {
+		let block = test_data::block_h1();
+		let indexed_block: IndexedBlock = block.clone().into();
+
+		assert_eq!(*indexed_block.transactions().nth(0).unwrap().0, block.transactions()[0].hash());
+	}
+}

db/src/lib.rs

@@ -27,6 +27,7 @@ mod transaction_provider;
 mod transaction_meta_provider;
 mod error;
 mod update_context;
+mod indexed_block;
 
 pub enum BlockRef {
 	Number(u32),
@@ -49,6 +50,7 @@ pub use transaction_provider::TransactionProvider;
 pub use transaction_meta_provider::TransactionMetaProvider;
 pub use block_stapler::{BlockStapler, BlockInsertedChain};
 pub use block_provider::BlockProvider;
+pub use indexed_block::{IndexedBlock, IndexedTransactions};
 
 #[cfg(feature="dev")]
 pub use test_storage::TestStorage;