chore: notes for transaction size

nervosnetwork · Oct 22, 2019 · ea1a93d · ea1a93d
1 parent bf396e5
commit ea1a93d
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Showing 2 changed files with 11 additions and 0 deletions.
diff --git a/packages/neuron-wallet/src/services/cells.ts b/packages/neuron-wallet/src/services/cells.ts
@@ -166,6 +166,10 @@ export default class CellsService {
   }
 
   public static everyInputFee = (feeRate: bigint): bigint => {
+    /*
+    * every input need 44 Bytes and extra 4 Bytes for offset
+    * every input need 1 witness signed by secp256k1, with 65 Bytes data, and serialized in 69 Bytes
+    */
     const ratio = BigInt(1000)
     const base = BigInt(4 + 44 + 69) * feeRate
     const fee = base / ratio

diff --git a/packages/neuron-wallet/src/services/tx/transaction-generator.ts b/packages/neuron-wallet/src/services/tx/transaction-generator.ts
@@ -6,6 +6,13 @@ import { TargetOutput } from './params'
 
 export class TransactionGenerator {
   private static txSerializedSizeInBlockWithoutInputs = (outputLength: number) : number => {
+    /*
+    * add a transaction to block need 4 Bytes for offset
+    * a transaction with empty inputs/outputs/cellDeps/header/outputs_data/witnesses need 68 Bytes
+    * every cellDep need 37 Bytes, transaction in Neuron only one cellDep
+    * every output without typeScript & with lock in secp need 97 Bytes and 4 Bytes for offset (add to transaction)
+    * every outputsData in "0x" need 4 Bytes and 4 Bytes for offset
+    */
     return 4 + 68 + 37 * 1 + (4 + 97 + 4 + 4) * outputLength
   }