feat: Add memo field to transaction API

src/lib/mina.ts

@@ -65,7 +65,7 @@ function setCurrentTransaction(transaction: CurrentTransaction) {
 
 type SenderSpec =
   | PrivateKey
-  | { feePayerKey: PrivateKey; fee?: number | string | UInt64 }
+  | { feePayerKey: PrivateKey; fee?: number | string | UInt64; memo?: string }
   | undefined;
 
 function createUnsignedTransaction(
@@ -76,10 +76,7 @@ function createUnsignedTransaction(
 }
 
 function createTransaction(
-  feePayer:
-    | PrivateKey
-    | { feePayerKey: PrivateKey; fee?: number | string | UInt64 }
-    | undefined,
+  feePayer: SenderSpec,
   f: () => unknown,
   { fetchMode = 'cached' as FetchMode } = {}
 ): Transaction {
@@ -89,6 +86,7 @@ function createTransaction(
   let feePayerKey =
     feePayer instanceof PrivateKey ? feePayer : feePayer?.feePayerKey;
   let fee = feePayer instanceof PrivateKey ? undefined : feePayer?.fee;
+  let memo = feePayer instanceof PrivateKey ? '' : feePayer?.memo ?? '';
 
   currentTransaction = {
     sender: feePayerKey,
@@ -127,6 +125,7 @@ function createTransaction(
   let transaction: Parties = {
     otherParties: currentTransaction.parties,
     feePayer: feePayerParty,
+    memo,
   };
 
   nextTransactionId.value += 1;

src/lib/party.ts

@@ -744,10 +744,12 @@ class Party {
 type Parties = {
   feePayer: FeePayerUnsigned;
   otherParties: Party[];
+  memo: string;
 };
 type PartiesSigned = {
   feePayer: FeePayer;
   otherParties: (Party & { authorization: Control | LazyProof })[];
+  memo: string;
 };
 
 // TODO: probably shouldn't hard-code dummy signature
@@ -771,15 +773,16 @@ function toPartyUnsafe({ body, authorization }: Party): Types.Party {
 function toPartiesUnsafe({
   feePayer,
   otherParties,
+  memo,
 }: {
   feePayer: FeePayerUnsigned;
   otherParties: Party[];
+  memo: string;
 }): Types.Parties {
   return {
     feePayer: toFeePayerUnsafe(feePayer),
     otherParties: otherParties.map(toPartyUnsafe),
-    // TODO expose to Mina.transaction
-    memo: Ledger.memoToBase58(''),
+    memo: Ledger.memoToBase58(memo),
   };
 }
 
@@ -842,16 +845,18 @@ function addMissingSignatures(
     party.authorization = { signature };
     return party as P & { authorization: Control };
   }
-  let { feePayer, otherParties } = parties;
+  let { feePayer, otherParties, memo } = parties;
   return {
     feePayer: addFeePayerSignature(feePayer),
     otherParties: otherParties.map((p) => addSignature(p)),
+    memo,
   };
 }
 
 type PartiesProved = {
   feePayer: FeePayerUnsigned;
   otherParties: (Party & { authorization: Control | LazySignature })[];
+  memo: string;
 };
 
 async function addMissingProofs(parties: Parties): Promise<PartiesProved> {
@@ -889,7 +894,7 @@ async function addMissingProofs(parties: Parties): Promise<PartiesProved> {
     party.authorization = { proof: Pickles.proofToString(proof) };
     return party as P & { authorization: Control | LazySignature };
   }
-  let { feePayer, otherParties } = parties;
+  let { feePayer, otherParties, memo } = parties;
   // compute proofs serially. in parallel would clash with our global variable hacks
   let otherPartiesProved: (Party & {
     authorization: Control | LazySignature;
@@ -898,7 +903,7 @@ async function addMissingProofs(parties: Parties): Promise<PartiesProved> {
     let partyProved = await addProof(otherParties[i], i);
     otherPartiesProved.push(partyProved);
   }
-  return { feePayer, otherParties: otherPartiesProved };
+  return { feePayer, otherParties: otherPartiesProved, memo };
 }
 
 /**

src/lib/zkapp.ts

@@ -656,6 +656,7 @@ async function deploy<S extends typeof SmartContract>(
     feePayerKey,
     transactionFee,
     feePayerNonce,
+    memo,
   }: {
     zkappKey: PrivateKey;
     verificationKey: { data: string; hash: string | Field };
@@ -664,6 +665,7 @@ async function deploy<S extends typeof SmartContract>(
     shouldSignFeePayer?: boolean;
     transactionFee?: string | number;
     feePayerNonce?: string | number;
+    memo?: string;
   }
 ) {
   let address = zkappKey.toPublicKey();
@@ -698,6 +700,7 @@ async function deploy<S extends typeof SmartContract>(
       zkapp.self.balance.addInPlace(amount);
     }
   });
+  tx.transaction.memo = memo ?? '';
   if (shouldSignFeePayer) {
     if (feePayerKey === undefined || transactionFee === undefined) {
       throw Error(
@@ -767,11 +770,12 @@ async function callUnproved<S extends typeof SmartContract>(
 }
 
 function addFeePayer(
-  { feePayer, otherParties }: Parties,
+  { feePayer, otherParties, memo }: Parties,
   feePayerKey: PrivateKey | string,
   {
     transactionFee = 0 as number | string,
     feePayerNonce = undefined as number | string | undefined,
+    memo: feePayerMemo = undefined as string | undefined,
   }
 ) {
   feePayer = cloneCircuitValue(feePayer);
@@ -782,11 +786,17 @@ function addFeePayer(
     let senderAccount = Mina.getAccount(senderAddress);
     feePayerNonce = senderAccount.nonce.toString();
   }
+  let newMemo = '';
+  if (feePayerMemo) {
+    newMemo = Ledger.memoToBase58(feePayerMemo);
+  } else {
+    newMemo = memo;
+  }
   feePayer.body.nonce = UInt32.fromString(`${feePayerNonce}`);
   feePayer.body.publicKey = senderAddress;
   feePayer.body.fee = UInt64.fromString(`${transactionFee}`);
   Party.signFeePayerInPlace(feePayer, feePayerKey);
-  return { feePayer, otherParties };
+  return { feePayer, otherParties, memo: newMemo };
 }
 
 function signFeePayer(
@@ -795,7 +805,7 @@ function signFeePayer(
   {
     transactionFee = 0 as number | string,
     feePayerNonce = undefined as number | string | undefined,
-    memo = '',
+    memo: feePayerMemo = undefined as string | undefined,
   }
 ) {
   let parties: Types.Json.Parties = JSON.parse(transactionJson);
@@ -806,10 +816,10 @@ function signFeePayer(
     let senderAccount = Mina.getAccount(senderAddress);
     feePayerNonce = senderAccount.nonce.toString();
   }
+  if (feePayerMemo) parties.memo = Ledger.memoToBase58(feePayerMemo);
   parties.feePayer.body.nonce = `${feePayerNonce}`;
   parties.feePayer.body.publicKey = Ledger.publicKeyToString(senderAddress);
   parties.feePayer.body.fee = `${transactionFee}`;
-  parties.memo = Ledger.memoToBase58(memo);
   return signJsonTransaction(JSON.stringify(parties), feePayerKey);
 }