Add SigningCosmosClient.appendSignature

CHANGELOG.md

@@ -22,6 +22,8 @@
   remove such functionality from `CosmosClient.searchTx`.
 - @cosmjs/launchpad: Add `SigningCosmosClient.sign` method for signing without
   broadcasting.
+- @cosmjs/launchpad: Add `SigningCosmosClient.appendSignature` method creating
+  transactions with multiple signatures.
 - @cosmjs/launchpad: Add support for undefined memo in `makeSignDoc`.
 - @cosmjs/launchpad-ledger: `LedgerSigner.sign` method renamed `signAmino`.
 - @cosmjs/proto-signing: Add new package for handling transaction signing with

packages/launchpad/src/signingcosmosclient.spec.ts

@@ -14,6 +14,7 @@ import {
   makeRandomAddress,
   pendingWithoutLaunchpad,
 } from "./testutils.spec";
+import { makeCosmoshubPath } from "./wallet";
 
 describe("SigningCosmosClient", () => {
   describe("makeReadOnly", () => {
@@ -222,4 +223,65 @@ describe("SigningCosmosClient", () => {
       assertIsBroadcastTxSuccess(broadcastResult);
     });
   });
+
+  describe("appendSignature", () => {
+    it("works", async () => {
+      pendingWithoutLaunchpad();
+      const wallet0 = await Secp256k1HdWallet.fromMnemonic(faucet.mnemonic, makeCosmoshubPath(0));
+      const wallet1 = await Secp256k1HdWallet.fromMnemonic(faucet.mnemonic, makeCosmoshubPath(1));
+      const client0 = new SigningCosmosClient(launchpad.endpoint, faucet.address0, wallet0);
+      const client1 = new SigningCosmosClient(launchpad.endpoint, faucet.address1, wallet1);
+
+      const msg1: MsgSend = {
+        type: "cosmos-sdk/MsgSend",
+        value: {
+          from_address: faucet.address0,
+          to_address: makeRandomAddress(),
+          amount: coins(1234567, "ucosm"),
+        },
+      };
+      const msg2: MsgSend = {
+        type: "cosmos-sdk/MsgSend",
+        value: {
+          from_address: faucet.address1,
+          to_address: makeRandomAddress(),
+          amount: coins(1234567, "ucosm"),
+        },
+      };
+      const fee = {
+        amount: coins(2000, "ucosm"),
+        gas: "160000", // 2*80k
+      };
+      const memo = "This must be authorized by the two of us";
+
+      const signed = await client0.sign([msg1, msg2], fee, memo);
+      expect(signed.msg).toEqual([msg1, msg2]);
+      expect(signed.fee).toEqual(fee);
+      expect(signed.memo).toEqual(memo);
+      expect(signed.signatures).toEqual([
+        {
+          pub_key: faucet.pubkey0,
+          signature: jasmine.stringMatching(base64Matcher),
+        },
+      ]);
+
+      const cosigned = await client1.appendSignature(signed);
+      expect(cosigned.msg).toEqual([msg1, msg2]);
+      expect(cosigned.fee).toEqual(fee);
+      expect(cosigned.memo).toEqual(memo);
+      expect(cosigned.signatures).toEqual([
+        {
+          pub_key: faucet.pubkey0,
+          signature: jasmine.stringMatching(base64Matcher),
+        },
+        {
+          pub_key: faucet.pubkey1,
+          signature: jasmine.stringMatching(base64Matcher),
+        },
+      ]);
+
+      const broadcastResult = await client0.broadcastTx(cosigned);
+      assertIsBroadcastTxSuccess(broadcastResult);
+    });
+  });
 });

packages/launchpad/src/signingcosmosclient.ts

@@ -1,4 +1,6 @@
 /* eslint-disable @typescript-eslint/naming-convention */
+import equals from "fast-deep-equal";
+
 import { Coin } from "./coins";
 import { Account, BroadcastTxResult, CosmosClient, GetSequenceResult } from "./cosmosclient";
 import { makeSignDoc } from "./encoding";
@@ -102,4 +104,25 @@ export class SigningCosmosClient extends CosmosClient {
     const { signed, signature } = await this.signer.signAmino(this.senderAddress, signDoc);
     return makeStdTx(signed, signature);
   }
+
+  /**
+   * Gets account number and sequence from the API, creates a sign doc,
+   * creates a single signature and appends it to the existing signatures.
+   */
+  public async appendSignature(signedTx: StdTx): Promise<StdTx> {
+    const { msg: msgs, fee, memo } = signedTx;
+    const { accountNumber, sequence } = await this.getSequence();
+    const chainId = await this.getChainId();
+    const signDoc = makeSignDoc(msgs, fee, chainId, memo, accountNumber, sequence);
+    const { signed, signature: additionalSignature } = await this.signer.signAmino(
+      this.senderAddress,
+      signDoc,
+    );
+    if (!equals(signDoc, signed)) {
+      throw new Error(
+        "The signed document differs from the one of the original transaction. This is not allowed since the resulting transaction will be invalid.",
+      );
+    }
+    return makeStdTx(signed, [...signedTx.signatures, additionalSignature]);
+  }
 }

packages/launchpad/src/testutils.spec.ts

@@ -42,6 +42,22 @@ export const faucet = {
     type: "tendermint/PubKeySecp256k1",
     value: "A08EGB7ro1ORuFhjOnZcSgwYlpe0DSFjVNUIkNNQxwKQ",
   },
+  pubkey1: {
+    type: "tendermint/PubKeySecp256k1",
+    value: "AiDosfIbBi54XJ1QjCeApumcy/FjdtF+YhywPf3DKTx7",
+  },
+  pubkey2: {
+    type: "tendermint/PubKeySecp256k1",
+    value: "AzQg33JZqH7vSsm09esZY5bZvmzYwE/SY78cA0iLxpD7",
+  },
+  pubkey3: {
+    type: "tendermint/PubKeySecp256k1",
+    value: "A3gOAlB6aiRTCPvWMQg2+ZbGYNsLd8qlvV28m8p2UhY2",
+  },
+  pubkey4: {
+    type: "tendermint/PubKeySecp256k1",
+    value: "Aum2063ub/ErUnIUB36sK55LktGUStgcbSiaAnL1wadu",
+  },
   address0: "cosmos1pkptre7fdkl6gfrzlesjjvhxhlc3r4gmmk8rs6",
   address1: "cosmos10dyr9899g6t0pelew4nvf4j5c3jcgv0r73qga5",
   address2: "cosmos1xy4yqngt0nlkdcenxymg8tenrghmek4nmqm28k",

packages/launchpad/types/signingcosmosclient.d.ts

@@ -58,4 +58,9 @@ export declare class SigningCosmosClient extends CosmosClient {
    * creates a single signature and assembles the signed transaction.
    */
   sign(msgs: readonly Msg[], fee: StdFee, memo?: string): Promise<StdTx>;
+  /**
+   * Gets account number and sequence from the API, creates a sign doc,
+   * creates a single signature and appends it to the existing signatures.
+   */
+  appendSignature(signedTx: StdTx): Promise<StdTx>;
 }