From 4250aa214d3d3416c0d0c179b4072b2956c5a726 Mon Sep 17 00:00:00 2001
From: Marcin Zolkiewski <zolkiewski.marcin@gmail.com>
Date: Tue, 7 Jan 2020 23:57:58 +0100
Subject: [PATCH 01/10] basic implementation of send offline

---
 packages/signer-cli/src/cmdSendOffline.ts | 73 +++++++++++++++++++++++
 packages/signer-cli/src/signer.ts         |  4 ++
 2 files changed, 77 insertions(+)
 create mode 100644 packages/signer-cli/src/cmdSendOffline.ts

diff --git a/packages/signer-cli/src/cmdSendOffline.ts b/packages/signer-cli/src/cmdSendOffline.ts
new file mode 100644
index 000000000..5da9ba0d5
--- /dev/null
+++ b/packages/signer-cli/src/cmdSendOffline.ts
@@ -0,0 +1,73 @@
+// Copyright 2018-2020 @polkadot/signer-cli authors & contributors
+// This software may be modified and distributed under the terms
+// of the Apache-2.0 license. See the LICENSE file for details.
+
+import * as readline from "readline";
+import { ApiPromise, WsProvider } from "@polkadot/api";
+import { assert } from "@polkadot/util";
+
+function getSignature(data: any) {
+  const rl = readline.createInterface({
+    input: process.stdin,
+    output: process.stdout
+  });
+
+  return new Promise((resolve): void => {
+    rl.question(`Payload: ${data}\nSignature> `, signature => {
+      resolve(signature);
+      rl.close();
+    });
+  });
+}
+
+export default async function cmdSendOffline(
+  account: string,
+  blocks: number | undefined,
+  endpoint: string,
+  [tx, ...params]: string[]
+): Promise<void> {
+  const provider = new WsProvider(endpoint);
+  const api = await ApiPromise.create({ provider });
+  const [section, method] = tx.split(".");
+
+  assert(api.tx[section] && api.tx[section][method], `Unable to find method ${section}.${method}`);
+
+  const options: any = {};
+  let blockNumber: any;
+
+  if (blocks === 0) {
+    options.era = 0;
+    options.blockHash = api.genesisHash;
+    blockNumber = 0;
+  } else if (blocks != null) {
+    // Get current block if we want to modify the number of blocks we have to sign
+    const signedBlock = await api.rpc.chain.getBlock();
+
+    options.blockHash = signedBlock.block.header.hash;
+    options.era = api.createType("ExtrinsicEra", {
+      current: signedBlock.block.header.number,
+      period: blocks
+    });
+    blockNumber = signedBlock.block.header.number;
+  }
+
+  const transaction: any = api.tx[section][method](...params);
+
+  const payload: any = api.createType("SignerPayload", {
+    version: api.extrinsicVersion,
+    runtimeVersion: api.runtimeVersion,
+    genesisHash: api.genesisHash,
+    ...options,
+    address: account,
+    method: transaction.method,
+    blockNumber
+  });
+
+  const signature = await getSignature(payload.toRaw().data);
+
+  transaction.addSignature(account, signature, payload.toPayload());
+
+  console.log("\nSigned transaction:\n" + transaction.toJSON());
+
+  process.exit(0);
+}
diff --git a/packages/signer-cli/src/signer.ts b/packages/signer-cli/src/signer.ts
index 74b4b22c2..284202625 100644
--- a/packages/signer-cli/src/signer.ts
+++ b/packages/signer-cli/src/signer.ts
@@ -6,6 +6,7 @@ import yargs from 'yargs';
 
 import cmdSign from './cmdSign';
 import cmdSubmit from './cmdSubmit';
+import cmdSendOffline from './cmdSendOffline';
 
 const BLOCKTIME = 6;
 const ONE_MINUTE = 60 / BLOCKTIME;
@@ -57,6 +58,9 @@ async function main (): Promise<void> {
   } else if (command === 'submit') {
     const mortality = minutes != null ? minutes * ONE_MINUTE : blocks;
     return cmdSubmit(account, mortality, ws || '', params);
+  } else if (command === 'sendOffline') {
+    const mortality = minutes != null ? minutes * ONE_MINUTE : blocks;
+    return cmdSendOffline(account, mortality, ws || '', params);
   }
 
   throw new Error(`Unknown command '${command}' found, expected one of 'sign' or 'submit'`);

From ddf5c2f2145b09f2ce0429aad7bf2ad8efff253d Mon Sep 17 00:00:00 2001
From: Marcin Zolkiewski <zolkiewski.marcin@gmail.com>
Date: Thu, 9 Jan 2020 11:45:16 +0100
Subject: [PATCH 02/10] added nonce

---
 packages/signer-cli/src/cmdSendOffline.ts | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/packages/signer-cli/src/cmdSendOffline.ts b/packages/signer-cli/src/cmdSendOffline.ts
index 5da9ba0d5..3b813e837 100644
--- a/packages/signer-cli/src/cmdSendOffline.ts
+++ b/packages/signer-cli/src/cmdSendOffline.ts
@@ -52,6 +52,7 @@ export default async function cmdSendOffline(
   }
 
   const transaction: any = api.tx[section][method](...params);
+  const nonce: any = await api.query.system.accountNonce(account);
 
   const payload: any = api.createType("SignerPayload", {
     version: api.extrinsicVersion,
@@ -60,7 +61,8 @@ export default async function cmdSendOffline(
     ...options,
     address: account,
     method: transaction.method,
-    blockNumber
+    blockNumber,
+    nonce
   });
 
   const signature = await getSignature(payload.toRaw().data);

From 86d9a2424114c6d2e89c3a169918ce895f6c23cb Mon Sep 17 00:00:00 2001
From: Marcin Zolkiewski <zolkiewski.marcin@gmail.com>
Date: Fri, 10 Jan 2020 00:04:01 +0100
Subject: [PATCH 03/10] added yargs docs and fixed typos

---
 packages/signer-cli/src/signer.ts | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/packages/signer-cli/src/signer.ts b/packages/signer-cli/src/signer.ts
index 284202625..4a1423747 100644
--- a/packages/signer-cli/src/signer.ts
+++ b/packages/signer-cli/src/signer.ts
@@ -14,7 +14,8 @@ const ONE_MINUTE = 60 / BLOCKTIME;
 const { _: [command, ...params], account, blocks, minutes, seed, type, ws } = yargs
   .usage('Usage: [options] <endpoint> <...params>')
   .usage('Example: submit --account D3AhD...wrx --ws wss://... balances.transfer F7Gh 10000 ')
-  .usage('Example: sign --seed "..." --account D3AhD...wrx --crypto ed25519 0x123...789')
+  .usage('Example: sign --seed "..." --account D3AhD...wrx --type ed25519 0x123...789')
+  .usage('Example: sendOffline --seed "..." --account D3AhD...wrx --type ed25519 0x123...789')
   .wrap(120)
   .options({
     account: {
@@ -33,12 +34,17 @@ const { _: [command, ...params], account, blocks, minutes, seed, type, ws } = ya
       type: 'string'
     },
     minutes: {
-      description: 'Approximate time for a transction to be signed and submitted before becoming invalid (mortality in minutes)',
+      description: 'Approximate time for a transaction to be signed and submitted before becoming invalid (mortality in minutes)',
       default: undefined as number | undefined,
       type: 'number'
     },
     blocks: {
-      description: 'Exact number of blocks for a transction to be signed and submitted before becoming invalid (mortality in blocks). Set to 0 for an immortal transaction (not recomended)',
+      description: 'Exact number of blocks for a transaction to be signed and submitted before becoming invalid (mortality in blocks). Set to 0 for an immortal transaction (not recomended, but useful for \'sendOffline\' command to ensure the transaction does not expire)',
+      default: undefined as number | undefined,
+      type: 'number'
+    },
+    nonce: {
+      description: 'Transaction nonce (sendOffline only)',
       default: undefined as number | undefined,
       type: 'number'
     },
@@ -63,7 +69,7 @@ async function main (): Promise<void> {
     return cmdSendOffline(account, mortality, ws || '', params);
   }
 
-  throw new Error(`Unknown command '${command}' found, expected one of 'sign' or 'submit'`);
+  throw new Error(`Unknown command '${command}' found, expected one of 'sign', 'submit' or 'sendOffline'`);
 }
 
 main().catch((error): void => {

From 036248e9297b3b3ed5e272b616e960c55bdc364a Mon Sep 17 00:00:00 2001
From: Marcin Zolkiewski <zolkiewski.marcin@gmail.com>
Date: Fri, 10 Jan 2020 00:34:34 +0100
Subject: [PATCH 04/10] passing nonce as positional parameter

---
 packages/signer-cli/src/signer.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/signer-cli/src/signer.ts b/packages/signer-cli/src/signer.ts
index 4a1423747..e1a39c7eb 100644
--- a/packages/signer-cli/src/signer.ts
+++ b/packages/signer-cli/src/signer.ts
@@ -11,7 +11,7 @@ import cmdSendOffline from './cmdSendOffline';
 const BLOCKTIME = 6;
 const ONE_MINUTE = 60 / BLOCKTIME;
 
-const { _: [command, ...params], account, blocks, minutes, seed, type, ws } = yargs
+const { _: [command, ...params], account, blocks, nonce, minutes, seed, type, ws } = yargs
   .usage('Usage: [options] <endpoint> <...params>')
   .usage('Example: submit --account D3AhD...wrx --ws wss://... balances.transfer F7Gh 10000 ')
   .usage('Example: sign --seed "..." --account D3AhD...wrx --type ed25519 0x123...789')
@@ -66,7 +66,7 @@ async function main (): Promise<void> {
     return cmdSubmit(account, mortality, ws || '', params);
   } else if (command === 'sendOffline') {
     const mortality = minutes != null ? minutes * ONE_MINUTE : blocks;
-    return cmdSendOffline(account, mortality, ws || '', params);
+    return cmdSendOffline(account, mortality, ws || '', nonce, params);
   }
 
   throw new Error(`Unknown command '${command}' found, expected one of 'sign', 'submit' or 'sendOffline'`);

From 2bdd9ef7629d9d97b2f0cf2077055306455d39da Mon Sep 17 00:00:00 2001
From: Marcin Zolkiewski <zolkiewski.marcin@gmail.com>
Date: Fri, 10 Jan 2020 00:35:10 +0100
Subject: [PATCH 05/10] added types

---
 packages/signer-cli/src/cmdSendOffline.ts | 52 +++++++++++++----------
 1 file changed, 30 insertions(+), 22 deletions(-)

diff --git a/packages/signer-cli/src/cmdSendOffline.ts b/packages/signer-cli/src/cmdSendOffline.ts
index 3b813e837..b259948bd 100644
--- a/packages/signer-cli/src/cmdSendOffline.ts
+++ b/packages/signer-cli/src/cmdSendOffline.ts
@@ -2,11 +2,14 @@
 // This software may be modified and distributed under the terms
 // of the Apache-2.0 license. See the LICENSE file for details.
 
-import * as readline from "readline";
-import { ApiPromise, WsProvider } from "@polkadot/api";
-import { assert } from "@polkadot/util";
+import * as readline from 'readline';
+import { ApiPromise, WsProvider } from '@polkadot/api';
+import { Index, SignerPayload, BlockNumber } from '@polkadot/types/interfaces';
+import { SubmittableExtrinsic, SignerOptions } from '@polkadot/api/submittable/types';
+import { Compact } from '@polkadot/types';
+import { assert } from '@polkadot/util';
 
-function getSignature(data: any) {
+function getSignature (data: string): Promise<string> {
   const rl = readline.createInterface({
     input: process.stdin,
     output: process.stdout
@@ -20,56 +23,61 @@ function getSignature(data: any) {
   });
 }
 
-export default async function cmdSendOffline(
+export default async function cmdSendOffline (
   account: string,
   blocks: number | undefined,
   endpoint: string,
+  nonce: number | undefined | Index,
   [tx, ...params]: string[]
 ): Promise<void> {
   const provider = new WsProvider(endpoint);
   const api = await ApiPromise.create({ provider });
-  const [section, method] = tx.split(".");
+  const [section, method] = tx.split('.');
 
   assert(api.tx[section] && api.tx[section][method], `Unable to find method ${section}.${method}`);
 
-  const options: any = {};
-  let blockNumber: any;
+  let options: SignerOptions | object = {};
+  let blockNumber: Compact<BlockNumber> | number | null = null;
+  nonce = nonce || await api.query.system.accountNonce(account);
 
   if (blocks === 0) {
-    options.era = 0;
-    options.blockHash = api.genesisHash;
+    options = {
+      era: 0,
+      blockHash: api.genesisHash,
+      nonce
+    };
     blockNumber = 0;
   } else if (blocks != null) {
     // Get current block if we want to modify the number of blocks we have to sign
     const signedBlock = await api.rpc.chain.getBlock();
-
-    options.blockHash = signedBlock.block.header.hash;
-    options.era = api.createType("ExtrinsicEra", {
-      current: signedBlock.block.header.number,
-      period: blocks
-    });
+    options = {
+      blockHash: signedBlock.block.header.hash,
+      era: api.createType('ExtrinsicEra', {
+        current: signedBlock.block.header.number,
+        period: blocks
+      }),
+      nonce
+    };
     blockNumber = signedBlock.block.header.number;
   }
 
-  const transaction: any = api.tx[section][method](...params);
-  const nonce: any = await api.query.system.accountNonce(account);
+  const transaction: SubmittableExtrinsic<'promise'> = api.tx[section][method](...params);
 
-  const payload: any = api.createType("SignerPayload", {
+  const payload: SignerPayload = api.createType('SignerPayload', {
     version: api.extrinsicVersion,
     runtimeVersion: api.runtimeVersion,
     genesisHash: api.genesisHash,
     ...options,
     address: account,
     method: transaction.method,
-    blockNumber,
-    nonce
+    blockNumber
   });
 
   const signature = await getSignature(payload.toRaw().data);
 
   transaction.addSignature(account, signature, payload.toPayload());
 
-  console.log("\nSigned transaction:\n" + transaction.toJSON());
+  console.log('\nSigned transaction:\n' + transaction.toJSON());
 
   process.exit(0);
 }

From ab9047e143cbbb6e27af2ed00b7f2ce185ad65a1 Mon Sep 17 00:00:00 2001
From: Marcin Zolkiewski <zolkiewski.marcin@gmail.com>
Date: Fri, 10 Jan 2020 00:47:56 +0100
Subject: [PATCH 06/10] fixed nonce logic

---
 packages/signer-cli/src/cmdSendOffline.ts | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/packages/signer-cli/src/cmdSendOffline.ts b/packages/signer-cli/src/cmdSendOffline.ts
index b259948bd..9c93cf0dd 100644
--- a/packages/signer-cli/src/cmdSendOffline.ts
+++ b/packages/signer-cli/src/cmdSendOffline.ts
@@ -36,9 +36,13 @@ export default async function cmdSendOffline (
 
   assert(api.tx[section] && api.tx[section][method], `Unable to find method ${section}.${method}`);
 
-  let options: SignerOptions | object = {};
+  if (nonce == null) {
+    nonce = await api.query.system.accountNonce(account);
+  }
+  let options: SignerOptions | object = {
+    nonce
+  };
   let blockNumber: Compact<BlockNumber> | number | null = null;
-  nonce = nonce || await api.query.system.accountNonce(account);
 
   if (blocks === 0) {
     options = {

From c5fda7719f4104ce1fbba649057e3375754ab1c5 Mon Sep 17 00:00:00 2001
From: Marcin Zolkiewski <zolkiewski.marcin@gmail.com>
Date: Fri, 10 Jan 2020 01:21:25 +0100
Subject: [PATCH 07/10] improved yargs docs

---
 packages/signer-cli/src/signer.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/signer-cli/src/signer.ts b/packages/signer-cli/src/signer.ts
index e1a39c7eb..7d7da6056 100644
--- a/packages/signer-cli/src/signer.ts
+++ b/packages/signer-cli/src/signer.ts
@@ -39,7 +39,7 @@ const { _: [command, ...params], account, blocks, nonce, minutes, seed, type, ws
       type: 'number'
     },
     blocks: {
-      description: 'Exact number of blocks for a transaction to be signed and submitted before becoming invalid (mortality in blocks). Set to 0 for an immortal transaction (not recomended, but useful for \'sendOffline\' command to ensure the transaction does not expire)',
+      description: 'Exact number of blocks for a transaction to be signed and submitted before becoming invalid (mortality in blocks). Set to 0 for an immortal transaction (not recomended)',
       default: undefined as number | undefined,
       type: 'number'
     },
@@ -49,7 +49,7 @@ const { _: [command, ...params], account, blocks, nonce, minutes, seed, type, ws
       type: 'number'
     },
     ws: {
-      description: 'The API endpoint to connect to, e.g. wss://poc3-rpc.polkadot.io (submit only)',
+      description: 'The API endpoint to connect to, e.g. wss://poc3-rpc.polkadot.io (submit and sendOffline only)',
       type: 'string'
     }
   })

From 428990f40b5ac80bbaca0edc119462964926cdc3 Mon Sep 17 00:00:00 2001
From: Marcin Zolkiewski <zolkiewski.marcin@gmail.com>
Date: Fri, 10 Jan 2020 01:22:07 +0100
Subject: [PATCH 08/10] improved logic and added default blocks

---
 packages/signer-cli/src/cmdSendOffline.ts | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/packages/signer-cli/src/cmdSendOffline.ts b/packages/signer-cli/src/cmdSendOffline.ts
index 9c93cf0dd..7a9875752 100644
--- a/packages/signer-cli/src/cmdSendOffline.ts
+++ b/packages/signer-cli/src/cmdSendOffline.ts
@@ -36,6 +36,9 @@ export default async function cmdSendOffline (
 
   assert(api.tx[section] && api.tx[section][method], `Unable to find method ${section}.${method}`);
 
+  if (blocks == null) {
+    blocks = 50;
+  }
   if (nonce == null) {
     nonce = await api.query.system.accountNonce(account);
   }
@@ -47,11 +50,10 @@ export default async function cmdSendOffline (
   if (blocks === 0) {
     options = {
       era: 0,
-      blockHash: api.genesisHash,
-      nonce
+      blockHash: api.genesisHash
     };
     blockNumber = 0;
-  } else if (blocks != null) {
+  } else {
     // Get current block if we want to modify the number of blocks we have to sign
     const signedBlock = await api.rpc.chain.getBlock();
     options = {
@@ -59,8 +61,7 @@ export default async function cmdSendOffline (
       era: api.createType('ExtrinsicEra', {
         current: signedBlock.block.header.number,
         period: blocks
-      }),
-      nonce
+      })
     };
     blockNumber = signedBlock.block.header.number;
   }

From 6be09476ceea32dc3c14b1f0a35b4469fc73df71 Mon Sep 17 00:00:00 2001
From: Marcin Zolkiewski <zolkiewski.marcin@gmail.com>
Date: Fri, 10 Jan 2020 01:24:42 +0100
Subject: [PATCH 09/10] added sendOffline to readme

---
 packages/signer-cli/README.md | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/packages/signer-cli/README.md b/packages/signer-cli/README.md
index 173a77706..230f89566 100644
--- a/packages/signer-cli/README.md
+++ b/packages/signer-cli/README.md
@@ -40,3 +40,17 @@ Signature: 0xe6facf194a8e...413ce3155c2d1240b
 Paste this signature into the submission in the first terminal, and off we go.
 
 By default, `submit` will create a mortal extrinsic with a lifetime of 50 blocks. Assuming a six-second block time, you will have five minutes to go offline, sign the transaction, paste the signature, and submit the signed transaction.
+
+## Send offline
+
+This functionality lets you generate signed transaction for execution at a later date. It is intended to resemble MyEtherWallet's [`Send offline`](https://kb.myetherwallet.com/en/offline/offline_transaction/) feature.
+
+The flow is similar to the `submit` command. First, run the `sendOffline` command on a computer with a network connection:
+
+`yarn run:signer sendOffline --account 5HNHXTw65dTNVGRdYkxFUpKcvmUYQMZHcDHmSKpuC8pvVEaN --ws wss://poc3-rpc.polkadot.io/ balances.transfer 5DkQbYAExs3M2sZgT1Ec3mKfZnAQCL4Dt9beTCknkCUn5jzo 123`
+
+This will give you a payload to sign. Use the `sign` command as per instructions above.
+
+Once you've pasted the signature into the `sendOffline` terminal (and hit `Enter`), it will print the signed transaction that can be stored and submitted later.
+
+Run `yarn run:signer --help` to learn about optional parameters.

From 38a63a877dd38a72f14bc7d4406cb7eef47f82d1 Mon Sep 17 00:00:00 2001
From: Marcin Zolkiewski <zolkiewski.marcin@gmail.com>
Date: Fri, 10 Jan 2020 02:01:25 +0100
Subject: [PATCH 10/10] support submitting pre-signed transactions

---
 packages/signer-cli/README.md        | 10 ++++++++--
 packages/signer-cli/src/cmdSubmit.ts | 21 +++++++++++++++++++--
 packages/signer-cli/src/signer.ts    | 15 +++++++++------
 3 files changed, 36 insertions(+), 10 deletions(-)

diff --git a/packages/signer-cli/README.md b/packages/signer-cli/README.md
index 230f89566..b905afeb4 100644
--- a/packages/signer-cli/README.md
+++ b/packages/signer-cli/README.md
@@ -21,6 +21,12 @@ Signature>
 
 The `Payload` is the hex that needs to be signed. Pasting the hex signature (followed by `Enter`) submits it to the chain.
 
+You can also use this command to submit pre-signed transactions, e.g. generated using the `sendOffline` command (see below).
+
+The syntax is as follows:
+
+`yarn run:signer submit --tx <signedTransaction> --ws <endpoint>`
+
 ## Sign a transaction
 
 To sign, you do not need a network connection at all and this command does not use the API to make connections to a chain. In a terminal, run the `sign` command with the following form:
@@ -43,7 +49,7 @@ By default, `submit` will create a mortal extrinsic with a lifetime of 50 blocks
 
 ## Send offline
 
-This functionality lets you generate signed transaction for execution at a later date. It is intended to resemble MyEtherWallet's [`Send offline`](https://kb.myetherwallet.com/en/offline/offline_transaction/) feature.
+This functionality lets you generate signed transactions for execution at a later time, on a different device or using other tools. It is intended to resemble MyEtherWallet's [`Send offline`](https://kb.myetherwallet.com/en/offline/offline_transaction/) feature.
 
 The flow is similar to the `submit` command. First, run the `sendOffline` command on a computer with a network connection:
 
@@ -51,6 +57,6 @@ The flow is similar to the `submit` command. First, run the `sendOffline` comman
 
 This will give you a payload to sign. Use the `sign` command as per instructions above.
 
-Once you've pasted the signature into the `sendOffline` terminal (and hit `Enter`), it will print the signed transaction that can be stored and submitted later.
+Once you've pasted the signature into the `sendOffline` terminal (and hit `Enter`), it will print the signed transaction that can be stored and submitted later (e.g. using the `submit` command).
 
 Run `yarn run:signer --help` to learn about optional parameters.
diff --git a/packages/signer-cli/src/cmdSubmit.ts b/packages/signer-cli/src/cmdSubmit.ts
index 21c7ac8d7..4eb6e8623 100644
--- a/packages/signer-cli/src/cmdSubmit.ts
+++ b/packages/signer-cli/src/cmdSubmit.ts
@@ -26,11 +26,28 @@ class RawSigner implements Signer {
   }
 }
 
-export default async function cmdSubmit (account: string, blocks: number | undefined, endpoint: string, [tx, ...params]: string[]): Promise<void> {
+function submitPreSignedTx (api: ApiPromise, tx: string): void {
+  const extrinsic = api.createType('Extrinsic', tx);
+
+  api.rpc.author.submitAndWatchExtrinsic(extrinsic, result => {
+    console.log(JSON.stringify(result));
+
+    if (result.isFinalized) {
+      process.exit(0);
+    }
+  });
+}
+
+export default async function cmdSubmit (account: string, blocks: number | undefined, endpoint: string, tx: string | undefined, [txName, ...params]: string[]): Promise<void> {
   const signer = new RawSigner();
   const provider = new WsProvider(endpoint);
   const api = await ApiPromise.create({ provider, signer });
-  const [section, method] = tx.split('.');
+
+  if (tx) {
+    return submitPreSignedTx(api, tx);
+  }
+
+  const [section, method] = txName.split('.');
 
   assert(api.tx[section] && api.tx[section][method], `Unable to find method ${section}.${method}`);
 
diff --git a/packages/signer-cli/src/signer.ts b/packages/signer-cli/src/signer.ts
index 7d7da6056..f6b5eb3fc 100644
--- a/packages/signer-cli/src/signer.ts
+++ b/packages/signer-cli/src/signer.ts
@@ -11,7 +11,7 @@ import cmdSendOffline from './cmdSendOffline';
 const BLOCKTIME = 6;
 const ONE_MINUTE = 60 / BLOCKTIME;
 
-const { _: [command, ...params], account, blocks, nonce, minutes, seed, type, ws } = yargs
+const { _: [command, ...params], account, blocks, minutes, nonce, seed, type, ws, tx } = yargs
   .usage('Usage: [options] <endpoint> <...params>')
   .usage('Example: submit --account D3AhD...wrx --ws wss://... balances.transfer F7Gh 10000 ')
   .usage('Example: sign --seed "..." --account D3AhD...wrx --type ed25519 0x123...789')
@@ -20,8 +20,7 @@ const { _: [command, ...params], account, blocks, nonce, minutes, seed, type, ws
   .options({
     account: {
       description: 'The actual address for the signer',
-      type: 'string',
-      required: true
+      type: 'string'
     },
     seed: {
       description: 'The account seed to use (sign only)',
@@ -51,6 +50,10 @@ const { _: [command, ...params], account, blocks, nonce, minutes, seed, type, ws
     ws: {
       description: 'The API endpoint to connect to, e.g. wss://poc3-rpc.polkadot.io (submit and sendOffline only)',
       type: 'string'
+    },
+    tx: {
+      description: 'Pre-signed transaction generated using e.g. the sendOffline command. If provided, only --ws is required as well (submit only)',
+      type: 'string'
     }
   })
   .strict()
@@ -60,13 +63,13 @@ const { _: [command, ...params], account, blocks, nonce, minutes, seed, type, ws
 // eslint-disable-next-line @typescript-eslint/require-await
 async function main (): Promise<void> {
   if (command === 'sign') {
-    return cmdSign(account, seed || '', type as 'ed25519', params);
+    return cmdSign(account as string, seed || '', type as 'ed25519', params);
   } else if (command === 'submit') {
     const mortality = minutes != null ? minutes * ONE_MINUTE : blocks;
-    return cmdSubmit(account, mortality, ws || '', params);
+    return cmdSubmit(account as string, mortality, ws || '', tx, params);
   } else if (command === 'sendOffline') {
     const mortality = minutes != null ? minutes * ONE_MINUTE : blocks;
-    return cmdSendOffline(account, mortality, ws || '', nonce, params);
+    return cmdSendOffline(account as string, mortality, ws || '', nonce, params);
   }
 
   throw new Error(`Unknown command '${command}' found, expected one of 'sign', 'submit' or 'sendOffline'`);