Test OpenGov Referenda before Submission (#6371)

* Test OpenGov Referenda before Submission

Used Chopsticks to test Polkadot OpenGov referenda with native and cross-chain calls

* Add info on connecting to local node

docs/learn/learn-guides-test-opengov-proposals.md

@@ -0,0 +1,205 @@
+---
+id: learn-guides-test-opengov-proposals
+title: Test OpenGov Referenda before Submission
+sidebar_label: Test OpenGov Referenda
+description: Polkadot-JS Guides about testing Polkadot OpenGov referenda using Chopsticks
+keywords: [opengov, polkadot opengov, referenda, polkadot-js]
+slug: ../learn-guides-test-opengov-proposals
+---
+
+A Polkadot OpenGov referendum always contains a call that will be executed after the referendum is
+voted in successfully. The referendum proposer is responsible for checking if the call gets executed
+successfully on-chain and whether an appropriate origin and track have been chosen. In the case of
+referenda that send a cross-chain call to the system chains, it is important to check whether the
+XCM call gets dispatched successfully from Polkadot and is received/executed as expected on the
+system chain.
+
+This tutorial aims to show how to test the calls to be submitted with the referendum and ensure they
+work as expected. Let us consider the two examples below:
+
+- Submitting a Treasury referendum that requests 4500 DOT
+- Submitting a referendum to remove ambassadors
+  ([Referendum 1247](https://polkadot.subsquare.io/referenda/1247))
+
+## Test a Polkadot OpenGov Referendum
+
+To request 4500 DOT from the treasury, you must create a pre-image with the call
+`treasury.spendLocal(amount,beneficiary)`. The guide for creating pre-images for treasury proposals
+and submitting them is available [here](learn-guides-polkadot-opengov.md) on the Wiki. The proposer
+needs to know the exact origin and track to submit this proposal. As this is a treasury proposal, it
+would be one of the treasury tracks -
+[SmallSpender](learn-polkadot-opengov-origins.md#small-spender) in the case of 4500 DOT.
+
+`0x13030b00d00361ed28009e4e7009937c56d267338762a60ed004293afd40e7c2081847c12cb63c76a818`
+
+![opengov-treasury-proposal-call](../assets/governance/opengov-call-test-treasury-proposal.png)
+
+### Fork a Network Locally using Chopsticks
+
+If you like to check whether the call above will get executed successfully, you can check that by
+performing a dry run using [Chopsticks](https://github.com/AcalaNetwork/chopsticks), which is
+embedded in Polkadot JS UI. You can run a Chopsticks instance of any Polkadot SDK based chain by
+clicking "fork locally" on the UI. The snapshot below shows it for Polkadot.
+
+![polkadot-fork-locally](../assets/governance/polkadot-fork-locally.png)
+
+After forking locally, the Polkadot JS UI displays a local instance of the Polkadot network, which
+does not produce any blocks by default. You will notice a few test accounts with DOT balance that
+can interact with the network and test out Polkadot protocol features accessible through regular
+accounts. However, the treasury spend call cannot be submitted through a signed account origin, so
+it has to be tested with a treasury track origin. It can be tested by navigating to Developer >
+Javascript tab on Polkadot JS UI, which dispatches the call on the next block via the scheduler with
+the specified origin.
+
+```
+const number = (await api.rpc.chain.getHeader()).number.toNumber()
+await api.rpc('dev_setStorage', {
+ scheduler: {
+   agenda: [
+     [
+       [number + 1], [
+         {
+           call: {
+             Inline: '0x13030b00d00361ed28009e4e7009937c56d267338762a60ed004293afd40e7c2081847c12cb63c76a818'
+           },
+           origin: {
+             origins: 'SmallSpender'
+           }
+         }
+       ]
+     ]
+   ]
+ }
+})
+await api.rpc('dev_newBlock')
+```
+
+![polkadot-chopstciks-call](../assets/governance/polkadot-chopsticks-call.png)
+
+After clicking the play button in the Javascript console, the block number visible on the top left
+of the Polkadot JS UI should be incremented by 1. You can navigate to Polkadot JS UI Network >
+Explorer to check the emitted events and see if the call was executed successfully. You should see
+the errors displayed here if the call is unsuccessful.
+
+![polkadot-js-ui-explorer](../assets/governance/polkadot-js-ui-explorer.png)
+
+## Test a Polkadot OpenGov Referendum with Cross-chain Calls
+
+Take the example of removing a member of the ambassador collective on the Collectives system chain
+through a Polkadot OpenGov referendum. Obtain the call data to remove a member from the ambassador
+collective in the Collectives system chain runtime.
+
+![collectives-remove-ambassador](../assets/governance/collectives-remove-member.png)
+
+Note down the call data and navigate to Developer > Runtime calls and fetch the weights for
+execution of the call through `transactionPaymentCallApi.queryCallInfo`. Here is the call info used
+in our example for your reference:
+`0x4603000c691601793de060491dab143dfae19f5f6413d4ce4c363637e5ceacb2836a4e0300`
+
+![tx-payment-call-api](../assets/governance/collectives-remove-call-weights.png)
+
+Now you have all the information you need to create an XCM call that needs to be sent from Polkadot.
+No fee payment is required for an XCM call dispatched through OpenGov. The Collectives chain
+`ParaID` is 1001. With this information, we can construct the XCM call shown below.
+
+`0x630004000100a50f04082f0000060303e3c4cc9589ad944603000c691601793de060491dab143dfae19f5f6413d4ce4c363637e5ceacb2836a4e0300`
+
+![unpaid-execution-xcm-call](../assets/governance/collectives-remove-xcm-call.png)
+
+### Cross-chain Testing setup using Chopsticks
+
+Testing this cross-chain call by [forking locally](#fork-a-network-locally-using-chopsticks) will
+only perform the required checks on the sending chain, not the receiving chain. To do cross-chain
+testing, download and install [Chopsticks](https://github.com/AcalaNetwork/chopsticks) on your
+machine and run the command below:
+
+`npx @acala-network/chopsticks@latest xcm -r polkadot -p polkadot-collectives`
+
+This should start the Polkadot and the Collectives instances available at ports 8001 and 8000
+respectively. Connect to both these instances using Polkadot JS UI on two separate browser windows.
+To connect to these local machine instances at the designated ports, edit the custom endpoint for
+Polkadot JS UI as shown in the picture below and click on Switch button at the top.
+
+![polkadot-js-local](../assets/governance/polkadot-js-local-node.png)
+
+Navigate to the Polkadot instance and open Javascript console to run the code below.
+
+```
+const number = (await api.rpc.chain.getHeader()).number.toNumber()
+await api.rpc('dev_setStorage', {
+ scheduler: {
+   agenda: [
+     [
+       [number + 1], [
+         {
+           call: {
+             Inline: '0x630004000100a50f04082f0000060303e3c4cc9589ad944603000c691601793de060491dab143dfae19f5f6413d4ce4c363637e5ceacb2836a4e0300'
+           },
+           origin: {
+             origins: 'FellowshipAdmin'
+           }
+         }
+       ]
+     ]
+   ]
+ }
+})
+await api.rpc('dev_newBlock')
+```
+
+![javascript-fellowship-admin](../assets/governance/javascript-console-fellowship-admin-call.png)
+
+After clicking on the play button in the Javascript console, the block number visible on the top
+left of the Polkadot JS UI should be incremented by 1. You can navigate to Polkadot JS UI Network >
+Explorer to check the emitted events and see if the call got executed successfully. If the call is
+unsuccessful, you should see the respective errors displayed here.
+
+**Successful XCM call dispatch shown on the Polkadot network:**
+
+![xcm-polkadot-send](../assets/governance/polkadot-send-xcm.png)
+
+You can then navigate to the local Collectives instance and check the events to confirm the call is
+executed as expected.
+
+**Successful XCM call receipt shown on the Collectives system chain:**
+
+![xcm-collectives-receive](../assets/governance/collectives-receive-xcm.png)
+
+Now, take the example of [Referendum 1247](https://polkadot.subsquare.io/referenda/1247) which
+executes a call that tries to remove 19 ambassadors from the collective at once. This is a very long
+call and exceeds the Javascript console `inLine` character limit. In that case, the code can be
+modified instead to lookup the preimage of call with the specified length and check if it is
+successfully executes.
+
+`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`
+
+The preimage hash of this call is
+`0x82802c62d52a2431e422b58fff1fbdd0efc648e7c98351bd26048d169b94f956` and its length is `733`
+(obtained from Polkadot JS UI Governance > Preimgaes tab for that lists the preimages that are
+already submitted).
+
+```
+const number = (await api.rpc.chain.getHeader()).number.toNumber()
+await api.rpc('dev_setStorage', {
+ scheduler: {
+   agenda: [
+     [
+       [number + 1], [
+         {
+           call: {
+             Lookup: {
+               hash: "0x82802c62d52a2431e422b58fff1fbdd0efc648e7c98351bd26048d169b94f956",
+               len: 733
+             }
+           },
+           origin: {
+             origins: 'FellowshipAdmin'
+           }
+         }
+       ]
+     ]
+   ]
+ }
+})
+await api.rpc('dev_newBlock')
+```

polkadot-wiki/sidebars.js

@@ -567,6 +567,7 @@ module.exports = {
                       ],
                     },
                     "learn/learn-guides-polkadot-opengov",
+                    "learn/learn-guides-test-opengov-proposals",
                     "learn/learn-guides-treasury",
                     "learn/learn-guides-bounties",
                     "learn/learn-guides-identity",