From 95f709b795c75ed6d15f5e2c68f05384a6b9c8e6 Mon Sep 17 00:00:00 2001
From: Karishma <bothara.karishma@gmail.com>
Date: Wed, 26 Jul 2023 08:43:45 +0530
Subject: [PATCH] Add example for Fee Preferences and proxy extrinsic which is
 a fpass proxy call (#20)

* Add example for Fee Preferences and proxy extrinsic which is a fpass proxy call


Co-authored-by: Ken Vu <97480229+ken-centrality@users.noreply.github.com>
---
 examples/substrate/use-feeProxy/README.md     | 19 +++++++
 .../src/feeProxyWithProxyExtrinsic.ts         | 52 +++++++++++++++++++
 2 files changed, 71 insertions(+)
 create mode 100644 examples/substrate/use-feeProxy/src/feeProxyWithProxyExtrinsic.ts

diff --git a/examples/substrate/use-feeProxy/README.md b/examples/substrate/use-feeProxy/README.md
index 425c818..da5b5ea 100644
--- a/examples/substrate/use-feeProxy/README.md
+++ b/examples/substrate/use-feeProxy/README.md
@@ -23,3 +23,22 @@ Run the command below to execute the example script, passing in a Payment Asset
 ```
 pnpm call src/callWithFeePreferences.ts --paymentAsset=<Payment Asset ID>
 ```
+
+### Call with Fee Preferences and proxy extrinsic
+
+Using the `feeProxy.callWithFeePreferences(paymentAsset, maxPayment, proxyExtrinsic)` extrinsic
+
+- `paymentAsset` - The token to be used for paying gas fees
+- `maxPayment` - The limit of how many tokens will be used to perform the exchange
+- `proxyExtrinsic` - The inner call to be performed after the exchange. Here proxy extrinsic is fpass proxy call
+- `const proxyExtrinsic = api.tx.futurepass.proxyExtrinsic(futurepassAddress, innerCall);`
+
+```
+api.tx.feeProxy.callWithFeePreferences(1, 3_000_000, api.tx.system.remark("Hello World"));
+```
+
+Run the command below to execute the example script, passing in a Payment Asset ID
+
+```
+pnpm call src/callWithFeePreferences.ts --paymentAsset=<Payment Asset ID>
+```
diff --git a/examples/substrate/use-feeProxy/src/feeProxyWithProxyExtrinsic.ts b/examples/substrate/use-feeProxy/src/feeProxyWithProxyExtrinsic.ts
new file mode 100644
index 0000000..032ef16
--- /dev/null
+++ b/examples/substrate/use-feeProxy/src/feeProxyWithProxyExtrinsic.ts
@@ -0,0 +1,52 @@
+import { collectArgs } from "@trne/utils/collectArgs";
+import { createKeyring } from "@trne/utils/createKeyring";
+import { filterExtrinsicEvents } from "@trne/utils/filterExtrinsicEvents";
+import { getChainApi } from "@trne/utils/getChainApi";
+import { sendExtrinsic } from "@trne/utils/sendExtrinsic";
+import assert from "assert";
+import { cleanEnv, str } from "envalid";
+
+const argv = collectArgs();
+
+const env = cleanEnv(process.env, {
+	CALLER_PRIVATE_KEY: str(), // private key of extrinsic caller
+});
+
+// This example assumes, there is liquidity pool for paymentAsset AND XrpAsset (100,000,000,000 & 100,000,000,000)
+// Also assumes, that the futurepassAddress has payment asset.
+export async function main() {
+	assert("paymentAsset" in argv, "Payment asset ID is required");
+
+	const api = await getChainApi("porcini");
+	const caller = createKeyring(env.CALLER_PRIVATE_KEY);
+	const fpassAddress = (await api.query.futurepass.holders(caller.address)).toString();
+	const { paymentAsset } = argv as unknown as { paymentAsset: number };
+
+	// can be any extrinsic, using `system.remarkWithEvent` for simplicity
+	const innerCall = api.tx.system.remarkWithEvent("Hello World");
+
+	const proxyExtrinsic = api.tx.futurepass.proxyExtrinsic(fpassAddress, innerCall);
+	const maxPayment = 1000000;
+	const feeProxiedCall = api.tx.feeProxy.callWithFeePreferences(
+		paymentAsset,
+		maxPayment,
+		proxyExtrinsic
+	);
+	const { result } = await sendExtrinsic(feeProxiedCall, caller, {
+		log: console,
+	});
+
+	const [proxyEvent, remarkEvent] = filterExtrinsicEvents(result.events, [
+		"FeeProxy.CallWithFeePreferences",
+		// depending on what extrinsic call you have, filter out the right event here
+		"System.Remarked",
+	]);
+	console.log("Extrinsic Result", {
+		proxy: proxyEvent.toJSON(),
+		remark: remarkEvent.toJSON(),
+	});
+
+	await api.disconnect();
+}
+
+main();