feat: add deeplink compression logic to sdk-multichain

packages/sdk-multichain/package.json

@@ -33,6 +33,7 @@
     "@metamask/auto-changelog": "^3.4.3",
     "@react-native-async-storage/async-storage": "^1.23.1",
     "@types/jsdom": "^21.1.7",
+    "@types/pako": "^2.0.4",
     "@types/ws": "^8.18.1",
     "@vitest/coverage-v8": "^3.2.4",
     "esbuild-plugin-umd-wrapper": "^3.0.0",
@@ -66,6 +67,7 @@
     "cross-fetch": "^4.1.0",
     "eciesjs": "^0.4.15",
     "eventemitter3": "^5.0.1",
+    "pako": "^2.1.0",
     "uuid": "^11.1.0",
     "ws": "^8.18.3"
   }

packages/sdk-multichain/src/multichain/utils/index.ts

@@ -1,9 +1,38 @@
+import { deflate } from 'pako';
 import { type CaipAccountId, type CaipChainId, parseCaipAccountId, parseCaipChainId } from '@metamask/utils';
 import packageJson from '../../../package.json';
 import { type DappSettings, getInfuraRpcUrls, getPlatformType, type MultichainOptions, PlatformType, type Scope, type SessionData } from '../../domain';
 
 export type OptionalScopes = Record<Scope, SessionData['sessionScopes'][Scope]>;
 
+/**
+ * Cross-platform base64 encoding
+ * Works in browser, Node.js, and React Native environments
+ */
+function base64Encode(str: string): string {
+	if (typeof btoa !== 'undefined') {
+		// Browser and React Native with polyfills
+		return btoa(str);
+	} else if (typeof Buffer !== 'undefined') {
+		// Node.js
+		return Buffer.from(str).toString('base64');
+  }
+	throw new Error('No base64 encoding method available');
+}
+
+/**
+ * Compress a string using pako (deflateRaw)
+ * Returns a base64-encoded compressed string
+ */
+export function compressString(str: string): string {
+	const compressed = deflate(str);
+
+	// Convert Uint8Array to string for base64 encoding
+	const binaryString = String.fromCharCode.apply(null, Array.from(compressed));
+	return base64Encode(binaryString);
+}
+
+
 export function getDappId(dapp?: DappSettings) {
 	if (typeof window === 'undefined' || typeof window.location === 'undefined') {
 		return dapp?.name ?? dapp?.url ?? 'N/A';

packages/sdk-multichain/src/ui/index.ts

@@ -2,6 +2,7 @@ import MetaMaskOnboarding from '@metamask/onboarding';
 import { type ConnectionRequest, getPlatformType, getVersion, type Modal, type OTPCode, PlatformType } from '../domain';
 import type { FactoryModals, ModalTypes } from './modals/types';
 import type { AbstractOTPCodeModal } from './modals/base/AbstractOTPModal';
+import { compressString } from '../multichain/utils';
 import { METAMASK_CONNECT_BASE_URL, METAMASK_DEEPLINK_BASE } from 'src/config';
 
 // @ts-ignore
@@ -90,15 +91,17 @@ export class ModalFactory<T extends FactoryModals = FactoryModals> {
 	}
 
 	createDeeplink(connectionRequest: ConnectionRequest) {
-		const json = JSON.stringify(connectionRequest);
-		const urlEncoded = encodeURIComponent(json);
-		return `${METAMASK_DEEPLINK_BASE}/mwp?p=${urlEncoded}`;
+    const json = JSON.stringify(connectionRequest);
+    const compressed = compressString(json);
+    const urlEncoded = encodeURIComponent(compressed);
+    return `${METAMASK_DEEPLINK_BASE}/mwp?p=${urlEncoded}&c=1`;
 	}
 
 	createUniversalLink(connectionRequest: ConnectionRequest) {
 		const json = JSON.stringify(connectionRequest);
-		const urlEncoded = encodeURIComponent(json);
-		return `${METAMASK_CONNECT_BASE_URL}/mwp?p=${urlEncoded}`;
+    const compressed = compressString(json);
+		const urlEncoded = encodeURIComponent(compressed);
+		return `${METAMASK_CONNECT_BASE_URL}/mwp?p=${urlEncoded}&c=1`;
 	}
 
 	private async onCloseModal(shouldTerminate = true) {

yarn.lock

@@ -11583,6 +11583,7 @@ __metadata:
     "@paulmillr/qr": ^0.2.1
     "@react-native-async-storage/async-storage": ^1.23.1
     "@types/jsdom": ^21.1.7
+    "@types/pako": ^2.0.4
     "@types/ws": ^8.18.1
     "@vitest/coverage-v8": ^3.2.4
     bowser: ^2.11.0
@@ -11593,6 +11594,7 @@ __metadata:
     fake-indexeddb: ^6.0.1
     jsdom: ^26.1.0
     nock: ^14.0.4
+    pako: ^2.1.0
     prettier: ^3.3.3
     tsup: ^8.5.0
     typescript: ^5.8.3
@@ -20236,6 +20238,13 @@ __metadata:
   languageName: node
   linkType: hard
 
+"@types/pako@npm:^2.0.4":
+  version: 2.0.4
+  resolution: "@types/pako@npm:2.0.4"
+  checksum: 7e7b090c27cdbed4a8c21f7dfa466ad1c6b5c29afbcaaa24b35e83803d2b6b6cd552060060d8832058cf3809787baaab47a6a974b69d75a2a2dc59d21b607ee8
+  languageName: node
+  linkType: hard
+
 "@types/parse-json@npm:^4.0.0":
   version: 4.0.0
   resolution: "@types/parse-json@npm:4.0.0"
@@ -44907,6 +44916,13 @@ __metadata:
   languageName: node
   linkType: hard
 
+"pako@npm:^2.1.0":
+  version: 2.1.0
+  resolution: "pako@npm:2.1.0"
+  checksum: 71666548644c9a4d056bcaba849ca6fd7242c6cf1af0646d3346f3079a1c7f4a66ffec6f7369ee0dc88f61926c10d6ab05da3e1fca44b83551839e89edd75a3e
+  languageName: node
+  linkType: hard
+
 "pako@npm:~0.2.0":
   version: 0.2.9
   resolution: "pako@npm:0.2.9"