Expose eth_signTypedData functionality for order signing

packages/web3-wrapper/src/web3_wrapper.ts

@@ -314,6 +314,21 @@ export class Web3Wrapper {
         });
         return signData;
     }
+    /**
+     * Sign an EIP712 typed data message with a specific address's private key (`eth_signTypedData`)
+     * @param address Address of signer
+     * @param typedData Typed data message to sign
+     * @returns Signature string (might be VRS or RSV depending on the Signer)
+     */
+    public async signTypedDataAsync(address: string, typedData: object): Promise<string> {
+        assert.isETHAddressHex('address', address);
+        assert.doesConformToSchema('typedData', typedData, schemas.eip712TypedData);
+        const signData = await this.sendRawPayloadAsync<string>({
+            method: 'eth_signTypedData',
+            params: [address, typedData],
+        });
+        return signData;
+    }
     /**
      * Fetches the latest block number
      * @returns Block number