add message signing

dapp/src/utils/signing.ts

@@ -0,0 +1,32 @@
+declare var web3: any
+
+type signedMessage = {
+    address: string,
+    msg: string,
+    sig: string,
+    version: number
+}
+
+export function sign(message: string): Promise<string> {
+    return web3.eth.personal.sign(message, web3.eth.defaultAccount)
+}
+
+export function verify(message: string, sig: string): Promise<string> {
+    return web3.eth.personal.ecRecover(message, sig)
+}
+
+export async function verifySignedMessage(message: signedMessage): Promise<boolean> {
+    const { address, msg, sig } = message
+    const resAddress = await verify(msg, sig)
+    return address.toLowerCase() == resAddress.toLowerCase()
+}
+
+export async function prettySign(message: string): Promise<signedMessage> {
+    const sig = await sign(message)
+    return {
+        address: web3.eth.defaultAccount,
+        msg: message,
+        sig,
+        version: 2
+    };
+}