🌒🎓 ↝ Adding graphql endpoint to allow for authentication & signing wi…

…th Lens Protocol

We'll eventually redesign the layout of the post form (publication) to be in-line with the proposal layout in Signal-K/Silfur#25
User inputs & signature actions will be sent to the server as desired in Signal-K/Silfur#24
And of course, the user will now be authoring publications from the frontend, Signal-K/Silfur#22

Server/Pipfile

@@ -13,4 +13,4 @@ python-dotenv = "*"
 [dev-packages]
 
 [requires]
-python_version = "3.10"
+python_version = "3.9.9"

Server/app.py

@@ -69,4 +69,8 @@ def logout():
         'none',
         expires=datetime.utcnow() + timedelta(second = 5)
     )
-    return res, 200
+    return res, 200
+
+@app.route('/helloworld')
+def helloworld():
+    return address

Server/frontend/components/Navbar.js

@@ -0,0 +1,16 @@
+import { ConnectButton } from "web3uikit";
+
+
+export default function Navbar() {
+    return (
+        <ul>
+            <li>Home</li>
+            <li>Create Proposal</li>
+            <li>
+                <div>
+                    <ConnectButton moralisAuth={false} />
+                </div>
+            </li>
+        </ul>
+    )
+};

Server/frontend/constants/lensConstants.js

@@ -0,0 +1,46 @@
+import { ApolloClient, InMemoryCache, gql } from "@apollo/client";
+
+const API_URL = 'https://api.lens.dev';
+
+export const lensClient = new ApolloClient({
+    uri: API_URL,
+    cache: new InMemoryCache(),
+});
+
+export const challenge = gql`
+  query Challenge($address: EthereumAddress!) {
+    challenge(request: { address: $address }) {
+      text
+    }
+  }
+`;
+
+// Provide access & refresh token to determine Lens profile ID of the authenticated address
+export const lensAuthenticate = gql`
+  mutation Authenticate($address: EthereumAddress!, $signature: Signature!) {
+    authenticate(request: { address: $address, signature: $signature }) {
+      accessToken
+      refreshToken
+    }
+  }
+`;
+
+export const getDefaultProfile = gql`
+  query DefaultProfile($request: DefaultProfileRequest!) {
+    defaultProfile(request: $request) {
+        id
+    }
+  }
+`
+
+export const getFollowing = gql`
+  query Query($request: FollowingRequest!) {
+    following(request: $request) {
+        items: {
+            profile {
+                id
+            }
+        }
+    }
+  }
+`

Server/frontend/context/lensContext.js

@@ -0,0 +1,94 @@
+import { useState, useEffect, createContext, useContext } from "react";
+import { challenge, lensClient, lensAuthenticate, getDefaultProfile } from '../constants/lensConstants';
+import { useMoralis } from "react-moralis";
+import { ethers } from "ethers";
+
+export const lensContext = createContext();
+export const useLensContext = () => {
+    return useContext(lensContext);
+}
+
+export function LensProvider({ children }) {
+    const [profileId, setProfileId] = useState();
+    const [token, setToken] = useState();
+    const { account } = useMoralis();
+
+    const signIn = async function () {
+        try {
+            const challengeInfo = await lensClient.query({
+                query: challenge,
+                variables: { address: account },
+            });
+
+            const provider = new ethers.providers.Web3Provider(window.ethereum);
+            const signer = provider.getSigner();
+            const signature = await signer.signMessage(challengeInfo.data.challenge.text);
+
+            const authData = await lensClient.mutate({
+                mutation: lensAuthenticate,
+                variables: {
+                    address: account,
+                    signature,
+                },
+            });
+
+            const {
+                data: {
+                    authenticate: { accessToken },
+                },
+            } = authData;
+            setToken(accessToken);
+            console.log(accessToken);
+        } catch (error) {
+            console.error("Error signing in, ", error);
+        }
+    };
+
+    const getProfileId = async function () {
+        const defaultProfile = await lensClient.query({
+            query: getDefaultProfile,
+            variables: {
+                request: {
+                    ethereumAddress: account,
+                },
+            },
+        });
+
+        if (defaultProfile.data.defaultProfile) {// Check to see if the connected wallet has a lens acct
+            console.log(defaultProfile.data.defaultProfile.id)
+            return defaultProfile.data.defaultProfile.id;
+        }
+        return null;
+    }
+
+    useEffect(() => {
+        const readToken = window.localStorage.getItem("lensToken");
+        if (readToken) {
+            setToken(readToken);
+        }
+
+        if (account && !token && !readToken) {
+            signIn();
+        }
+
+        if (!account) {
+            window.localStorage.removeItem("lensToken");
+        }
+
+        if (account) {
+            getProfileId().then((id) => setProfileId(id));
+        }
+    }, [account]);
+
+    useEffect(() => {
+        if (token) {
+            window.localStorage.setItem("lensToken", token);
+        }
+    }, [token]); // Whenever the token changes
+
+    return (
+        <lensContext.Provider value={{ profileId, token }}>
+          {children}
+        </lensContext.Provider>
+    );
+}