Answers for "(Reason: CORS header ‘Access-Control-Allow-Origin’ missing)"

access-control-allow-origin htaccess

<IfModule mod_headers.c>    
    Header set Access-Control-Allow-Origin *
</IfModule>

Reason: CORS header 'Access-Control-Allow-Origin' missing

const app = express();

// CORS configuration
const corsOptions = {
    origin: 'http://localhost:3000',
    credentials: true
}

// The following is not needed, CORS middleware will be applied
// using the Apollo Server's middleware API (see further below)
// app.use(cors(corsOptions))

// Setup JWT authentication middleware
app.use(async (req, res, next) => {
    const token = req.headers['authorization'];
    if(token !== "null"){
        try {
            const currentUser = await jwt.verify(token, process.env.SECRET)
            req.currentUser = currentUser
        } catch(e) {
            console.error(e);
        }
    }
    next();
});

const server = new ApolloServer({ 
    typeDefs, 
    resolvers, 
    context: ({ req }) => ({ Property, User, currentUser: req.currentUser })
});

// There is no need to explicitly define the 'path' option in
// the configuration object as '/graphql' is the default endpoint
// If you planned on using a different endpoint location,
// this is where you would define it.
server.applyMiddleware({ app, cors: corsOptions });

const PORT = process.env.PORT || 4000;

app.listen(PORT, () => {
    console.log(`Server listening on ${PORT}`);
})