I am attempting to write a function that checks if the userId/channelId is valid by looping through the data store below.
let data = {
users: [
{
uId: 1,
email: 'kif@kmail.com',
password: 'kif123',
nameFirst: 'Kifaya',
nameLast: 'Shehadeh',
handle: 'kifayashehadeh',
},
{
uId: 2,
email: 'yus@ymail.com',
password: 'yus1234',
nameFirst: 'Yusra',
nameLast: 'Mahomed',
handle: 'yusramahomed',
},
],
channels: [
{
channelId: 1,
name: 'DREAM',
ownerMembers: [1,2,3,4,5],
allMembers: [1,2,3,4,5],
isPublic: false,
messages: [
{
messageId: 1,
uId: 1,
message: "Coffee is better at 12am.",
timeSent: Math.floor((new Date()).getTime() / 1000),
},
{
messageId: 2,
uId: 2,
message: "Chocolate is better 24/7.",
timeSent: Math.floor((new Date()).getTime() / 1000),
},
],
},
{
channelId: 2,
name: 'COFFEE',
ownerMembers: [1,2],
allMembers: [1,2,3,4,5],
isPublic: true,
messages: [
{
messageId: 1,
uId: 4,
message: "Dark chocolate isn't even chocolate. Seriously.",
timeSent: Math.floor((new Date()).getTime() / 1000),
},
],
},
],
};
This is currently the way I am doing it inside of a function:
//invalid channelId
let error = true;
for (const channel of data.channels) {
if (channel.channelId !== channelId ) {
error = false;
}
}
//invalid user
for (const user of data.users) {
if (user.uId === authUserId) {
error = false;
}
}
if (error === true) {
return {
error : 'error'
}
}
This method seems very inefficient and more like C than javascript, I was wondering if there were any magical single lines of code that could do some of that for me without being so unreadable. I am also finding a hard time figuring out how to make the error checking work correctly. Is there a way that allows me to return the error immediately so that it exits from the function the first time it detects an error?
I'd map both the users and the channels to just the properties you're interested in - .channelId and .uid - and then just use .includes twice to see that both values are included in both arrays.
const channelIds = data.channels.map(c => c.channelId);
const userIds = data.users.map(u => u.uId);
if (
!channelIds.includes(channelId) ||
!userIds.includes(authUserId)
) {
return {
error: 'error'
};
}
It's possible to put into a single line, but it's less readable. (Technically, any JavaScript code could be put into a single line - but that doesn't make it a good idea from a maintainability standpoint.)
if (!data.channels.map(c => c.channelId).includes(channelId) || !data.users.map(u => u.uId).includes(authUserId)) { return { error: 'error' };}