How to apply "select something in " in mongodb using nextjs? - javascript

I am exploring next.js with mongodb, however I faced a problem that I can't find an appropriate soulution on the Internet.
I have an api handle different request.
For the GET method, I want to pass different parameters(i.e. category and subcategory in this case) to apply different filters to grap data from mongodb.
Since there can be multiple subcategories, now the question is how can I properly perform the in-clause query here? I would like to perform something like
select * from post where category="music share" AND subcategoy in ("rock","metal")
It works fine when there is one subcategory only, but it will not work when there are more.
For the non working test case, current console.log returns-> query is: { category: 'music share', subcategory: 'rock,metal' }
async function getPosts(req,res){
var query={};
if (req.query.category){
query.category=req.query.category;
}
if (req.query.subcategory){
query.subcategory=req.query.subcategory;
}
try {
console.log("query is: ",query);
// connect to the database
let { db } = await connectToDatabase();
// fetch the posts
let posts = await db
.collection('posts')
.find(query)
.sort({ _id: -1 })
.toArray();
// return the posts
return res.json(JSON.parse(JSON.stringify(posts)));
} catch (error) {
// return the error
return res.json({
message: new Error(error).message,
success: false,
});
}
}

Related

How to insert data into mysql using angular and nodejs - getting (NULL, NULL) upon insert - Problem solved

Good day,
I've been trying to learn a bit of angular and nodejs. I found a tutorial on a realtime chat app and made some few adjustment to some function of the code. But the one aspect that I cannot seem to get right is the ability for the user to post to a feed. The login process works, the user is already logged in but the user can't post. I would also like to be able to get all they data i insert from all the user to show up like a normal feedview will. Please assist.
Here are my files:
FROM MY CONTROLLER HERE IS THE CODE WHEN THE BUTTON IS PRESSED
$scope.postDatatoDd = () => {
appService.httpCall({
url: '/posts',
params: {
'posts': $scope.data.info,
'from_user_id': $scope.data.username
}
})
.then((response) => {
// $scope.$apply();
})
.catch((error) => {
alert(error.message);
});
}
and here is my route file:
this.app.post('/posts', async(request,response) => {
const reqResponse = {}
const data = {
posts : request.body.postDatatoDd,
from_user_id: request.body.username
};
if (data.posts === ''){
reqResponse.error = true;
reqResponse.message = `error, input`;
response.status(412).json(reqResponse);
} else {
const result = await helper.insertFeed(data);
if (result === null) {
reqResponse.error = true;
reqResponse.message = `they was an error.`;
response.status(417).json(reqResponse);
} else {
reqResponse.error = false;
reqResponse.userId = result.insertId;
reqResponse.message = `posted succesfully`;
response.status(200).json(reqResponse);
}
}});
and in my helper file there is this function to insert data:
async insertFeed(params){
try {
return await this.db.query(
`INSERT INTO posts (from_user_id,posts) values (?,?)`,
[params.from_user_id,params.postDatatoDd]
);
} catch (error) {
console.warn(error);
return null;
}
}
On the client side here is the button with :
<label for="postDatatoDd">Post</label>
<input type="text" id="postDatatoDd"
ng-model="data.postDatatoDd"
class="feed form-control"
placeholder="post your data here?"
/>
<button ng-click="postDatatoDd()" class="btn btn-primary">Post</button>
</div>
--- EDIT 1---
Data is being inserted now, but it is receiving the values as (NULL, NULL).
--- EDIT 2 ---
After closely looking at the code and fixing some naming variables the code works fine, the data is being inserted in mysql as it should.
Other than a lot of typos when it comes to the variables reference. The code seem to be fine.
Assuming that you using appservice class somewhere in your code and its functioned, then everything else will work.
You are getting the (NULL, NULL) because you are parsing parameters that are not being properly parsed out to your helper file, please close attention to that.
appService
.httpCall({
url: "/posts",
params: {
posts: $scope.data.postbuzz,
from_user_id: $scope.data.username,
},
})
.then((response) => {
$scope.$apply();
})
.catch((error) => {
alert(error.message);
});
make sure that the data that you calling from this above function is similar to $scope parameter you passing in your route file that your requesting:
const data = {
posts : request.body.posts,
from_user_id: request.body.from_user_id}
and in your database helper class you running:
`INSERT INTO posts (from_user_id,post) values (?,?)`,
[params.from_user_id,params.posts]
Hope this was helpful
You seem to have an understand already. your question may help a lot more people in the future.
params should be as following, since the data object has properties from_user_id and posts
`INSERT INTO posts (from_user_id,posts) values (?, ?)`,
[params.from_user_id,params.posts]
Might be useful https://www.w3schools.com/nodejs/nodejs_mysql_insert.asp
--- EDIT 2 ---
After closely looking at the code and fixing some naming variables the code works fine, the data is being inserted in mysql as it should.
If you are new to Angular you can use the code as reference.

Vercel API end point for search sends back only results equal to the query term but not results that includes that term

I have written a component with react hooks, following a tutorial, that fetches result based on one field of an object that has the following structure. { id: 1, text: "Run 10 km", complete: false }
The user is supposed to search by the text of a todo task. I am using axios and I send the request to vercel.com like this:
const getToDosBasedOnQueryTerm = async (query) => {
try {
const response = await axios(`https://todos-api-nuquyjkqpx.now.sh/todos?text=${query}`);
console.log('**************************')
console.log(query);
console.log(response.data);
console.log('**************************')
return response.data;
} catch (error) {
console.log(error);
}
};
Here are all the todos: https://todos-api-nuquyjkqpx.now.sh/todos
There is a problem with this approach. It returns the results that has the exact text as in the query. So, if I search for Do, it returns 'Do' but ignores 'Do More' and 'Do Nothing'.
Is it possible to search for all the records (todos) that contain the word searched by the user?
Please help!
Thanks

Returning a record with a string in ember

I am trying to implement a search function where a user can return other users by passing a username through a component. I followed the ember guides and have the following code to do so in my routes file:
import Ember from 'ember';
export default Ember.Route.extend({
flashMessages: Ember.inject.service(),
actions: {
searchAccount (params) {
// let accounts = this.get('store').peekAll('account');
// let account = accounts.filterBy('user_name', params.userName);
// console.log(account);
this.get('store').peekAll('account')
.then((accounts) => {
return accounts.filterBy('user_name', params.userName);
})
.then((account) => {
console.log(account);
this.get('flashMessages')
.success('account retrieved');
})
.catch(() => {
this.get('flashMessages')
.danger('There was a problem. Please try again.');
});
}
}
});
This code, however, throws me the following error:
"You cannot pass '[object Object]' as id to the store's find method"
I think that this implementation of the .find method is no longer valid, and I need to go about returning the object in a different manner. How would I go about doing this?
You can't do .then for filterBy.
You can't do .then for peekAll. because both will not return the Promise.
Calling asynchronous code and inside the searchAccount and returning the result doesn't make much sense here. since searchAccount will return quickly before completion of async code.
this.get('store').findAll('account',{reload:true}).then((accounts) =>{
if(accounts.findBy('user_name', params.userName)){
// show exists message
} else {
//show does not exist message
}
});
the above code will contact the server, and get all the result and then do findBy for the filtering. so filtering is done in client side. instead of this you can do query,
this.store.query('account', { filter: { user_name: params.userName } }).then(accounts =>{
//you can check with length accounts.length>0
//or you accounts.get('firstObject').get('user_name') === params.userName
//show success message appropriately.
});
DS.Store#find is not a valid method in modern versions of Ember Data. If the users are already in the store, you can peek and filter them:
this.store.peekAll('account').filterBy('user_name', params.userName);
Otherwise, you'll need to use the same approach you used in your earlier question, and query them (assuming your backend supports filtering):
this.store.query('account', { filter: { user_name: params.userName } });

Firebase Real Time Database Structure for File Upload

I am working on my first Firebase project using AngularFire2. Below is the overall design of my learning project.
Users uploads photos and it's stored in the Firebase storage as images.
The uploaded photos are listed in the homepage sorted based on timestamp.
Below is the structure that I have now when I started. But I feel difficulty when doing joins. I should be able to get user details for each uploads and able to sort uploads by timestamp.
User:
- Name
- Email
- Avatar
Uploads:
- ImageURL
- User ID
- Time
I read few blogs de-normalising the data structure. For my given scenario, how best can i re-model my database structure?
Any example for creating some sample data in the new proposed solution will be great for my understanding.
Once the image upload is done, I am calling the below code to create an entry in the database.
addUpload(image: any): firebase.Promise<any> {
return firebase.database().ref('/userUploads').push({
user: firebase.auth().currentUser.uid,
image: image,
time: new Date().getTime()
});
}
I am trying to join 2 entities as below. i am not sure how can I do it efficiently and correctly.
getUploads(): any {
const rootDef = this.db.database.ref();
const uploads = rootDef.child('userUploads').orderByChild('time');
uploads.on('child_added',snap => {
let userRef =rootDef.child('userProfile/' + snap.child('user').val());
userRef.once('value').then(userSnap => {
???? HOW TO HANDLE HERE
});
});
return ?????;
}
I would like to get a final list having all upload details and its corresponding user data for each upload.
This type of join will always be tricky if you write it from scratch. But I'll try to walk you through it. I'm using this JSON for my answer:
{
uploads: {
Upload1: {
uid: "uid1",
url: "https://firebase.com"
},
Upload2: {
uid: "uid2",
url: "https://google.com"
}
},
users: {
uid1: {
name: "Purus"
},
uid2: {
name: "Frank"
}
}
}
We're taking a three-stepped approach here:
Load the data from uploads
Load the users for that data from users
Join the user data to the upload data
1. Load the data uploads
Your code is trying to return a value. Since the data is loaded from Firebase asynchronously, it won't be available yet when your return statement executes. That gives you two options:
Pass in a callback to getUploads() that you then call when the data has loaded.
Return a promise from getUploads() that resolves when the data has loaded.
I'm going to use promises here, since the code is already difficult enough.
function getUploads() {
return ref.child("uploads").once("value").then((snap) => {
return snap.val();
});
}
This should be fairly readable: we load all uploads and, once they are loaded, we return the value.
getUploads().then((uploads) => console.log(uploads));
Will print:
{
Upload1 {
uid: "uid1",
url: "https://firebase.com"
},
Upload2 {
uid: "uid2",
url: "https://google.com"
}
}
2. Load the users for that data from users
Now in the next step, we're going to be loading the user for each upload. For this step we're not returning the uploads anymore, just the user node for each upload:
function getUploads() {
return ref.child("uploads").once("value").then((snap) => {
var promises = [];
snap.forEach((uploadSnap) => {
promises.push(
ref.child("users").child(uploadSnap.val().uid).once("value")
);
});
return Promise.all(promises).then((userSnaps) => {
return userSnaps.map((userSnap) => userSnap.val());
});
});
}
You can see that we loop over the uploads and create a promise for loading the user for that upload. Then we return Promise.all(), which ensures its then() only gets called once all users are loaded.
Now calling
getUploads().then((uploads) => console.log(uploads));
Prints:
[{
name: "Purus"
}, {
name: "Frank"
}]
So we get an array of users, one for each upload. Note that if the same user had posted multiple uploads, you'd get that user multiple times in this array. In a real production app you'd want to de-duplicate the users. But this answer is already getting long enough, so I'm leaving that as an exercise for the reader...
3. Join the user data to the upload data
The final step is to take the data from the two previous steps and joining it together.
function getUploads() {
return ref.child("uploads").once("value").then((snap) => {
var promises = [];
snap.forEach((uploadSnap) => {
promises.push(
ref.child("users").child(uploadSnap.val().uid).once("value")
);
});
return Promise.all(promises).then((userSnaps) => {
var uploads = [];
var i=0;
snap.forEach((uploadSnap) => {
var upload = uploadSnap.val();
upload.username = userSnaps[i++].val().name;
uploads.push(upload);
});
return uploads;
});
});
}
You'll see we added a then() to the Promise.all() call, which gets invoked after all users have loaded. At that point we have both the users and their uploads, so we can join them together. And since we loaded the users in the same order as the uploads, we can just join them by their index (i). Once you de-duplicate the users this will be a bit trickier.
Now if you call the code with:
getUploads().then((uploads) => console.log(uploads));
It prints:
[{
uid: "uid1",
url: "https://firebase.com",
username: "Purus"
}, {
uid: "uid2",
url: "https://google.com",
username: "Frank"
}]
The array of uploads with the name of the user who created that upload.
The working code for each step is in https://jsbin.com/noyemof/edit?js,console
I did the following based on Franks answer and it works. I am not sure if this is the best way for dealing with large number of data.
getUploads() {
return new Promise((resolve, reject) => {
const rootDef = this.db.database.ref();
const uploadsRef = rootDef.child('userUploads').orderByChild('time');
const userRef = rootDef.child("userProfile");
var uploads = [];
uploadsRef.once("value").then((uploadSnaps) => {
uploadSnaps.forEach((uploadSnap) => {
var upload = uploadSnap.val();
userRef.child(uploadSnap.val().user).once("value").then((userSnap) => {
upload.displayName = userSnap.val().displayName;
upload.avatar = userSnap.val().avatar;
uploads.push(upload);
});
});
});
resolve(uploads);
});
}

MeteorJS Infinite loop when using meteor call and meteor method

I have a sample code that goes like this:
Client Helper:
getUsername: function (userId) {
Meteor.call("getUsername", userId, function (err, result) {
if(!err) {
Session.set("setUsername", result);
else {
console.log(err);
}
});
return Session.get("setUsername");
}
Server
Meteor.methods({
"getUsername": function (userId) {
var x = Meteor.users.find({_id: userId}, {fields: {username:1}}).fetch()[0];
return x.username;
}
});
The result of this code is an infinite loop of username passing to the client. Is there a way to stop the loop and pass only the data that is needed on the client? I believe the reactivity is causing the data to loop infinitely and I am not sure how to stop it. I tried using "reactive":false on my query in the server but it does not work.
If you want to access username everywhere in client templates (so thats why you put it into session), I would not set it in template helper. I would set it on startup and get username from session in template helpers (without calling server method)
If you need username just in one template, so you want to return its value from your template helper, do not put it into session, just return it in your server method callback.
Based on your sample code, I assume, you have a set of posts and you are retrieving user name based on user id for each post. Then instead of doing it this way, you should use publish composite package to publish related users as well.
Meteor.publishComposite('getPosts', function (postIds) {
return [{
find: function() {
return Posts.find({ _id: { $in: postIds }});
// you can also do -> return Posts.find();
// or -> return Posts.find({ /* or what ever your selector is to get the posts you need*/ });
},
children: [{
find: function(post) {
return Meteor.users.find({
id: post.userId //or the correct field in your post document to get user id
}, {
fields: {
"profile": 1
}
});
}
}}
}]
});
This way your publication will take care of publishing related users along with posts. You don't need to use methods and call them each time.

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