使用ExpressJ在MongoDB中获取数据请求

Question

I am new to nodejs/web app and I am trying to get data out from MongoDB. My mongoDB has documents under collection "a"

{_id:("1"), "Question":"mcq1", "Answer":"one", "Keyword":"CLASS"}
{_id:("2"), "Question":"mcq2", "Answer":"two", "Keyword":"CLASS"}
{_id:("3"), "Question":"mcq3", "Answer":"three", "Keyword":"OVERLOAD"}
{_id:("4"), "Question":"mcq4", "Answer":"four", "Keyword":"OODP"}

I want to extract the data "Question": field_value, "Answer":field_value out using nodejs -> expressjs through a button and textbox form using the unique Keyword and to be displayed in a table form as below.

<tr>
<td><%= Question %></td>
<td><%= Answer %> </td>
</tr>

I have been able to get what i want with the monogodb shell using

db.a.find({"Keyword":CLASS},{"Question":1,"Answer":1,_id:0})

Currently the textbox and button onclick codes are below.

Input Keyword to search: <input type="text" id="searchBtn" value="">
<button type="button" onclick="alert(document.getElementById('searchBtn').value)">Click me!</button>

How can i extract the Question and Answer with the button click?
Using db.a.find({"Keyword":CLASS},{"Question":1,"Answer":1,_id:0}) i want to get a table in the form of

Question, Answer,Keyword
mcq1, one, CLASS
mcq2, two, CLASS

Answer 1

If you do a db query based on that keyword you'll get the occurrences in mongo, so you can do a form(GET/POST) field with the input and the button you already have. This will be caught in your express code as a route, there you can implement some basic code filling your search needs and the return value will be some simple data or an array if multiple match.

This is a basic search that one user (Miqe) once taught me here, first you need the query (or you can just put directly there) and later search in the mongo. But pay attention that your callback function will return the result, here is just a console.log() after returning the values you can assign them to a variable and pass through a template engine rendering in the html in the desire format.

query = {username: username, password: password}
dbo.collection('Users').find(query, function(err, user){
  if(err) throw new Error(err);
  if(!user) 
    console.log('Not found');
  else 
    console.log('Found!');

})

Here is just the code to find in a collection named Users, you still need to join with the route and do a connection to the DB.

I'll leave a link who helped me a lot! The mongo documentation is still a good start too. https://www.w3schools.com/nodejs/nodejs_mongodb_query.asp