How do I copy entries from one collection to another using mongoose? - node.js

Question

I'm trying to create a little task management site for a work project. The overall goal is here is that the tasks stay the same each month (their status can be updated and whatnot), and they need to be duplicated at the start of each new month so they can be displayed and sorted by on a table.
I already figured out how to schedule the task, I have the table I need set up. A little explanation before the code - the way I'm planning on doing this is having two different task collections - one I've called "assignments", will have the tasks that need to be duplicated (with their description, status and other necessary data) and another collection, which I called "tasks", will have the exact same data but with an additional "date" field. This is where the table will get it's data from, the date is just for sorting purposes.
This is what I have so far -
Index.js: gets all the assignments from the database, and sends the object over to the duplicate function.
router.get('/test', async function(req, res, next) {
let allTasks = await dbModule.getAllAssignments();
let result = await dbModule.duplicateTasks(allTasks);
res.json(result);
});
dbmodule.js:
getAllAssignments: () => {
allAssignments = Assignment.find({});
return allAssignments;
},
duplicateTasks: (allTasksToAdd) => {
try {
for (let i = 0; i < allTasksToAdd.length; i++) {
let newTask = new Task({
customername: allTasksToAdd.customername,
provname: allTasksToAdd.provname,
description: allTasksToAdd.description,
status: allTasksToAdd.status,
date: "07-2020"
})
newTask.save();
}
return "Done"
} catch (error) {
return "Error"
}
}
The issue arises when I try and actually duplicate the tasks. For testing purposes I've entered the date manually this time, but that's all that ends up being inserted - just the date, the rest of the data is skipped. I've heard of db.collection.copyTo(), but I'm not sure if it'll allow me to insert the field I need or if it's supported in mongoose. I know there's absolutely an easier way to do this but I can't quite figure it out. I'd love some input and suggestions if anyone has any.
Thanks.

Answer 1

The problem is that allTasksToAdd.customername (and the other fields your trying to access) will be undefined. You need to access the fields under the current index:
let newTask = new Task({
customername: allTasksToAdd[i].customername,
provname: allTasksToAdd[i].provname,
description: allTasksToAdd[i].description,
status: allTasksToAdd[i].status,
date: "07-2020"
})
Note that you can simplify this by using a for .. of loop instead:
for (const task of allTasksToAdd) {
const newTask = new Task({
customername: task.customername,
provname: task.provname,
description: task.description,
status: task.status,
date: "07-2020"
});
newTask.save();
}