Check if the query is already executed and resolved

[samislam]

I have the following code:

const query = UserModel.find({})
const resolvedValue = await query

I want to check if the query was executed, how do I check that? is there something like the following I can use in mongoose?

console.log(query.resolved) // false or true
// or
console.log(query.awaited) // false or true
// or
console.log(query.executed) // false or true

I know that I can simply see if the variable resolvedValue is not undefined, but I want to check if there's such an option in mongoose, which would be pretty handy if it exists.

[vkarpov15]

There isn't a good publicly facing way to do this, other than to await query and see if that throws an error.

Why are you looking to check whether a given query has already been executed?

[samislam]

Because I have written a package called setDoc, and the way I was planning to make it is:
it requires the user to write a function which accepts two types as the first argument, and a second argument which is the options argument:

• function.
• asyncfunction.
  The consumer of the function will use it as follows;

setDocMw( ()=> Model.find(), { options } )
// or for example
setDocMw( async (req)=> (await getModelById(req.body.recipient)).findById(req.params.id), {
pre: (query)=> query.sort() // used to chain methods on the query before it gets awaited
} )

That's how it looks like from the perspective of the consumer of the package,
but from inside. when a user provides an async function as the first argument, I must await that async function to receive the query (the returned value from the async function).
However, awaiting the async function awaits the query, (why? so strange...)

I should await the query, because I need the query to chain some methods on it,
for instance, the pre option is used for that, and in order for me (the developer) to pass the argument query as the first parameter to the pre option method, I need to have the query, not the resolved documents.

and the only way I found to achieve this pattern is by having an option like query.isResolved? or query.isAwaited or query.isExecuted.

I have written the package however, I wanted at first to have that pre/post options, but it did not work, so I have chosen another pattern for that.

The package is on npm as well as github

[vkarpov15]

The workaround is to return { query } instead of return query from an async function. Because Mongoose queries have a then() function, returning a query from an async function automatically executes the query. Does that work for you?

[samislam]

yes, that's right.

[samislam]

I'll make a request for a new feature for this, however, ok?

[vkarpov15]

I'm not sure how the new feature would work. The only option would be to remove the then() function from Mongoose queries, which would drop support for promise chaining and async/await. And we won't do that.