How dynamic add an array of functions to an javascript function?

Question

I do have this structure:

db.collection('users')

and want to make this:

db.collection('users')
   .where('works', 'array-contains', 'CASE_A')
   .where('works', 'array-contains', 'CASE_B')
   .where('works', 'array-contains', 'CASE_C')
   ...

In this case, I will make an array of
(( .where('works', 'array-contains',${variable}))

and i will add this in the beginning db.collection('users'), how can i make this?

I think you can use Javascript eval function and array join function. — TopW3, Jan 13 '20 at 02:21
If you want to write a query which contains ALL the cases, you will have to create a separate query for each case and merge the query results in your app. The following [article](https://medium.com/firebase-tips-tricks/how-to-combined-two-firestore-queries-to-simulate-a-logical-or-query-27d28a43cb2d) explains how to do that (disclaimer, I'm the author). — Renaud Tarnec, Jan 13 '20 at 16:03

Doug Stevenson · Answer 1 · 2020-01-13T02:57:39.413

2

Just make an inline array:

db.collection('users')
   .where('works', 'array-contains', ['CASE_A', 'CASE_B', 'CASE_C'])

Or use a variable if you want:

const array = ['CASE_A', 'CASE_B', 'CASE_C']
db.collection('users')
   .where('works', 'array-contains', array)

If you actually want to find documents where all cases are present (not where any of the cases are present), you won't be able to use an array-contains type query. You will have to convert your array into an object and query it as shown in this question: Firestore: Multiple 'array-contains'

edited Jan 13 '20 at 02:57

answered Jan 13 '20 at 02:21

Doug Stevenson

297,357
32
422
441

will this return a query which contains ALL the cases ? I want the documents where all cases match. – eeerrrttt Jan 13 '20 at 02:53
1

No, this will do a logical OR of each item. You can't do a logical AND of each item, as Firestore doesn't support multiple array-contains clauses in a single query. If you want to use an object instead of an array, use this: https://stackoverflow.com/questions/52837711/firestore-multiple-array-contains – Doug Stevenson Jan 13 '20 at 02:56

score 1 · Answer 2 · answered Jan 13 '20 at 02:27

Please try this code.

const makeItem = value => `.where('works', 'array-contains',${value}`

const arrFuncs = [
    makeItem('CASE_A'),
    makeItem('CASE_B'),
    makeItem('CASE_C'),
]

const initialCmd = `db.collection('users')`
eval(initialCmd + arrFuncs.join(''))

How dynamic add an array of functions to an javascript function?

2 Answers2