如何使用JavaScript有条件地将过滤器应用于Firestore查询

Question

I put in some breaks, and I can see that my if statement is being hit correctly, but the return data is not taking the additional where clause into account. Basically if it's the start month I don't want it to have a starting point, and just return any that are not complete. After that I want it to just pull back a month at a time.

I've also verified my date values are correct.

let endDate = moment(date).add(1, 'M').toDate()
var search = fb.ledgersCollection.where('accountId', '==', this.account.id)
                    .where('completed', '==', false)
                    .where('date', '<', endDate)


if(date != this.startDate) {
    search.where('date', '>', date)
}

search.orderBy('date', 'asc').orderBy('deposit', 'desc').orderBy('name', 'asc').get().then(docs => {

    docs.forEach(doc => {

        let ledger = doc.data()
        ledger.date = new Date(1000* doc.data().date.seconds)
        ledger.id = doc.id
        this.currentBalance = parseFloat(Number(this.currentBalance) + Number(ledger.amount)).toFixed(2)
        ledger.balance = this.currentBalance
        this.ledgerItems.push(ledger)
    })
})

Answer 1

Query objects in Firestore are immutable, meaning they can't be modified after being created. What you need to do is build a new query upon a prior query. For example:

var search = fb.ledgersCollection.where('accountId', '==', this.account.id)
                    .where('completed', '==', false)
                    .where('date', '<', endDate)


if(date != this.startDate) {
    // build a new query based off the original query
    search = search.where('date', '>', date)
}

Note here that I'm reassigning search to a new query object built upon the original search. This new search will apply all of the filters at the same time.