Airtable Script - Same Table Back Links

sameTableBacklinksButtonBatch.js

/*****************************************************************************************************
Name: Same Table Back Links
Date: July 9, 2021
Author: Kuovonne Vorderbruggen
Website: https://atmosphere.kuovonne.com

## Description
Create backlinks for a table with same-table linked records

## Usage
1. Copy and paste this script into Scripting App.
2. Click the "settings gear" for Scripting app and set the table and fields. No code changes necessary.
3. Click the "run" button for the script.

## license
This script is provided "as is", without warranty of any kind. Liability of the
author will be limited to a maximum of the original purchase price of the script.
The author will not be liable for any general, special, incidental, or consequential
damages.

*****************************************************************************************************
*/


/*******************************************************************************
  Script Configuration Settings
*******************************************************************************
*/
const inputConfig = input.config({
    title: 'Create back links for same-table links',
    items: [
        input.config.table('table', {
            label: 'Table with same-table links',
        }),
        input.config.field('fldLinkAuthority', {
            label: 'Original Link',
            description: 'This linked record field is the "source of truth" for links. Its values will not be changed.',
            parentTable: 'table',
        }),
        input.config.field('fldBackLink', {
            label: 'Back Link field',
            description: 'This linked record field will be updated to match information in the original link field.',
            parentTable: 'table',
        }),
    ]
});


/*******************************************************************************
  Main function for the script
*******************************************************************************
*/

await main()
output.markdown("## Done")

/*******************************************************************************/

async function main() {
    if (!checkSettings()) { return }
    const userContinue = await input.buttonsAsync(`Update backlinks in ${inputConfig.table.name}?`, ["Continue", "Cancel"])
    if (userContinue == "Cancel") {
        return
    }
    const queryResult = await inputConfig.table.selectRecordsAsync({fields: [
        inputConfig.fldLinkAuthority,
        inputConfig.fldBackLink,
    ]})
    output.markdown(`Records to examine: ${queryResult.records.length}`)
    // setup map of backlinks by recordId
    let linkMap = {}
    for (const record of queryResult.records) {
        const currentBacklinks = record.getCellValue(inputConfig.fldBackLink)
        linkMap[record.id] = {
            currentBacklinkIds: (currentBacklinks ? currentBacklinks.map(obj => obj.id) : []),
            newBacklinkIds: [], // to be filled in later in script
        }
    }
    // fill in newBacklinkIds
    for (const record of queryResult.records) {
        const linkedValue = record.getCellValue(inputConfig.fldLinkAuthority)
        if (!linkedValue) {continue}
        for (const obj of linkedValue) {
            linkMap[obj.id].newBacklinkIds.push(record.id)
        }
    }
    // figure out which records need updating
    let recordsToUpdate = []
    for (const recordId of Object.keys(linkMap)) {
        const currentBacklinkIds = linkMap[recordId].currentBacklinkIds
        const newBacklinkIds = linkMap[recordId].newBacklinkIds
        if ( (currentBacklinkIds.length == newBacklinkIds.length) && currentBacklinkIds.every(value => newBacklinkIds.includes(value))) {
            continue // this recordId doesn't need updating
        }
        recordsToUpdate.push({
            id: recordId,
            fields: {
                [inputConfig.fldBackLink.name]: newBacklinkIds.map(id => ({id: id}))
            }
        })
    }
    output.markdown(`Records to update: ${recordsToUpdate.length}`)
    while (recordsToUpdate.length > 0) {
        await inputConfig.table.updateRecordsAsync(recordsToUpdate.slice(0, 50));
        recordsToUpdate = recordsToUpdate.slice(50);
    }
}

/*******************************************************************************/

function checkSettings() {
    if (
        (inputConfig.fldLinkAuthority.type != "multipleRecordLinks")
        || (inputConfig.fldBackLink.type != "multipleRecordLinks")
        || (inputConfig.fldLinkAuthority.options.linkedTableId != inputConfig.table.id)
        || (inputConfig.fldBackLink.options.linkedTableId != inputConfig.table.id)
        || (inputConfig.fldBackLink.id == inputConfig.fldLinkAuthority.id)
    ) {
        output.markdown("Check fields in settings.")
        return false
    }
    return true
}
/*******************************************************************************
END OF SCRIPT
*******************************************************************************
*/