budibase/packages/server/src/utilities/csvParser.js

77 lines
1.9 KiB
JavaScript

const csv = require("csvtojson")
const { FieldTypes } = require("../constants")
const VALIDATORS = {
[FieldTypes.STRING]: () => true,
[FieldTypes.OPTIONS]: () => true,
[FieldTypes.NUMBER]: attribute => !isNaN(Number(attribute)),
[FieldTypes.DATETIME]: attribute => !isNaN(new Date(attribute).getTime()),
}
const PARSERS = {
[FieldTypes.NUMBER]: attribute => Number(attribute),
[FieldTypes.DATETIME]: attribute => new Date(attribute).toISOString(),
}
function parse(csvString, parsers) {
const result = csv().fromString(csvString)
const schema = {}
return new Promise((resolve, reject) => {
result.on("header", headers => {
for (let header of headers) {
schema[header] = {
type: parsers[header] ? parsers[header].type : "string",
success: true,
}
}
})
result.subscribe(row => {
// For each CSV row parse all the columns that need parsed
for (let key in parsers) {
if (!schema[key] || schema[key].success) {
// get the validator for the column type
const validator = VALIDATORS[parsers[key].type]
try {
// allow null/undefined values
schema[key].success = !row[key] || validator(row[key])
} catch (err) {
schema[key].success = false
}
}
}
})
result.on("done", error => {
if (error) {
console.error(error)
reject(error)
}
resolve(schema)
})
})
}
async function transform({ schema, csvString }) {
const colParser = {}
for (let key in schema) {
colParser[key] = PARSERS[schema[key].type] || schema[key].type
}
try {
const json = await csv({ colParser }).fromString(csvString)
return json
} catch (err) {
console.error(`Error transforming CSV to JSON for data import`, err)
throw err
}
}
module.exports = {
parse,
transform,
}