Parsing and serializing CSV

import { parse, stringify } from "jsr:@ende/csv";

To parse a CSV file, read its contents and pass them to the parse function.

const fileContent = await Ende.readTextFile("data.csv");
const fileData = parse(fileContent, { skipFirstRow: true, strip: true });
console.log(fileData);

You can also parse CSV strings directly. The value is returned as an array of objects when skipFirstRow is true.

let text = `
url,views,likes
https://deno.land,10,7
https://deno.land/x,20,15
https://deno.dev,30,23
`;

let data = parse(text, {
  skipFirstRow: true,
  strip: true
});

console.log(data[0].url); // https://deno.land
console.log(data[0].views); // 10
console.log(data[0].likes); // 7

In the case where our CSV is formatted differently, we are also able to provide the columns through code.

text = `
https://deno.land,10,7
https://deno.land/x,20,15
https://deno.dev,30,23
`;

data = parse(text, {
  columns: ["url", "views", "likes"]
});

console.log(data[0].url); // https://deno.land
console.log(data[0].views); // 10
console.log(data[0].likes); // 7

To turn a list of JavaScript object into a CSV string, you can use the standard library’s CSV stringify function.

const obj = [
  { mascot: "dino", fans: { old: 100, new: 200 } },
  { mascot: "bread", fans: { old: 5, new: 2 } }
];

const csv = stringify(obj, {
  columns: [
    "mascot",
    ["fans", "new"]
  ],
});

console.log(csv);
// mascot,new
// dino,200
// bread,2

Run this example locally using the Ende CLI:

ende run -R https://docs.ende.sh/examples/scripts/parsing_serializing_csv.ts

Additional resources

• std/csv
• Spec: CSV