Parsing and serializing CSV

CSV is a data serialization format that is designed to be portable for table-like applications.

import { parse, stringify } from "https://deno.land/std@0.207.0/csv/mod.ts";

To parse a CSV string, you can use the the standard library's CSV parse function. The value is returned as a JavaScript object.

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 Deno CLI:

deno run https://examples.deno.land/parsing-serializing-csv.ts

Additional resources:

Parsing and serializing YAML Hex and Base64 Encoding