Add csv as an export type for rehearsal graph

[robostheimer]

Adding csv as an export type for rehearsal graph would make it easier to organize the data into spreadsheets which in turn will make it easier to track the migration progress. I believe that the json2csv library could be leveraged to make this happen.

[egorio]

Hi @robostheimer, this is a good idea. Would you mind to propose a format of file (columns) you would like to see?

[robostheimer]

I think the best case would be:
package name | external | file.name | file.hasTypes | file.edges.packageName | file.edges.hasTypes | file.edges.FileName.

Essentially just unwind the rehearsal graph json export and make it useable in spreadsheet format.

I plan to look into this myself if I can find the time.

[lynchbomb]

@robostheimer you could easily add type of formatter https://github.com/rehearsal-js/rehearsal-js/tree/master/packages/reporter/src/formatters

eg.

// packages/reporter/src/formatters/csv-formatter.ts

import { Parser } from '@json2csv/plainjs';
import { unwind } from '@json2csv/transforms';
import type { Report, FormatterBase } from '../types.js';

export class CSVFormatter implements FormatterBase {
  static extension = '.csv';
  static getReport(report: Report): string {
    const jsonData = JSON.stringify(report, null, 2);
    try {
      const opts = {
         transforms: [
           unwind({ paths: ['colors'] })
          ]
      };
      
     const parser = new Parser(opts);
     return parser.parse(jsonData);
    } catch (err) {
       // handle err
    }
  }
}