holidays-jp-gen/dist/core.js

A CLI tool to generate lightweight TypeScript holiday data modules for Japan based on official government CSV data.

import fs from "node:fs";
import https from "node:https";
import path from "node:path";
import { fileURLToPath } from "node:url";
import { parse } from "csv-parse/sync";
import iconv from "iconv-lite";
const __filename = fileURLToPath(import.meta.url);
const __dirname = path.dirname(__filename);
const HOLIDAY_CSV_URL = "https://www8.cao.go.jp/chosei/shukujitsu/syukujitsu.csv";
export async function downloadCsv() {
    return new Promise((resolve, reject) => {
        https.get(HOLIDAY_CSV_URL, (res) => {
            const chunks = [];
            res.on("data", (chunk) => chunks.push(chunk));
            res.on("end", () => resolve(Buffer.concat(chunks)));
            res.on("error", reject);
        });
    });
}
export function parseCsv(buffer) {
    const utf8Str = iconv.decode(buffer, "Shift_JIS");
    const records = parse(utf8Str, {
        columns: true,
        skip_empty_lines: true,
    });
    return records.map((r) => ({
        date: r.国民の祝日・休日月日,
        name: r.国民の祝日・休日名称,
    }));
}
export function generateTs(holidays, fromYear) {
    const holidays_str = filterAndFormat(holidays, fromYear)
        .map((v) => `  ${v}`)
        .join("\n");
    // テンプレートファイルを読み込み
    const templatePath = path.join(__dirname, "templates", "functions.ts");
    const templateCode = fs.readFileSync(templatePath, "utf-8");
    // 空のholidaysオブジェクトを実データで置換
    const generatedCode = templateCode.replace("export const holidays: { [key: string]: string } = {};", `export const holidays: { [key: string]: string } = {\n${holidays_str}\n};`);
    return `// holidays-jp-from-${fromYear}.ts\n${generatedCode}`;
}
export function filterAndFormat(holidays, fromYear) {
    return holidays
        .filter((h) => {
        const y = Number(h.date.split("/")[0]);
        return y >= fromYear;
    })
        .map((h) => {
        const [y, m, d] = h.date.split("/");
        const mm = m.padStart(2, "0");
        const dd = d.padStart(2, "0");
        return `"${y}-${mm}-${dd}": "${h.name}",`;
    });
}