internet-programming/lab3/node_modules/json-server/lib/cli/utils/load.js

69 lines
2.0 KiB
JavaScript

"use strict";
const fs = require('fs');
const path = require('path');
const http = require('http');
const https = require('https');
const low = require('lowdb');
const FileAsync = require('lowdb/adapters/FileAsync');
const Memory = require('lowdb/adapters/Memory');
const is = require('./is');
const chalk = require('chalk');
const example = {
posts: [{
id: 1,
title: 'json-server',
author: 'typicode'
}],
comments: [{
id: 1,
body: 'some comment',
postId: 1
}],
profile: {
name: 'typicode'
}
};
module.exports = function (source) {
return new Promise((resolve, reject) => {
if (is.FILE(source)) {
if (!fs.existsSync(source)) {
console.log(chalk.yellow(` Oops, ${source} doesn't seem to exist`));
console.log(chalk.yellow(` Creating ${source} with some default data`));
console.log();
fs.writeFileSync(source, JSON.stringify(example, null, 2));
}
resolve(low(new FileAsync(source)));
} else if (is.URL(source)) {
// Normalize the source into a URL object.
const sourceUrl = new URL(source);
// Pick the client based on the protocol scheme
const client = sourceUrl.protocol === 'https:' ? https : http;
client.get(sourceUrl, res => {
let dbData = '';
res.on('data', data => {
dbData += data;
});
res.on('end', () => {
resolve(low(new Memory()).setState(JSON.parse(dbData)));
});
}).on('error', error => {
return reject(error);
});
} else if (is.JS(source)) {
// Clear cache
const filename = path.resolve(source);
delete require.cache[filename];
const dataFn = require(filename);
if (typeof dataFn !== 'function') {
throw new Error('The database is a JavaScript file but the export is not a function.');
}
// Run dataFn to generate data
const data = dataFn();
resolve(low(new Memory()).setState(data));
} else {
throw new Error(`Unsupported source ${source}`);
}
});
};