monkeeShark/src/server/proxy/proxy-media.ts
2019-02-07 21:02:33 +09:00

117 lines
2.6 KiB
TypeScript

import * as fs from 'fs';
import * as URL from 'url';
import * as tmp from 'tmp';
import * as Koa from 'koa';
import * as request from 'request';
import * as fileType from 'file-type';
import * as isSvg from 'is-svg';
import { serverLogger } from '..';
import config from '../../config';
import { IImage, ConvertToPng } from '../../services/drive/image-processor';
export async function proxyMedia(ctx: Koa.BaseContext) {
const url = 'url' in ctx.query ? ctx.query.url : 'https://' + ctx.params.url;
// Create temp file
const [path, cleanup] = await new Promise<[string, any]>((res, rej) => {
tmp.file((e, path, fd, cleanup) => {
if (e) return rej(e);
res([path, cleanup]);
});
});
try {
await fetch(url, path);
const [type, ext] = await detectMine(path);
let image: IImage;
if ('static' in ctx.query && ['image/png', 'image/gif'].includes(type)) {
image = await ConvertToPng(path, 498, 280);
} else {
image = {
data: fs.readFileSync(path),
ext,
type,
};
}
ctx.set('Content-Type', type);
ctx.set('Cache-Control', 'max-age=31536000, immutable');
ctx.body = image.data;
} catch (e) {
serverLogger.error(e);
if (typeof e == 'number' && e >= 400 && e < 500) {
ctx.status = e;
} else {
ctx.status = 500;
}
} finally {
cleanup();
}
}
async function fetch(url: string, path: string) {
await new Promise((res, rej) => {
const writable = fs.createWriteStream(path);
writable.on('finish', () => {
res();
});
writable.on('error', error => {
rej(error);
});
const requestUrl = URL.parse(url).pathname.match(/[^\u0021-\u00ff]/) ? encodeURI(url) : url;
const req = request({
url: requestUrl,
proxy: config.proxy,
timeout: 10 * 1000,
headers: {
'User-Agent': config.user_agent
}
});
req.pipe(writable);
req.on('response', response => {
if (response.statusCode !== 200) {
writable.close();
rej(response.statusCode);
}
});
req.on('error', error => {
writable.close();
rej(error);
});
});
}
async function detectMine(path: string) {
return new Promise<[string, string]>((res, rej) => {
const readable = fs.createReadStream(path);
readable
.on('error', rej)
.once('data', (buffer: Buffer) => {
readable.destroy();
const type = fileType(buffer);
if (type) {
res([type.mime, type.ext]);
} else if (isSvg(buffer)) {
res(['image/svg+xml', 'svg']);
} else {
// 種類が同定できなかったら application/octet-stream にする
res(['application/octet-stream', null]);
}
})
.on('end', () => {
// maybe 0 bytes
res(['application/octet-stream', null]);
});
});
}