rudeshark.net/src/server/file/send-drive-file.ts
2018-05-04 17:59:51 +09:00

79 lines
2.2 KiB
TypeScript

import * as fs from 'fs';
import * as Koa from 'koa';
import * as send from 'koa-send';
import * as mongodb from 'mongodb';
import DriveFile, { getDriveFileBucket } from '../../models/drive-file';
import DriveFileThumbnail, { getDriveFileThumbnailBucket } from '../../models/drive-file-thumbnail';
const assets = `${__dirname}/../../server/file/assets/`;
const commonReadableHandlerGenerator = (ctx: Koa.Context) => (e: Error): void => {
console.error(e);
ctx.status = 500;
};
export default async function(ctx: Koa.Context) {
// Validate id
if (!mongodb.ObjectID.isValid(ctx.params.id)) {
ctx.throw(400, 'incorrect id');
return;
}
const fileId = new mongodb.ObjectID(ctx.params.id);
// Fetch drive file
const file = await DriveFile.findOne({ _id: fileId });
if (file == null) {
ctx.status = 404;
await send(ctx, `${__dirname}/assets/dummy.png`, { root: assets });
return;
}
if (file.metadata.deletedAt) {
ctx.status = 410;
if (file.metadata.isExpired) {
await send(ctx, `${__dirname}/assets/cache-expired.png`, { root: assets });
} else {
await send(ctx, `${__dirname}/assets/tombstone.png`, { root: assets });
}
return;
}
const sendRaw = async () => {
const bucket = await getDriveFileBucket();
const readable = bucket.openDownloadStream(fileId);
readable.on('error', commonReadableHandlerGenerator(ctx));
ctx.set('Content-Type', file.contentType);
ctx.body = readable;
};
if ('thumbnail' in ctx.query) {
// 画像以外
if (!file.contentType.startsWith('image/')) {
const readable = fs.createReadStream(`${__dirname}/assets/thumbnail-not-available.png`);
ctx.set('Content-Type', 'image/png');
ctx.body = readable;
} else if (file.contentType == 'image/gif') {
// GIF
await sendRaw();
} else {
const thumb = await DriveFileThumbnail.findOne({ 'metadata.originalId': fileId });
if (thumb != null) {
ctx.set('Content-Type', 'image/jpeg');
const bucket = await getDriveFileThumbnailBucket();
ctx.body = bucket.openDownloadStream(thumb._id);
} else {
await sendRaw();
}
}
} else {
if ('download' in ctx.query) {
ctx.set('Content-Disposition', 'attachment');
}
await sendRaw();
}
}