5 files changed, 128 insertions, 65 deletions
diff --git a/src/misc/create-temp.ts b/src/misc/create-temp.ts
new file mode 100644
index 0000000000..04604cf7d0
--- /dev/null
+++ b/src/misc/create-temp.ts
@@ -0,0 +1,10 @@
+import * as tmp from 'tmp';
+
+export function createTemp(): Promise<[string, any]> {
+	return new Promise<[string, any]>((res, rej) => {
+		tmp.file((e, path, fd, cleanup) => {
+			if (e) return rej(e);
+			res([path, cleanup]);
+		});
+	});
+}
diff --git a/src/misc/detect-mine.ts b/src/misc/detect-mine.ts
new file mode 100644
index 0000000000..bbf49efc10
--- /dev/null
+++ b/src/misc/detect-mine.ts
@@ -0,0 +1,31 @@
+import * as fs from 'fs';
+import fileType from 'file-type';
+import checkSvg from '../misc/check-svg';
+
+export 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) {
+					if (type.mime == 'application/xml' && checkSvg(path)) {
+						res(['image/svg+xml', 'svg']);
+					} else {
+						res([type.mime, type.ext]);
+					}
+				} else if (checkSvg(path)) {
+					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]);
+			});
+	});
+}
diff --git a/src/misc/detect-url-mine.ts b/src/misc/detect-url-mine.ts
new file mode 100644
index 0000000000..eef64cfc56
--- /dev/null
+++ b/src/misc/detect-url-mine.ts
@@ -0,0 +1,15 @@
+import { createTemp } from './create-temp';
+import { downloadUrl } from './donwload-url';
+import { detectMine } from './detect-mine';
+
+export async function detectUrlMine(url: string) {
+	const [path, cleanup] = await createTemp();
+
+	try {
+		await downloadUrl(url, path);
+		const [type] = await detectMine(path);
+		return type;
+	} finally {
+		cleanup();
+	}
+}
diff --git a/src/misc/donwload-url.ts b/src/misc/donwload-url.ts
new file mode 100644
index 0000000000..0dd4e4ef5d
--- /dev/null
+++ b/src/misc/donwload-url.ts
@@ -0,0 +1,61 @@
+import * as fs from 'fs';
+import * as URL from 'url';
+import * as request from 'request';
+import config from '../config';
+import chalk from 'chalk';
+import Logger from '../services/logger';
+
+export async function downloadUrl(url: string, path: string) {
+	const logger = new Logger('download-url');
+
+	await new Promise((res, rej) => {
+		logger.info(`Downloading ${chalk.cyan(url)} ...`);
+
+		const writable = fs.createWriteStream(path);
+
+		writable.on('finish', () => {
+			logger.succ(`Download finished: ${chalk.cyan(url)}`);
+			res();
+		});
+
+		writable.on('error', error => {
+			logger.error(`Download failed: ${chalk.cyan(url)}: ${error}`, {
+				url: url,
+				e: 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.userAgent
+			}
+		});
+
+		req.pipe(writable);
+
+		req.on('response', response => {
+			if (response.statusCode !== 200) {
+				logger.error(`Got ${response.statusCode} (${url})`);
+				writable.close();
+				rej(response.statusCode);
+			}
+		});
+
+		req.on('error', error => {
+			logger.error(`Failed to start download: ${chalk.cyan(url)}: ${error}`, {
+				url: url,
+				e: error
+			});
+			writable.close();
+			rej(error);
+		});
+
+		logger.succ(`Downloaded to: ${path}`);
+	});
+}
diff --git a/src/misc/download-text-file.ts b/src/misc/download-text-file.ts
index 60c9d83da9..f73286e9bb 100644
--- a/src/misc/download-text-file.ts
+++ b/src/misc/download-text-file.ts
@@ -1,79 +1,25 @@
-import * as tmp from 'tmp';
 import * as fs from 'fs';
 import * as util from 'util';
-import chalk from 'chalk';
-import * as request from 'request';
 import Logger from '../services/logger';
-import config from '../config';
+import { createTemp } from './create-temp';
+import { downloadUrl } from './donwload-url';
 
 const logger = new Logger('download-text-file');
 
 export async function downloadTextFile(url: string): Promise<string> {
 	// 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]);
-		});
-	});
+	const [path, cleanup] = await createTemp();
 
 	logger.info(`Temp file is ${path}`);
 
-	// write content at URL to temp file
-	await new Promise((res, rej) => {
-		logger.info(`Downloading ${chalk.cyan(url)} ...`);
+	try {
+		// write content at URL to temp file
+		await downloadUrl(url, path);
 
-		const writable = fs.createWriteStream(path);
+		const text = await util.promisify(fs.readFile)(path, 'utf8');
 
-		writable.on('finish', () => {
-			logger.succ(`Download finished: ${chalk.cyan(url)}`);
-			res();
-		});
-
-		writable.on('error', error => {
-			logger.error(`Download failed: ${chalk.cyan(url)}: ${error}`, {
-				url: url,
-				e: error
-			});
-			rej(error);
-		});
-
-		const requestUrl = new URL(url).pathname.match(/[^\u0021-\u00ff]/) ? encodeURI(url) : url;
-
-		const req = request({
-			url: requestUrl,
-			proxy: config.proxy,
-			timeout: 10 * 1000,
-			headers: {
-				'User-Agent': config.userAgent
-			}
-		});
-
-		req.pipe(writable);
-
-		req.on('response', response => {
-			if (response.statusCode !== 200) {
-				logger.error(`Got ${response.statusCode} (${url})`);
-				writable.close();
-				rej(response.statusCode);
-			}
-		});
-
-		req.on('error', error => {
-			logger.error(`Failed to start download: ${chalk.cyan(url)}: ${error}`, {
-				url: url,
-				e: error
-			});
-			writable.close();
-			rej(error);
-		});
-	});
-
-	logger.succ(`Downloaded to: ${path}`);
-
-	const text = await util.promisify(fs.readFile)(path, 'utf8');
-
-	cleanup();
-
-	return text;
+		return text;
+	} finally {
+		cleanup();
+	}
 }