1 files changed, 51 insertions, 0 deletions
diff --git a/src/server/api/define.ts b/src/server/api/define.ts
new file mode 100644
index 0000000000..c66ade5fda
--- /dev/null
+++ b/src/server/api/define.ts
@@ -0,0 +1,51 @@
+import * as fs from 'fs';
+import { ILocalUser } from '../../models/user';
+import { IApp } from '../../models/app';
+import { IEndpointMeta } from './endpoints';
+
+type Params<T extends IEndpointMeta> = {
+	[P in keyof T['params']]: T['params'][P]['transform'] extends Function
+		? ReturnType<T['params'][P]['transform']>
+		: ReturnType<T['params'][P]['validator']['get']>[0];
+};
+
+export default function <T extends IEndpointMeta>(meta: T, cb: (params: Params<T>, user: ILocalUser, app: IApp, file?: any, cleanup?: Function) => Promise<any>): (params: any, user: ILocalUser, app: IApp, file?: any) => Promise<any> {
+	return (params: any, user: ILocalUser, app: IApp, file?: any) => {
+		function cleanup() {
+			fs.unlink(file.path, () => {});
+		}
+
+		if (meta.requireFile && file == null) return Promise.reject('file required');
+
+		const [ps, pserr] = getParams(meta, params);
+		if (pserr) {
+			if (file) cleanup();
+			return Promise.reject(pserr);
+		}
+
+		return cb(ps, user, app, file, cleanup);
+	};
+}
+
+function getParams<T extends IEndpointMeta>(defs: T, params: any): [Params<T>, Error] {
+	const x: any = {};
+	let err: Error = null;
+	Object.entries(defs.params).some(([k, def]) => {
+		const [v, e] = def.validator.get(params[k]);
+		if (e) {
+			err = new Error(e.message);
+			err.name = 'INVALID_PARAM';
+			(err as any).param = k;
+			return true;
+		} else {
+			if (v === undefined && def.default) {
+				x[k] = def.default;
+			} else {
+				x[k] = v;
+			}
+			if (def.transform) x[k] = def.transform(x[k]);
+			return false;
+		}
+	});
+	return [x, err];
+}