DefinitelyTyped/types/multer/index.d.ts

// Type definitions for multer 1.3
// Project: https://github.com/expressjs/multer
// Definitions by: jt000 <https://github.com/jt000>
//                 vilicvane <https://vilic.github.io/>
//                 David Broder-Rodgers <https://github.com/DavidBR-SW>
//                 Michael Ledin <https://github.com/mxl>
//                 HyunSeob Lee <https://github.com/hyunseob>
// Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
// TypeScript Version: 2.1

import * as express from 'express';

declare namespace multer {
    interface Field {
        /** The field name. */
        name: string;
        /** Optional maximum number of files per field to accept. */
        maxCount?: number;
    }

    interface Options {
        /** The destination directory for the uploaded files. */
        dest?: string;
        /** The storage engine to use for uploaded files. */
        storage?: StorageEngine;
        /** An object specifying the size limits of the following optional properties. This object is passed to busboy
         * directly, and the details of properties can be found on https://github.com/mscdex/busboy#busboy-methods
         */
        limits?: {
            /** Max field name size (Default: 100 bytes) */
            fieldNameSize?: number;
            /** Max field value size (Default: 1MB) */
            fieldSize?: number;
            /** Max number of non- file fields (Default: Infinity) */
            fields?: number;
            /** For multipart forms, the max file size (in bytes)(Default: Infinity) */
            fileSize?: number;
            /** For multipart forms, the max number of file fields (Default: Infinity) */
            files?: number;
            /** For multipart forms, the max number of parts (fields + files)(Default: Infinity) */
            parts?: number;
            /** For multipart forms, the max number of header key=> value pairs to parse Default: 2000(same as node's http). */
            headerPairs?: number;
            /** Keep the full path of files instead of just the base name (Default: false) */
            preservePath?: boolean;
        };
        /** A function to control which files to upload and which to skip. */
        fileFilter?(req: Express.Request, file: Express.Multer.File, callback: (error: Error | null, acceptFile: boolean) => void): void;
    }

    interface StorageEngine {
        _handleFile(req: express.Request, file: Express.Multer.File, callback: (error?: any, info?: Partial<Express.Multer.File>) => void): void;
        _removeFile(req: express.Request, file: Express.Multer.File, callback: (error: Error) => void): void;
    }

    interface DiskStorageOptions {
        /** A function used to determine within which folder the uploaded files should be stored. Defaults to the system's default temporary directory. */
        destination?: string | ((req: Express.Request, file: Express.Multer.File, callback: (error: Error | null, destination: string) => void) => void);
        /** A function used to determine what the file should be named inside the folder. Defaults to a random name with no file extension. */
        filename?(req: Express.Request, file: Express.Multer.File, callback: (error: Error | null, filename: string) => void): void;
    }

    interface Instance {
        /** In case you need to handle a text-only multipart form, you can use any of the multer methods (.single(), .array(), fields()), req.body contains the text fields */
        /** Accept a single file with the name fieldName. The single file will be stored in req.file. */
        single(fieldName?: string): express.RequestHandler;
        /** Accept an array of files, all with the name fieldName. Optionally error out if more than maxCount files are uploaded. The array of files will be stored in req.files. */
        array(fieldName: string, maxCount?: number): express.RequestHandler;
        /** Accept a mix of files, specified by fields. An object with arrays of files will be stored in req.files. */
        fields(fields: Field[]): express.RequestHandler;
        /** Accepts all files that comes over the wire. An array of files will be stored in req.files. */
        any(): express.RequestHandler;
    }
}

interface Multer {
    (options?: multer.Options): multer.Instance;

    /* The disk storage engine gives you full control on storing files to disk. */
    diskStorage(options: multer.DiskStorageOptions): multer.StorageEngine;
    /* The memory storage engine stores the files in memory as Buffer objects. */
    memoryStorage(): multer.StorageEngine;
}

declare const multer: Multer;

export = multer;

declare global {
    namespace Express {
        interface Request {
            file: Multer.File;
            files: {
                [fieldname: string]: Multer.File[];
            } | Multer.File[];
        }

        namespace Multer {
            interface File {
                /** Field name specified in the form */
                fieldname: string;
                /** Name of the file on the user's computer */
                originalname: string;
                /** Encoding type of the file */
                encoding: string;
                /** Mime type of the file */
                mimetype: string;
                /** Size of the file in bytes */
                size: number;
                /** The folder to which the file has been saved (DiskStorage) */
                destination: string;
                /** The name of the file within the destination (DiskStorage) */
                filename: string;
                /** Location of the uploaded file (DiskStorage) */
                path: string;
                /** A Buffer of the entire file (MemoryStorage) */
                buffer: Buffer;
            }
        }
    }
}