@nestjs/common/pipes/file/file-type.validator.js

Nest - modern, fast, powerful node.js web framework (@common)

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.FileTypeValidator = void 0;
const file_validator_interface_1 = require("./file-validator.interface");
/**
 * Defines the built-in FileType File Validator. It validates incoming files mime-type
 * matching a string or a regular expression. Note that this validator uses a naive strategy
 * to check the mime-type and could be fooled if the client provided a file with renamed extension.
 * (for instance, renaming a 'malicious.bat' to 'malicious.jpeg'). To handle such security issues
 * with more reliability, consider checking against the file's [magic-numbers](https://en.wikipedia.org/wiki/Magic_number_%28programming%29)
 *
 * @see [File Validators](https://docs.nestjs.com/techniques/file-upload#validators)
 *
 * @publicApi
 */
class FileTypeValidator extends file_validator_interface_1.FileValidator {
    buildErrorMessage() {
        return `Validation failed (expected type is ${this.validationOptions.fileType})`;
    }
    isValid(file) {
        if (!this.validationOptions) {
            return true;
        }
        return (!!file &&
            'mimetype' in file &&
            !!file.mimetype.match(this.validationOptions.fileType));
    }
}
exports.FileTypeValidator = FileTypeValidator;