README.md

Oak Middleware Validator

Oak middleware for parameter and body validator

Usage

• As a router middleware

  import { validatorMiddleware, ValidatorMiddlewareOptions } from "https://raw.githubusercontent.com/halvardssm/oak-middleware-validator/master/mod.ts"
  import { RouterMiddleware } from "https://deno.land/x/oak/mod.ts";
  
  const router = new Router();
  
  const app = new Application();
  
  const options: ValidatorMiddlewareOptions = {
    validations: [
      { key: "a", validationOption: "string", isUrlParam: true },
      { key: "b", validationOption: "b", isOptional: true },
      { key: "c", validationOption: validateStringIn("b") },
      { key: "d", validationOption: validateIsNumber(0, 1) },
    ],
    bodyRequired: true,
    errorMessages: {
      ERROR_NO_BODY: "Custom message"
    }
  }
  
  router
    .get("/bar", validatorMiddleware(options),...)
  
  app.use(router.routes());
  
  await app.listen(appOptions);

Options

• validations: ValidationT[]; // Array of validations
• bodyRequired?: boolean; // If true, will return error if body is empty
• bodyType?: BodyType; // Will validate the body against a provided body type
• errorMessages?: Partial; // Customize your own error messages

validationT

• key: string; // The key
• validationOption: ValidationFn | string; // The validation function, also accepts a typeof or a string to compare strings
• isOptional?: boolean; // Will allow the key to be missing
• isUrlParam?: boolean; // Will check the url instead of the body

errorMessagesT

• ERROR_NO_BODY: "No body was provided",
• ERROR_INVALID_BODY: "Invalid body type",
• ERROR_MISSING_REQUIRED: "No value was provided",
• ERROR_VALIDATION_FAILED: "Validation failed",
• ERROR_NOT_IN_ARRAY: "Value not in array",
• ERROR_NUMBER_MIN: "Value is smaller than the allowed size",
• ERROR_NUMBER_MAX: "Value is larger than the allowed size"

validationFn

(
  key: string, // The key
  value: string | Uint8Array, // The value
  validationError: ValidationErrorFn, // The validation error callback
  errorMessages: ErrorMessagesT, // Exposes the error messages
  options: ValidatorMiddlewareOptions // Exposes the options
) => void

Available validation methods

• validateStringInArray(...values: string[]) // Checks if the value is in the array
• validateIsNumber(min?: number, max?: number, radix?: number) // Checks if the value is a number, and if min/max is given it compares them inclusively

Contributing

All contributions are welcome, make sure to read the contributing guidelines.

Uses

• Oak