Package 'httpproblems'

Describe a Problem with an HTTP Request

Description

http_problem() creates the "Problem Details" structure defined in RFC 7807, used for reporting errors from HTTP APIs in a standard way.

There are also helper methods for the most common HTTP problems: HTTP 400 Bad Request, 404 Not Found, 401 Unauthorized, 403 Forbidden, 409 Conflict, and 500 Internal Server Error.

Usage

http_problem(
  detail = NULL,
  status = 500L,
  type = NULL,
  title = NULL,
  instance = NULL,
  ...
)

bad_request(detail = NULL, instance = NULL, ...)

unauthorized(detail = NULL, instance = NULL, ...)

forbidden(detail = NULL, instance = NULL, ...)

not_found(detail = NULL, instance = NULL, ...)

conflict(detail = NULL, instance = NULL, ...)

internal_server_error(detail = NULL, instance = NULL, ...)

Arguments

detail	A human-readable string giving more detail about the error, if possible.
status	The HTTP status code appropriate for the response.
type	A URL pointing to human-readable documentation for this type of problem. When NULL, the type is generated based on the status code; see http_problem_types() for a list of the defaults.
title	A "short, human-readable summary of the problem type". When NULL, the title is generated based on the status code; see http_problem_types() for a list of the defaults.
instance	A URL that identifies the specific occurrence of the problem, if possible. When NULL this field is simply excluded.
...	Additional fields added to the problem as Extension Members.

Value

An object of class "http_problem", which has fields corresponding to an RFC 7807 Problem Details structure.

See Also

stop_for_http_problem for issuing R errors with these structures.

Examples

body <- bad_request("Parameter 'id' must be a number.")
str(body)

---

List Built-In Problem Types

Description

Many APIs will not need to define custom problem "types", since HTTP status codes are usually illustrative enough. This function lists the default type and title information for a given status code.

Usage

http_problem_types()

Value

A data frame of HTTP status codes and their default title & type.

---

Signal an Error Caused by an HTTP Problem

Description

The various ⁠stop_for_*()⁠ functions leverage R's condition system to signal an error with a custom type embedding the "Problem Details" structure defined in RFC 7807.

They can be used for reporting errors from HTTP APIs in a standard way.

There are also helper methods for the most common HTTP problems: HTTP 400 Bad Request, 404 Not Found, 401 Unauthorized, 403 Forbidden, 409 Conflict, and 500 Internal Server Error.

Usage

stop_for_http_problem(
  detail = NULL,
  status = 500L,
  type = NULL,
  title = NULL,
  instance = NULL,
  ...
)

stop_for_bad_request(detail = NULL, instance = NULL, ...)

stop_for_unauthorized(detail = NULL, instance = NULL, ...)

stop_for_forbidden(detail = NULL, instance = NULL, ...)

stop_for_not_found(detail = NULL, instance = NULL, ...)

stop_for_conflict(detail = NULL, instance = NULL, ...)

stop_for_internal_server_error(detail = NULL, instance = NULL, ...)

Arguments

detail	A human-readable string giving more detail about the error, if possible.
status	The HTTP status code appropriate for the response.
type	A URL pointing to human-readable documentation for this type of problem. When NULL, the type is generated based on the status code; see http_problem_types() for a list of the defaults.
title	A "short, human-readable summary of the problem type". When NULL, the title is generated based on the status code; see http_problem_types() for a list of the defaults.
instance	A URL that identifies the specific occurrence of the problem, if possible. When NULL this field is simply excluded.
...	Additional fields added to the problem as Extension Members.

Value

These functions call stop() with a custom condition (with class "http_problem_error"), so they do not return a value.

See Also

http_problem for creating the structure directly.

Examples

tryCatch(
  stop_for_bad_request("Parameter 'id' must be a number."),
  error = function(e) {
    str(e)
  }
)

---