Interfaz para Desarrolladores

Esta parte de la documentación cubre todas las interfaces de Requests. En las partes donde Requests depende de librerías externas, documentamos las más importantes aquí mismo, y proveemos enlaces a la documentación canónica.

Interfaz Principal

Se puede acceder a todas las funcionalidades de Requests a través de estos 7 métodos. Todos ellos devuelven una instancia de :class: Response <Response>.

requests.request(method, url, **kwargs)

Constructs and sends a Request. Returns Response object.

Parámetros:
  • method – method for the new Request object.
  • url – URL for the new Request object.
  • params – (optional) Dictionary or bytes to be sent in the query string for the Request.
  • data – (optional) Dictionary, bytes, or file-like object to send in the body of the Request.
  • headers – (optional) Dictionary of HTTP Headers to send with the Request.
  • cookies – (optional) Dict or CookieJar object to send with the Request.
  • files – (optional) Dictionary of ‘name’: file-like-objects (or {‘name’: (‘filename’, fileobj)}) for multipart encoding upload.
  • auth – (optional) Auth tuple to enable Basic/Digest/Custom HTTP Auth.
  • timeout – (optional) Float describing the timeout of the request.
  • allow_redirects – (optional) Boolean. Set to True if POST/PUT/DELETE redirect following is allowed.
  • proxies – (optional) Dictionary mapping protocol to the URL of the proxy.
  • verify – (optional) if True, the SSL cert will be verified. A CA_BUNDLE path can also be provided.
  • stream – (optional) if False, the response content will be immediately downloaded.
  • cert – (optional) if String, path to ssl client cert file (.pem). If Tuple, (‘cert’, ‘key’) pair.

Usage:

>>> import requests
>>> req = requests.request('GET', 'http://httpbin.org/get')
<Response [200]>
requests.head(url, **kwargs)

Sends a HEAD request. Returns Response object.

Parámetros:
  • url – URL for the new Request object.
  • **kwargs – Optional arguments that request takes.
requests.get(url, **kwargs)

Sends a GET request. Returns Response object.

Parámetros:
  • url – URL for the new Request object.
  • **kwargs – Optional arguments that request takes.
requests.post(url, data=None, **kwargs)

Sends a POST request. Returns Response object.

Parámetros:
  • url – URL for the new Request object.
  • data – (optional) Dictionary, bytes, or file-like object to send in the body of the Request.
  • **kwargs – Optional arguments that request takes.
requests.put(url, data=None, **kwargs)

Sends a PUT request. Returns Response object.

Parámetros:
  • url – URL for the new Request object.
  • data – (optional) Dictionary, bytes, or file-like object to send in the body of the Request.
  • **kwargs – Optional arguments that request takes.
requests.patch(url, data=None, **kwargs)

Sends a PATCH request. Returns Response object.

Parámetros:
  • url – URL for the new Request object.
  • data – (optional) Dictionary, bytes, or file-like object to send in the body of the Request.
  • **kwargs – Optional arguments that request takes.
requests.delete(url, **kwargs)

Sends a DELETE request. Returns Response object.

Parámetros:
  • url – URL for the new Request object.
  • **kwargs – Optional arguments that request takes.

Clases de bajo nivel

class requests.Request(method=None, url=None, headers=None, files=None, data={}, params={}, auth=None, cookies=None, hooks=None)

A user-created Request object.

Used to prepare a PreparedRequest, which is sent to the server.

Parámetros:
  • method – HTTP method to use.
  • url – URL to send.
  • headers – dictionary of headers to send.
  • files – dictionary of {filename: fileobject} files to multipart upload.
  • data – the body to attach the request. If a dictionary is provided, form-encoding will take place.
  • params – dictionary of URL parameters to append to the URL.
  • auth – Auth handler or (user, pass) tuple.
  • cookies – dictionary or CookieJar of cookies to attach to this request.
  • hooks – dictionary of callback hooks, for internal usage.

Usage:

>>> import requests
>>> req = requests.Request('GET', 'http://httpbin.org/get')
>>> req.prepare()
<PreparedRequest [GET]>
deregister_hook(event, hook)

Deregister a previously registered hook. Returns True if the hook existed, False if not.

prepare()

Constructs a PreparedRequest for transmission and returns it.

register_hook(event, hook)

Properly register a hook.

class requests.Response

The Response object, which contains a server’s response to an HTTP request.

apparent_encoding

The apparent encoding, provided by the lovely Charade library (Thanks, Ian!).

content

Content of the response, in bytes.

cookies = None

A CookieJar of Cookies the server sent back.

elapsed = None

The amount of time elapsed between sending the request and the arrival of the response (as a timedelta)

encoding = None

Encoding to decode with when accessing r.text.

headers = None

Case-insensitive Dictionary of Response Headers. For example, headers['content-encoding'] will return the value of a 'Content-Encoding' response header.

history = None

A list of Response objects from the history of the Request. Any redirect responses will end up here. The list is sorted from the oldest to the most recent request.

iter_content(chunk_size=1, decode_unicode=False)

Iterates over the response data. This avoids reading the content at once into memory for large responses. The chunk size is the number of bytes it should read into memory. This is not necessarily the length of each item returned as decoding can take place.

iter_lines(chunk_size=512, decode_unicode=None)

Iterates over the response data, one line at a time. This avoids reading the content at once into memory for large responses.

json(**kwargs)

Returns the json-encoded content of a response, if any.

Parámetros:**kwargs – Optional arguments that json.loads takes.

Returns the parsed header links of the response, if any.

raise_for_status()

Raises stored HTTPError, if one occurred.

raw = None

File-like object representation of response (for advanced usage). Requires that ``stream=True` on the request.

status_code = None

Integer Code of responded HTTP Status.

text

Content of the response, in unicode.

if Response.encoding is None and chardet module is available, encoding will be guessed.

url = None

Final URL location of Response.

Request Sessions

class requests.Session

A Requests session.

Provides cookie persistience, connection-pooling, and configuration.

Basic Usage:

>>> import requests
>>> s = requests.Session()
>>> s.get('http://httpbin.org/get')
200
auth = None

Default Authentication tuple or object to attach to Request.

cert = None

SSL certificate default.

close()

Closes all adapters and as such the session

delete(url, **kwargs)

Sends a DELETE request. Returns Response object.

Parámetros:
  • url – URL for the new Request object.
  • **kwargs – Optional arguments that request takes.
get(url, **kwargs)

Sends a GET request. Returns Response object.

Parámetros:
  • url – URL for the new Request object.
  • **kwargs – Optional arguments that request takes.
get_adapter(url)

Returns the appropriate connnection adapter for the given URL.

head(url, **kwargs)

Sends a HEAD request. Returns Response object.

Parámetros:
  • url – URL for the new Request object.
  • **kwargs – Optional arguments that request takes.
headers = None

A case-insensitive dictionary of headers to be sent on each Request sent from this Session.

hooks = None

Event-handling hooks.

max_redirects = None

Maximum number of redirects to follow.

mount(prefix, adapter)

Registers a connection adapter to a prefix.

options(url, **kwargs)

Sends a OPTIONS request. Returns Response object.

Parámetros:
  • url – URL for the new Request object.
  • **kwargs – Optional arguments that request takes.
params = None

Dictionary of querystring data to attach to each Request. The dictionary values may be lists for representing multivalued query parameters.

patch(url, data=None, **kwargs)

Sends a PATCH request. Returns Response object.

Parámetros:
  • url – URL for the new Request object.
  • data – (optional) Dictionary, bytes, or file-like object to send in the body of the Request.
  • **kwargs – Optional arguments that request takes.
post(url, data=None, **kwargs)

Sends a POST request. Returns Response object.

Parámetros:
  • url – URL for the new Request object.
  • data – (optional) Dictionary, bytes, or file-like object to send in the body of the Request.
  • **kwargs – Optional arguments that request takes.
proxies = None

Dictionary mapping protocol to the URL of the proxy (e.g. {‘http’: ‘foo.bar:3128’}) to be used on each Request.

put(url, data=None, **kwargs)

Sends a PUT request. Returns Response object.

Parámetros:
  • url – URL for the new Request object.
  • data – (optional) Dictionary, bytes, or file-like object to send in the body of the Request.
  • **kwargs – Optional arguments that request takes.
resolve_redirects(resp, req, stream=False, timeout=None, verify=True, cert=None, proxies=None)

Receives a Response. Returns a generator of Responses.

send(request, **kwargs)

Send a given PreparedRequest.

stream = None

Stream response content default.

trust_env = None

Should we trust the environment?

verify = None

SSL Verification default.

Excepciones

exception requests.RequestException

There was an ambiguous exception that occurred while handling your request.

exception requests.ConnectionError

A Connection error occurred.

exception requests.HTTPError(*args, **kwargs)

An HTTP error occurred.

exception requests.URLRequired

A valid URL is required to make a request.

exception requests.TooManyRedirects

Too many redirects.

Búsqueda de Códigos de Estado

requests.codes()

Dictionary lookup object.

>>> requests.codes['temporary_redirect']
307

>>> requests.codes.teapot
418

>>> requests.codes['\o/']
200

Cookies

Codificaciones

Clases

class requests.Response

The Response object, which contains a server’s response to an HTTP request.

apparent_encoding

The apparent encoding, provided by the lovely Charade library (Thanks, Ian!).

content

Content of the response, in bytes.

cookies = None

A CookieJar of Cookies the server sent back.

elapsed = None

The amount of time elapsed between sending the request and the arrival of the response (as a timedelta)

encoding = None

Encoding to decode with when accessing r.text.

headers = None

Case-insensitive Dictionary of Response Headers. For example, headers['content-encoding'] will return the value of a 'Content-Encoding' response header.

history = None

A list of Response objects from the history of the Request. Any redirect responses will end up here. The list is sorted from the oldest to the most recent request.

iter_content(chunk_size=1, decode_unicode=False)

Iterates over the response data. This avoids reading the content at once into memory for large responses. The chunk size is the number of bytes it should read into memory. This is not necessarily the length of each item returned as decoding can take place.

iter_lines(chunk_size=512, decode_unicode=None)

Iterates over the response data, one line at a time. This avoids reading the content at once into memory for large responses.

json(**kwargs)

Returns the json-encoded content of a response, if any.

Parámetros:**kwargs – Optional arguments that json.loads takes.
links

Returns the parsed header links of the response, if any.

raise_for_status()

Raises stored HTTPError, if one occurred.

raw = None

File-like object representation of response (for advanced usage). Requires that ``stream=True` on the request.

status_code = None

Integer Code of responded HTTP Status.

text

Content of the response, in unicode.

if Response.encoding is None and chardet module is available, encoding will be guessed.

url = None

Final URL location of Response.

class requests.Request(method=None, url=None, headers=None, files=None, data={}, params={}, auth=None, cookies=None, hooks=None)

A user-created Request object.

Used to prepare a PreparedRequest, which is sent to the server.

Parámetros:
  • method – HTTP method to use.
  • url – URL to send.
  • headers – dictionary of headers to send.
  • files – dictionary of {filename: fileobject} files to multipart upload.
  • data – the body to attach the request. If a dictionary is provided, form-encoding will take place.
  • params – dictionary of URL parameters to append to the URL.
  • auth – Auth handler or (user, pass) tuple.
  • cookies – dictionary or CookieJar of cookies to attach to this request.
  • hooks – dictionary of callback hooks, for internal usage.

Usage:

>>> import requests
>>> req = requests.Request('GET', 'http://httpbin.org/get')
>>> req.prepare()
<PreparedRequest [GET]>
deregister_hook(event, hook)

Deregister a previously registered hook. Returns True if the hook existed, False if not.

prepare()

Constructs a PreparedRequest for transmission and returns it.

register_hook(event, hook)

Properly register a hook.

class requests.PreparedRequest

The fully mutable PreparedRequest object, containing the exact bytes that will be sent to the server.

Generated from either a Request object or manually.

Usage:

>>> import requests
>>> req = requests.Request('GET', 'http://httpbin.org/get')
>>> r = req.prepare()
<PreparedRequest [GET]>

>>> s = requests.Session()
>>> s.send(r)
<Response [200]>
body = None

request body to send to the server.

deregister_hook(event, hook)

Deregister a previously registered hook. Returns True if the hook existed, False if not.

headers = None

dictionary of HTTP headers.

hooks = None

dictionary of callback hooks, for internal usage.

method = None

HTTP verb to send to the server.

path_url

Build the path URL to use.

prepare_auth(auth)

Prepares the given HTTP auth data.

prepare_body(data, files)

Prepares the given HTTP body data.

prepare_cookies(cookies)

Prepares the given HTTP cookie data.

prepare_headers(headers)

Prepares the given HTTP headers.

prepare_hooks(hooks)

Prepares the given hooks.

prepare_method(method)

Prepares the given HTTP method.

prepare_url(url, params)

Prepares the given HTTP URL.

register_hook(event, hook)

Properly register a hook.

url = None

HTTP URL to send the request to.

class requests.Session

A Requests session.

Provides cookie persistience, connection-pooling, and configuration.

Basic Usage:

>>> import requests
>>> s = requests.Session()
>>> s.get('http://httpbin.org/get')
200
auth = None

Default Authentication tuple or object to attach to Request.

cert = None

SSL certificate default.

close()

Closes all adapters and as such the session

delete(url, **kwargs)

Sends a DELETE request. Returns Response object.

Parámetros:
  • url – URL for the new Request object.
  • **kwargs – Optional arguments that request takes.
get(url, **kwargs)

Sends a GET request. Returns Response object.

Parámetros:
  • url – URL for the new Request object.
  • **kwargs – Optional arguments that request takes.
get_adapter(url)

Returns the appropriate connnection adapter for the given URL.

head(url, **kwargs)

Sends a HEAD request. Returns Response object.

Parámetros:
  • url – URL for the new Request object.
  • **kwargs – Optional arguments that request takes.
headers = None

A case-insensitive dictionary of headers to be sent on each Request sent from this Session.

hooks = None

Event-handling hooks.

max_redirects = None

Maximum number of redirects to follow.

mount(prefix, adapter)

Registers a connection adapter to a prefix.

options(url, **kwargs)

Sends a OPTIONS request. Returns Response object.

Parámetros:
  • url – URL for the new Request object.
  • **kwargs – Optional arguments that request takes.
params = None

Dictionary of querystring data to attach to each Request. The dictionary values may be lists for representing multivalued query parameters.

patch(url, data=None, **kwargs)

Sends a PATCH request. Returns Response object.

Parámetros:
  • url – URL for the new Request object.
  • data – (optional) Dictionary, bytes, or file-like object to send in the body of the Request.
  • **kwargs – Optional arguments that request takes.
post(url, data=None, **kwargs)

Sends a POST request. Returns Response object.

Parámetros:
  • url – URL for the new Request object.
  • data – (optional) Dictionary, bytes, or file-like object to send in the body of the Request.
  • **kwargs – Optional arguments that request takes.
proxies = None

Dictionary mapping protocol to the URL of the proxy (e.g. {‘http’: ‘foo.bar:3128’}) to be used on each Request.

put(url, data=None, **kwargs)

Sends a PUT request. Returns Response object.

Parámetros:
  • url – URL for the new Request object.
  • data – (optional) Dictionary, bytes, or file-like object to send in the body of the Request.
  • **kwargs – Optional arguments that request takes.
resolve_redirects(resp, req, stream=False, timeout=None, verify=True, cert=None, proxies=None)

Receives a Response. Returns a generator of Responses.

send(request, **kwargs)

Send a given PreparedRequest.

stream = None

Stream response content default.

trust_env = None

Should we trust the environment?

verify = None

SSL Verification default.

Migrando a 1.x

Esta sección expone las principales diferencias entre las versiones 0.x y 1.x, y pretende facilitar las molestias a la hora de actualizar.

Cambios en el API

  • Response.json ahora es un invocable y no una propiedad de una respuesta.

    import requests
    r = requests.get('https://github.com/timeline.json')
    r.json()   # This *call* raises an exception if JSON decoding fails
    
  • El API de Session ha cambiado. Los objetos Session ya no reciben

parámetros. Session se escribe ahora con mayúscula, pero aún puede ser instanciado como session en minúscula, por razones de compatibilidad hacia atrás.

s = requests.Session()   # anteriormente session tomaba parámetros
s.auth = auth
s.headers.update(headers)
r = s.get('http://httpbin.org/headers')
  • Todos los hooks de petición han sido eliminados, con excepción de

‘response’.

  • Los ayudantes de autenticación han sido separados en módulos independientes.

Ver requests-oauthlib y requests-kerberos.

  • El parámetro para realizar peticiones de streaming ha cambiado de

prefetch a stream y la lógica ha sido invertida. Adicionalmente, stream ahora es obligatorio para leer respuestas en crudo.

# en 0.x, pasar prefetch=False haría lo mismo que
r = requests.get('https://github.com/timeline.json', stream=True)
r.raw.read(10)
  • El parámetro config en los métodos de peticiones ha sido eliminado.

Algunas de estas opciones ahora se configuran en una sesión Session, tales como keep-alive y el número máximo de redirecciones. La opción de verbosidad debe ser manipulada configurando las opciones de registro (logging).

import requests
import logging

# estas dos líneas habilitan el debugg a nivel httplib (requests->urllib3->httplib)
# verás el REQUEST, incluído HEADERS y DATA, así como RESPONSE sin HEADERS pero sin DATA.
# la única cosa que falta será el response.body, que no es registrado.
import httplib
httplib.HTTPConnection.debuglevel = 1

logging.basicConfig() # necesitas inicializar logging, de otra manera no verás nada desde requests
logging.getLogger().setLevel(logging.DEBUG)
requests_log = logging.getLogger("requests.packages.urllib3")
requests_log.setLevel(logging.DEBUG)
requests_log.propagate = True

requests.get('http://httpbin.org/headers')

Licenciamiento

Una diferencia clave que no tiene nada que ver con el API es el cambio en la licencia, de ISC a Apache 2.0. La licencia Apache 2.0 asegura que las contribuciones a Requests también estén cubiertas por la licencia Apache 2.

Migrando a 2.x

Comparado con el release 1.0, hay relativamente pocos cambios compatibles con versiones anteriores, pero aún hay algunos pocos temas de los cuales estar pendientes en esta liberación.

Para más detalles en los cambios de este release, incluidos nuevas API, enlaces relevantes a los issues en GitHub y algunas de las correcciones de bug, lee el blog de Cory al respecto

Cambios en la API

  • Hay un par de cambios en cómo Requests maneja las excepciones.

RequestException es ahora una subclase de IOError en vez de RuntimeError debido a que categoriza con mayor precisión este tipo de error. Además, una secuencia de escape URL inválida ahora arroja una subclase de RequestException en vez de ValueError.

requests.get('http://%zz/')   # arroja un requests.exceptions.InvalidURL

Por último, las excepciones httplib.IncompleteRead causadas por una incorrecta codificación por trozos (chunked) ahora arrojará un ChunkedEncodingError.

  • La API de proxy ha cambiado ligeramente: ahora se requiere el esquema

para la URL del proxy.

proxies = {
  "http": "10.10.1.10:3128",    # ahora usa http://10.10.1.10:3128
}

# En Requests 1.x, esto era legal, en Requests 2.x,
#  esto arroja requests.exceptions.MissingSchema
requests.get("http://example.org", proxies=proxies)

Cambios en el Comportamiento

  • Las llaves en el diccionario headers ahora son cadenas nativas strings

para todas las versiones de Python , por ejemplo, bytestring en Python 2 y unicode on Python 3. Si las llaves no son cadenas nativas (unicode en Python2 o bytestring en Python 3) serán convertidas al tipo de cadena nativa asumiendo codificación UTF-8.

  • Los Timeouts se comportan ligeramente diferente. En peticiones de streaming, sólo aplicann al intento de conexión. En peticiones regulares, el timeout es aplicado al proceso de conexión y a la descarga completa.

    tarball_url = 'https://github.com/kennethreitz/requests/tarball/master'
    
    # Un segundo de timeout para el intento de conexión
    # Tiempo ilimitado para descargar el tarball
    r = requests.get(tarball_url, stream=True, timeout=1)
    
    # Un segungo de para el intento de conexión
    # Otro segundo completo para descargar el tarball
    r = requests.get(tarball_url, timeout=1)