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
. ReturnsResponse
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]>
- method – method for the new
-
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.
- url – URL for the new
-
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.
- url – URL for the new
-
requests.
patch
(url, data=None, **kwargs)¶ Sends a PATCH request. Returns
Response
object.Parámetros:
-
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.
- url – URL for the new
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.
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.
-
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
-
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.
- url – URL for the new
-
get
(url, **kwargs)¶ Sends a GET request. Returns
Response
object.Parámetros: - url – URL for the new
Request
object. - **kwargs – Optional arguments that
request
takes.
- url – URL for the new
-
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.
- url – URL for the new
-
headers
= None¶ A case-insensitive dictionary of headers to be sent on each
Request
sent from thisSession
.
-
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.
- url – URL for the new
-
params
= None¶ Dictionary of querystring data to attach to each
Request
. The dictionary values may be lists for representing multivalued query parameters.
-
proxies
= None¶ Dictionary mapping protocol to the URL of the proxy (e.g. {‘http’: ‘foo.bar:3128’}) to be used on each
Request
.
-
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.
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.
- url – URL for the new
-
get
(url, **kwargs) Sends a GET request. Returns
Response
object.Parámetros: - url – URL for the new
Request
object. - **kwargs – Optional arguments that
request
takes.
- url – URL for the new
-
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.
- url – URL for the new
-
headers
= None A case-insensitive dictionary of headers to be sent on each
Request
sent from thisSession
.
-
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.
- url – URL for the new
-
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:
-
post
(url, data=None, **kwargs) Sends a POST request. Returns
Response
object.Parámetros:
-
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:
-
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 objetosSession
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.InvalidURLPor último, las excepciones
httplib.IncompleteRead
causadas por una incorrecta codificación por trozos (chunked) ahora arrojará unChunkedEncodingError
.
- 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)