Requests API
Allow to send HTTP/1.1 requests.
No need to manually add query strings to your URLs, or to form-encode POST data.
Basic usage :
import requests ... response = requests.get('https://api.github.com/events') |
Session Object
A Session object has all the methods of the main Requests API.
Feature :
– persist some parameters across requests.
– persist cookies across all requests made from the Session instance
– use urllib3’s connection pooling (may improve performance).
Usage
# create a session
session = requests.Session()
# set some persistent parameters
# ex: set the certificate path
session.verify = '/etc/foo/ca.crt'
# ex: set auth
session.auth = HTTPBasicAuth('username', 'password')
# execute some requests
# a first one
resp = session.post('https://foo.bar/do')
# a seconde one
resp = session.get('https://foo.bar/get') |
Send a JSON request
…
Processing a JSON response
The json() function : convert the response to a « json thing »
Just invoke json() on the response object:
resp = requests.get('http://foo.com/data') jsonResult = resp.json() |
Process a simple object returned as json
JSON simple objects (that is not an array) are converted into a dictionary.
Example with a json response as :
{'node': 'es02', 'disk.indices': '7.8gb', 'disk.percent': '84'} |
We process it as any dictionary:
line = resp.json() print('node=', line['node']) print('disk.indices=', line['disk.indices']) print('disk.percent=', line['disk.percent']) |
Output :
node= es02 disk.indices= 7.9gb disk.percent= 82 |
Process a array object returned as json
JSON array objects are converted into a list.
Element of the list (recursively) that are themselves array objects are again converted into a list.
Basic objects are converted to dictionary (as above).
Example with a json response as :
[<br /> {"node":"es03","disk.indices":"10.9gb","disk.percent":"82"},<br /> {"node":"es02","disk.indices":"7.9gb","disk.percent":"82"},<br /> {"node":"es01","disk.indices":"3.3gb","disk.percent":"82"}<br />] |
We process it as list at first level and dictionary at second level :
lines = resp.json() for line in lines: print('new element found') print('node=', line['node']) print('disk.indices=', line['disk.indices']) print('disk.percent=', line['disk.percent']) |
Output :
new element found node= es01 disk.indices= 3.3gb disk.percent= 82 new element found node= es02 disk.indices= 7.9gb disk.percent= 82 new element found node= es03 disk.indices= 10.9gb disk.percent= 82 Process finished with exit code 0 |
Common errors
Problem : protocol scheme is missing in the url.
Symptom : requests.get()/post()/... raise a InvalidSchema exception such as
requests.exceptions.InvalidSchema: No connection adapters were found for 'localhost:8000/foo'
Solution :
Prefix the url by the protocol : http, https…