sanic/docs/sanic/request_data.md
2019-06-11 11:09:29 +09:00

8.2 KiB

Request Data

When an endpoint receives a HTTP request, the route function is passed a Request object.

The following variables are accessible as properties on Request objects:

  • json (any) - JSON body

    from sanic.response import json
    
    @app.route("/json")
    def post_json(request):
        return json({ "received": True, "message": request.json })
    
  • args (dict) - Query string variables. A query string is the section of a URL that resembles ?key1=value1&key2=value2. If that URL were to be parsed, the args dictionary would look like {'key1': ['value1'], 'key2': ['value2']}. The request's query_string variable holds the unparsed string value. Property is providing the default parsing strategy. If you would like to change it look to the section below (Changing the default parsing rules of the queryset).

    from sanic.response import json
    
    @app.route("/query_string")
    def query_string(request):
        return json({ "parsed": True, "args": request.args, "url": request.url, "query_string": request.query_string })
    
  • query_args (list) - On many cases you would need to access the url arguments in a less packed form. query_args is the list of (key, value) tuples. Property is providing the default parsing strategy. If you would like to change it look to the section below (Changing the default parsing rules of the queryset). For the same previous URL queryset ?key1=value1&key2=value2, the query_args list would look like [('key1', 'value1'), ('key2', 'value2')]. And in case of the multiple params with the same key like ?key1=value1&key2=value2&key1=value3 the query_args list would look like [('key1', 'value1'), ('key2', 'value2'), ('key1', 'value3')].

    The difference between Request.args and Request.query_args for the queryset ?key1=value1&key2=value2&key1=value3

    from sanic import Sanic
    from sanic.response import json
    
    app = Sanic(__name__)
    
    
    @app.route("/test_request_args")
    async def test_request_args(request):
        return json({
            "parsed": True,
            "url": request.url,
            "query_string": request.query_string,
            "args": request.args,
            "raw_args": request.raw_args,
            "query_args": request.query_args,
        })
    
    if __name__ == '__main__':
        app.run(host="0.0.0.0", port=8000)
    

    Output

    {
      "parsed":true,
      "url":"http:\/\/0.0.0.0:8000\/test_request_args?key1=value1&key2=value2&key1=value3",
      "query_string":"key1=value1&key2=value2&key1=value3",
      "args":{"key1":["value1","value3"],"key2":["value2"]},
      "raw_args":{"key1":"value1","key2":"value2"},
      "query_args":[["key1","value1"],["key2","value2"],["key1","value3"]]
    }
    

    raw_args contains only the first entry of key1. Will be deprecated in the future versions.

  • files (dictionary of File objects) - List of files that have a name, body, and type

    from sanic.response import json
    
    @app.route("/files")
    def post_json(request):
        test_file = request.files.get('test')
    
        file_parameters = {
            'body': test_file.body,
            'name': test_file.name,
            'type': test_file.type,
        }
    
        return json({ "received": True, "file_names": request.files.keys(), "test_file_parameters": file_parameters })
    
  • form (dict) - Posted form variables.

    from sanic.response import json
    
    @app.route("/form")
    def post_json(request):
        return json({ "received": True, "form_data": request.form, "test": request.form.get('test') })
    
  • body (bytes) - Posted raw body. This property allows retrieval of the request's raw data, regardless of content type.

    from sanic.response import text
    
    @app.route("/users", methods=["POST",])
    def create_user(request):
        return text("You are trying to create a user with the following POST: %s" % request.body)
    
  • headers (dict) - A case-insensitive dictionary that contains the request headers.

  • method (str) - HTTP method of the request (ie GET, POST).

  • ip (str) - IP address of the requester.

  • port (str) - Port address of the requester.

  • socket (tuple) - (IP, port) of the requester.

  • app - a reference to the Sanic application object that is handling this request. This is useful when inside blueprints or other handlers in modules that do not have access to the global app object.

    from sanic.response import json
    from sanic import Blueprint
    
    bp = Blueprint('my_blueprint')
    
    @bp.route('/')
    async def bp_root(request):
        if request.app.config['DEBUG']:
            return json({'status': 'debug'})
        else:
            return json({'status': 'production'})
    
    
  • url: The full URL of the request, ie: http://localhost:8000/posts/1/?foo=bar

  • scheme: The URL scheme associated with the request: http or https

  • host: The host associated with the request: localhost:8080

  • path: The path of the request: /posts/1/

  • query_string: The query string of the request: foo=bar or a blank string ''

  • uri_template: Template for matching route handler: /posts/<id>/

  • token: The value of Authorization header: Basic YWRtaW46YWRtaW4=

Changing the default parsing rules of the queryset

The default parameters that are using internally in args and query_args properties to parse queryset:

  • keep_blank_values (bool): False - flag indicating whether blank values in percent-encoded queries should be treated as blank strings. A true value indicates that blanks should be retained as blank strings. The default false value indicates that blank values are to be ignored and treated as if they were not included.
  • strict_parsing (bool): False - flag indicating what to do with parsing errors. If false (the default), errors are silently ignored. If true, errors raise a ValueError exception.
  • encoding and errors (str): 'utf-8' and 'replace' - specify how to decode percent-encoded sequences into Unicode characters, as accepted by the bytes.decode() method.

If you would like to change that default parameters you could call get_args and get_query_args methods with the new values.

For the queryset /?test1=value1&test2=&test3=value3:

from sanic.response import json

@app.route("/query_string")
def query_string(request):
    args_with_blank_values = request.get_args(keep_blank_values=True)
    return json({
        "parsed": True,
        "url": request.url,
        "args_with_blank_values": args_with_blank_values,
        "query_string": request.query_string
    })

The output will be:

{
    "parsed": true,
    "url": "http:\/\/0.0.0.0:8000\/query_string?test1=value1&test2=&test3=value3",
    "args_with_blank_values": {"test1": ["value1"], "test2": "", "test3": ["value3"]},
    "query_string": "test1=value1&test2=&test3=value3"
}

Accessing values using get and getlist

The request properties which return a dictionary actually return a subclass of dict called RequestParameters. The key difference when using this object is the distinction between the get and getlist methods.

  • get(key, default=None) operates as normal, except that when the value of the given key is a list, only the first item is returned.
  • getlist(key, default=None) operates as normal, returning the entire list.
from sanic.request import RequestParameters

args = RequestParameters()
args['titles'] = ['Post 1', 'Post 2']

args.get('titles') # => 'Post 1'

args.getlist('titles') # => ['Post 1', 'Post 2']

Accessing the handler name with the request.endpoint attribute

The request.endpoint attribute holds the handler's name. For instance, the below route will return "hello".

from sanic.response import text
from sanic import Sanic

app = Sanic()

@app.get("/")
def hello(request):
    return text(request.endpoint)

Or, with a blueprint it will be include both, separated by a period. For example, the below route would return foo.bar:

from sanic import Sanic
from sanic import Blueprint
from sanic.response import text


app = Sanic(__name__)
blueprint = Blueprint('foo')

@blueprint.get('/')
async def bar(request):
    return text(request.endpoint)

app.blueprint(blueprint)

app.run(host="0.0.0.0", port=8000, debug=True)