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Now, we have a Response object called r. We can get all the information we need from this object. What about the other HTTP request types: These are all just as simple:. You often want to send some sort of data in the URL's query string.
Requests allows you to provide these arguments as a dictionary of strings, using the params keyword argument. Note that any dictionary key whose value is None will not be added to the URL's query string. Requests will automatically decode content from the server. Most unicode charsets are seamlessly decoded. When you make a request, Requests makes educated guesses about the encoding of the response based on the HTTP headers.
The text encoding guessed by Requests is used when you access r. You can find out what encoding Requests is using, and change it, using the r. If you change the encoding, Requests will use the new value of r. You might want to do this in any situation where you can apply special logic to work out what the encoding of the content will be. In situations like this, you should use r. This will let you use r. Requests will also use custom encodings in the event that you need them.
If you have created your own encoding and registered it with the codecs module, you can simply use the codec name as the value of r. The gzip and deflate transfer-encodings are automatically decoded for you. For example, to create an image from binary data returned by a request, you can use the following code:.
In case the JSON decoding fails, r. No JSON object could be decoded. It should be noted that the success of the call to r. Some servers may return a JSON object in a failed response e. Such JSON will be decoded and returned. To check that a request is successful, use r. In the rare case that you'd like to get the raw socket response from the server, you can access r.
Once you do, you can do this:. In general, however, you should use a pattern like this to save what is being streamed to a file:. When streaming a download, the above is the preferred and recommended way to retrieve the content. An important note about using Response. If you really need access to the bytes as they were returned, use Response. If you'd like to add HTTP headers to a request, simply pass in a dict to the headers parameter. Custom headers are given less precedence than more specific sources of information.
Furthermore, Requests does not change its behavior at all based on which custom headers are specified. The headers are simply passed on into the final request. All header values must be a string , bytestring, or unicode. While permitted, it's advised to avoid passing unicode header values. Typically, you want to send some form-encoded data — much like an HTML form. To do this, simply pass a dictionary to the data argument. Your dictionary of data will automatically be form-encoded when the request is made:.
You can also pass a list of tuples to the data argument. This is particularly useful when the form has multiple elements that use the same key:. There are times that you may want to send data that is not form-encoded. If you pass in a string instead of a dict , that data will be posted directly. Instead of encoding the dict yourself, you can also pass it directly using the json parameter added in version 2. Note, the json parameter is ignored if either data or files is passed.
By default, requests does not support this, but there is a separate package which does - requests-toolbelt. You should read the toolbelt's documentation for more details about how to use it. For sending multiple files in one request refer to the advanced section. It is strongly recommended that you open files in binary mode. This is because Requests may attempt to provide the Content-Length header for you, and if it does this value will be set to the number of bytes in the file.
Errors may occur if you open the file in text mode. If we made a bad request a 4XX client error or 5XX server error response , we can raise it with Response. The dictionary is special, though: It is also special in that the server could have sent the same header multiple times with different values, but requests combines them so they can be represented in the dictionary within a single mapping, as per RFC To send your own cookies to the server, you can use the cookies parameter:.
Cookies are returned in a RequestsCookieJar , which acts like a dict but also offers a more complete interface, suitable for use over multiple domains or paths. Cookie jars can also be passed in to requests:. We can use the history property of the Response object to track redirection. The list is sorted from the oldest to the most recent response. You can tell Requests to stop waiting for a response after a given number of seconds with the timeout parameter. Nearly all production code should use this parameter in nearly all requests.
Failure to do so can cause your program to hang indefinitely:. If no timeout is specified explicitly, requests do not time out. In the event of a network problem e. If a request times out, a Timeout exception is raised.
If a request exceeds the configured number of maximum redirections, a TooManyRedirects exception is raised. All exceptions that Requests explicitly raises inherit from requests.
Check out the advanced section. You are currently looking at the documentation of the development release. Sponsored by Linode and other wonderful organizations. This page gives a good introduction in how to get started with Requests.
First, make sure that: Requests is installed Requests is up-to-date Let's get started with some simple examples. Begin by importing the Requests module: Consider the GitHub timeline again: Once you do, you can do this: Note An important note about using Response. For example, we didn't specify our user-agent in the previous example: Your dictionary of data will automatically be form-encoded when the request is made: Warning It is strongly recommended that you open files in binary mode.
A recipient MAY combine multiple header fields with the same field name into one "field-name: Failure to do so can cause your program to hang indefinitely: Note timeout is not a time limit on the entire response download; rather, an exception is raised if the server has not issued a response for timeout seconds more precisely, if no bytes have been received on the underlying socket for timeout seconds.
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