Curl CORS Request Python Code An example of sending a Curl request with the CORS Origin header (Cross-Origin Resource Sharing request). For CORS requests, the Origin header indicates where the request is coming from. In python, a curl is a tool for transferring data requests to and from a server using PycURL. This tool is used for testing REST APIs, downloading files, etc. This PycURL is an interface to the libcURL library in Python, and hence the PycURL is capable of inheriting all the capabilities of libcURL. Working of Python Curl. Python Code To make a GET request using cURL, call curl followed by the target URL. CURL automatically selects the HTTP GET request method unless you use the -X, -request, or -d command line option with the cURL request. In this cURL GET example, we send requests to the ReqBin echo URL. The target URL is passed as the first command-line option. The GraphQL query. For this example, I'm using the space from my Serverless SuperHero website. Python requests. Language Curl from Chrome. 1) Open the network tab in DevTools. Ctrl-click a request, 'Copy as cURL'. 3) Paste it in the curl command box.
- Curl From Python
- Python Curl Library
- Convert Curl To Python Requests
- Curl To Python Requests Definition
- Curl Works Python Requests Does Not
last modified July 6, 2020
In this tutorial, we show how to work with the Python Requests module. We grab data, postdata, stream data, and connect to secure web pages. In the examples, we use an onlineservice, an Nginx server, a Python HTTP server, and a flask application.
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The Hypertext Transfer Protocol (HTTP) is an application protocol for distributed, collaborative,hypermedia information systems. HTTP is the foundation of data communication for the World Wide Web.
Python requests
Requests is a simple and elegant Python HTTP library. It provides methods for accessing Webresources via HTTP.
We run Nginx web server on localhost. Some of our examplesuse nginx server.
Python requests version
The first program prints the version of the Requests library.
The program prints the version and copyright of Requests.
This is a sample output of the example.
Python requests reading a web page
The get() method issues a GET request; it fetches documentsidentified by the given URL.
The script grabs the content of the www.webcode.me web page.
The get() method returns a response object.
The text attribute contains the content of the response, in Unicode.
This is the output of the read_webpage.py script.
The following program gets a small web page and strips its HTML tags.
The script strips the HTML tags of the www.webcode.meweb page.
A simple regular expression is used to strip the HTML tags.
HTTP Request
An HTTP request is a message send from the client to the browser toretrieve some information or to make some action.
Request'srequest method creates a new request.Note that the request module has some higher-level methods,such as get(), post(), or put(),which save some typing for us.
The example creates a GET request and sends it to http://www.webcode.me.
Python requests getting status
The Response object contains a server's response to an HTTP request.Its status_code attribute returns HTTP status code of the response, suchas 200 or 404.
We perform two HTTP requests with the get() methodand check for the returned status.
200 is a standard response for successful HTTP requests and 404 tells that the requestedresource could not be found.
Python requests head method
The head() method retrieves document headers.The headers consist of fields, including date, server, content type,or last modification time.
The example prints the server, last modification time, and content typeof the www.webcode.me web page.
This is the output of the head_request.py program.
Python requests get method
The get() method issues a GET request to the server.The GET method requests a representation of the specified resource.
The httpbin.org is a freely available HTTP Request & Response Service.
The script sends a variable with a value to the httpbin.orgserver. The variable is specified directly in the URL.
This is the output of the example.
The get() method takes a params parameter wherewe can specify the query parameters.
The data is sent in a Python dictionary.
We send a GET request to the httpbin.org site andpass the data, which is specified in the params parameter.
We print the URL and the response content to the console.
This is the output of the example.
Python requests redirection
Redirection is a process of forwarding one URL to a different URL.The HTTP response status code 301 Moved Permanently is used for permanent URL redirection;302 Found for a temporary redirection.
In the example, we issue a GET request to the https://httpbin.org/redirect-to page.This page redirects to another page; redirect responses are stored in thehistory attribute of the response.
A GET request to https://httpbin.org/redirect-to was 302 redirected tohttps://httpbin.org.
In the second example, we do not follow a redirect.
The allow_redirects parameter specifies whether the redirectis followed; the redirects are followed by default.
This is the output of the example.
Redirect with nginx
In the next example, we show how to set up a page redirect in nginx server.
Add these lines to the nginx configuration file, which is located at/etc/nginx/sites-available/default on Debian.
After the file has been edited, we must restart nginx to apply thechanges.
This is the oldpage.html file located in the nginx document root.
This is the newpage.html.
This script accesses the old page and follows the redirect. As we already mentioned,Requests follows redirects by default.
This is the output of the example.
As we can see from the access.log file, the request was redirectedto a new file name. The communication consisted of two GET requests.
User agent
In this section, we specify the name of the user agent. We create ourown Python HTTP server.
We have a simple Python HTTP server.
If the path contains '/agent', we returnthe specified user agent.
This script creates a simple GET request to our Python HTTP server.To add HTTP headers to a request, we pass in a dictionary to theheaders parameter.
The header values are placed in a Python dictionary.
The values are passed to the headers parameter.
First, we start the server.
Then we run the script. The server responded with the name of the agent that wehave sent with the request.
Python requests post value
The post method dispatches a POST request on the givenURL, providing the key/value pairs for the fill-in form content.
The script sends a request with a name key having Peter value.The POST request is issued with the post method.
This is the output of the post_value.py script.
Python requests upload image
In the following example, we are going to upload an image. We createa web application with Flask.
This is a simple application with two endpoints. The /uploadendpoint checks if there is some image and saves it to the current directory.
We send the image to the Flask application. The file is specifiedin the files attribute of the post() method.
JSON
JSON (JavaScript Object Notation) is a lightweightdata-interchange format. It is easy for humans to read and write and formachines to parse and generate.
JSON data is a collection of key/value pairs; in Python, it is realized by a dictionary.
Read JSON
In the first example, we read JSON data from a PHP script.
The PHP script sends JSON data. It uses the json_encode()function to do the job.
The read_json.py reads JSON data sent by the PHP script.
The json() method returns the json-encodedcontent of a response, if any.
This is the output of the example.
Send JSON
Next, we send JSON data to a PHP script from a Python script.
This PHP script reads JSON data and sends back a message withthe parsed values.
This script sends JSON data to the PHP application andreads its response.
This is the data to be sent.
The dictionary containing JSON data is passed to the jsonparameter.
This is the example output.
Retrieving definitions from a dictionary
In the following example, we find definitions of a termon the www.dictionary.com.To parse HTML, we use the lxml module.
We install the lxml module withthe pip tool.
In this script, we find the definitions of the term dog on www.dictionary.com.The lxml module is used to parse the HTML code.
The lxml module can be used to parse HTML.
The textwrap module is used to wrap text to a certain width.
To perform a search, we append the term at the end of the URL.
We need to use resp.content rather than resp.textbecause html.fromstring() implicitly expects bytes as input.(The resp.content returns content in bytes whereas resp.textas Unicode text.
We parse the content. The main definitions are located inside the span tag, whichhas the one-click-content attribute.We improve the formatting by removing excessive white space and straycharacters. The text width has maximum of 50 characters. Note that such parsingis subject to change.
This is a partial list of the definitions.
Python requests streaming requests
Streaming is transmitting a continuous flow of audio and/or video datawhile earlier parts are being used. The Requests.iter_lines() iterates over the responsedata, one line at a time. Setting stream=True on the request avoids reading the contentat once into memory for large responses.
The example streams a PDF file and writes it on the disk.
Setting stream to True when making a request,Requests cannot release the connection back to the pool unless we consumeall the data or call Response.close().
We read the resource by 1 KB chunks and write them to a local file.
Python requests credentials
The auth parameter provides a basic HTTP authentication; it takesa tuple of a name and a password to be used for a realm. A security realmis a mechanism used for protecting web application resources.
Curl From Python
We use the htpasswd tool to create a user name and a passwordfor basic HTTP authentication.
Inside the nginx /etc/nginx/sites-available/default configuration file,we create a secured page. The name of the realm is 'Restricted Area'.
Inside the /usr/share/nginx/html/secure directory, we havethis HTML file.
Python Curl Library
The script connects to the secure webpage; it provides the user nameand the password necessary to access the page.
Convert Curl To Python Requests
With the right credentials, the credentials.py script returnsthe secured page.
Curl To Python Requests Definition
In this tutorial, we have worked with the Python Requests module.
Curl Works Python Requests Does Not
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