axiosvsem-http-request
axios is a popular JavaScript library that allows you to make HTTP requests from a Node.js environment. It is a promise-based library that works in both the browser and Node.js. It is similar to the Fetch API, but with a more powerful feature set and better browser compatibility.
One of the main benefits of using axios is that it automatically transforms the response data into a JSON object, making it easy to work with.
Axios is known for user-friendly API and support for asynchronous async/await syntax making it very accessible in web scraping.
em-http-request is a Ruby gem for making asynchronous HTTP requests using EventMachine. It allows you to perform multiple requests simultaneously and handle the responses as they come in, rather than waiting for each request to complete before making the next one.
In short it supports: - Asynchronous HTTP API for single & parallel request execution - Keep-Alive and HTTP pipelining support - Auto-follow 3xx redirects with max depth - Automatic gzip & deflate decoding - Streaming response processing - Streaming file uploads - HTTP proxy and SOCKS5 support - Basic Auth & OAuth - Connection-level & global middleware support - HTTP parser via http_parser.rb - Works wherever EventMachine runs: Rubinius, JRuby, MRI
Example Use
// axios can be used with promises:
axios.get('http://httpbin.org/json')
.then(response => {
console.log(response.data);
})
.catch(error => {
console.log(error);
});
// or async await syntax:
var resp = await axios.get('http://httpbin.org/json');
console.log(resp.data);
// to make requests concurrently Promise.all function can be used:
const results = await Promise.all([
axios.get('http://httpbin.org/html'),
axios.get('http://httpbin.org/html'),
axios.get('http://httpbin.org/html'),
])
// axios also supports other type of requests like POST and even automatically serialize them:
await axios.post('http://httpbin.org/post', {'query': 'hello world'});
// or formdata
const data = {name: 'John Doe', email: 'johndoe@example.com'};
await axios.post('https://jsonplaceholder.typicode.com/users',
querystring.stringify(data),
{
headers: {
'Content-Type': 'application/x-www-form-urlencoded'
}
}
);
// default values like headers can be configured globally
axios.defaults.headers.common['User-Agent'] = 'webscraping.fyi';
// or for session instance:
const instance = axios.create({
headers: {"User-Agent": "webscraping.fyi"},
})
EventMachine.run {
http = EventMachine::HttpRequest.new('http://google.com/').get :query => {'keyname' => 'value'}
# add callback for errors:
http.errback { p 'Uh oh'; EM.stop }
# add callback for successful requests
http.callback {
p http.response_header.status
p http.response_header
p http.response
EventMachine.stop
}
}