axiosvshttr
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.
The aim of httr is to provide a wrapper for the curl package, customised to the demands of modern web APIs.
Key features:
- Functions for the most important http verbs: GET(), HEAD(), PATCH(), PUT(), DELETE() and POST().
- Automatic connection sharing across requests to the same website (by default, curl handles are managed automatically), cookies are maintained across requests, and a up-to-date root-level SSL certificate store is used.
- Requests return a standard reponse object that captures the http status line, headers and body, along with other useful information.
- Response content is available with content() as a raw vector (as = "raw"), a character vector (as = "text"), or parsed into an R object (as = "parsed"), currently for html, xml, json, png and jpeg.
- You can convert http errors into R errors with stop_for_status().
- Config functions make it easier to modify the request in common ways: set_cookies(), add_headers(), authenticate(), use_proxy(), verbose(), timeout(), content_type(), accept(), progress().
- Support for OAuth 1.0 and 2.0 with oauth1.0_token() and oauth2.0_token(). The demo directory has eight OAuth demos: four for 1.0 (twitter, vimeo, withings and yahoo) and four for 2.0 (facebook, github, google, linkedin). OAuth credentials are automatically cached within a project.
Example Use
```javascript
// 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"},
})
```
```r
library(httr)
# GET requests:
resp <- GET("http://httpbin.org/get")
status_code(resp) # status code
headers(resp) # headers
str(content(resp)) # body
# POST requests:
# Form encoded
resp <- POST(url, body = body, encode = "form")
# Multipart encoded
resp <- POST(url, body = body, encode = "multipart")
# JSON encoded
resp <- POST(url, body = body, encode = "json")
# setting cookies:
resp <- GET("http://httpbin.org/cookies", set_cookies("MeWant" = "cookies"))
content(r)$cookies # get response cookies
```