httrvsmechanize
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.
Mechanize is a Ruby library for automating interaction with websites. It automatically stores and sends cookies, follows redirects, and can submit forms — making it behave like a web browser without needing an actual browser engine.
Key features include:
- Automatic cookie management Stores cookies received from servers and sends them back on subsequent requests, maintaining session state across multiple pages.
- Form handling Can find, fill in, and submit HTML forms programmatically. Supports text inputs, selects, checkboxes, radio buttons, and file uploads.
- Link following Navigate through pages by clicking links using their text content, CSS selectors, or href patterns.
- History and back/forward Maintains a browsing history, allowing you to go back and forward through visited pages.
- HTTP authentication Supports basic and digest HTTP authentication.
- Proxy support Can route requests through HTTP proxies.
- Redirect handling Automatically follows HTTP redirects (configurable).
Mechanize is one of the oldest and most established web interaction libraries in Ruby. It is best suited for scraping traditional server-rendered websites with forms and multi-page workflows. For JavaScript-heavy sites, a browser automation tool like Selenium or Playwright is recommended instead.
Highlights
popularproduction
Example Use
```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
```
```ruby
require 'mechanize'
agent = Mechanize.new
# Navigate to a page
page = agent.get('https://example.com')
puts page.title
# Find and click a link
page = page.link_with(text: 'Products').click
# Extract data from the page
page.search('.product').each do |product|
name = product.at('.name').text
price = product.at('.price').text
puts "#{name}: #{price}"
end
# Fill in and submit a login form
login_page = agent.get('https://example.com/login')
form = login_page.form_with(action: '/login')
form['username'] = 'user@example.com'
form['password'] = 'password123'
dashboard = agent.submit(form)
# Cookies are maintained automatically
puts dashboard.title # "Dashboard"
# Download a file
agent.get('https://example.com/report.csv').save('report.csv')
```