(Ruby) REST Follow Redirects

Demonstrates how to follow a 302/303 redirect response.

Chilkat Ruby Downloads install from rubygems.org gem install chilkat or download... Ruby Library for Windows, MacOS, Linux, Alpine Linux

require 'chilkat'

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

rest = Chilkat::CkRest.new()

bTls = true
port = 443
bAutoReconnect = true
success = rest.Connect("chilkatsoft.com",port,bTls,bAutoReconnect)
if (success != true)
    print rest.lastErrorText() + "\n";
    exit
end

# Send a POST to a URL that will respond with a 302 redirect..
rest.AddQueryParam("firstName","John")
rest.AddQueryParam("lastName","Doe")
responseText = rest.fullRequestFormUrlEncoded("POST","/echoPost302.asp")
if (rest.get_LastMethodSuccess() != true)
    print rest.lastErrorText() + "\n";
    exit
end

statusCode = rest.get_ResponseStatusCode()

# Examine the response status code
if (statusCode < 300)
    print "Not a redirect." + "\n";
    print responseText + "\n";
    exit
end

if (statusCode > 399)
    print "Error response: Status code = " + statusCode.to_s() + "\n";
    print responseText + "\n";
    exit
end

print "Redirect status code = " + statusCode.to_s() + "\n";

# The response header will contain a Location field with the redirect URL, such as this:
# Location: http://www.chilkatsoft.com/echoPostFinal.asp

# The response status code determines how the client should behave.
# Here are some common possibilities:

# 301: Moved Permanently
# This and all future requests should be directed to the given URI.  (Keep the original HTTP method for the redirect.  In this case, the 
# original request was a POST, so we POST to the redirect URL.)

# 302: Found (aka Object Moved aka Moved Temporarily)
# This is the most popular redirect code, but also an example of industrial practice contradicting the standard. HTTP/1.0 specification (RFC 1945 ) required the client
# to perform a temporary redirect (the original describing phrase was Moved Temporarily), but popular browsers implemented it as a 303 See Other. Therefore, HTTP/1.1
# added status codes 303 and 307 to disambiguate between the two behaviors. However, the majority of Web applications and frameworks still use the 302 status code
# as if it were the 303.

# 303: See Other
# The response to the request can be found under another URI using a GET method. When received in response to a PUT, it should be assumed that the server has
# received the data and the redirect should be issued with a separate GET message.

# 307: Temporary Redirect
# In this occasion, the request should be repeated with another URI, but future requests can still use the original URI. In contrast to 303, the request method
# should not be changed when reissuing the original request. For instance, a POST request must be repeated using another POST request.

print rest.responseHeader() + "\n";

# redirectUrl is a CkUrl
redirectUrl = rest.RedirectUrl()
if (rest.get_LastMethodSuccess() == false)
    print "No Location header found for redirect." + "\n";
    exit
end

# Prep for the redirect..
rest.ClearAllParts()

# Disconnect and re-connect.  
# (This can be skipped if both the host and SSL/TLS conditions are the same.)
rest.Disconnect(100)
success = rest.Connect(redirectUrl.host(),redirectUrl.get_Port(),redirectUrl.get_Ssl(),bAutoReconnect)
if (success != true)
    print rest.lastErrorText() + "\n";
    exit
end

if ((statusCode == 301) or (statusCode == 307))
    # Redirect using a POST, sending the same params to the new destination
    rest.AddQueryParam("firstName","John")
    rest.AddQueryParam("lastName","Doe")
    responseText = rest.fullRequestFormUrlEncoded("POST",redirectUrl.path())
    if (rest.get_LastMethodSuccess() != true)
        print rest.lastErrorText() + "\n";
        exit
    end

end

if ((statusCode == 302) or (statusCode == 303))
    # Redirect using a GET, sending the query params found in the redirect URL.
    responseText = rest.fullRequestFormUrlEncoded("GET",redirectUrl.pathWithQueryParams())
    if (rest.get_LastMethodSuccess() != true)
        print rest.lastErrorText() + "\n";
        exit
    end

end

# Show the final status code and the response text.
print "Final status code = " + rest.get_ResponseStatusCode().to_s() + "\n";

print "Final response text (HTML, XML, JSON, or whatever..)" + "\n";
print responseText + "\n";