How do I submit this HTTPs form with Ruby?

Question

LinkedIn's API lets a user submit their email and password into a form that looks like the following:

https://www.linkedin.com/uas/oauth2/authorization?client_id=nhrepd2sjd6k&raise_errors=true&redirect_uri=https%3A%2F%2Fwww.treatings.co%2Fv1%2Ftoken_exchanges&response_type=code&scope=r_fullprofile+r_emailaddress&state=JV4qrQfA8p%2BAKtyq1DFgaaXeRZSg50lQrAU%2Fc%2BBSXaU%3D

With the correct credentials, LinkedIn redirects to the redirect URI in the above URL with code and state parameters:

https://www.treatings.co/v1/token_exchanges?code=CODE&state=STATE

I have two questions:

1. How can I use Ruby to submit the form's URL with an email and password?
2. Once I get a response, how do I obtain the URL in the second?

Thanks!

Answer 1

Ruby comes with Net::HTTP and OpenURI. Of the two, OpenURI is the easier to use.

Other gems exist to do the same things, but to start I'd recommend sticking with OpenURI until you find specific reasons to look elsewhere.

OpenURI's documentation has plenty of examples to get you started, but the basic command is:

open('http://www.example.com/index.html').read

which would return the contents of the page as a string. You can replace the URL above with your URL containing the form contents, which will cause the server to respond with whatever it would normally return.

Because you're using a HTTPS URL, OpenURI will sense that and use a SSL connection automatically. That is also covered in the documentation.

Redirection will be handled automatically by OpenURI, and you can ask it what its landing URL was. At that point you can use Ruby's URI class to parse the URL, extract the query using query, then cleanly retrieve the values using decode_www_form.

There are plenty of examples here and around the internet to point you in the right direction.

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I'm not sure that OpenURI supports POST....

Then there are plenty of gems that do support it, or drop down a level and use Net::HTTP. A search for "ruby http clients" reveals much.