Sending and Receiving XML using http post - ruby-on-rails

Question

I am new to rails and looking someone to point me in the right direction in how to accomplish the following:-
I need to communicate with an external api by either passing an XML document directly
into the cgi (https://api.domain.com/v1/method.cgi) and set the content-type to
"text/xml", or pass it as a parameter and set the content-type to "text/plain"
I supposedly get an XML response back instead of the HTML response, so no need to
download the HTML response, store it, then render a local copy for the user; nor will
i need to stick the XML document within a parameter of a locally generated HTML form
to submit it via the browser to avoid downloading the HTML.
Each API method has example xml code for (Sending, The Response, DTD, Schema)
What is the best tools/techniques to accomplish this !??
One of their simpler methods is as follows :-
**SEND**
<?xml version="1.0" encoding="utf-8" ?>
<SoftwareAPI>
<Method>ListUsers</Method>
<APIKey>123</APIKey>
<Account>
<UserName>admin</UserName>
<Password>Password</Password>
</Account>
</SoftwareAPI>
**RESPONSE**
<?xml version="1.0" encoding="utf-8" ?>
<SoftwareAPIResponse>
<TimeNow>2012-01-23T16:44:00Z</TimeNow>
<ResponseId>01-23-1232729040-23456</ResponseId>
<ListUsersResponse>
<User>
<Team>team</Team>
<Office>office</Office>
<UserName>Joe.Bloggs</UserName>
<Password>Password123</Password>
<FullName>Joe Bloggs</FullName>
<Language>Auto-Detect</Language>
<Telephone>[phone]</Telephone>
<ResponseEmail>joebloggs#domain.co.uk</ResponseEmail>
</User>
</ListUsersResponse>
</SoftwareAPIResponse>
This API method needs no interaction from the user or view, should the coding be done
from the controller or should I create a model for all the api methods ?
How do I perform a post to the cgi url with the specified XML above and process the
response XML and display in a view ?
What are the best practices for accomplishing this ?
Many Thanks in Advance
Jonny

Answer 1

You guessed it: the best place for your API client is a model. Using a library such as HTTParty or RestClient, this task is fairly easy. The controller should do no more than request the data needed for the view.
Here's some sample code using HTTParty. Since I don't have the details, you'll have to modify it a bit. This would be a model:
class JonnyService
include HTTParty
base_uri 'http://localhost:3000'
end
Then you can use it like this. Note that it might be better to move some of this logic (e.g. creation of the post params for each service method) into the model as class methods for additional convenience.
options = {
:body => {
:SoftwareAPI => {
:Method => 'ListUsers',
:APIKey => '123',
:Account => {
:UserName => 'admin',
:Password => 'password'
}
}
}
}
response = JonnyService.post('/service.xml', options)
puts response.inspect
#response can be treated as a data structure:
puts response['ResponseId']