Consuming HTTP Services in Python Transcripts
Chapter: Calling SOAP services from Python
Lecture: Introduction to developing with SOAP services
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0:03
So we are in a new place in this course,
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now we've made our way over to the data format section,
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and we are going to be talking about soap clients.
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We are going to see how to consume Soap services from Python,
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and the answer is actually not to bad there, there are some pretty cool projects
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that we are going to be using.
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So I talked at the beginning of this course a little bit about the network,
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the spectrum of network services, and we put Soap in there,
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in the really nice to work with if you have the tooling in some ways
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but also kind of old school and very burningsome if you don't.
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So, I just want to reiterate that, if you get a choice
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between making an http restful service and a Soap service,
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choose the rest service, if you got to consume one,
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choose the rest service but we are going to talk about Soap
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because there are many internal Soap services,
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if you work in large companies, there are probably Soap services all over the place,
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and what you'll learn here is how you can work with the existing code,
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okay, this is not an advocation of Soap,
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this is just a- we live in a world where there used to be many Soap services,
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and you may still run across them so how do we work with them,
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alright, and just to remind you how this went, recall we had this function,
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doubleAnInteger which we were calling on a Soap service,
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and what happens is we come in, we call this function,
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it generates a Soap envelope and the Soap envelope contains things like
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it's going to run, what the values are, and it's very name space laden
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to describe all of its types, so we are going to get a message like this,
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and all of this is really to send two pieces of information,
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we want to call the thing, doubleAnInteger, and we want to pass the number 1, 2, 3,
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the server is going to do the work, it will pull this all apart,
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it will run that operation and it's going to, not surprisingly double that number
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and send the message back that looks similar, like this.
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And here you can see the response came back and the response is 2,4,6.
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Okay, so this is the Soap world, and what are the properties
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benefits and drawbacks really of Soap services, all data is exchanged via http post,
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now on one hand, you might not really care,
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like you might not be really into exactly matching the architecture of the internet and the web,
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and that's fine, but one of the challenges you have with everything
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being tunneled if you will over http post is that nothing is cashable out,
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outside of maybe the server in memory cashing in,
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but the verb post is not cashable and this causes many problems
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on the public internet.
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Next, all the operations target single url, so they might go against server/service
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and then the action header tells you which operation on that service to run,
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so it's not again, just kind of not really working the way the internet works,
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because we're using post, nothing is cashable, xml format
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especially with all those name spaces is really ---
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and we don't want to use it, right, we've seen json as better from a bandwidth perspective,
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better from a human readability perspective and it's just simpler
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for most clients especially Python because dictionaries and json match
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so closely to each other.
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However, with tooling support, Soap does lead to pretty quick development.
