Consuming HTTP Services in Python Transcripts
Chapter: Calling SOAP services from Python
Lecture: Concept: Using suds
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0:01
So let's look at how we work with Soap services from suds in Python.
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It all begins with the wsdl, as we've seen and then we can use the wsdl
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plus the suds package to generate a suds proxy or suds client.
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Now, this suds proxy knows all he structure and schema and operations
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that the Soap web service wants to call, that the Soap web service provides.
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So once we have the proxy, it knows how to do the Soap exchange
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basically seamlessly to us and afterwards, we just work with this local class
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that is created at runtime with suds and everything looks pretty easy, in code,
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we just import the client from suds.client, we have our url to the wsdl,
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and we just allocate an instance of the client class
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and provided the wsdl, boom, we're done.
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Now it's parsed and understood that web service description language
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it gives us this client which has a service property, and on there,
0:58
we can call functions which will map dynamically to the operations on the server.
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Now, you may want to know exactly what this client thinks the operations are,
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so we've seen that we can just print it out and we get a really nice listing
1:13
of what the operations and rich types are, so if we print this,
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we get something like this, service blog and it's going to have a couple of ports,
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these are actually the various soap 1 and soap 1.2 formats
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that it supports but typically they are identical,
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and here our example had 5 methods and 2 rich types,
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that array of posts I'd really like to see that just come back as a list
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but hey, it's not that big of a deal, alright, so we have our all post,
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create post, delete post, and these are normally verbs,
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not nouns like we have in the http restful services,
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where the verbs are actually the actions we take on the nouns,
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here these are things like delete post
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or create post or get me the post, stuff like that.
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Once you know what the operations are and the signatures of them,
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you are going to want to call those functions, right,
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so we are going to make sure we've already got the client,
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we've got the client created from the wsdl,
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and then we just say client.service and we start calling these operations,
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any time you see an array of thing, you know,
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the arrays actually contained in the first element of that tuple that comes back there,
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and then these come back already parsed into post objects,
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so we can say post.Title and post.ViewCount.
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We can also call functions that take parameters so client.service.UpdatePost
2:29
it takes a post id, title, content and a view count.
