Building Data-Driven Web Apps with Pyramid and SQLAlchemy Transcripts
Chapter: User input and HTML forms
Lecture: Concept: One source of data
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Let's review this concept
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of having just one source of data
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rather than four or five being passed in
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from these different sources on request.
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So we saw that if we just create just a few lines of code
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the simple create function that takes your request
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and returns this thing we created
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called a request dictionary
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which is really a fancy dictionary
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that lets you do sort of arbitrary dynamic access
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into its keys as if they were fields or attributes
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rather than dictionary style with .get
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or square brackets and things like that.
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Then what we're going to do is we're going to
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pass in the request and we're going to say
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"Let's go and get the query string
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and the headers and the Post and the matchdict
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and all of that stuff and merge it
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into one super dictionary."
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And if there's data that is in both
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like say in the matchdict and the Get
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the last one wins.
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So in this case anything in matchdict
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is going to override anything in the query string.
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And then if we just use this in our action methods
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it gets so much simpler.
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So over here in our registered post
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we say create us one of these dictionaries
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when we say d.email_address d.password
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where email_address and password
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these were the named input elements in our form.
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This is certainly an optional design pattern
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but it's very very useful to help just centralize
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where all this data is coming from.
