Building data-driven web apps with Flask and SQLAlchemy Transcripts
Chapter: Introducing the Flask framework
Lecture: Building block: Models
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Here's another view method.
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It's going to return the popular packages.
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This is going to be the most popular packages on PyPI
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and we're going to have the name and the summary for each one
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and the URL for each one, and we'll have a list of those.
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And our template, popular.html, is going to need that list
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with all those details to generate dynamically some kind
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of unordered list or whatever it is.
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So what we're going to do is
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we're going to come up with this data.
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Here, we're just kind of hacking it in.
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But in reality, popular would probably be a query
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from the database with an order by
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number of downloads this month
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or something kind of complicated like that.
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So we'll somehow, usually database or other API
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we're going to get the most popular packages
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and we need to provide that to the template.
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So here, we say render template, give the template name
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and then we have keyword arguments
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packages and then our list here.
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So in the template, it's going to be a variable
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to find packages, and it's going to have this value here.
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And we can pass as many of these as we want
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or could even have a dictionary unpack it
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or like I said at the beginning of this chapter
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there's actually some cool patterns
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where we would just return a dictionary itself.
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So this is the model that flows
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from the view methods over to the template.
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So here, we're going to pass these by keyword arguments
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and we can also pass methods or functions.
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That's pretty cool, because sometimes you want
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to have a little helper function that convert this
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to an integer or give me a default value
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or get the name of this, unless it's not there
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then just return none, or something to this effect.
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There's some cool little helper functions
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that we might want to pass along
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and if they're in this code or we have access to them
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in this code, we could actually say
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helper function a equals just the name of the function
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and that's also available to our template.
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This could be data or behavior
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we need to pass along to our view.
