Building data-driven web apps with Flask and SQLAlchemy Transcripts
Chapter: Jinja2 templates
Lecture: Demo: @response a better render_template
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Now lets look at our views so far here
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we've got our index, and we've got our about
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I'm not a huge fan of calling flask.render_template
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all of this, all the time.
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What I'd rather do is just say
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do something like this, return
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packages, test-test packages.
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Just return some kind of dictionary
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that we can get from some model classes or
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other sorts of transformations that we want to make.
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And just send those back
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and have it just somehow know, use index.
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Would be nice if that was named home
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and that's named index, it would just magically find it.
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You know maybe we could actually
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write some code that'll work, and do that.
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But we're going to do a little bit of a, change here.
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So if you go and look at the Flask documentation they
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talked about different ways in which to do this.
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And here's one that I came up with
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and they talk about it about it as well.
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And what I'm going to do is
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I'm going to use a decorator to specify, like at response.
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And then I'll say, you know
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something like, that right there.
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And then we're just going to return this.
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Okay, so, come down here like so.
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I know what I want to do is I want to make a folder, that holds
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a bunch of these little utility pieces and whatnot.
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So I'm going to call this, actually
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going to go up here, and run that.
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Create a directory called, infrastructure.
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Like so, and this is some pretty touchy
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and not fun to write code.
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So let's go just copy and paste
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and have a quick look at it.
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So here MIME type is just a variable name
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that Hydron thought was misspelled, it's not.
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There's a little diagnostics for you.
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So what we're going to do is we're
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this decorate called, response.
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And it takes only keyword arguments
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that means you cannot pass positional arguments.
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And it's a function we call that returns
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a decorated that just wraps any function
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that takes any arguments, using itertool wraps
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so you get the right error
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error handling, error reporting and other info.
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And then it's going to go in it says "Look
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if it's a response just return it.
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But if it's a dictionary
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then we're going to go and actually find the template file
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and just do render to template, back."
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Also lets you set the MIME type
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because that's not super easy to do as well.
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We're going to go over here
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and now if we just import this, at the top
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let me see if I can have it all with that thing.
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Now we can say response, and this has a keyword only
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so if you do it like this
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and let's go down here like this one.
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And say this one is just home-about.
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There's nothing interesting going on to that one.
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And then we can just say "Return, empty dictionary."
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You may like this, you may not like this, right?
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It's up to you I personally like to specify
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this is the page and then only return the data.
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You'll see in a real page
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like you'd have this repeated three
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or four times potentially.
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In, uh more complicated ones.
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So I don't like that, not much at all.
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So this is the way I'm going to do it.
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Maybe I'll leave this one here
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well at least in this chapter so you can see.
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So let's see if I broke it or if it still works.
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That's the first one to see if it's a good idea.
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Hey look at that, that looks a whole lot like that homepage
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that looks like the about page.
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Pretty cool, huh?
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Well I feel like this definitely simplifies this.
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Like I said it's again
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a little simple to really appreciate it
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But when you have like, some conditions
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and some tests, you want to return
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you want to render that over and over
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but with different data like
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"No you didn't submit the form right.
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Here's the same page but different data."
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So like with an error message or something.
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This mode here can get super tedious.
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So I'm a fan of this, optional but if you like it
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it's going to be in the code and you can take it with you.
