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Welcome everyone to this lecture on redirects.

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Sometimes a client user is going to provide a path that we want to redirect to another webpage on our

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site.

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This can actually be accomplished in Django through the use of the HTP response redirect function.

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Let's imagine in our example of the website newspaper that we actually want to match the article pages

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on the website to the numeric page in the physical newspaper that is that paper newspaper for readers

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to actually find an article online.

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For example, let's imagine a user has the physical newspaper in their hands and they're turning the

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pages and they see Page two is finance.

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Well, we would want them to be able to do is go to our website and then go to the first app for slash

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two for that page number and then be redirected to first app forward slash finance.

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So what we're going to do is show you how you could do that sort of redirect with Django, with what

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we know so far.

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Now an important note, the example we're going to show here is actually another typical way we'll redirect

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pages.

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We still need to learn about the reverse function, and you are all names and templates to really bring

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this to a more robust way of redirecting.

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In fact, what we're going to do right now has a significant flaw or error, which we'll talk about

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in the lecture, and we'll actually induce it and then move on to the next lecture where we attempt

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to fix this sort of conundrum.

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But for right now, we're going to explore a very simple redirect syntax example, and we'll discuss

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some more details behind it in the next lecture with reverse and neural names.

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For now, let's head to our code editor and show you a simple redirect.

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OK, so here I am at my views file and I also have URLs file underneath first app.

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And essentially, what I want to do is create a view that can do the following If somebody were to type,

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let's say domain that.

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Com first app for its flash and then a zero, for instance, that would get redirected to the correct

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corresponding topic.

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So we are domain first app and then it would get redirected to something like finance or sports, etc.

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So we're going to do is convert these keys into a list of topics and let's begin by creating our function.

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So I'll have this be called number page view or NUM page view.

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It takes in a request, as well as the number page that somebody asked for.

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So we'll say in some pages Peston.

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And then we want to do here is the following I want to grab all these keys from articles and create

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a list from that.

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So we're going to say that our.

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Topics list.

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So topics list is equal to a list of articles, keys.

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OK, so we grab all the keys from that articles dictionary, create a list out of it, and this essentially

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looks something like this.

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It's going to be sports, comma, finance, comma and then the last string will be politics if we get

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our order correct?

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Yeah.

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Sports, finance, politics.

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So this topics list essentially looks something like this, which means I have the indices zero, one

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and two for right now.

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We're going to assume that a user is actually going to pass in the correct number page.

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So from there, the actual topic that we want to look at would be our topics list.

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At the index location for that particular number page and then we want to do is the actual idea of the

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redirect.

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So I can't really just send them to this page because that page doesn't really exist.

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I want to send them finally to this page that has the topic name.

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So I end up doing is first off, I have to make sure that I import.

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If we go all the way up here and import HTP Response Redirect, which allows me to redirect to another

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page on my website.

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So also, you get the topic, I'm going to say return.

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HDP response.

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Redirect.

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And then we're going to redirect.

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To the topic, so we're going to save that change right now, something to do is take into account the

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fact that we need to be able to actually search for this URL first before we start searching for this

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one, which means I need to go to URLs that pie and set up that path.

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So the first item in this URL patterns list is going to be path.

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And then inside the string, I'm going to insert as an integer.

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That particular page numb, let me check A's page on her page.

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No, it was actually no page, so we'll switch that it's numb, underscore page.

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So that's being passed in and then I want that connected to views, dots and then it's the number of

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page views.

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So page view.

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Comma, there we go, so now that's our new URL patterns.

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Go ahead and save that change.

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And let me walk through what's going to happen.

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So let's imagine a user literally types out this into your website.

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Well, that ends up getting matched up with this path first, which means it then goes to our no page

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view.

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We look at that number page, look up the corresponding topic and then redirect to topic, which actually

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ends up redirecting to this particular website page that looks something like first app for large topic,

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which would then actually connect to this URL pattern to redirect to finally show, hopefully the correct

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HTP response.

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Again, something to keep in mind.

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We're going to assume that they're going to pass in the correct index here.

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Otherwise, you could always just raise a 404 error.

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OK, so let's say these changes and make sure this is all working.

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So I'm going to say Python managed up high.

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I will run the server.

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There we go.

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So it's running right now.

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I'm going to go to my homepage.

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I'm bringing my browser, so I have home view.

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I'll go to forward slash first app and let's check to make sure just let's say finance is working.

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So I hit there.

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I get finance on the finance page and let's see what happens if I say first app, forward slash, for

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example.

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One Enter.

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And notice that we'll get redirected.

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Let's do it for another number like zero.

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Enter that gets redirected to sports page and then first app forward slash to gets redirected to politics.

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If I do a number that's outside of that, like 100, I get this hate index error, which is kind of

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interesting.

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So List Index is out of range because there is no Index 100 here inside of that list.

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So what I could do is come back to my one page view and essentially put this entire block of code inside

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a try block and then have a four or four or redirect or some auto response if there was an error there.

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So again, we can always incorporate what we've learned so far to fix that issue of that number page

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not showing up.

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The major issue right now is the fact that this is still a little too hard coded in as a redirect,

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especially when we start introducing templates.

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What I would really like to take advantage of is the fact that I can name you URLs and use what's known

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as the reverse function to try to make this entire redirect process a lot more robust instead of having

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to remember all these hardcoded topics and create a view like this.

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So we're going to do is expand on this idea with redirects, as well as the reverse functionality in

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the very next lecture, and we'll show you essentially how to do this correctly, so to speak.

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So let's talk about that in the next lecture.