1 00:00:05,570 --> 00:00:06,560 Welcome back. 2 00:00:06,560 --> 00:00:11,960 To finish off this section of the API we're going to show you how to connect the actual things like 3 00:00:12,020 --> 00:00:15,250 get posts and delete methods to a database. 4 00:00:15,260 --> 00:00:20,300 So far we've been dealing with things just held temporarily in memory such as a list. 5 00:00:20,300 --> 00:00:24,800 So what we're going to do is we're going to convert our previous guest posts and delete methods inside 6 00:00:24,860 --> 00:00:29,810 of our rest a resource class and we're going to use it to actually change his methods to grab objects 7 00:00:30,050 --> 00:00:31,550 from a database. 8 00:00:31,550 --> 00:00:36,140 So all we really need to do is create a model and then replace the methods with what we've already learned 9 00:00:36,200 --> 00:00:39,860 about basic applications of sequel alchemy based models. 10 00:00:39,860 --> 00:00:42,770 Essentially we're really not going to learn anything new in this lecture. 11 00:00:42,770 --> 00:00:48,750 We're just going to see how to connect what we already know about basic crud with models to our rest 12 00:00:48,800 --> 00:00:51,030 API functionalities that we just learned. 13 00:00:51,050 --> 00:00:53,870 So we're going to work at the same files as we did in the previous lecture. 14 00:00:53,900 --> 00:00:56,580 We're just going to create a model and then edit the methods. 15 00:00:56,720 --> 00:00:58,040 Let's get started. 16 00:00:58,060 --> 00:00:58,400 OK. 17 00:00:58,400 --> 00:01:01,310 Here we are at our simple API that py file. 18 00:01:01,400 --> 00:01:06,260 We're going to keep the same files for secure check as well as user pie. 19 00:01:06,260 --> 00:01:10,700 Keep in mind if you want to expand on what we're showing in this lecture you could convert this user 20 00:01:10,700 --> 00:01:16,460 to be a model itself and then just call those models from the secure check file and set of these tables. 21 00:01:16,490 --> 00:01:22,310 But really what we want to focus on are these three methods right here get post and delete. 22 00:01:22,450 --> 00:01:27,560 And essentially all we need to do is connect these to the methods that we already learn when manipulating 23 00:01:27,560 --> 00:01:29,980 models and databases with flask. 24 00:01:29,990 --> 00:01:34,640 So in order to do that let's go ahead and create a flask model. 25 00:01:35,000 --> 00:01:42,600 So we're going to say up at the top from flask sequel alchemy import sequel alchemy. 26 00:01:42,620 --> 00:01:43,880 So nothing new here. 27 00:01:44,000 --> 00:01:50,950 And we're also going to use flask Miree so say from flask migrate import migrate. 28 00:01:51,170 --> 00:01:54,390 So we've seen all that before we set up our app. 29 00:01:54,440 --> 00:01:58,160 We set up our configurations and we have a couple of more configurations to set up. 30 00:01:58,280 --> 00:02:04,380 And these are the ones related to our model so say base directory is equal to OS path. 31 00:02:05,430 --> 00:02:06,770 Absolute path. 32 00:02:07,200 --> 00:02:13,370 And then inside of that we'll say OS path directory name and then we'll pass and file. 33 00:02:13,650 --> 00:02:19,070 So we do this every time that we create models and then we'll set up the configurations for the model. 34 00:02:19,380 --> 00:02:26,290 So one will be sequel alchemy underscore database underscore. 35 00:02:26,330 --> 00:02:27,070 You are. 36 00:02:27,210 --> 00:02:31,250 I will set that equal to sequel. 37 00:02:31,360 --> 00:02:36,830 Colon three forward slashes plus OS not path. 38 00:02:36,890 --> 00:02:40,960 Join and join that base directory. 39 00:02:41,060 --> 00:02:42,320 Data sequel. 40 00:02:42,470 --> 00:02:47,240 Essentially saying go ahead and create that database you or I in the same location that we're currently 41 00:02:47,240 --> 00:02:48,160 in. 42 00:02:48,180 --> 00:02:52,200 They'll say app config and then will say sequel. 43 00:02:52,220 --> 00:03:02,660 Alchemy again underscore track modifications and we'll set that equal to false. 44 00:03:02,730 --> 00:03:05,400 OK so we have our configuration set up. 45 00:03:05,520 --> 00:03:12,810 Next we're going to do is we'll say D-B is equal to sequel alchemy in our app and then we want to be 46 00:03:12,810 --> 00:03:15,040 able to call the migrations from the command line. 47 00:03:15,150 --> 00:03:18,700 So say migrate Hassen the app to connect it to the database. 48 00:03:19,140 --> 00:03:19,770 Okay perfect. 49 00:03:19,770 --> 00:03:26,880 So this takes care of our database configurations and this takes care of our API as well as authentication. 50 00:03:26,880 --> 00:03:31,680 Now what we need to do is instead of storing things in this puppy's list to create a section here for 51 00:03:31,680 --> 00:03:34,050 the model and we're doing this all in one file. 52 00:03:34,050 --> 00:03:39,840 You could just create an other file called models that Pizer them in the past and import it from there. 53 00:03:39,950 --> 00:03:40,990 We'll keep things simple. 54 00:03:41,010 --> 00:03:53,710 We'll just say class puppie say D-B model and then here will say name is equal to D-B column and. 55 00:03:53,910 --> 00:03:59,120 But Beezer is going to have a name that's a string type column let's say 80 characters is the limit 56 00:03:59,510 --> 00:04:01,610 and we'll just have this be their primary key. 57 00:04:01,880 --> 00:04:06,350 Obviously you could expand this to whatever you wanted it could have IDs breeds and so on is it done 58 00:04:06,350 --> 00:04:07,390 before. 59 00:04:07,420 --> 00:04:19,300 So we have the name will say in its self common name and we'll just say when you create a puppy give 60 00:04:19,300 --> 00:04:20,290 that puppy a name. 61 00:04:20,650 --> 00:04:24,160 And in this case it's a little unrealistic because every puppy has to have a unique name. 62 00:04:24,160 --> 00:04:32,100 So but what really need to worry about the IDs here we'll just say DFI Jaison because we want to do 63 00:04:32,160 --> 00:04:37,680 is when we have an instance of a puppy we can actually return back a puppy instance with flasks. 64 00:04:37,710 --> 00:04:43,920 API are not going understand that we return back something that basically looks like adjacent objects 65 00:04:43,920 --> 00:04:52,640 so when we say def Jaison return we're going to say return back name with self-taught name. 66 00:04:52,920 --> 00:04:57,450 So when we actually return calls we're not going to return a puppy object we're gonna get that puppy 67 00:04:57,450 --> 00:05:03,420 object and then called J son off of it in order to return a on a representation of the object. 68 00:05:03,480 --> 00:05:06,440 And if we have more stuff here you could say then breed. 69 00:05:06,780 --> 00:05:07,940 Self-taught breed. 70 00:05:08,400 --> 00:05:09,290 And so on. 71 00:05:09,300 --> 00:05:14,460 There's actually lots of examples like this in the flask restful documentation and at the very end we'll 72 00:05:14,460 --> 00:05:15,970 kind of show you some of those as well. 73 00:05:16,860 --> 00:05:17,390 OK. 74 00:05:17,680 --> 00:05:21,610 So we have this puppy model we initiated and then we have the Jason. 75 00:05:21,670 --> 00:05:27,280 So now when you do just go through the method calls and fix them so they are actually linking to this 76 00:05:27,280 --> 00:05:28,540 model. 77 00:05:28,540 --> 00:05:32,830 So if we want to grab something from a model database then we already know what we need to do. 78 00:05:33,160 --> 00:05:37,350 We need to basically not have this list for that anymore. 79 00:05:37,420 --> 00:05:46,610 We'll say pup is equal to puppy and we run a query that also filter by name is equal to name and then 80 00:05:46,610 --> 00:05:52,370 grab the first one and then if we actually get a puppy out we'll say if there's a puppy return. 81 00:05:52,370 --> 00:05:58,820 So if pup return pup Jaison and that's where it's really nice to have that Jason method built into the 82 00:05:58,820 --> 00:05:59,830 model class. 83 00:05:59,870 --> 00:06:04,280 So I would recommend that you're building up models and you think rest API is going to be a big part 84 00:06:04,280 --> 00:06:05,210 of your web site. 85 00:06:05,210 --> 00:06:09,140 Go ahead and add in that Jason method call built into the model. 86 00:06:09,360 --> 00:06:09,930 OK. 87 00:06:10,040 --> 00:06:11,420 So else. 88 00:06:11,510 --> 00:06:12,720 So there's no puppy there. 89 00:06:13,620 --> 00:06:14,970 We're just going to say return. 90 00:06:15,150 --> 00:06:16,930 Name none 404. 91 00:06:16,940 --> 00:06:17,160 OK. 92 00:06:17,190 --> 00:06:18,170 So that's our simple guess. 93 00:06:18,190 --> 00:06:22,980 Again we just filter by whatever unique identifier primary key you have and then return that based on 94 00:06:22,980 --> 00:06:25,290 version for a posting. 95 00:06:25,390 --> 00:06:29,430 It's going to be kind of similar to what we've done before we'll say pup is equal to. 96 00:06:29,590 --> 00:06:33,030 And then here we're going to do is create a new instance of a puppy. 97 00:06:33,470 --> 00:06:35,370 Her name is equal to name that's passed in. 98 00:06:35,380 --> 00:06:43,050 When someone's posting a request and they will say D-B session go ahead and add that up and then grab 99 00:06:43,050 --> 00:06:50,860 D-B session and then go ahead and commit the changes and then we're just going to return d.j some version 100 00:06:50,860 --> 00:06:55,850 of the pup as essentially a confirmation that hey we added it and then we're putting them in the j's 101 00:06:55,850 --> 00:07:01,220 on OK then for deleting a puppy or we're going to do here. 102 00:07:03,050 --> 00:07:11,290 Say pup is equal to essentially the same command so we therefore queery filter by then we're going to 103 00:07:11,290 --> 00:07:18,640 filter by name as equal to name grab the first one that shows up grab or database session and then we'll 104 00:07:18,640 --> 00:07:21,650 just call delete that pup and then commit that delete. 105 00:07:21,670 --> 00:07:28,480 So say D-B session commit that delete and then we're just going to actually and overturn the same thing 106 00:07:28,480 --> 00:07:29,360 it did before. 107 00:07:29,530 --> 00:07:32,410 We'll just go ahead and return hey little success. 108 00:07:32,430 --> 00:07:35,930 OK so last one for all names though. 109 00:07:35,950 --> 00:07:37,450 We can do that is if you want. 110 00:07:37,450 --> 00:07:40,140 You can authenticate this or not authenticate this. 111 00:07:40,150 --> 00:07:44,800 Let's go ahead and just cancel out that authentications we won't worry about it for guess what we're 112 00:07:44,800 --> 00:07:54,170 going to do here is we're going to say puppies is equal to puppy and then we can say queery all in order 113 00:07:54,170 --> 00:07:55,930 to grab every single puppy. 114 00:07:55,940 --> 00:07:59,320 So keep in mind this is going to be a list of puppy objects. 115 00:07:59,330 --> 00:08:04,730 And as I mentioned we can actually return puppy objects when we return the Jason version of them. 116 00:08:04,730 --> 00:08:13,990 So what we need to do here is I can use list comprehension to say pup Jason for pup in puppies because 117 00:08:13,990 --> 00:08:16,020 this list of puppies is just a bunch of puppy objects. 118 00:08:16,030 --> 00:08:21,110 So going to return them all is based on in this giant list and then return that for all the names. 119 00:08:21,400 --> 00:08:21,930 OK. 120 00:08:22,210 --> 00:08:23,770 So we could keep everything else the same. 121 00:08:23,770 --> 00:08:26,120 And now we've connected this two models. 122 00:08:26,140 --> 00:08:29,980 So really this should just serve as a reference for you when you want to add in rest. 123 00:08:29,980 --> 00:08:35,380 API calls quickly using this resource method you can already have your existing projects that we've 124 00:08:35,380 --> 00:08:38,780 already done throughout the course and then just add these special methods. 125 00:08:38,800 --> 00:08:45,100 OK the final step though we have to do here is actually register our model using the migrations. 126 00:08:45,100 --> 00:08:51,470 So if you call flask D-B in it as you've done before and enter you may actually get an error the pinning 127 00:08:51,480 --> 00:08:52,790 on what you named your file. 128 00:08:52,960 --> 00:08:57,460 So if you named your file something other than look at that pie it may say something like Hey I couldn't 129 00:08:57,460 --> 00:08:59,000 locate that flask application. 130 00:08:59,170 --> 00:09:02,090 You forgot to provide that flask app environment variable. 131 00:09:02,110 --> 00:09:05,740 So we've seen this before we actually had a whole discussion on this and you can go back to the models 132 00:09:05,740 --> 00:09:06,960 lecture's to see it. 133 00:09:07,050 --> 00:09:14,830 All we need to do here is depending on your operating system you're either going to say export flask 134 00:09:14,950 --> 00:09:20,160 app equal to and then the name of your application so simple API that pie. 135 00:09:20,380 --> 00:09:21,300 So you can run that. 136 00:09:21,370 --> 00:09:24,490 However export that's for a Mac OS or Linux computers. 137 00:09:24,610 --> 00:09:31,720 If you're running a Windows like I am here going to say set flask at equal to and in this case you just 138 00:09:31,780 --> 00:09:33,610 choose it over the python. 139 00:09:34,000 --> 00:09:39,920 So now I've said it so that my environment variable tickly can also find Python with some OS calls. 140 00:09:40,000 --> 00:09:41,000 But we've done that. 141 00:09:41,050 --> 00:09:43,670 We definitely seen this before so check back the models lecture's. 142 00:09:43,680 --> 00:09:46,560 If you don't remember this error there's a whole discussion about it in the notes. 143 00:09:46,690 --> 00:09:53,140 But once you've done that then we can run flask VB in it enter and it looks like we forgot one thing 144 00:09:53,140 --> 00:09:54,790 which was to import os. 145 00:09:54,880 --> 00:09:58,460 So let's go ahead and add that in so say. 146 00:09:58,490 --> 00:09:59,720 Import os. 147 00:09:59,740 --> 00:10:00,510 Say that. 148 00:10:00,580 --> 00:10:04,640 That would make sense because we have those OS calls plus the BE IN IT. 149 00:10:04,730 --> 00:10:10,820 Ok that looks like it ran correctly will say Flast DBI migrates and then just have a little message 150 00:10:10,820 --> 00:10:11,300 here. 151 00:10:11,310 --> 00:10:18,140 The quotes will say first migration or first migrate they enter the migrations occur centrally adding 152 00:10:18,140 --> 00:10:25,550 in that name column for the puppy and then to make these actually happen say Flast DBI upgrade hit enter 153 00:10:25,980 --> 00:10:27,670 and now our database should exist. 154 00:10:27,710 --> 00:10:32,300 And if you open up this Left-Hand tab you should now see somewhere here like a folder for migrations 155 00:10:32,330 --> 00:10:36,860 and the data that sequel like nothing you definitely done this before many times throughout the course 156 00:10:37,260 --> 00:10:42,820 and Altes actually run our simple API OK it looks like everything's running. 157 00:10:42,960 --> 00:10:47,550 Let's go ahead and see if we can add puppies and puppies and read all the puppies and that will be the 158 00:10:47,550 --> 00:10:49,980 end of this so let's open up postman. 159 00:10:49,980 --> 00:10:51,960 So here I have postman open. 160 00:10:51,960 --> 00:10:55,510 First thing I'm going to do is I'm actually going to try to post the puppy. 161 00:10:55,740 --> 00:11:00,520 Right now nothing is authorized or nothing requires authorization as such thing. 162 00:11:00,630 --> 00:11:03,540 So let's go ahead and add in Sammy to the database. 163 00:11:03,540 --> 00:11:10,440 Keep in mind now that we're using a real database I can add in the puppies and then close off my Python 164 00:11:10,620 --> 00:11:14,620 script and then run my Python script again and the puppies will still be in that database. 165 00:11:14,640 --> 00:11:19,230 Unlike before where every time you restarted your python script that list was completely wiped out because 166 00:11:19,230 --> 00:11:20,050 it was in memory. 167 00:11:20,160 --> 00:11:24,020 Now we're actually dealing with something that's more secure and more permanent. 168 00:11:24,120 --> 00:11:27,210 So we're going to add in puppies so let's send the request. 169 00:11:27,380 --> 00:11:29,120 We got named Sammy so it looks good. 170 00:11:29,130 --> 00:11:35,180 It's going an add in Franki as well so I'll say Franki send it. 171 00:11:35,220 --> 00:11:37,560 We get back Franki So looks like that's working. 172 00:11:37,560 --> 00:11:39,130 Let's go ahead and get the puppies. 173 00:11:39,320 --> 00:11:41,750 So I'll say get all the puppies. 174 00:11:41,760 --> 00:11:42,540 Let's see if this works. 175 00:11:42,540 --> 00:11:48,220 Remember I commented out the authorization and it looks like that's working as well named Sammy named 176 00:11:48,230 --> 00:11:48,610 Frankie. 177 00:11:48,640 --> 00:11:51,670 That's working well let's try deleting a puppy. 178 00:11:51,760 --> 00:12:00,020 So say delete or say puppy and let's go ahead and delete Sammy will send that. 179 00:12:00,020 --> 00:12:03,010 Looks like the delete was successful so that method also worked. 180 00:12:03,020 --> 00:12:07,890 Let's get all the puppies again and see if it was actually removed from that database. 181 00:12:08,270 --> 00:12:09,260 So I'll send that. 182 00:12:09,290 --> 00:12:11,870 Looks like we only get back Franki So that's working well. 183 00:12:12,030 --> 00:12:17,510 OK so it looks like we were able to test out the commands for getting posting puppies grabbing all the 184 00:12:17,510 --> 00:12:19,200 puppies and deleting puppies. 185 00:12:19,400 --> 00:12:24,620 And if you want to update the puppies all you need to do is add in a method call called Put And then 186 00:12:24,620 --> 00:12:29,450 just use the update methods that we've already gone through multiple times throughout the course. 187 00:12:29,450 --> 00:12:34,190 Now something I want to mention is that the flask restful documentation actually has some really nice 188 00:12:34,190 --> 00:12:36,310 examples for you to check out. 189 00:12:36,410 --> 00:12:42,710 So if you come over to flask restful and expand this here you can check out the Quixtar but you can 190 00:12:42,710 --> 00:12:47,240 also scroll down and then check out the zoom in here. 191 00:12:47,300 --> 00:12:52,340 They have a bunch of examples that you can then extend flask restful intermediate users usage for Project 192 00:12:52,340 --> 00:12:53,010 structures. 193 00:12:53,120 --> 00:12:55,450 How you can use blueprints and so on. 194 00:12:55,490 --> 00:12:59,630 There's lots of really good resources here and I would really recommend you just check out the QuickStart 195 00:12:59,630 --> 00:13:05,030 guide and then go through out these different examples here because they're really useful as far as 196 00:13:05,120 --> 00:13:07,620 learning how to deal things like formatting. 197 00:13:07,640 --> 00:13:12,170 You know they have different full examples here that have an example here which is kind of a To Do list. 198 00:13:12,170 --> 00:13:17,030 You can then build off of and you can play around with this so this one page has lots of examples and 199 00:13:17,030 --> 00:13:19,300 the documentation is just pretty good in general. 200 00:13:19,340 --> 00:13:22,490 OK so that's it for flask restful applications. 201 00:13:22,490 --> 00:13:23,740 I hope you found that useful. 202 00:13:23,840 --> 00:13:25,340 And hope is a good jumping off point. 203 00:13:25,370 --> 00:13:30,630 In case you intend to use flask rest for any of your future projects we'll see at the next one.