1 1 00:00:01,360 --> 00:00:02,570 Hi and welcome back. 2 2 00:00:02,570 --> 00:00:04,330 In this video we're going to talk about 3 3 00:00:04,330 --> 00:00:07,080 how to display only the alerts that are 4 4 00:00:07,080 --> 00:00:09,500 for the currently logged in user. 5 5 00:00:09,500 --> 00:00:12,623 So that not all users will see all alerts. 6 6 00:00:13,610 --> 00:00:16,630 We're gonna start by going over to the alerts view, 7 7 00:00:16,630 --> 00:00:20,350 and we're gonna make a small change in the index. 8 8 00:00:20,350 --> 00:00:23,480 Instead of retrieving all the alerts in our system, 9 9 00:00:23,480 --> 00:00:25,920 we're only going to retrieve those alerts 10 10 00:00:25,920 --> 00:00:30,183 that have a property that matches session email. 11 11 00:00:31,160 --> 00:00:33,540 So if you remember, whenever the user logs in 12 12 00:00:33,540 --> 00:00:36,733 or registers, we set session email. 13 13 00:00:37,610 --> 00:00:40,110 And we know that this session is related to a 14 14 00:00:40,110 --> 00:00:44,240 particular user because every browser will send us a cookie, 15 15 00:00:44,240 --> 00:00:47,220 a piece of data that tells us which session 16 16 00:00:47,220 --> 00:00:49,830 that browser is related to. 17 17 00:00:49,830 --> 00:00:52,600 So when the user logs in with their browser 18 18 00:00:52,600 --> 00:00:55,070 that cookie will then be related to one 19 19 00:00:55,070 --> 00:00:58,760 specific session which will contain their email. 20 20 00:00:58,760 --> 00:01:02,490 If many users sign up, there'll be many cookies, 21 21 00:01:02,490 --> 00:01:04,020 and when we receive those cookies, 22 22 00:01:04,020 --> 00:01:07,380 we'll be able to determine which session is for who. 23 23 00:01:07,380 --> 00:01:09,980 So that's sort of how the log in works just as a recap. 24 24 00:01:09,980 --> 00:01:11,430 And here what we're gonna do is we're gonna 25 25 00:01:11,430 --> 00:01:14,513 retrieve alerts that match that session's email. 26 26 00:01:15,420 --> 00:01:19,880 So we're say find many by and we're gonna say 27 27 00:01:19,880 --> 00:01:21,237 the attribute is user email, 28 28 00:01:21,237 --> 00:01:23,840 and the value is session email. 29 29 00:01:23,840 --> 00:01:26,440 So what this is gonna do, gonna go to the database 30 30 00:01:26,440 --> 00:01:30,180 and find all the alerts that have a property 31 31 00:01:30,180 --> 00:01:34,830 user_email and that value is session email. 32 32 00:01:34,830 --> 00:01:38,250 So if somebody logs in with Bob@example.com, 33 33 00:01:38,250 --> 00:01:39,560 then we're only gonna show alerts 34 34 00:01:39,560 --> 00:01:41,370 that have a property user email 35 35 00:01:41,370 --> 00:01:43,963 with value Bob@example.com. 36 36 00:01:45,050 --> 00:01:46,750 This does mean two things. 37 37 00:01:46,750 --> 00:01:49,210 The first thing it means is we need to add 38 38 00:01:49,210 --> 00:01:53,068 a property user_email to our alert. 39 39 00:01:53,068 --> 00:01:54,980 And the second thing it means is the user 40 40 00:01:54,980 --> 00:01:58,260 must've logged in or registered in order 41 41 00:01:58,260 --> 00:02:00,863 for session email to have a value. 42 42 00:02:02,130 --> 00:02:05,310 Let's go over to our alert model 43 43 00:02:05,310 --> 00:02:07,530 and add a couple of those things in. 44 44 00:02:07,530 --> 00:02:10,640 In order to add a new property to our alert, 45 45 00:02:10,640 --> 00:02:14,060 all we have to do is say user_email is a string. 46 46 00:02:14,060 --> 00:02:16,030 And we don't have to give it any extra values. 47 47 00:02:16,030 --> 00:02:19,723 That's automatically gonna go into the init method. 48 48 00:02:20,610 --> 00:02:22,830 Then we're gonna do self.user is 49 49 00:02:22,830 --> 00:02:24,380 user.find_by_email(user_email). 50 50 00:02:29,818 --> 00:02:32,730 And of course we do need self, 51 51 00:02:32,730 --> 00:02:35,650 and we do need to import user 52 52 00:02:35,650 --> 00:02:39,303 from models user import user. 53 53 00:02:41,260 --> 00:02:42,620 And we also wanna be saving the 54 54 00:02:42,620 --> 00:02:44,793 user email in the json method. 55 55 00:02:49,120 --> 00:02:51,520 Alright, so that's everything we need from 56 56 00:02:51,520 --> 00:02:55,270 our alert model in order to add this new field. 57 57 00:02:55,270 --> 00:02:56,660 Now we do need to remember to 58 58 00:02:56,660 --> 00:02:59,030 pass in a value to the constructor. 59 59 00:02:59,030 --> 00:03:02,010 So going back to our view here in the 60 60 00:03:02,010 --> 00:03:04,320 alert constructor when we create a new alert, 61 61 00:03:04,320 --> 00:03:08,140 we do have to pass in session email. 62 62 00:03:08,140 --> 00:03:11,410 Note that this automatically means that 63 63 00:03:11,410 --> 00:03:13,370 in order to create a new alert, 64 64 00:03:13,370 --> 00:03:15,750 a user has to have logged in previously, 65 65 00:03:15,750 --> 00:03:17,270 otherwise this won't have a value 66 66 00:03:17,270 --> 00:03:18,683 when they make this request. 67 67 00:03:19,760 --> 00:03:21,300 Later on in the course, we're gonna talk about 68 68 00:03:21,300 --> 00:03:24,140 how we can make sure that users are logged in 69 69 00:03:24,140 --> 00:03:27,140 and how to request that they log in if they haven't already. 70 70 00:03:29,110 --> 00:03:31,030 In the edit alert, we're not going to use 71 71 00:03:31,030 --> 00:03:33,200 session email at all because all that's changing 72 72 00:03:33,200 --> 00:03:34,193 is the price limit. 73 73 00:03:35,080 --> 00:03:37,340 Again in the later video we will require 74 74 00:03:37,340 --> 00:03:40,220 users to log in before they can edit an alert 75 75 00:03:40,220 --> 00:03:42,020 just in case they try editing an alert 76 76 00:03:42,020 --> 00:03:44,330 that's not theirs, but at the moment 77 77 00:03:44,330 --> 00:03:45,680 we're not going to do that. 78 78 00:03:47,440 --> 00:03:51,390 In the delete alert we are going to go ahead and 79 79 00:03:51,390 --> 00:03:54,920 make sure that the alert that is to be deleted 80 80 00:03:54,920 --> 00:03:58,180 is the user's alert and not somebody else's. 81 81 00:03:58,180 --> 00:03:59,070 This is something that you could do 82 82 00:03:59,070 --> 00:04:00,780 in the edit alert as well if you wanted. 83 83 00:04:00,780 --> 00:04:01,960 So I'll just show it to you here, 84 84 00:04:01,960 --> 00:04:04,500 and you can choose what you want to do. 85 85 00:04:04,500 --> 00:04:07,150 The first thing we're gonna do is put the alert 86 86 00:04:07,150 --> 00:04:08,860 into its own variable 87 87 00:04:10,190 --> 00:04:15,190 and then if the alert user email matches sessions email 88 88 00:04:17,300 --> 00:04:20,313 then we're going to do alert.remove from mongo. 89 89 00:04:21,570 --> 00:04:25,290 Okay perfect. 90 90 00:04:25,290 --> 00:04:26,600 That's everything we need in order 91 91 00:04:26,600 --> 00:04:30,680 to have the alerts showing up only per user. 92 92 00:04:30,680 --> 00:04:32,920 There are a couple of things you have to do 93 93 00:04:32,920 --> 00:04:34,760 before you run your app. 94 94 00:04:34,760 --> 00:04:36,430 Well, you can do them after you run your app, 95 95 00:04:36,430 --> 00:04:38,690 but I would recommend you do them before 96 96 00:04:38,690 --> 00:04:40,870 which is you have to go and clear 97 97 00:04:40,870 --> 00:04:42,633 everything from your database. 98 98 00:04:43,500 --> 00:04:45,550 Okay, so I've loaded up mungo DB here. 99 99 00:04:45,550 --> 00:04:48,173 Make sure you're using the right database. 100 100 00:04:49,980 --> 00:04:51,610 And then we're just gonna delete everything 101 101 00:04:51,610 --> 00:04:53,050 from the entire database. 102 102 00:04:53,050 --> 00:04:58,050 DB alerts remove, DB items remove, DB stores remove. 103 103 00:05:00,590 --> 00:05:02,500 Actually we're not gonna remove stores. 104 104 00:05:02,500 --> 00:05:04,420 We do wanna keep that just so that 105 105 00:05:04,420 --> 00:05:06,620 we don't have to delete them again. 106 106 00:05:06,620 --> 00:05:09,630 DB.users.remove. 107 107 00:05:09,630 --> 00:05:12,120 Okay, we've removed everything except the stores 108 108 00:05:12,120 --> 00:05:13,950 just because that is what has the technical 109 109 00:05:13,950 --> 00:05:16,270 data that we want to keep. 110 110 00:05:16,270 --> 00:05:20,570 And now we're ready to go ahead and create a new user 111 111 00:05:20,570 --> 00:05:24,240 and then create a new alert and see if all that works. 112 112 00:05:24,240 --> 00:05:26,303 Let's go ahead and run our app. 113 113 00:05:27,810 --> 00:05:30,140 I've brought up the app here on the right, 114 114 00:05:30,140 --> 00:05:31,623 and we're gonna sign up. 115 115 00:05:34,150 --> 00:05:35,320 There we have our user. 116 116 00:05:35,320 --> 00:05:37,480 Everything worked in there, and then 117 117 00:05:37,480 --> 00:05:40,190 we're gonna go over to the alerts endpoint. 118 118 00:05:40,190 --> 00:05:43,320 And you can see that it didn't fail. 119 119 00:05:43,320 --> 00:05:45,590 We're gonna create a new alert. 120 120 00:05:45,590 --> 00:05:47,100 And I found the item URL there, 121 121 00:05:47,100 --> 00:05:49,600 and then we've got our prize limit. 122 122 00:05:49,600 --> 00:05:51,230 So we're gonna create that 123 123 00:05:51,230 --> 00:05:52,700 and that also worked. 124 124 00:05:52,700 --> 00:05:53,810 What does that tell us? 125 125 00:05:53,810 --> 00:05:57,520 It means that we have session email set. 126 126 00:05:57,520 --> 00:06:02,470 So if we go back to alerts, we have our alert here. 127 127 00:06:02,470 --> 00:06:06,033 If we go and sign up as another user, 128 128 00:06:09,250 --> 00:06:11,865 and then we go over to our alerts, 129 129 00:06:11,865 --> 00:06:13,670 there are no alerts showing up. 130 130 00:06:13,670 --> 00:06:15,060 That's exactly what we wanted. 131 131 00:06:15,060 --> 00:06:18,023 Each user now has their own alerts. 132 132 00:06:19,040 --> 00:06:21,020 Do know that as we're navigating through this site 133 133 00:06:21,020 --> 00:06:24,240 we are strongly missing a navigation bar, 134 134 00:06:24,240 --> 00:06:26,140 something that we can use to move 135 135 00:06:26,140 --> 00:06:27,490 between our different pages. 136 136 00:06:27,490 --> 00:06:28,920 We're gonna be adding that later on, 137 137 00:06:28,920 --> 00:06:31,430 so don't worry if that's not there yet. 138 138 00:06:31,430 --> 00:06:33,260 Bootstrap actually has some very nice ways 139 139 00:06:33,260 --> 00:06:35,670 of adding navigation bars. 140 140 00:06:35,670 --> 00:06:37,040 That's everything for this video though. 141 141 00:06:37,040 --> 00:06:40,040 We have now made it so that the alerts 142 142 00:06:40,040 --> 00:06:42,490 only show up for the user that created them 143 143 00:06:42,490 --> 00:06:43,760 and not for anyone else. 144 144 00:06:43,760 --> 00:06:46,130 And we've also looked at how we can make sure 145 145 00:06:46,130 --> 00:06:48,520 that when we're interacting with a single alert 146 146 00:06:48,520 --> 00:06:50,500 that it is the right user 147 147 00:06:50,500 --> 00:06:52,100 that's making the interaction. 148 148 00:06:52,100 --> 00:06:53,830 And again, you can do this in the edit alert 149 149 00:06:53,830 --> 00:06:55,410 method as well if you wanted. 150 150 00:06:55,410 --> 00:06:57,680 But I just felt that the delete one is the 151 151 00:06:57,680 --> 00:06:59,780 one that's really important because 152 152 00:06:59,780 --> 00:07:01,820 it's the destructive action. 153 153 00:07:01,820 --> 00:07:03,870 This one will also need the user 154 154 00:07:03,870 --> 00:07:06,110 to log in before it runs. 155 155 00:07:06,110 --> 00:07:07,460 Thanks for joining me in this video! 156 156 00:07:07,460 --> 00:07:08,610 Hope you learned something 157 157 00:07:08,610 --> 00:07:10,260 and I'll see you on the next one.