1 00:00:01,170 --> 00:00:09,000 In this lecture, I'll show you how to send a dummy sensor data to do it, do it know it's just an example 2 00:00:09,000 --> 00:00:18,300 of how you can use the postdated bequest to send us from your especially to to pretty much any web resource 3 00:00:18,300 --> 00:00:22,400 that can receive data via a post hectically request. 4 00:00:23,220 --> 00:00:26,460 So the skips that I have prepared is this one here. 5 00:00:26,760 --> 00:00:31,310 It depends on its own credentials file, which you can see here. 6 00:00:31,590 --> 00:00:34,610 It's the same file that I showed you in the previous lecture. 7 00:00:34,620 --> 00:00:39,960 But in this case of edit, one more key value pair called thing. 8 00:00:40,230 --> 00:00:42,120 I talk about things in a moment. 9 00:00:42,130 --> 00:00:44,910 It's a term used in tweet IO. 10 00:00:45,120 --> 00:00:51,510 It's just a text file for a string value thereof stored here, and it's filename is in square brackets 11 00:00:51,510 --> 00:00:56,300 in the tab, which means that it's already uploaded onto my E.S.P 32. 12 00:00:56,340 --> 00:00:58,510 You can see it right here. 13 00:00:59,700 --> 00:01:00,810 Now back to the script. 14 00:01:01,650 --> 00:01:07,780 This script uses the same components as the one that you learned about in the previous lecture. 15 00:01:08,160 --> 00:01:17,460 So that is the network and your requests, the Jason to importing random, because I haven't got a actual 16 00:01:17,460 --> 00:01:23,220 sensor connected to my security, so I'll be simulating sensor data with random values. 17 00:01:24,800 --> 00:01:31,100 Before we have a look at the details here, let's go to the widowed IIO and have a look at that first. 18 00:01:31,670 --> 00:01:32,550 So do it. 19 00:01:32,610 --> 00:01:40,210 It is a very simple service which operates as a Twitter equivalent, but for machines. 20 00:01:40,580 --> 00:01:47,690 So Twitter is a service where you can send small messages about a couple of hundred characters at most, 21 00:01:48,080 --> 00:01:54,080 and imagine something similar for machines where a machine will be able to send a quick message to a 22 00:01:54,140 --> 00:01:59,420 tweet thing, which is an end point to a particular Eurail called a thing. 23 00:01:59,660 --> 00:02:08,990 And then other people will be able to access that same URL and read the data that the posting machine 24 00:02:09,290 --> 00:02:10,190 has posted. 25 00:02:10,730 --> 00:02:19,640 So if you go to do it today and then click on the play button, this is basically a single page tutorial 26 00:02:19,640 --> 00:02:21,320 on how to use tweet. 27 00:02:21,830 --> 00:02:26,590 I want to concentrate on this segment of this tutorial first. 28 00:02:26,590 --> 00:02:30,860 So see here, there's an example of how to make a post. 29 00:02:31,340 --> 00:02:38,390 So the URL here is the tweet for thing is a name for your machine. 30 00:02:38,840 --> 00:02:44,120 The thing that you machine is tweeting about, and it's a unique name across the tweet network. 31 00:02:44,510 --> 00:02:47,750 So you find a unique name for your thing. 32 00:02:47,930 --> 00:02:50,720 In my case, I call that you Python. 33 00:02:51,230 --> 00:02:57,410 And therefore the food you are real to which you want to post on your machine will post. 34 00:02:57,680 --> 00:03:00,950 Is this this one here? 35 00:03:00,950 --> 00:03:02,090 I've got the example. 36 00:03:02,480 --> 00:03:05,680 Do it or I'll add four, four, three. 37 00:03:05,690 --> 00:03:07,190 So I'm using SSL here. 38 00:03:07,880 --> 00:03:09,770 Do it for. 39 00:03:09,920 --> 00:03:11,090 And then the name of the thing. 40 00:03:11,090 --> 00:03:16,630 In my case I'm going to extract that from the potentials file which is going to be your python. 41 00:03:17,180 --> 00:03:28,580 So if I could say you python here, this is just an example using the tutorial form the key, I'm going 42 00:03:28,580 --> 00:03:29,660 to leave it as blank. 43 00:03:29,930 --> 00:03:38,570 So the way it allows you to purchase keys that allow you to create posts to things that are private, 44 00:03:38,810 --> 00:03:45,280 so only another machine with the appropriate key will be able to read the posts that you've made. 45 00:03:45,830 --> 00:03:50,840 I'm going to not use the key here and therefore my dweebs are going to be public. 46 00:03:51,380 --> 00:03:56,570 And for the content, we need to use Jason for the content here. 47 00:03:56,990 --> 00:04:05,120 Let's keep something very simple and then to go and grab this content here, something I did earlier 48 00:04:05,480 --> 00:04:07,430 and pasted it right there. 49 00:04:09,490 --> 00:04:18,670 And we'd expect the response that this has been has been a successful tweet and this is a response that 50 00:04:18,670 --> 00:04:25,920 comes back now, if I want to get this tweet mentioned, that another especially to someone else that 51 00:04:25,930 --> 00:04:36,280 will be able to receive data from my other remote, especially to all I need to do is to point the recipient, 52 00:04:36,280 --> 00:04:43,680 especially to to this Jerrell with this thing name and make a get request. 53 00:04:43,690 --> 00:04:47,350 You see here, it says get to do a get request here. 54 00:04:47,620 --> 00:04:49,290 And there's the data. 55 00:04:49,780 --> 00:04:54,550 So we thought it provides a very simple intermediary between machines. 56 00:04:55,330 --> 00:05:02,290 You could have one machine making a post and you could have many machines reading from the post, just 57 00:05:02,290 --> 00:05:03,520 like you've got with Twitter. 58 00:05:03,520 --> 00:05:10,660 You've got one person making a tweet and potentially millions of people receiving that tweet in their 59 00:05:11,080 --> 00:05:12,240 Twitter feed. 60 00:05:12,850 --> 00:05:14,890 So let's do it programmatically now. 61 00:05:15,250 --> 00:05:21,310 So I'm using the same construct here to open up the credentials file and get the credentials for the 62 00:05:21,310 --> 00:05:23,080 Wi-Fi network. 63 00:05:23,080 --> 00:05:30,010 And for the tweet thing that I've been using, I've got my head is here, so I need to indicate to tweet, 64 00:05:30,010 --> 00:05:35,170 which is the recipient that I'll be sending a chasten body content type. 65 00:05:35,680 --> 00:05:38,200 So I'm doing that with the headers variable. 66 00:05:38,200 --> 00:05:42,970 I'm going to be using beheaders variable down here when I make my post request. 67 00:05:44,350 --> 00:05:45,460 So let's continue. 68 00:05:45,470 --> 00:05:47,070 I've got the URL for the tweet. 69 00:05:47,710 --> 00:05:55,960 So this is the base Eurail plus the thing name which I'm extracting from the tweets credentials file 70 00:05:57,220 --> 00:06:03,130 and I've got the exact same do connect method as in the previous lecture's example. 71 00:06:03,780 --> 00:06:10,890 I create the W lan object call the do connect method to make the connection happen. 72 00:06:11,710 --> 00:06:18,000 So as long as I have a connection, then print out the address, the acquired IP address. 73 00:06:18,640 --> 00:06:25,510 Now in this example, I chose to use a timer instead of an infinite loop, and I've set the timer to 74 00:06:25,510 --> 00:06:30,860 send out a new tweet every five seconds or 5000 milliseconds. 75 00:06:31,360 --> 00:06:38,840 So when the five seconds expire, the hardware timer is going to call the post to tweet Aisa, which 76 00:06:38,850 --> 00:06:41,460 jumps the execution of the program up here. 77 00:06:42,130 --> 00:06:47,050 So first get a couple of random values for the temperature and humidity. 78 00:06:47,530 --> 00:06:55,890 I create my chasing object like this, so temp is a random temperature and humidity hum. 79 00:06:56,380 --> 00:06:57,820 It's the random humidity. 80 00:06:58,210 --> 00:07:01,420 Then in line eighty nine I make my post request. 81 00:07:01,630 --> 00:07:09,220 There's the post verb, I'm passing on the URL variable and then the head is viable earlier. 82 00:07:09,760 --> 00:07:11,680 And of course the data and the data. 83 00:07:11,710 --> 00:07:14,020 Remember that this is a chasten object. 84 00:07:14,290 --> 00:07:21,670 I'm going to use a dump's command to create the chasten object out of the data variable. 85 00:07:24,260 --> 00:07:33,590 Next in line 90, I get the response from the widowed IYO and amusingly, load's method of the chasten 86 00:07:33,590 --> 00:07:41,230 module to convert that into a valid JSON document, which I stored in the tweet back viable. 87 00:07:41,780 --> 00:07:50,780 And after that, I'm using these constructs here to extract the individual bits of information from 88 00:07:50,780 --> 00:07:55,720 the adjacent object that we thought IO has returned in the first line. 89 00:07:55,730 --> 00:08:02,000 Ninety one, I just print out the entire object, but after that 1992, 92 and onwards, I'm a bit more 90 00:08:02,000 --> 00:08:02,720 selective. 91 00:08:02,720 --> 00:08:07,720 And in this case, for example, I am grabbing the variable stored. 92 00:08:07,870 --> 00:08:13,040 I just go back to the response point here this so you can see the structure. 93 00:08:13,280 --> 00:08:20,900 I'm looking for the width value right here, which itself contains an adjacent document embedded inside 94 00:08:20,900 --> 00:08:22,430 that embedded chasten document. 95 00:08:22,430 --> 00:08:27,800 I'm looking for the created key, which is right here, so I'm putting that as well. 96 00:08:29,020 --> 00:08:35,050 And then this whole construct together, the two kids, right after one after the other, gives me the 97 00:08:36,130 --> 00:08:40,390 time and date when this tweet was captured by tweet what? 98 00:08:40,410 --> 00:08:43,410 I am doing the same thing with a few others. 99 00:08:43,450 --> 00:08:47,170 Let's have a look at, for example, the the humidity. 100 00:08:47,170 --> 00:08:52,930 If you want to get the humidity value from the response body, which you can see right here, the name 101 00:08:52,930 --> 00:08:58,590 of its key is Hum, which is contained inside content, which is contained inside with. 102 00:08:58,930 --> 00:09:04,300 So that's why you see this construct here in line 96. 103 00:09:06,190 --> 00:09:12,760 All right, so let's try it out and see if it actually works, this tap indicates that the script right 104 00:09:12,760 --> 00:09:16,640 now is on my file system, which is OK. 105 00:09:16,900 --> 00:09:19,540 It will still work when I it to the hospital, too. 106 00:09:19,780 --> 00:09:26,160 And I've got my credentials file already uploaded to the two to flash file system. 107 00:09:26,560 --> 00:09:28,420 I'm just going to click on run script. 108 00:09:30,140 --> 00:09:31,430 First time didn't work. 109 00:09:32,650 --> 00:09:33,850 So they can do their work. 110 00:09:33,910 --> 00:09:34,550 Let's try again. 111 00:09:34,640 --> 00:09:43,790 OK, third time did to why there is a failure in the first couple of attempts, but it's OK, right? 112 00:09:43,810 --> 00:09:45,610 So the third one worked. 113 00:09:45,910 --> 00:09:48,490 It can see that every five seconds. 114 00:09:48,820 --> 00:09:53,830 I'm getting a tweet posted to Twitter IIO. 115 00:09:53,830 --> 00:09:56,410 The response comes back and. 116 00:09:58,620 --> 00:10:06,670 It provides me with a response object in its entirety and then decomposed individual components of that 117 00:10:06,930 --> 00:10:07,580 response. 118 00:10:08,220 --> 00:10:09,990 So let's see. 119 00:10:11,160 --> 00:10:20,210 I'm just going to have a look at the guest request here on the tweet board, I'll play page. 120 00:10:20,580 --> 00:10:21,720 I already have the U. 121 00:10:21,720 --> 00:10:25,770 Python thing named inside the field. 122 00:10:26,010 --> 00:10:27,540 You're going to click on Try Out. 123 00:10:29,220 --> 00:10:32,000 And get the latest values, all right. 124 00:10:32,040 --> 00:10:34,080 You can see that again. 125 00:10:36,010 --> 00:10:39,220 Twenty three, twenty eight to 20 to see if this matches. 126 00:10:42,480 --> 00:10:46,560 Thirty four to twenty nine, he killed thirty four, twenty nine. 127 00:10:46,650 --> 00:10:47,970 Right, we are right here. 128 00:10:51,320 --> 00:10:53,060 Let's do one more try out. 129 00:10:54,180 --> 00:11:03,900 Sixteen forty, which are sick and lost values posted so you can see that whatever my device is posting 130 00:11:04,470 --> 00:11:05,460 anyone else. 131 00:11:06,400 --> 00:11:08,470 There is doing a get request. 132 00:11:09,820 --> 00:11:13,600 To this year will be able to get some I'm just going to go to a new. 133 00:11:15,000 --> 00:11:25,890 Tab posted in there and you can see that this is a raw value of the raw wheat that my be 32 has just 134 00:11:25,890 --> 00:11:26,550 posted. 135 00:11:26,670 --> 00:11:30,690 I can just hit refresh and get the very latest each time. 136 00:11:35,650 --> 00:11:36,300 Still unknown. 137 00:11:41,940 --> 00:11:42,270 Become. 138 00:11:43,320 --> 00:11:51,210 All right, so this works and concludes system illustration, just in summary, can say that we don't 139 00:11:51,230 --> 00:11:57,580 improvise a very simple way to set to connect devices together via a Twitter like mechanism. 140 00:11:58,050 --> 00:12:05,730 All you need to do to do one, get request to receive data or one post request to send data from your 141 00:12:05,760 --> 00:12:06,870 ISP three, two. 142 00:12:07,080 --> 00:12:09,990 And you've got these two devices connected. 143 00:12:11,020 --> 00:12:19,180 OK, now let's move on to the next lecture where I'll show you how to use a post request to send a notification 144 00:12:19,180 --> 00:12:20,710 email via this.