WEBVTT 1 00:00.000 --> 00:04.990 Alright friends, let's now talk about something known as an API. You may have 2 00:04.990 --> 00:05.520 heard of this 3 00:05.520 --> 00:09.520 term many times before and you are just a little bit confused as to what it's 4 00:09.520 --> 00:10.320 all about. 5 00:10.320 --> 00:14.730 It can be a little bit obscure and a little bit esoteric the first time you 6 00:14.730 --> 00:15.440 hear it. So let's try 7 00:15.440 --> 00:20.400 to demystify what an earth this is all about. The first thing to state is that 8 00:20.400 --> 00:21.600 an API is just an 9 00:21.600 --> 00:26.680 acronym for an application programming interface. Okay great, class is over, we 10 00:26.680 --> 00:27.360 now know everything 11 00:27.360 --> 00:33.470 about APIs, let's just go home and drink coffee. Well obviously this here doesn WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 11 00:27.360 --> 00:33.470 about APIs, let's just go home and drink coffee. Well obviously this here doesn 12 00:33.470 --> 00:34.240 't give you much 13 00:34.240 --> 00:38.940 more information just by simply knowing what each letter represents but the 14 00:38.940 --> 00:39.920 name here actually 15 00:39.920 --> 00:43.690 is pretty descriptive, believe or not. It really is a way for us to interface 16 00:43.690 --> 00:44.560 or interact with 17 00:44.560 --> 00:48.560 particular applications, particularly in a programmatic manner. So let me show 18 00:48.560 --> 00:49.360 you what I mean. 19 00:49.360 --> 00:52.320 Let's imagine we've got a little application over here, we'll just call this 20 00:52.320 --> 00:53.280 app one okay 21 00:53.280 --> 00:56.860 and all the way over here we're going to have application to a completely 22 00:56.860 --> 00:58.080 separate app. So I don't 23 00:58.080 --> 01:02.040 know let's maybe say this application is some type of chatting application, WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 23 00:58.080 --> 01:02.040 know let's maybe say this application is some type of chatting application, 24 01:02.040 --> 01:02.800 maybe something like 25 01:02.800 --> 01:06.870 say Slack or Cisco WebEx that type of thing, basically a place whereby you can 26 01:06.870 --> 01:07.680 type particular 27 01:07.680 --> 01:11.560 messages to your friends chatting communicate have all that type of fun. Now 28 01:11.560 --> 01:13.520 over here let's imagine 29 01:13.520 --> 01:17.250 that this is some type of weather application whereby it's going to gather 30 01:17.250 --> 01:18.800 information and statistics 31 01:18.800 --> 01:23.100 based on particular locations. So if you use this app you can give it your GPS 32 01:23.100 --> 01:24.080 coordinates, find 33 01:24.080 --> 01:27.200 it your location and then determine what the weather should be for the next 34 01:27.200 --> 01:28.320 week okay so completely 35 01:28.320 --> 01:31.760 different applications and who knows behind the scenes they may be written in WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 35 01:28.320 --> 01:31.760 different applications and who knows behind the scenes they may be written in 36 01:31.760 --> 01:32.400 completely different 37 01:32.400 --> 01:36.140 programming languages. Let's just imagine that this one here is written in the 38 01:36.140 --> 01:37.040 Python programming 39 01:37.040 --> 01:41.920 language whereas this one here is written in the Go programming language. So 40 01:41.920 --> 01:43.600 the question I have 41 01:43.600 --> 01:47.460 is what actually happens if these two applications want to be able to 42 01:47.460 --> 01:49.360 communicate with one another. 43 01:49.360 --> 01:54.000 So say for example we wanted to have some type of automated service whereby in 44 01:54.000 --> 01:54.880 the chatting 45 01:54.880 --> 01:58.990 application maybe we've got a dedicated room for the weather and all this 46 01:58.990 --> 02:00.400 application does is WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 46 01:58.990 --> 02:00.400 application does is 47 02:00.400 --> 02:05.410 automatically reaches out to the weather application and ingest the data and 48 02:05.410 --> 02:06.880 populate it within 49 02:06.880 --> 02:10.080 the actual application right here okay. Can a similar to how your cell phone 50 02:10.080 --> 02:10.640 might work you 51 02:10.640 --> 02:13.140 may open up your application and suddenly you see that you're getting 52 02:13.140 --> 02:14.160 information about weather 53 02:14.160 --> 02:17.700 updates on the home screen. This information could be very well coming from an 54 02:17.700 --> 02:18.560 external source 55 02:18.560 --> 02:22.200 and external app completely. So we've got two different applications two 56 02:22.200 --> 02:23.520 different code bases 57 02:23.520 --> 02:28.170 entirely but they want to communicate. Now the way they're actually going to 58 02:28.170 --> 02:29.440 communicate is via 59 02:29.440 --> 02:34.500 the use of APIs. So really at its core what does an API actually give you for WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 59 02:29.440 --> 02:34.500 the use of APIs. So really at its core what does an API actually give you for 60 02:34.500 --> 02:35.520 real? Quite simply 61 02:35.520 --> 02:40.080 it's a way for you to interact with your application in these simplified manner 62 02:40.080 --> 02:40.720 without having to 63 02:40.720 --> 02:45.290 care about all the back end details how the application is actually programmed 64 02:45.290 --> 02:46.000 and all the wonderful 65 02:46.000 --> 02:50.320 things going on the background. It's just your door to using that application 66 02:50.320 --> 02:51.120 to get information 67 02:51.120 --> 02:55.280 from it to pass information to it. Pretty much the API here is going to be the 68 02:55.280 --> 02:56.400 doorway for you. 69 02:56.400 --> 03:00.400 Let me help you understand this via a well known analogy okay. This is the way WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 69 02:56.400 --> 03:00.400 Let me help you understand this via a well known analogy okay. This is the way 70 03:00.400 --> 03:01.040 that I learned about 71 03:01.040 --> 03:05.690 APIs and when I heard it it really did help the whole concept. Click for me. So 72 03:05.690 --> 03:06.480 let's imagine you want 73 03:06.480 --> 03:09.640 to go to a restaurant okay. So let me just show you my good skills of drawing 74 03:09.640 --> 03:10.640 here as the restaurant 75 03:10.640 --> 03:15.470 right here. Now in here this can be the kitchen whereby all of the chefs are 76 03:15.470 --> 03:16.400 working. Okay so you 77 03:16.400 --> 03:20.590 get your chefs here you've got all your pots on your stoves on, frying pans are 78 03:20.590 --> 03:21.440 going, people are 79 03:21.440 --> 03:25.980 cutting vegetables that type of thing. Now you as a customer who actually wants 80 03:25.980 --> 03:27.040 to will enjoy the 81 03:27.040 --> 03:31.590 services offered up via this restaurant at either food they're serving you walk WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 81 03:27.040 --> 03:31.590 services offered up via this restaurant at either food they're serving you walk 82 03:31.590 --> 03:32.800 in and you sit down 83 03:32.800 --> 03:37.230 at a table. Now think about how do you actually get the food that you want. Do 84 03:37.230 --> 03:38.880 you have to understand 85 03:38.880 --> 03:42.900 how many chefs in the kitchen? Do you have to understand how many knives there 86 03:42.900 --> 03:44.400 are? How many pots 87 03:44.400 --> 03:48.690 and pans there are? You do not care about any of this stuff whatsoever. The 88 03:48.690 --> 03:50.000 only thing that you do in 89 03:50.000 --> 03:54.650 order to get the services you want is that you just talk directly to the waiter 90 03:54.650 --> 03:55.680 okay. So the waiter 91 03:55.680 --> 04:00.210 might come here give you a list of all the available services via a menu and WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 91 03:55.680 --> 04:00.210 might come here give you a list of all the available services via a menu and 92 04:00.210 --> 04:01.440 you just go hey Mr. 93 04:01.440 --> 04:05.050 waiter I would just like to order and then give your order I would like to have 94 04:05.050 --> 04:06.000 a pizza that type of 95 04:06.000 --> 04:10.070 thing okay. So this is your way of interacting with all of this magic in the 96 04:10.070 --> 04:11.040 background that you 97 04:11.040 --> 04:15.330 really don't have to care about. Now the waiter effectively takes your request 98 04:15.330 --> 04:16.400 and release it back 99 04:16.400 --> 04:20.420 to the staff in the kitchen and now all of this fantastic teamwork kicks in 100 04:20.420 --> 04:21.680 your food has begun to 101 04:21.680 --> 04:25.460 be prepared. Now here's the thing let's maybe say 15 minutes of past and your 102 04:25.460 --> 04:26.640 food is still not there. 103 04:26.640 --> 04:32.140 If you want to get information i.e. a query about the state of your request but WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 103 04:26.640 --> 04:32.140 If you want to get information i.e. a query about the state of your request but 104 04:32.140 --> 04:33.200 once again you just 105 04:33.200 --> 04:36.630 directly ask the waiter to really that information and the waiter can go and 106 04:36.630 --> 04:38.240 get an update and say hey 107 04:38.240 --> 04:41.100 how long is this food going to be and then the waiter can find out you know it 108 04:41.100 --> 04:42.080 's going to be another 109 04:42.080 --> 04:45.700 three minutes and the waiter can therefore tell you this information there'll 110 04:45.700 --> 04:46.640 be three more minutes 111 04:46.640 --> 04:50.940 and now you have the latest update of the information. Now this has got nothing 112 04:50.940 --> 04:52.160 to do with coding or 113 04:52.160 --> 04:56.120 automation but this is really close to how API's operates. Imagine you have a 114 04:56.120 --> 04:57.040 web server that is 115 04:57.040 --> 05:00.920 offering services this is like what you're getting in the kitchen if you want WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 115 04:57.040 --> 05:00.920 offering services this is like what you're getting in the kitchen if you want 116 05:00.920 --> 05:02.240 to consume and enjoy 117 05:02.240 --> 05:05.320 whatever the service happens to be offering then the way you get that 118 05:05.320 --> 05:07.280 information is by communicating via 119 05:07.280 --> 05:11.850 this middleman ultimately simplifies the process. From your point of view you 120 05:11.850 --> 05:12.800 just simply ask for 121 05:12.800 --> 05:16.830 what you want and then suddenly due to the API or the waiter all of this 122 05:16.830 --> 05:18.320 complexity happens in the 123 05:18.320 --> 05:22.240 background and you're served up exactly what you ask for. Same kind of thing 124 05:22.240 --> 05:23.200 like if you happen to 125 05:23.200 --> 05:26.150 have a vending machine okay you walk out in your lunch break here is the v 126 05:26.150 --> 05:27.520 ending machine once again my 127 05:27.520 --> 05:32.690 art is absolutely awesome and let's maybe say we've got some you know some WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 127 05:27.520 --> 05:32.690 art is absolutely awesome and let's maybe say we've got some you know some 128 05:32.690 --> 05:34.320 stuff right here. So what 129 05:34.320 --> 05:38.000 do you do you walk up on your lunch break you decide you want to have maybe a 130 05:38.000 --> 05:38.960 bar of chocolate. 131 05:38.960 --> 05:42.770 Now what do you actually do notice that actually is a little menu here like a 132 05:42.770 --> 05:43.760 little keypad type 133 05:43.760 --> 05:47.060 thing and all you do is you walk up to the keypad and this is a part you 134 05:47.060 --> 05:48.640 interact with okay so then 135 05:48.640 --> 05:52.860 maybe you type in something like say a five and then maybe some type of robotic 136 05:52.860 --> 05:53.760 arm slides along 137 05:53.760 --> 05:58.240 here goes up and fetches the item that you're doing then pulls all the way back 138 05:58.240 --> 05:58.800 down and there 139 05:58.800 --> 06:02.250 might be a little slot down here and your chocolate bar is released whereby you WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 139 05:58.800 --> 06:02.250 might be a little slot down here and your chocolate bar is released whereby you 140 06:02.250 --> 06:03.440 can stick your hand in 141 06:03.440 --> 06:07.190 and pull it out. So once again this is an example of you're not having to care 142 06:07.190 --> 06:08.720 about the details 143 06:08.720 --> 06:12.160 of all the robotics happening in the background you don't care about the 144 06:12.160 --> 06:13.440 programming logic all you 145 06:13.440 --> 06:18.710 effectively do is interact with this via this simplified entry point this is 146 06:18.710 --> 06:20.000 once again kind of 147 06:20.000 --> 06:24.160 an analogy to what we're talking about with APIs you have a simplified entry 148 06:24.160 --> 06:25.200 points and that's really 149 06:25.200 --> 06:29.560 all you have to care about when getting the services that you're after. So let 150 06:29.560 --> 06:30.720 me actually show you WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 150 06:29.560 --> 06:30.720 me actually show you 151 06:30.720 --> 06:35.650 an example of using an API just so that you can see that they're really not 152 06:35.650 --> 06:36.720 that complex to 153 06:36.720 --> 06:41.500 use in fact I am willing to bed you have used this type of API before let's 154 06:41.500 --> 06:42.480 imagine that studying 155 06:42.480 --> 06:46.170 Cisco networking is getting you a little bit stressed out and you want to go to 156 06:46.170 --> 06:47.200 a vacation so what 157 06:47.200 --> 06:51.770 do you do you go to a website like this Expedia in this case right here what I 158 06:51.770 --> 06:52.960 'm going to do is to 159 06:52.960 --> 06:56.460 choose my location so let's go down here let's maybe say I'm going to let's say 160 06:56.460 --> 06:57.680 the Bahamas okay 161 06:57.680 --> 07:00.870 and then I can specify when it is I want to go let's go from the 9th of WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 161 06:57.680 --> 07:00.870 and then I can specify when it is I want to go let's go from the 9th of 162 07:00.870 --> 07:02.480 September to the 15th we'll 163 07:02.480 --> 07:06.760 say done now right now if I just run a search what is going to happen here as 164 07:06.760 --> 07:07.920 you can see as a whole 165 07:07.920 --> 07:11.370 bunch of queries are being made and we get the response already now right here 166 07:11.370 --> 07:12.320 why I actually did 167 07:12.320 --> 07:17.090 was ultimately kick off a whole bunch of API requests quite simply I specified 168 07:17.090 --> 07:17.920 very particular 169 07:17.920 --> 07:22.900 details that I wanted okay now Expedia doesn't just have a database with all of 170 07:22.900 --> 07:24.160 the potential things 171 07:24.160 --> 07:28.500 that you can effectively ask for what they do is they take this information 172 07:28.500 --> 07:29.600 okay and they bundle 173 07:29.600 --> 07:34.190 up programmatically and they begin firing it off to the APIs of all of these WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 173 07:29.600 --> 07:34.190 up programmatically and they begin firing it off to the APIs of all of these 174 07:34.190 --> 07:35.760 different providers so 175 07:35.760 --> 07:39.940 we might be talking to like British Airways or to Delta Airlines that type of 176 07:39.940 --> 07:40.800 thing getting 177 07:40.800 --> 07:45.350 information from them directly from their systems to actually determine you 178 07:45.350 --> 07:46.480 know what flight times 179 07:46.480 --> 07:50.110 are available correspond with this particular request and we are essentially 180 07:50.110 --> 07:51.120 aggregating them 181 07:51.120 --> 07:54.640 and presenting them here all in one place from me as a user to look at and 182 07:54.640 --> 07:55.760 examine and again it's 183 07:55.760 --> 07:58.540 not just flight she could be querying you could be querying a whole bunch of 184 07:58.540 --> 07:59.600 different hotels in that 185 07:59.600 --> 08:03.750 particular area like a Mario or a Hilton that type of thing quite simply we are WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 185 07:59.600 --> 08:03.750 particular area like a Mario or a Hilton that type of thing quite simply we are 186 08:03.750 --> 08:05.360 using Expedia to go 187 08:05.360 --> 08:09.590 and talk to all of the different providers so Expedia on her behalf is actually 188 08:09.590 --> 08:10.800 making API calls 189 08:10.800 --> 08:15.330 with a talking to the British Airways API they're talking to the Virgin 190 08:15.330 --> 08:17.200 Airlines API that type of thing 191 08:17.200 --> 08:21.000 gathering all the information and seeing which data is relevant for my 192 08:21.000 --> 08:22.400 particular request now in a 193 08:22.400 --> 08:26.040 similar way let's say I go to book a particular deal once again I give the 194 08:26.040 --> 08:27.760 information to Expedia 195 08:27.760 --> 08:32.380 and then Expedia sends off these requests to these API endpoints to ensure that WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 195 08:27.760 --> 08:32.380 and then Expedia sends off these requests to these API endpoints to ensure that 196 08:32.380 --> 08:33.360 I'm actually booking 197 08:33.360 --> 08:37.000 with the hotel and the hotel get my information and ensuring that I'm actually 198 08:37.000 --> 08:38.000 booking with the flight 199 08:38.000 --> 08:41.820 provider and ensuring they get my information and again you could do this on 200 08:41.820 --> 08:42.880 your phone you could open 201 08:42.880 --> 08:46.720 up the Expedia application which is one app and if it wants to have to talk to 202 08:46.720 --> 08:47.840 the British Airways 203 08:47.840 --> 08:52.250 application all the Virgin application that type of thing these requests are 204 08:52.250 --> 08:53.280 all made to each 205 08:53.280 --> 08:57.660 applications API and then ultimately sent back so this really is the basic 206 08:57.660 --> 08:59.120 concept behind APIs it's 207 08:59.120 --> 09:02.600 going to facilitate communication programmatically between applications in a WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 207 08:59.120 --> 09:02.600 going to facilitate communication programmatically between applications in a 208 09:02.600 --> 09:04.080 nice simplified manner 209 09:04.080 --> 09:07.130 now that we have that part under a belt the next thing that I want to talk 210 09:07.130 --> 09:08.720 about is a very particular 211 09:08.720 --> 09:13.060 type of API and this one is known as your rest API let's talk about that in the 212 09:13.060 --> 09:14.560 very next video