WEBVTT 00:00.840 --> 00:02.880 -: In the last section, we pushed off our project 00:02.880 --> 00:05.880 to Travis CI, or more precisely GitHub. 00:05.880 --> 00:08.970 Travis CI picked up the project and started building it. 00:08.970 --> 00:10.530 So my project finished building, 00:10.530 --> 00:12.030 all the tests ran successfully, 00:12.030 --> 00:14.250 and you can see down here it says preparing deploy, 00:14.250 --> 00:17.310 and then deploying application, and then eventually done. 00:17.310 --> 00:20.040 If you now very quickly go over to your Docker dashboard 00:20.040 --> 00:21.480 and refresh the page, 00:21.480 --> 00:23.040 really important, make sure you do the refresh 00:23.040 --> 00:24.570 because it won't always kick in 00:24.570 --> 00:26.340 the updates here automatically. 00:26.340 --> 00:27.667 You might see these spinners that say, 00:27.667 --> 00:29.970 "Oh hey, we're doing a deploy for you." 00:29.970 --> 00:31.200 So the reason that I'm showing you 00:31.200 --> 00:32.700 this kind of spinner right here 00:32.700 --> 00:35.040 before the deploy actually finishes up, 00:35.040 --> 00:36.540 is that when this finishes 00:36.540 --> 00:39.510 there's actually gonna be a little bit of an issue. 00:39.510 --> 00:42.300 We're gonna see that after deploy completes successfully 00:42.300 --> 00:44.520 if we try navigating to our URL, 00:44.520 --> 00:46.650 the page is just not going to load up. 00:46.650 --> 00:48.700 So let me tell you about what's going on. 00:50.580 --> 00:54.090 If you recall, every time that we've ran a web server 00:54.090 --> 00:55.290 inside of a Docker container, 00:55.290 --> 00:58.260 we've had to do something like docker run -p, 00:58.260 --> 01:00.780 and then we did that port mapping 01:00.780 --> 01:02.190 and then specified the container 01:02.190 --> 01:03.900 or whatever it might have been. 01:03.900 --> 01:05.580 So the port mapping right there is done 01:05.580 --> 01:09.390 because by default no port inside of the container 01:09.390 --> 01:11.220 gets exposed to the outside world, 01:11.220 --> 01:14.490 we have to very directly set up that port mapping ourselves. 01:14.490 --> 01:15.930 Now you might notice that everything 01:15.930 --> 01:17.970 that we just did with Elastic Beanstalk, 01:17.970 --> 01:21.510 at no point in time did any of this port mapping occur. 01:21.510 --> 01:23.310 So it's a step that we just kind of 01:23.310 --> 01:25.323 completely neglected to take care of. 01:26.250 --> 01:28.200 The reason that we didn't take care of it right away 01:28.200 --> 01:30.510 is that if you went through all the documentation 01:30.510 --> 01:32.790 on Elastic Beanstalk around Docker, 01:32.790 --> 01:34.620 well they're gonna be, they're not gonna quite 01:34.620 --> 01:36.480 throw this little tip out there at you. 01:36.480 --> 01:37.507 You know, they're not gonna really say, 01:37.507 --> 01:39.570 "Oh yeah, you need to expose the port", 01:39.570 --> 01:41.970 because when we expose the port on Elastic Beanstalk 01:41.970 --> 01:44.070 the process is just a little bit different 01:44.070 --> 01:46.980 than the command line that we've been doing so far. 01:46.980 --> 01:49.350 So to expose a port with Elastic Beanstalk, 01:49.350 --> 01:50.253 here's what we do. 01:51.840 --> 01:53.520 We're gonna find our dockerfile 01:53.520 --> 01:55.740 that is used for production deployments, 01:55.740 --> 01:59.130 and then inside of here, right after the "FROM nginx", 01:59.130 --> 02:02.763 we're going to say EXPOSE 80, like so. 02:04.080 --> 02:05.940 The EXPOSE instruction is something 02:05.940 --> 02:07.950 that we have not used before. 02:07.950 --> 02:09.510 In a development environment, 02:09.510 --> 02:11.520 and actually in most environments, 02:11.520 --> 02:14.310 the EXPOSE instruction is really supposed to be 02:14.310 --> 02:17.190 communication to you and I as developers. 02:17.190 --> 02:18.690 This is really something for you and I 02:18.690 --> 02:21.697 to read inside of a dockerfile and understand, 02:21.697 --> 02:23.797 "Oh, this container probably needs 02:23.797 --> 02:26.400 "to get a port mapped to Port 80." 02:26.400 --> 02:28.260 So by default on our machines, 02:28.260 --> 02:30.090 like your laptop and my laptop, 02:30.090 --> 02:31.770 just putting in this instruction 02:31.770 --> 02:35.370 does absolutely nothing for us automatically. 02:35.370 --> 02:39.210 Now, AWS Elastic Beanstalk is just a little bit different. 02:39.210 --> 02:42.570 Elastic Beanstalk, when it starts up your Docker container, 02:42.570 --> 02:44.310 it's gonna look at this dockerfile 02:44.310 --> 02:47.463 and it's gonna look for the EXPOSE instruction, 02:48.390 --> 02:50.610 and then whatever port you list in there 02:50.610 --> 02:52.320 is what Elastic Beanstalk 02:52.320 --> 02:55.710 is going to map directly, automatically. 02:55.710 --> 02:57.060 So again, for you and me, 02:57.060 --> 02:59.640 just putting EXPOSE in here does automatically nothing. 02:59.640 --> 03:02.400 Elastic Beanstalk is different in that regard, 03:02.400 --> 03:04.620 it's going to look at this EXPOSE instruction 03:04.620 --> 03:06.090 and use that as the port 03:06.090 --> 03:09.000 that gets mapped for incoming traffic. 03:09.000 --> 03:10.680 So I'm gonna save this, 03:10.680 --> 03:13.140 and again I wanted you to see this ahead of time 03:13.140 --> 03:14.910 because I didn't want you to like, 03:14.910 --> 03:16.260 and as a matter of fact you'll see right here 03:16.260 --> 03:17.994 it says degraded. 03:17.994 --> 03:19.027 Chances are it'll say something like, 03:19.027 --> 03:21.307 "Sorry, but I wasn't able to actually start up 03:21.307 --> 03:22.170 "or anything like that." 03:22.170 --> 03:23.570 Probably somewhere in there. 03:24.420 --> 03:25.920 Well, somewhere in there, it'll be there 03:25.920 --> 03:26.940 but you get the idea. 03:26.940 --> 03:28.170 It definitely is not working 03:28.170 --> 03:29.790 quite the way we expect right now. 03:29.790 --> 03:32.190 So we're going to make that change, 03:32.190 --> 03:33.570 I got the EXPOSE 80 there. 03:33.570 --> 03:34.800 I'm gonna save the file. 03:34.800 --> 03:36.510 We're gonna do another git commit, 03:36.510 --> 03:40.590 another push up to master and let everything deploy again. 03:40.590 --> 03:43.770 So back in my terminal, I'll do a git add, 03:43.770 --> 03:47.730 I'll do a git commit, I'll say added EXPOSE 80, 03:47.730 --> 03:50.280 and I'll do a git push origin master, 03:50.280 --> 03:51.270 and we're gonna let this thing 03:51.270 --> 03:53.280 redeploy itself all over again. 03:53.280 --> 03:56.130 So another quick break and I'll see you in just a minute.