WEBVTT 00:00.981 --> 00:01.814 -: In the last section, we put 00:01.814 --> 00:03.360 together all the source code that we're gonna need 00:03.360 --> 00:06.270 for right now for the worker project. 00:06.270 --> 00:08.520 Again, the worker is what's going to watch Redis. 00:08.520 --> 00:11.430 Anytime that we get a new index inserted into Redis 00:11.430 --> 00:13.140 the worker will automatically pull the value 00:13.140 --> 00:15.780 out and calculate the appropriate fibonacci value for it 00:15.780 --> 00:19.020 and then insert that value back into Redis. 00:19.020 --> 00:21.560 We're now gonna start putting together the code 00:21.560 --> 00:22.470 for the express server. 00:22.470 --> 00:24.720 As a quick reminder, if you don't want to go through any 00:24.720 --> 00:28.170 of this JavaScript specific setup, you can always move on 00:28.170 --> 00:30.180 to the next section and you'll find all the source 00:30.180 --> 00:32.580 code that we're writing inside that section. 00:32.580 --> 00:34.530 So all you have to do is download the file there 00:34.530 --> 00:36.660 and unzip it into your project. 00:36.660 --> 00:38.820 I'm only walking you through all the source code right now 00:38.820 --> 00:39.960 in case you're kind of curious 00:39.960 --> 00:42.960 about how to write a JavaScript application that makes use 00:42.960 --> 00:44.850 of all these different pieces. 00:44.850 --> 00:47.010 So let's get started on the express server 00:47.010 --> 00:48.330 that's going to serve as the sort 00:48.330 --> 00:50.190 of API layer that communicates 00:50.190 --> 00:53.220 with Redis and Postgres and communicates information 00:53.220 --> 00:55.383 over to a running react application. 00:57.090 --> 00:58.710 Back inside my code editor 00:58.710 --> 01:01.440 we were just working inside that worker directory. 01:01.440 --> 01:03.450 I'm now gonna make a second directory 01:03.450 --> 01:05.580 that I'm going to call server. 01:05.580 --> 01:08.580 And this thing is gonna house all the code for our server, 01:08.580 --> 01:11.970 the express server, that's gonna function as the API. 01:11.970 --> 01:13.500 Now, quick note here, please make sure 01:13.500 --> 01:15.300 that you make the server directory next 01:15.300 --> 01:17.880 to or as a sibling to the worker folder. 01:17.880 --> 01:21.090 You do not want to place the folder inside 01:21.090 --> 01:23.310 of the worker process. Don't want that. 01:23.310 --> 01:27.390 So it needs to be outside in a separate sibling folder. 01:27.390 --> 01:28.860 Now inside of here, we'll get started 01:28.860 --> 01:31.173 by making a package.json on file. 01:32.190 --> 01:34.170 We're gonna have a couple of different dependencies 01:34.170 --> 01:36.240 and a couple of different scripts as well. 01:36.240 --> 01:38.430 We'll first lift off or list off, excuse me 01:38.430 --> 01:41.910 the different dependencies that our project is gonna have. 01:41.910 --> 01:45.090 For dependencies, we're gonna get express at version 01:45.090 --> 01:46.310 4.16.3. 01:48.900 --> 01:52.160 We're going to get a Postgres client at 7.4.3. 01:54.780 --> 01:59.780 We're going to get a Redis client at 2.8.0. 02:01.350 --> 02:04.563 We'll get a Cores installation at 2.8.4. 02:07.020 --> 02:09.660 And we'll get Nodemon as well for development purposes 02:09.660 --> 02:12.810 at 1.18.3 like so. 02:12.810 --> 02:15.480 And again, we'll talk about why we are installing Nodemon 02:15.480 --> 02:18.513 as we start to put together the Docker side of this project. 02:19.770 --> 02:21.600 Now next to the dependencies, I'm gonna also 02:21.600 --> 02:23.223 define a script section. 02:26.130 --> 02:28.110 Very similar to the worker process. 02:28.110 --> 02:30.240 We're going to have a development script or a dev 02:30.240 --> 02:31.893 script that runs Nodemon. 02:34.020 --> 02:35.970 And then we will also have a start script 02:35.970 --> 02:38.433 for node index.js. 02:39.900 --> 02:41.700 All right, as usual, please double check 02:41.700 --> 02:43.920 make sure that you've got your commas after each one 02:43.920 --> 02:45.330 of these lines. 02:45.330 --> 02:47.730 And make sure you've got double quotes everywhere inside 02:47.730 --> 02:48.563 of here. 02:48.563 --> 02:49.860 Need double quotes everywhere. 02:50.850 --> 02:52.590 Once we've got the package.json file 02:52.590 --> 02:55.290 all put together, I'll delete this, or excuse me 02:55.290 --> 02:58.140 close the file, not delete it, my mistake. 02:58.140 --> 02:59.880 And then inside the server directory 02:59.880 --> 03:04.560 we're gonna make another file called keys.js. 03:04.560 --> 03:08.310 And just like before this file is going to house some 03:08.310 --> 03:09.690 of the different variables that we're going to 03:09.690 --> 03:12.180 need to connect to the running instance 03:12.180 --> 03:13.800 of Redis and the running instance 03:13.800 --> 03:16.650 of Postgres that will be associated with our application. 03:18.180 --> 03:20.490 Inside of the keys.js file 03:20.490 --> 03:23.100 I'll say module.exports 03:23.100 --> 03:24.960 and then inside of here, we're gonna have a pretty 03:24.960 --> 03:27.900 good different number of pieces of configuration. 03:27.900 --> 03:30.660 So please again, double check your typing in here 03:30.660 --> 03:33.060 because we're gonna do a lot of typing. 03:33.060 --> 03:35.820 I'll first do a Redis host that's gonna come 03:35.820 --> 03:40.820 from the environment variable process.env.Redis host. 03:43.560 --> 03:44.710 We'll get a Redis port. 03:49.470 --> 03:52.500 We will get a PG user. 03:52.500 --> 03:56.130 This is the Postgres user that we're going to log in as 03:56.130 --> 03:59.373 from process.env.pg user. 04:00.270 --> 04:01.623 We'll do a PG host. 04:06.690 --> 04:08.880 We'll do a PG database. 04:08.880 --> 04:11.910 This is going to be the name of the database inside 04:11.910 --> 04:14.060 of Postgres that we're going to connect to. 04:15.810 --> 04:17.373 PG database. 04:18.570 --> 04:20.613 We'll get a PG password. 04:21.660 --> 04:24.750 As you might guess, this is the password to the database 04:24.750 --> 04:26.850 which we're going to have to define at some point. 04:26.850 --> 04:28.503 So PG password. 04:29.910 --> 04:31.653 We'll get a PG port. 04:36.300 --> 04:37.590 Like so as well. 04:37.590 --> 04:42.590 So we should see 1, 2, 3, 4, 5, 6, 7 entries inside of here. 04:43.080 --> 04:44.880 Now I gotta ask you at this point again 04:44.880 --> 04:47.160 please make sure that all of these environment 04:47.160 --> 04:48.920 variable names are capitalized. 04:48.920 --> 04:51.420 So you should see capital PG user, capital 04:51.420 --> 04:54.150 PG host, capital PG database, and so on. 04:54.150 --> 04:56.190 And also double check all the keys on the left 04:56.190 --> 04:57.510 hand side as well. 04:57.510 --> 04:58.860 You make a typo inside this file 04:58.860 --> 05:00.840 it's gonna be a little bit of a pain to track 05:00.840 --> 05:01.680 down in the future. 05:01.680 --> 05:03.360 Please just do a quick double check inside of 05:03.360 --> 05:05.130 here and make sure you've got the correct spelling 05:05.130 --> 05:07.740 for stuff like say database on both sides and 05:07.740 --> 05:10.640 the correct spelling for password on both sides and so on. 05:11.550 --> 05:13.230 All right, so let's take a quick pause right here. 05:13.230 --> 05:14.880 We're gonna come back the next section and 05:14.880 --> 05:17.400 continue working on our server implementation. 05:17.400 --> 05:18.900 I'll see you in just a moment.