WEBVTT 00:04.350 --> 00:10.020 We have just created the very first topic in our coffeecake last term, and the name of this topic is 00:10.020 --> 00:12.360 Seeds for creation of this topic. 00:12.360 --> 00:18.410 We have used this command, we have used to Kafka topic script with several named arguments. 00:18.660 --> 00:24.900 Notice that in Shell you could specify named arguments with their desk prefixes like soul. 00:25.290 --> 00:32.250 And for example, here we have specified connection between for Bootstrap Sarah and that is a one of 00:32.250 --> 00:33.770 the Sarahs inside of the class. 00:34.320 --> 00:40.020 For now, we have only single Sarah inside of the cluster and of course each cluster must have at least 00:40.020 --> 00:41.310 one Ozaukee process. 00:41.700 --> 00:42.960 That's what we basically have. 00:43.410 --> 00:51.210 And also we named argument the topic we have specified name of the topic that we want to create. 00:51.630 --> 00:57.510 But now in this lecture, let me show you what exactly has happened in the coffeecake last year when 00:57.510 --> 00:59.050 we have entered this command. 00:59.490 --> 01:05.310 For that, let me go to looks for the work of Castro's looks or related to Kafka messages. 01:05.550 --> 01:09.580 Let me go one level up and the now to DMB. 01:10.050 --> 01:13.200 Kafka looks and least files here. 01:13.440 --> 01:18.930 Remember that we have observed contents of this folder before and there were only five files. 01:19.170 --> 01:23.670 But now there is a new folder called c.D Desk zero. 01:23.910 --> 01:28.790 Let's go to this folder, Zedi Cities Zero and list files now here. 01:29.100 --> 01:32.520 And as you see here, this folder contains several files. 01:32.640 --> 01:36.960 For example, this file with extension index and this file with extension. 01:36.960 --> 01:39.800 Look, let's try to read, for example, this file. 01:40.020 --> 01:43.260 Let me copy its name and cut and paste name. 01:43.620 --> 01:45.450 And now this file is empty. 01:45.900 --> 01:47.520 Let's try to read this file. 01:47.610 --> 01:50.580 Let me copy its name, cut and paste this name. 01:50.940 --> 01:52.950 This file is empty as well. 01:53.430 --> 01:58.470 And the reason for that is that we have not yet sent any messages to this see topic. 01:58.770 --> 02:05.580 And as soon as we will do so, Kafka will store new messages inside of those files and see this desk 02:05.610 --> 02:06.540 zero folder. 02:06.960 --> 02:11.690 But the way this folder has such weird name cities Desh Zero. 02:12.000 --> 02:13.170 Let me explain to them. 02:13.530 --> 02:17.940 Let's go to Visual Studio Code and open up several the properties file. 02:18.240 --> 02:21.060 And here, let's scroll down a bit to this line. 02:21.060 --> 02:23.880 No partitions equals sign one. 02:24.420 --> 02:30.090 This line means how many partitions will be created by default for every topic. 02:30.300 --> 02:36.840 But what is partition inside of every topic matter just can be spread among several partitions. 02:37.080 --> 02:41.670 And every partition is basically just separate folder like we see here. 02:42.120 --> 02:48.930 And in our case, Kafka has created just a single partition because by default, as you see here, number 02:48.930 --> 02:50.700 of partitions is set to one. 02:51.120 --> 02:56.970 If you try to change this default number, for example, to two, then you'll see here two folders with 02:56.970 --> 02:57.420 names. 02:57.420 --> 02:57.950 See this? 02:57.970 --> 03:00.450 There's zero and see this one. 03:00.810 --> 03:04.620 But again, by default, Kafka will create just single partition. 03:04.740 --> 03:09.960 But Dobek, this way here in this folder name we see psychic's zero. 03:10.080 --> 03:17.730 It is partitions number and there are no URLs or folders that Kafka has created in Kafka logs folder. 03:17.910 --> 03:21.540 There was just a single folder see Zero and Kafka. 03:21.540 --> 03:23.970 Did this do to this configuration parameter. 03:23.970 --> 03:26.310 No partitions equal sign one. 03:26.730 --> 03:27.540 OK, no. 03:27.540 --> 03:28.110 Let's proceed. 03:28.110 --> 03:34.070 And next, I'll show you how to read information about existing topics in Kafka Gloster. 03:34.290 --> 03:34.920 See you next. 03:35.040 --> 03:35.480 Bye bye.