WEBVTT 00:00.200 --> 00:00.920 Hey, everyone. 00:00.920 --> 00:02.450 And welcome back. 00:02.450 --> 00:09.650 Now, in the earlier lecture, we basically used our browser to look into how the cache control header 00:09.650 --> 00:10.700 really works. 00:10.730 --> 00:20.060 Now, in today's lecture we will be configuring our own Nginx Docker instance to include various kind 00:20.060 --> 00:23.690 of cache control headers and we'll start with no store for now. 00:24.140 --> 00:25.640 So let's go ahead. 00:25.640 --> 00:29.040 I have my docker nginx container up and running. 00:29.060 --> 00:34.640 Now before we start, what we'll do is we'll download these two images. 00:36.170 --> 00:37.970 So let's do one thing. 00:37.970 --> 00:41.240 So I have one image called as MC dot jpeg. 00:41.630 --> 00:49.010 I'll copy the URL and I'll do a wget perfect. 00:49.010 --> 00:53.390 And similarly I'll copy the node store dot PNG. 00:55.970 --> 00:56.510 Perfect. 00:56.510 --> 00:59.120 So I have done wget for both of them. 00:59.120 --> 01:04.320 So you'll see both of these files are part of my docker. 01:05.550 --> 01:15.090 Now just to avoid confusion, what I'll do, I'll rename the file called as Docker seed dot jpg and 01:15.240 --> 01:18.660 I'll rename node store to Docker. 01:19.110 --> 01:22.410 No store dot jpg dot PNG. 01:23.610 --> 01:24.420 Perfect. 01:24.450 --> 01:27.450 Now we have both the files up and running. 01:27.450 --> 01:37.680 Now just to verify if everything is working, I'll do a curl hyphen i on http example.com 01:39.810 --> 01:41.760 docker dot jpg. 01:43.380 --> 01:49.320 You got a proper response and you will see there is no cache control header over here. 01:49.830 --> 01:58.230 Similarly, I'll do a docker node store dot PNG and again you'll see there is no cache control header 01:58.230 --> 01:58.830 over here. 01:58.830 --> 02:06.090 So whenever you open this file in the browser, the browser will store the file in the cache depending 02:06.090 --> 02:08.310 upon its own configuration. 02:08.310 --> 02:14.970 So what we will be doing is for this specific file or for this extension, PNG extension, we will be 02:14.970 --> 02:20.820 adding a new header called as cache control header, which signifies a no store directive. 02:21.000 --> 02:23.580 So let's look into how we can do that. 02:23.610 --> 02:26.280 So I'll go to our Nginx configuration. 02:28.560 --> 02:36.390 And if you look into labs dot conf, we don't really have an explicit headers which are mentioned, 02:36.570 --> 02:39.630 so we'll go ahead and create our own header. 02:40.500 --> 02:51.600 So I'll say location for all the locations which ends with PNG or for all the extensions which end with 02:51.630 --> 02:52.080 PNG. 02:52.740 --> 02:57.110 I'll say root is for websites. 02:58.170 --> 03:07.810 So this specific aspect I copied from here and there is one important configuration which is add header. 03:07.830 --> 03:15.090 So add header will specify adding of new header in the response. 03:15.270 --> 03:17.310 Now I'll say cache control. 03:21.110 --> 03:24.890 And let me. 03:28.050 --> 03:39.270 This actually is a problem with Nano somehow in Docker when you use the CMD. 03:39.660 --> 03:42.870 So cache control will be no stored. 03:43.830 --> 03:44.370 Okay. 03:44.910 --> 03:47.520 And I'll close the file. 03:49.410 --> 03:51.300 Let me do a nginx hyphen t. 03:51.540 --> 03:54.750 Everything seems to be successful and I'll do a service. 03:54.750 --> 03:55.710 Enginex restart. 03:56.040 --> 03:56.790 Perfect. 03:56.790 --> 03:59.560 So things seems to be working correctly now. 03:59.580 --> 04:00.690 Let's do one thing. 04:00.690 --> 04:02.940 Let's do a docker node store. 04:03.090 --> 04:11.580 And now what you see is you see there is a new header called as cache control and the value is no stored. 04:11.680 --> 04:14.310 Now we did one mistake. 04:14.340 --> 04:16.620 There seems to be two colon over here. 04:16.770 --> 04:18.840 This is not expected. 04:20.640 --> 04:21.750 So. 04:26.350 --> 04:30.370 So this is something which we added by mistake. 04:30.700 --> 04:33.460 I'll just restart Nginx. 04:36.720 --> 04:38.790 And let's try this out. 04:38.820 --> 04:39.990 And perfect. 04:39.990 --> 04:45.810 So now we have a perfect cache control header for Docker node store dot PNG. 04:45.960 --> 04:55.200 So as expected, browser should follow this header and it should not store the docker node dot PNG. 04:55.470 --> 05:05.250 However, when you talk about the docker dot jpg it as it does not have a cache control header browser 05:05.250 --> 05:08.880 will go ahead and store this file in its cache. 05:09.270 --> 05:11.530 So let's try this out. 05:11.550 --> 05:24.630 I'll copy this URL and let's close the earlier terminal and I'll paste the URL Docker seed dot jpg. 05:24.660 --> 05:25.020 Perfect. 05:25.020 --> 05:26.970 So now we have the image. 05:27.090 --> 05:39.610 Correspondingly, we'll copy the second URL, which is Docker node store and I'll paste it again in 05:39.610 --> 05:41.590 my chrome. 05:41.620 --> 05:42.220 Perfect. 05:42.220 --> 05:45.280 So now we have both the images which you will see. 05:45.310 --> 05:54.970 However, if you do a about cache, since these are the key, I'll just copy the URL so you have the 05:55.000 --> 05:56.140 URL over your docker. 05:56.530 --> 05:56.920 JPG. 05:56.950 --> 05:59.890 You see the Chrome has cached this entry. 05:59.920 --> 06:07.090 However, now if I do you see I do not really get any result over here. 06:07.330 --> 06:12.940 And this is what the no store header basically is all about. 06:13.960 --> 06:24.700 So last thing just to reconfirm, the ad header is basically used to add a header in the response. 06:24.730 --> 06:28.630 Now it will not add header for all the response. 06:28.630 --> 06:34.390 It will only add header for the response with the extension dot PNG. 06:34.390 --> 06:44.680 So you have a location which is specific for extension dot PNG files and specific for any file which 06:44.680 --> 06:45.820 ends with PNG. 06:46.150 --> 06:52.510 The ad header directive will be included, so go ahead and try this out. 06:52.510 --> 06:55.750 This is quite interesting and fun to do. 06:55.870 --> 07:02.080 I hope this has been informative for you and I look forward to see you in the next lecture with the 07:02.080 --> 07:04.930 next cache control directives.