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Now with the bind mount added,

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if we changed the HTML files,

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those changes are instantly reflected,

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when we reload the app here.

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You'll notice a problem though,

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if you change something in server JS.

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So Indy JavaScript code,

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which is executed by a note.

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Let's say there, for example,

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I simply want to console log, test here.

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Just to change anything.

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So I wanna Log test here,

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whenever we save a new feedback.

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Now my container is still up and running.

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You can always check this with Docker PS, of course.

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And therefore if I reload, and I try this,

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of course it works, but to now see whether,

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we also see that log.

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We can, of course now use Docker logs

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feedback-app.

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And we see nothing here.

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There is absolutely nothing.

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So somehow this wasn't logged.

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And that's a node specific problem,

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but you might face similar issues

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in other applications as well.

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This code in server JS is executed by node,

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by the node runtime.

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And it that runtime, and that file being executed.

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Which is responsible for us seeing this page

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and having a working web server.

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Now we need to restart the web server,

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to pick up changes in the JavaScript code

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that is used by that server.

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We don't need to restart the entire container,

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but just the web server.

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Now, if the container is already running,

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restarting just the server in that container,

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is not really trivial though.

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So actually, the best thing we can do here,

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is to simply stop that container

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and then restart it thereafter.

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At least we don't need to rebuild the image.

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But by stopping and restarting,

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we start a new node server,

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which will pick up this server JS file.

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But of course, since I added --rm

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when I created the container,

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actually we can't start it again,

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because it was deleted once I stopped it.

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So here I would have to run Docker, run again.

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But with that done, if I now reload,

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this should work.

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And I save here,

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we should now be able to see the logs.

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If we use Docker logs feedback-app.

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Here it is.

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So it's better than having to rebuild the entire image,

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but still not great.

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Now for note JS, that's a common problem though.

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And you might also be facing it

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if you're just developing locally without Docker at all.

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And there is a useful extra package,

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which we can use in node JS development,

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which will watch the file system,

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and which will restart the node server,

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whenever a file changed.

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It's a package which be used during development,

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therefore, to ensure that changes are reflected instantly.

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And for that here in packaged.json,

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you should add a devDependencies node,

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next to dependencies.

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And in their, add nodemon.

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And then the version 2.0.4, for example.

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That's now an extra dependency added to this project.

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And now we can run server JS,

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with this nodemon package,

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instead off with node itself.

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Under the hood nodemon of course uses node,

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but it has this extra file change watcher,

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which ensures that, we are made aware of

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changes in our files.

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For that We should add a script section,

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a scripts section to package.json as well.

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And in there add a script named start,

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and type nodemon server.js in here.

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And now we can run this script here

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to use nodemon, to start our server,

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Instead of node.

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With that done we now also need to tweak our Docker file,

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to utilize this new script

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and use this script to start our process,

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our server.

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Instead of using node.

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And they offer in the Docker file,

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the command you wanna execute is now actually npm start.

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Which uses this start script,

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which then under the hood uses nodemon.

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So if we now saved this,

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we need to remove our

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feedback-node:volumes image.

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And for that, of course, I first of all,

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needs to stop my feedback app container.

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Otherwise the image is still in use.

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So let's do that first.

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Then remove the image

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and then build the image again to pick up this new

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command here at the end.

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And once that is all done,

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we can of course use our Docker run command again,

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to bring this server back up,

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now using this latest image.

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And now the key difference is that

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this server should now automatically restart,

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whenever we change anything in server JS.

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So if I add a couple of exclamation marks here,

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for example, in this log statement,

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00:05:30,160 --> 00:05:31,673
and I saved this.

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If I now test 4,

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00:05:36,530 --> 00:05:37,743
test this.

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This all works,

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00:05:40,910 --> 00:05:45,010
but now if I run Docker logs feedback-app,

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we see these exclamation marks here.

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And we actually also see some output from nodemon,

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which proves that it works.

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00:05:52,010 --> 00:05:54,250
You'll see that it started and you'll see that it,

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00:05:54,250 --> 00:05:57,660
for example, restarted due to changes here.

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00:05:57,660 --> 00:06:00,810
Now I got an important note for windows users,

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00:06:00,810 --> 00:06:04,620
especially when you're using WSL2

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00:06:04,620 --> 00:06:07,480
for running Docker on windows.

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00:06:07,480 --> 00:06:08,480
If you're doing that,

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00:06:08,480 --> 00:06:10,060
you might notice that,

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00:06:10,060 --> 00:06:12,600
when for me, file changes

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00:06:12,600 --> 00:06:15,250
do reload D development server,

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00:06:15,250 --> 00:06:18,730
and everything does work as shown in the lecture,

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00:06:18,730 --> 00:06:20,950
it doesn't work for you.

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00:06:20,950 --> 00:06:24,680
The reason for that is that, when using WSL2,

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00:06:24,680 --> 00:06:28,612
you should store your project and your project files,

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00:06:28,612 --> 00:06:32,590
directly in the Linux file system

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00:06:32,590 --> 00:06:33,423
in the end.

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00:06:33,423 --> 00:06:36,180
So somewhere in the Linux file system,

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00:06:36,180 --> 00:06:39,700
not your regular windows file system.

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00:06:39,700 --> 00:06:43,540
Now you might wonder how you get to this Linux file system,

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00:06:43,540 --> 00:06:44,730
attached you'll find a link.

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00:06:44,730 --> 00:06:46,440
You find a link to this article,

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00:06:46,440 --> 00:06:50,700
which explains how you can mount and work

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00:06:50,700 --> 00:06:53,370
with this Linux file system.

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00:06:53,370 --> 00:06:56,610
Where if you then have your project in there,

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00:06:56,610 --> 00:07:00,610
your changes will propagate to the Docker container.

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00:07:00,610 --> 00:07:03,910
And therefore they should update as shown.

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00:07:03,910 --> 00:07:07,020
If you use the regular windows file system,

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00:07:07,020 --> 00:07:11,290
file changes are not propagated to the Docker container,

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00:07:11,290 --> 00:07:14,660
and therefore not picked up by tools like nodemon.