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[Intro Music]

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Alright guys, we have just explored

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the python container, and we have

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created a couple of sample Python

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applications. And now it's a good

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time to move on. And now let's try

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and run another container Node.js

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container. And let me first show

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you that at the moment, we don't

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have Node.js installed on this

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computer. If I'll type 'node

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-v', I'll see, 'command not

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found: node'. And that means that Node.js

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along with NPM actually are not

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installed on this computer. Now,

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let's suppose that you want to

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create the Node.js application and

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run it using node. But you don't

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want to install node on your

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computer. Or, for example, you want

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to run your application using a

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specific version of node that

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differs from the version that is

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installed on your computer. In

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such case Docker will help you.

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Let's now create Node.js

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container, and first let's pull Node.

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js image from Docker Hub. And let's

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create a very simple Node.js

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application that will print simply

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'Hello from Node.js application' to

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the terminal. Let's do that. Let's

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clear terminal. And let me

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first look at containers that

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are currently running. There are no

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such containers. But if I have a

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look at history, I will see a bunch

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of python containers. And let me

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prune them quickly. And for that we

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could use command 'docker container

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prune', like so. And all containers,

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stopped containers will be deleted.

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'docker ps -a', and now I see that

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there are no stopped containers. And

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notice that we have reclaimed

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around 10 megabytes of disk space

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that was utilized by those stopped

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containers. Great. Let me now clear

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terminal. And now let's pull Node.

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js image. And lets use first layer

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stack it is default one. 'docker

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pull node', Enter, 'Pulling from

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library/node'. And you see that this

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image has multiple 'fs' layers. Let's

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wait a bit until download and

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extraction will be completed.

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Meanwhile, let me tell you a few

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words about Node. Node.js is

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basically backend JavaScript

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framework that allows you pretty

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easily and faster create any

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JavaScript backend applications.

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And you're able, for example, create

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API using JavaScript and run it on

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your backend servers, or you could

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perform any operations with file

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system. And in this course, we will

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try to create a sample

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application that will create the

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new files in your working directory

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and so on. So that's Node.js. And

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usually it is used in conjunction

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with frontend JavaScript

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frameworks like React or Vue or

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Angular, and you're able to create

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the JavaScript microservices

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on frontend and on backend, that

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simplifies actually, entire

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development workflow. Okay, pull

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and extraction were completed, and

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now we have node image locally in

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our cache, and we could verify that

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'docker images'. And yes, here is

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node in this list. And you see that

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its size is approximately the same

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as size of python image. Here you

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see those sizes and both of them

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are around one gigabyte in size.

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Great. Let's now create the Node.js

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container and let's simply create it

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first using the 'docker run node'

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command, like so. 'docker run node',

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container was created, process was

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terminated, and container was

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stopped as well, as usually. 'docker

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ps', there are no containers

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running. Let's now run this

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container in interactive mode with

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options '-i' and '-t'. 'docker

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run -it node'. And now I see

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prompt, 'Welcome to Node.js v13.13.0'.

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And in your case, you

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may see another version, because

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tag 'latest' may be assigned to

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different images at different

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moments of time. For example, when

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there is a new stable version of

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image is released, then tag 'latest'

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is assigned to that new version.

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Great, you are able to type for

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example, 'help' here, '.help', and

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you'll see some basic commands that

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you are able to utilize in this

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Node.js interpreter, because we are

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actually connected now to Node.js

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interpreter. And we are able to

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execute some JavaScript commands

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directly here. For example, let's

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type console.log('Hello from Node.

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js container')', like so, press Enter.

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And you see 'Hello from Node.js

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container' here in terminal. Great.

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That's how we were able to connect

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to interactive shell inside of

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the Node.js container where you're

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able to execute any JavaScript

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commands, or you could type for

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example 10 + 5, and you should

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get 15 here in the terminal, or you

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could create a new variable, for

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example, let's create variable 'a' and

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assign the value to it, 10, and

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here we are able to access variable

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10 and in such case you will see

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its value here in the terminal.

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Great. Are you able to interact with

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Node.js

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interpreter? Let's go out of it.

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And actually you need to type a '.exit'

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in order to exit from this

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interactive shell like so. Process

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was terminated, and now container

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was stopped. 'docker ps', there are no

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containers running. Great. Let's

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next create the sample Node.js

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application, and run it using Node.

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js container. Let's do that next. Bye-Bye.

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[no audio]