LFW211 Course Feedback

federicopenaranda

Hi all, I found a couple of typos or issues in the course, I was posting those in the wrong forum , so I will post them here again. The goal of this is to give you feedback on the course, so it can be improved if my feedback have value. Here is the first one:

1) In the page of the link below, the text mentions a flatstr package, but I couldn't find that package in the list of packages that the page shows.
https://trainingportal.linuxfoundation.org/learn/course/nodejs-application-development-lfw211/packages-dependencies/packages-dependencies?page=4

2) In the lab 2 on "Key Javascript Concepts" are some lines of code that validates the script with some assert statements:
https://trainingportal.linuxfoundation.org/learn/course/nodejs-application-development-lfw211/key-javascript-concepts/lab-exercises?page=2

assert(Object.getOwnPropertyNames(felixProto).length, 1)
assert(Object.getOwnPropertyNames(felixProtoProto).length, 1)
assert(Object.getOwnPropertyNames(felixProtoProto).length, 1)
assert(typeof felixProto.meow, 'function')
assert(typeof felixProtoProto.purr, 'function')
assert(typeof felixProtoProtoProto.hiss, 'function')
console.log('prototype checks passed!')

I believe that it should be like this (I put the change in bold text on the line with an arrow):

assert(Object.getOwnPropertyNames(felixProto).length, 1)
assert(Object.getOwnPropertyNames(felixProtoProto).length, 1)
---> assert(Object.getOwnPropertyNames(felixProtoProtoProto).length, 1)
assert(typeof felixProto.meow, 'function')
assert(typeof felixProtoProto.purr, 'function')
assert(typeof felixProtoProtoProto.hiss, 'function')
console.log('prototype checks passed!')

Regards.

federicopenaranda

I found a typo in this page:

https://trainingportal.linuxfoundation.org/learn/course/nodejs-application-development-lfw211/nodes-module-systems/nodes-module-systems?page=6

I think the "url" part is missing:

const isMain = process.argv[1] &&
await realpath(fileURLToPath(import.meta.url)) ===
await realpath(process.argv[1])

It should be:

const isMain = process.argv[1] &&
---> await realpath(url.fileURLToPath(import.meta.url)) ===
await realpath(process.argv[1])

Regards.

federicopenaranda

The course is great, but I think the code examples could be changed to improved visibility, maybe something like this?:

Regards.

federicopenaranda

Found a little typo in:

https://trainingportal.linuxfoundation.org/learn/course/nodejs-application-development-lfw211/nodes-event-system/nodes-event-system?page=3

Original code:

ee.addListener('close', () => {
console.log(close event fired!')
})

Fixed (missing single quote after "close"):

ee.addListener('close', () => {
--> console.log('close event fired!')
})

Regards.

federicopenaranda

Found a little typo in:

https://trainingportal.linuxfoundation.org/learn/course/nodejs-application-development-lfw211/nodes-event-system/nodes-event-system?page=2

Original code:

const { EventEmitter } = require('events')
class MyEmitter extends EventEmitter {
constructor (opts = {}) {
super(opts)
this.name = opts.name
},
destroy (err) {
if (err) { this.emit('error', err) }
this.emit('close')
}
}

Fixed (extra comma before "destroy"):

const { EventEmitter } = require('events')
class MyEmitter extends EventEmitter {
constructor (opts = {}) {
super(opts)
this.name = opts.name
--> }
destroy (err) {
if (err) { this.emit('error', err) }
this.emit('close')
}
}

Regards.

a.taleghani

I want to THANK you! I was combing through my code wondering what I did wrong, if there was a typo on my end, frustrated so much until I looked through the course forum and saw that you are the ONLY person who posted about this! You saved me HOURS of headache and frustration! As a complete green (aside from the Intro Course Mr Clements also put together) I'm far away from being a senior engineer and likely wouldn't have caught this on my own and research would have been tedious. THANK YOU SO MUCH!!!!!!

federicopenaranda

@a.taleghani said:
I want to THANK you! I was combing through my code wondering what I did wrong, if there was a typo on my end, frustrated so much until I looked through the course forum and saw that you are the ONLY person who posted about this! You saved me HOURS of headache and frustration! As a complete green (aside from the Intro Course Mr Clements also put together) I'm far away from being a senior engineer and likely wouldn't have caught this on my own and research would have been tedious. THANK YOU SO MUCH!!!!!!

Wow!, I'm glad that those posts helped you!, that was the intention, to help others go through the course with less frustration facing these issues. You motivated me to keep doing it, thank you too for your message. Regards!.

federicopenaranda

In lab 14.1 the test.js file in line 7, "win32" value should be added to the regular expression, in case the lab is been used in Windows environment. Something like this:

assert.match(stdout.toString(), /^(d|w|l|aix|.+bsd|sunos|gnu|win32)/i, 'must output OS identifier')

federicopenaranda

On module 15, step "Process Configuration (1)" (https://trainingportal.linuxfoundation.org/learn/course/nodejs-application-development-lfw211/creating-child-processes/creating-child-processes?page=9) the example that should replace the env variables in the child process, well, doesn't, it shows the new defined variable "SUBPROCESS_SPECIFIC" among other variables:

Maybe this is because of my Windows environment?, I should try in linux.

federicopenaranda

On module 16, on "tap Test Library: req.js" step (https://trainingportal.linuxfoundation.org/learn/course/nodejs-application-development-lfw211/writing-unit-tests/writing-unit-tests?page=9) when running the test with tap I get a deprecated warning about using functions "ifError" and "strictDeepEqual", it says it should be replaced with "strictSame" and "error" respectively. I changed the code and works correctly with the suggested functions. I'm guessing my tap version is newer than the one used in the example.

federicopenaranda

On module 16, on "jest Framework: test/req.test.js" step (https://trainingportal.linuxfoundation.org/learn/course/nodejs-application-development-lfw211/writing-unit-tests/writing-unit-tests?page=12) there is no npm command that installs jest framework, so I'm guessing that this command is missing:

npm install --save-dev jest

test file runs after installing jest.

federicopenaranda

On module 16, on "Configuring package.json (2)" step (https://trainingportal.linuxfoundation.org/learn/course/nodejs-application-development-lfw211/writing-unit-tests/writing-unit-tests?page=15) an image showing the result of command "npm test" with tap is missing at the end of the page.

xdxmxc

thanks so much @federicopenaranda really appreciate it, the course has been updated multiple times which can make some of these types of mistakes easier. We'll be putting out a update soon with all of these fixed plus updating to Node 18

federicopenaranda

You are welcome, it's good to know those posts helped you guys improve the course, I'm looking forward to check the new version of the course. Regards.