Javascript questions which don't deserve their own thread.

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Suspicious Dish: Sep 24, 2011; 2020 is the year of linux on the desktop, bro; Fun Shoe

I don't see any element with the ID "leftSide". I only see an element with a class of "leftSide". You either need to add an ID or use document.querySelector(".leftSide")

# ? Feb 4, 2016 17:21

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# ? May 15, 2024 08:10

ModeSix: Mar 14, 2009

Suspicious Dish posted:

I don't see any element with the ID "leftSide". I only see an element with a class of "leftSide". You either need to add an ID or use document.querySelector(".leftSide")

Doh! Thank you so much, that makes perfect sense.

I'm completely new to javascript and I really appreciate your help.

ModeSix fucked around with this message at 17:25 on Feb 4, 2016

# ? Feb 4, 2016 17:22

Obliterati: Nov 13, 2012; Pain is inevitable.
Suffering is optional.
Thunderdome is forever.

ModeSix posted:

Doh! Thank you so much, that makes perfect sense.

I'm completely new to javascript and I really appreciate your help.

I am pretty new to js (and coding) and I run into problems like this all the time. One of the easiest ways to check what's going on in this situation is to call console.log(); on anything/everything involved in creating that variable so's you know where in the chain you're slipping up.

# ? Feb 4, 2016 17:31

Munkeymon: Aug 14, 2003; Motherfucker's got an
armor-piercing crowbar! Rigoddamndicu𝜆ous.

Well you have class="leftSide" but you're searching for ID, so probably change that.

e: dang you guys work fast

# ? Feb 4, 2016 17:31

HappyHippo: Nov 19, 2003; Do you have an Air Miles Card?

ModeSix posted:

Doh! Thank you so much, that makes perfect sense.

I'm completely new to javascript and I really appreciate your help.

Just to clarify in case it isn't obvious, since getElementById couldn't find the element it returned null, and that caused your error later when you tried to call appendChild on it.

Also since you're new to javascript, I strongly recommend you put "use strict"; at the beginning of your scripts. While it wouldn't have helped you out here, strict mode makes many common bugs easier to track down.

# ? Feb 4, 2016 17:46

Vulture Culture: Jul 14, 2003; I was never enjoying it. I only eat it for the nutrients.

ModeSix posted:

So I am doing an online course learning javascript, and one of the assignments is using DOM to add elements to a page.

I am getting an error when I load the page "Uncaught TypeError: Cannot read properly 'appendChild' of null".

I have the script waiting for the onload before executing.

Please help, this doesn't make any sense to me why this isn't working.

http://pastebin.com/m833DMJJ

Other people have already answered this, but in general, JSFiddle or Plunker or Codepen are a better place to put your JS code samples when you're asking for help because people can play with them right there without any extra work

# ? Feb 4, 2016 18:01

Wheany: Mar 17, 2006; Spinya^{ha^{ha^haha}ha}ha_{ha_{ha_haha}ha}ha!; Doctor Rope

Obliterati posted:

I am pretty new to js (and coding) and I run into problems like this all the time. One of the easiest ways to check what's going on in this situation is to call console.log(); on anything/everything involved in creating that variable so's you know where in the chain you're slipping up.

Sometimes, yes. But since the developer tools are already open, I would put a breakpoint there and just step through the code. In a loop it's a pain in the rear end, but in a simple case like that, it is very useful.

# ? Feb 4, 2016 18:13

Vulture Culture: Jul 14, 2003; I was never enjoying it. I only eat it for the nutrients.

Wheany posted:

In a loop it's a pain in the rear end

Only insofar as you have to set a conditional breakpoint to only break on the thing you want

# ? Feb 4, 2016 18:36

ModeSix: Mar 14, 2009

Vulture Culture posted:

Other people have already answered this, but in general, JSFiddle or Plunker or Codepen are a better place to put your JS code samples when you're asking for help because people can play with them right there without any extra work

Thanks, these will be infinitely useful.

# ? Feb 4, 2016 23:38

EVGA Longoria: Dec 25, 2005; Let's go exploring!

So I've got a site that's got an intermittent issue - scrolling gets disabled by a piece of javascript adding "overflow: hidden;" to the body in a style attribute. Unfortunately, the code base is huge, and we have a dozen+ third party scripts coming in. (It's a nightmare.)

Does anyone have a way, purely programmatically, that I could monitor a node and note the file and line number (or even just the code or function name) that's modifying it? MutationObservers can watch, but they don't seem to be able to identify the function that actually changed it.

I know I can do this with DOM breakpoints locally, but I'm having trouble reproducing it myself locally, so I'd rather have something I can put out and get reports back on.

# ? Feb 8, 2016 17:34

Heskie: Aug 10, 2002

EVGA Longoria posted:

So I've got a site that's got an intermittent issue - scrolling gets disabled by a piece of javascript adding "overflow: hidden;" to the body in a style attribute. Unfortunately, the code base is huge, and we have a dozen+ third party scripts coming in. (It's a nightmare.)

Does anyone have a way, purely programmatically, that I could monitor a node and note the file and line number (or even just the code or function name) that's modifying it? MutationObservers can watch, but they don't seem to be able to identify the function that actually changed it.

I know I can do this with DOM breakpoints locally, but I'm having trouble reproducing it myself locally, so I'd rather have something I can put out and get reports back on.

Could you use Chrome Dev Tools 'Break on..' on the body?

I think this breaks on the line of code causing the issue. It should be highlighted in the Sources tab.

# ? Feb 8, 2016 19:42

EVGA Longoria: Dec 25, 2005; Let's go exploring!

Heskie posted:

Could you use Chrome Dev Tools 'Break on..' on the body?

I think this breaks on the line of code causing the issue. It should be highlighted in the Sources tab.

Unfortunately, that then requires me to be able to reproduce it locally. It's an intermittent/rare issue, and I've yet to reproduce it myself.

I'm toying with the idea of using a phantomjs script to do reload the pages a few thousand times with a breakpoint until I can reproduce it, but I'm holding out hope there's something I can hook into.

# ? Feb 8, 2016 21:06

Skandranon: Sep 6, 2008; fucking stupid, dont listen to me

EVGA Longoria posted:

Unfortunately, that then requires me to be able to reproduce it locally. It's an intermittent/rare issue, and I've yet to reproduce it myself.

I'm toying with the idea of using a phantomjs script to do reload the pages a few thousand times with a breakpoint until I can reproduce it, but I'm holding out hope there's something I can hook into.

Are you sure it's a random fluke from your code, or is it possibly environmental?

# ? Feb 8, 2016 21:11

EVGA Longoria: Dec 25, 2005; Let's go exploring!

Skandranon posted:

Are you sure it's a random fluke from your code, or is it possibly environmental?

Doubt it's environmental - we have seen it with pretty much every browser/os combo under the sun. The problem is it's mostly coming through from feedback left by users, so we're not sure exactly how often it's happening. It's also on our legacy platform, so people have been reluctant to actually add real tracking on the issue.

I'm going to look into setting up a mutation tracker that can report when it occurs for us to get a true idea of how often it happens - but while I'm doing that, I figured I'd try to find something that could solve the issue. Since breaking on dom manipulation is possible, I was hoping there was a simple bit of code I could put out there that would at least give me a trace of modifying code.

# ? Feb 8, 2016 23:24

Sedro: Dec 31, 2008

You can get a stack trace programmatically by calling Error().stack, but I assume a mutation tracker runs asynchronously to the actual mutation code.

# ? Feb 8, 2016 23:50

Kobayashi: Aug 13, 2004; by Nyc_Tattoo

Is there a way to remove all event listeners from a page using the console? Specifically I'm thinking of lovely streaming sites that are filled with all kinds of onclick bullshit.

# ? Feb 9, 2016 04:10

EVGA Longoria: Dec 25, 2005; Let's go exploring!

Sedro posted:

You can get a stack trace programmatically by calling Error().stack, but I assume a mutation tracker runs asynchronously to the actual mutation code.

code:

Error
    at Error (native)
    at <anonymous>:5:17
    at Array.forEach (native)
    at MutationObserver.<anonymous> (<anonymous>:4:13)

Yeah, looks like the stack trace ends up being for the anonymous function so no joy.

Oh well, was a long shot. Thanks for the help.

# ? Feb 9, 2016 15:47

Vulture Culture: Jul 14, 2003; I was never enjoying it. I only eat it for the nutrients.

Sorry if this is super-obvious but have you used Chrome/FF dev tools to do a global search through loaded JS files for the string 'body'?

# ? Feb 9, 2016 16:09

EVGA Longoria: Dec 25, 2005; Let's go exploring!

Vulture Culture posted:

Sorry if this is super-obvious but have you used Chrome/FF dev tools to do a global search through loaded JS files for the string 'body'?

I've tried, but the problem comes in that there's 94 line results in the JS for 'body' on any given page, at a minimum, and most of that is 3rd party code that's coming through minified. I'm kind of bashing my head against it, but I'm not making headway.

# ? Feb 9, 2016 16:36

Wheany: Mar 17, 2006; Spinya^{ha^{ha^haha}ha}ha_{ha_{ha_haha}ha}ha!; Doctor Rope

EVGA Longoria posted:

I've tried, but the problem comes in that there's 94 line results in the JS for 'body' on any given page, at a minimum, and most of that is 3rd party code that's coming through minified. I'm kind of bashing my head against it, but I'm not making headway.

Enable pretty printing

Firefox, lower left corner

Chrome, middle-ish of the window, lower left corner of the source view (e: actually, that depends on whether you have the console visible in the debugger and how high it is)

# ? Feb 9, 2016 18:41

qntm: Jun 17, 2009

Wheany posted:

Enable pretty printing

Firefox, lower left corner

Chrome, middle-ish of the window, lower left corner of the source view (e: actually, that depends on whether you have the console visible in the debugger and how high it is)

Cripies, that's the least discoverable option I've ever seen. Thank you for pointing it out.

# ? Feb 9, 2016 19:37

aBagorn: Aug 26, 2004

So what's the best way to extract binary data from XML and pass it on to an API?

My application is basically functioning as a bridge between two APIs, I make a call to the first, and the response is along these lines:

code:


<root>
    <something>
         <data> 
             **binary data here (base64 encoded string)
        </data>
    </something>
</root>

I need to pull the contents of the data element and then pass it along to the email manager API, which will include it as an attachment.

E: I figured it out. I was having issues because the base64 string I was pulling out was too big for the default limit for my other API. Increased the parser size limit and worked like a charm

aBagorn fucked around with this message at 21:22 on Feb 14, 2016

# ? Feb 12, 2016 23:44

Raskolnikov2089: Nov 3, 2006; Schizzy to the matic

I'm making multiple API calls inside of a Promise.all (thank you bluebird). Currently I'm saving the response objects to separate JSON files. I need to clean up the data some before it's ready for postgres. It feels really dumb and bulky to write to the separate JSON files with FS, only to turn around and gently caress with them immediately after.

Is there a node module or best practice that would allow me to perform simple filter/maps operations on the response objects I get back as I get them so I can skip the writing with FileSystem step?

I mean I guess I could just try to parse it inside of the promise but it seems messy.

# ? Feb 15, 2016 01:04

Skandranon: Sep 6, 2008; fucking stupid, dont listen to me

Raskolnikov2089 posted:

I'm making multiple API calls inside of a Promise.all (thank you bluebird). Currently I'm saving the response objects to separate JSON files. I need to clean up the data some before it's ready for postgres. It feels really dumb and bulky to write to the separate JSON files with FS, only to turn around and gently caress with them immediately after.

Is there a node module or best practice that would allow me to perform simple filter/maps operations on the response objects I get back as I get them so I can skip the writing with FileSystem step?

I mean I guess I could just try to parse it inside of the promise but it seems messy.

I wouldn't process them inline, but you can easily break the processing out to a separate function. You can also have the promises aggregated by bluebird broken out to separate functions to further make things pretty. There isn't really any other way to do what you want, any node module you could be imagining is just going to provide wrappers that essentially process the data in the promises.

# ? Feb 15, 2016 01:31

Odette: Mar 19, 2011

Skandranon posted:

I wouldn't process them inline, but you can easily break the processing out to a separate function. You can also have the promises aggregated by bluebird broken out to separate functions to further make things pretty. There isn't really any other way to do what you want, any node module you could be imagining is just going to provide wrappers that essentially process the data in the promises.

I made a small website parser that demonstrates this functionality. What you want to look at is getStory in fictionpress-scraper.js.

# ? Feb 15, 2016 02:01

Raskolnikov2089: Nov 3, 2006; Schizzy to the matic

Skandranon posted:

I wouldn't process them inline, but you can easily break the processing out to a separate function. You can also have the promises aggregated by bluebird broken out to separate functions to further make things pretty. There isn't really any other way to do what you want, any node module you could be imagining is just going to provide wrappers that essentially process the data in the promises.

The more experience I get with back-end, the more I realize how inelegant and ugly it all is.

It's kind of reassuring in a way. I keep feeling like my approach is super hacky and amateurish and then I see other implementations and realize I wasn't far off the mark.

# ? Feb 15, 2016 20:40

Raskolnikov2089: Nov 3, 2006; Schizzy to the matic

Working with API rate limits, is wrapping my requests in a setTimeout a bad way to go about it?

# ? Feb 19, 2016 04:13

Skandranon: Sep 6, 2008; fucking stupid, dont listen to me

Raskolnikov2089 posted:

Working with API rate limits, is wrapping my requests in a setTimeout a bad way to go about it?

Depends how you are doing it? It doesn't magically solve your problems, it depends how you are using them.

# ? Feb 19, 2016 04:22

MrMoo: Sep 14, 2000

Raskolnikov2089 posted:

Working with API rate limits, is wrapping my requests in a setTimeout a bad way to go about it?

Not many APIs available, one can add requestIdleCallback to better integrate with animation if you are not calling in a service worker.

# ? Feb 19, 2016 15:21

ModeSix: Mar 14, 2009

Angular is a whore.

So I am trying to do form validation and take the form data and use push() to an array.

It appears to work fine, but two problems.
1) The form doesn't get cleared (this isn't really important yet so I'm not even going to focus on it in this question)

2) When I hit submit it appears to append the data to the array, because it can be sorted, filtered etc. But if I modify what is in the form, it changes the data in the array.

I tried to set up a jsfiddle but I really don't get it, so here's my HTML.

http://pastebin.com/c4N6s0xh

Now here's the script.

http://pastebin.com/gC4KRSRg

The console log shows the form data correctly, and it actually moves the data up into the array (or so it appears). If I modify any data that is in the form the corresponding array data is changed for the new entry. I also cannot submit a second additional entry, just one submission and that's it.

I really am stumped because this should work based off of everything I've read.

# ? Feb 19, 2016 16:11

IronDoge: Nov 6, 2008

You have to reset the model of the newcomment object after the submit, like so:

code:

$scope.newcomment.author = "";
$scope.newcomment.comment = "";

Also when you're appending the object to the array, you need to make a copy of it. Otherwise you're linking your new comment to the results array and it'll just change to whatever is being typed in your form.

See my changes here:
http://codepen.io/jowang/pen/jWoKPm?editors=1111

I believe in JSFiddle you have to bootstrap the Angular app to get it to work:
https://docs.angularjs.org/guide/bootstrap

IronDoge fucked around with this message at 16:57 on Feb 19, 2016

# ? Feb 19, 2016 16:39

Munkeymon: Aug 14, 2003; Motherfucker's got an
armor-piercing crowbar! Rigoddamndicu𝜆ous.

IronDoge posted:

I believe in JSFiddle you have to bootstrap the Angular app to get it to work:
https://docs.angularjs.org/guide/bootstrap

Nah, you just have to set Load Type to nowrap https://jsfiddle.net/v1adfpj1/

# ? Feb 19, 2016 17:38

ModeSix: Mar 14, 2009

IronDoge posted:

You have to reset the model of the newcomment object after the submit, like so:
code:
$scope.newcomment.author = "";
$scope.newcomment.comment = "";
Also when you're appending the object to the array, you need to make a copy of it. Otherwise you're linking your new comment to the results array and it'll just change to whatever is being typed in your form.

See my changes here:
http://codepen.io/jowang/pen/jWoKPm?editors=1111

I believe in JSFiddle you have to bootstrap the Angular app to get it to work:
https://docs.angularjs.org/guide/bootstrap

Oh wow, thank you so much!

I was originally trying to do what you've shown me, but I couldn't figure out the syntax for it, but now that I see what you've written it's really clear and makes a lot of sense.

Also, thanks for showing me codepen, seems more intuitive than jsfiddle.

ModeSix fucked around with this message at 17:43 on Feb 19, 2016

# ? Feb 19, 2016 17:38

Knifegrab: Jul 30, 2014; Gadzooks! I'm terrified of this little child who is going to stab me with a knife. I must wrest the knife away from his control and therefore gain the upperhand.

Edit nevermind but I do have anohter question.

I am using node to spawn a child process that is creating an ssh tunnel. However it needs a password (no keys cannot be used in this system). How do I tell node to supply ssh with a password (since there is no additonal command line parameters for passing a password), and I cannot get any additional packages like sshpass.

Knifegrab fucked around with this message at 03:35 on Feb 25, 2016

# ? Feb 25, 2016 00:23

necrotic: Aug 2, 2005; I owe my brother big time for this!

Knifegrab posted:

Edit nevermind but I do have anohter question.

I am using node to spawn a child process that is creating an ssh tunnel. However it needs a password (no keys cannot be used in this system). How do I tell node to supply ssh with a password (since there is no additonal command line parameters for passing a password), and I cannot get any additional packages like sshpass.

You would have to re-implement what SSHPass does: "Sshpass utilizes the pty(7) interface to control the TTY for ssh"

There is no other way.

# ? Feb 25, 2016 21:34

Suspicious Dish: Sep 24, 2011; 2020 is the year of linux on the desktop, bro; Fun Shoe

Why the OpenSSH guys don't bother creating a usable SSH library, I don't know.

# ? Feb 25, 2016 22:46

DONT THREAD ON ME: Oct 1, 2002; by Nyc_Tattoo; Floss Finder

Suspicious Dish posted:

Why the OpenSSH guys don't bother creating a usable SSH library, I don't know.

Well, it turns out that may have been a very good thing.

# ? Feb 26, 2016 00:09

Suspicious Dish: Sep 24, 2011; 2020 is the year of linux on the desktop, bro; Fun Shoe

MALE SHOEGAZE posted:

Well, it turns out that may have been a very good thing.

why

# ? Feb 26, 2016 04:26

ModeSix: Mar 14, 2009

Suspicious Dish posted:

why

http://heartbleed.com/

# ? Feb 27, 2016 06:38

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# ? May 15, 2024 08:10

Suspicious Dish: Sep 24, 2011; 2020 is the year of linux on the desktop, bro; Fun Shoe

ModeSix posted:

http://heartbleed.com/

what does an unrelated library have to do with anything

# ? Feb 27, 2016 06:43

The Something Awful Forums > Discussion > Serious Hardware/Software Crap > The Cavern of COBOL > Javascript questions which don't deserve their own thread.

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