I am a new to Node JS. I have included a module via npm install '<module_name>. It was built correctly and there was no errors. Now, I wanted to debug it, so I placed a few console.log('some text') in code blocks of the module to see if the code by passes that line. Anyway, none of the log statements were displayed.
I am wondering if I have to compile or something the modules after adding the log staements. Am I missing something here.
Your console.log statements are not being run, this could be caused by many things.
Assuming you have added the console.log statements to the module code in the node_modules directory of your app..
does the module have src and dist directories and you have not edited the code that is actually being run? (this relates to needing to recompile, but editing the actual code that the module is running will be quicker and easier)
if this is in a server or long running script it will need to be restarted to load the changes
is this in a browser which might be caching the code (turn off browser cache)
is the code where you added the log statements actually being hit?
I would make sure I had a console.log statement in a part of the code guaranteed to be hit, just as a sanity check.
For anyone coming here in the future, try console.error instead of console.log. For some decided reason or another, log was being overriding by the library I was monkey fixing. Took me way too long to find the culprit.
Related
I'm seeing the mentioned error, with stack trace below
Error: Cannot find module 'src/auth/guards/jwt-auth.guard'
Require stack:
~/Documents/Code/nestjs-passport-learning/dist/src/user/user.service.js
~/Documents/Code/nestjs-passport-learning/dist/src/user/user.module.js
~/Documents/Code/nestjs-passport-learning/dist/src/app.module.js
~/Documents/Code/nestjs-passport-learning/dist/src/main.js
at Function.Module._resolveFilename (node:internal/modules/cjs/loader:939:15)
This error makes no sense, though, as the user module/service is not looking for that auth file at all. It was at one time, but I removed it while trying to debug the error. It seems like something internal to node itself is bugged and still looking at an outdated version of the code.
What happened:
Code was working/running perfectly
I decided to add "UseGuards(JwtAuthGuard)" to one of my user.service methods
At the same time I decided to setup debugging, so I added a launch.json file
Tried running the code. It built, but had a ton of "can't find bla bla" errors at runtime.
I stopped the app and figured the error was do to me not exporting the class in auth.module and not importing the AuthModule in UserModule(which was true).
I fixed that error, and restarted
Now getting the error message above
I removed the "UseGuards(JwtAuthGuard)" and all imports to it and AuthModule import in UserModule, as well as the launch.json file(ie revert back to exactly the code that was running perfectly 10 minutes earlier)
Still getting the same error(despite there being nothing in the user module that looks for it.
Why is user.service.ts still looking for that jwt-auth.guard.ts file?
Other things I've tried:
removing the "jwt-auth-guard.ts" file itself
checking out an earlier version of the code where "jwt-auth-guard.ts" hadn't even been written yet
restarting my machine
Nothing worked, no matter what, I get that same error, despite the code not being any different the code that worked.
link to github repo
Any help would be greatly appreciated, as I have no idea what's going on, and no idea what to google to even try to fix this problem.
Alright, so after some fiddling in my application, I tried renaming my 'dist' folder to try it, and it worked! So I guess the "caching" was due to the dist folder.
Peace and happy coding!
I have managed to build my angular app out as a dev build. I haven't done it as a production build yet as it gives me a few errors and i just need to test the dev build.
The dev build process goes fine, no errors or anything. I then use the files from the dist folder in a nginx docker container to host the files.
The problem is nothing is displayed but a white page and in the console i get an error saying 'Uncaught TypeError: Cannot read property 'id' of undefined'. The full message below doesn't seem to point to anything i have written and i've spent several hours searching online but can't find anything on this problem.
I've tried a few different things such as running 'npx ivy-ngcc' which i read manually compiles some stuff. Is there anyway i can get more details on the error to see if it's something i have done?
UPDATE
So i have restored the line that i commented out in main.ts as mentioned in the comments below. I have also tried 'ng build --aot' as suggested which presents me with a series of errors that all seem to relate to devextreme components that are used. I find this strange as i started the project with the devextreme angular starter project from github.
i get messages such as:
'dx-scroll-view is not a valid HTML element'
'node_modules/devextreme-angular/ui/drawer.d.ts - error: appears in
the NgModule.imports of SideNavOuterToolbarModule, but could not be resolved to an NgModule class'
If you go in the devtools and click on Sources, "Don't pause on exceptions" and check "Pause on caught expecptions" and continue until you get the "id error" you will find what module the error is thrown. In my case was a third party library called 'ngx-card/ngx-card' and it's module was the cause of the error (CardModule). Hope this will help find at least the cause of the error
I managed to solve the problem by disabling ivy in the angular compilation options. As soon as i did that it worked building both dev and production versions and is now working perfectly within Nginx.
Thanks to everyone who offered help :)
In tsconfig.json of your Angular project, put this to disable Ivy, the new Angular template engine
{
...
"angularCompilerOptions": {
"enableIvy": false
}
}
Typically, if it's not something that you've written, it tends to be an issue w/ your implementation - i.e. "Visiting a food vendor and ordering a food item they don't provide".
I know it's not a specific answer, but ensuring that you have appropriately configured things in your app.module would be a good first step. Perhaps attempting to build w/ AOT will also give you some more verbose failures that stem from attempting to build out.
Hopefully this helps another poor soul.
To anyone using devextreme, make sure you update your version to at least 19.2.5
https://github.com/DevExpress/devextreme-angular/issues/975#issuecomment-580172291
Starting with version 19.2.5 we support the IVY compiler.
I had the same issue and fixed it by changing from
loadChildren: './app/page/account/account.module#AccountModule'
to
loadChildren: () =>
import('./app/page/account/account.module').then(
(m) => m.AccountModule
)
in app-router.module.ts
The root cause of your error is very likely to be a module that you needed to load explicitly but didn't, or a circular reference in your own modules. Rodrigo has a good answer but to be more specific, you need to find the registerNgModuleType function in Angular's core.js and set a conditional breakpoint on the first line. The condition should be !ngModuleType || !ngModuleType.ɵmod. (You can set a conditional breakpoint in most modern browsers by right-clicking the line number.)
Once you've paused execution just before the exception happens, you can look at the value of ngModuleType if it's not undefined, or walk up a frame or two in the scope and see what the value of imports was.
For me, this issue occurred while using Storybook.
The reason it happened was because of the way I was precompiling the node modules. I was doing:
Incorrect
ngcc --properties es2015 browser module main --first-only
Correct
ngcc
Using this approach fixed it
i wanted to implement an hot-reload feature in my app.
Basically when i change a file that returns a value i want it to be working on my running application.
This involves some require.cache knowledge that maybe i got wrong,
i've found a small repo that i thought it could help me with no chance.
The repo is clear-module and i prepared a small example on top of it
git clone git#bitbucket.org:giggioz/test-clear-module.git
install the modules with
npm i
and then run it with
node index.js
This code prints every 500ms a value.
This value comes from a delegate.
My Issue
If i change the value returned by get-points.js while the code is running it does not do anything... i would expect a change, right?
Thanks for your help!
So Flow only works correctly the first time I run it, and then I have to restart my computer before it'll work correctly again.
Specifically, the problem I'm seeing is that we are using the Flow language to add type annotations to our JS code. Our linter script is setup to run flow type checking among other things. However, when I fix an issue in my code and then rerun the linter script, it still comes back with the exact same errors... BUT when it shows the piece of code where the error is supposed to be, it actually shows my updated code that's fixed.
So as an example, I had a file I copied into the project, that I didn't think I really needed, but maybe I would. So I copied it in just in case. Well then it came up with a bunch of linter errors, so I decided to just delete the file since I didn't really need it. So then I run "yarn lint --fix" again, but it's still complaining about that file, EVEN THOUGH THE FILE DOESN"T EXIST! Now interestingly, where the linter output is supposed to show the code for those errors it's just blank.
Or another example, let's say I had a couple of functions in my code:
100: function foo() {}
...
150: function bar() {}
And foo has a lot of errors because it was some throw away code I don't need anymore and so I just delete it. So the new code looks like:
100: function bar() {}
Well I rerun the linter and get an error like:
Error ------------------------ function foo has incorrect
something...blah blah
src/.../file.js
100| function bar() {}
I also tested this out on a coworker's machine and they got the same behavior that I did. So it's not something specific to my machine, although it could be specific to our project?
Note: There doesn't appear to be a tag for Flow, but I couldn't post without including at least one tag, so I used flowlang even though that's actually a different language :-( I'm assuming that anyone looking for flow would also use that tag since it's the closest.
The first time you launch Flow it starts up a background process that is then used for subsequent type checking. Unfortunately this background process is extremely slow, and buggy to boot. In linux you can run:
killall flow
To stop the background process. Then if you rerun the flow type checker, it will actually see all your latest changes.
This gist shows a code snippet that dumps an object into a CSV file.
File writing is done using module csv-write-stream and it returns a promise.
This code works flawlessly in all the Mocha tests that I have made.
When the code is invoked by the main nodejs app (a server-side REPL application involving raw process.stdin and console.log invocations as interaction with the user), the CSV file is created, but it's always empty and no error/warning seems to be thrown.
I have debugged extensively the REPL code with node-debug and the Chrome dev tools: I am sure that the event handlers of the WriteStream are working properly: no 'error', all 'data' seems to be handled, 'close' runs, the promise resolves as expected.
Nevertheless, in the latter case the file is always 0 bytes. I have checked several Q&A's and cannot find anything as specific as this.
My questions are:
can I be missing some errors? how can I be sure to track all communications about the file write?
in which direction could I intensify my investigation? which other setup could help me isolate the problem?
since the problem may be due to the presence of process.stdin in the equation, what is a way to create a simple, light-weight interaction with the user without having to write a webapp?
I am working on Windows 7. Node 6.9.4, npm 3.5.3, csv-write-stream 2.0.0.
I managed to fix this issue in two ways, either by:
resolving the promise upon the 'finish' event of the FileWriteStream rather than on the 'end' event of the CSVWriteStream
removing the process.exit() I was using at the end of my operations with process.stdin (this implies that this tutorial page may be in need of some corrections)