Require file somewhere in the directory node.js - node.js

I have a file that is required in many other files, that are on different folders, inside the main directory.
Is there a way to just require the filename without having to write the relative path, or the absolute path? Like require('the_file'). And without having to go to npm and install it?

Create a folder inside your main directory , put the_file.js inside and set the NODE_PATH variable to this folder.
Example :
Let's say you create a ./libs folder within your main directory, you can just use :
export NODE_PATH = /.../main/lib
after that, you can require any module inside this directory using just :
var thefile = require('the_file')
To not have to do that every time, you'd have to add the variable to your .bashrc (assuming you're running a Unix system).
Or you can set a global variable inside your app.js file and store the path of your 'the_file' in it like so :
global.rootPath = __dirname;
Then you can require from any of your files using :
var thefile = require(rootPath+'/the_file')
These are the most convenient methods for me, short of creating a private npm, but there are a few other alternatives that I discovered when looking up an answer to your question, have a look here : https://gist.github.com/branneman/8048520

Related

how to avoid mixture of \ and / in file paths when joining paths in Docker containerized Python code

As far as I'm aware I'm using best practices to define paths (using raw strings) and how I go about joining them (using os.path.join()), e.g.
import os
fdir = r'C:\Code\...\samples'
fpath = os.path.join(fdir, 'fname.ext')
and doing so has not caused me any problems when running my code within a Python or command shell. If I print fpath to the console I get consistent use of \s in the path:
C:\Code...\samples\fname.ext
But when I run a Docker containerized version of the code and run the image I get the error:
FileNotFoundError: [Errno 2] No such file or directory:
'C:\Code\...\samples/fname.ext'
I don't understand why os.path.join() has used a / to join fdir and fname.ext when the rest of the path included \\. It doesn't do this when I run the code outside of the container.
I have tried using os.path.normpath():
fpath = os.path.join(fdir, 'fname.ext')
fpath = os.path.normpath(fpath)
as discussed here, and os.sep.join():
fpath = os.sep.join([fdir, 'fname.ext'])
as covered here, and Path().joinpath():
from pathlib import Path
fpath = Path(fdir).joinpath('fname.ext')
as well as Path() / 'path_to_add':
fpath = Path(fdir) / 'fname.ext'
as discussed here, but in every case I end up with the same result using os.path.join().
Can someone please help me to understand what is going on and how to create consistent paths that will work whether I run the code in Python in a Windows environment, or in a Docker container?
Update Nov. 16:
In trying to keep my question brief I think I've left out details that are crucial. Apologies to those who have kindly taken the time to offer suggestions based on my incomplete description of the problem.
My code needs to import/export files from/to directories that are defined within a user-specified configuration file.
So the configuration file has a section of code where the user defines variables and paths, e.g.
samplesDir = r"path-to-samples-directory"
The variables are stored in a dictionary of dictionaris and stored as a .json.
At the start of the code the user defines the key that selects the dictionary of interest so that at various parts in my code when a file needs to be imported/exported, the paths are at hand.
So back to my example, samplesDir is stored in the configuration dictionary, cfgDict, so all I need to do is append the file name:
sampleFpath = os.path.join(sampleDir, sampleFname)
and sampleFname is determined based on other variables.
Because of the dynamic nature of the variables (including directory paths and file paths), I think it rules out the use of static path defined in a .yml with Docker Compose.
Update Nov. 18:
It may help to include a few more details and some screenshots.
The above screenshot shows the file and folder structure of the src directory containing the source code, the main app.py script for command-line use, the Dockerfile, etc.
The configs folder contains JSON files that includes variables, paths to directories and files. The user can create configuration files either by copying an existing one and modifying the entries, or configuration files can be generated by calling config.py.
Within config.py I have pre-set variables and paths, so that the directory path to the configuration files (configs), sample files (sample_DROs) and others (e.g. fiducials) are all within src.
I don't anticipate any reason why the user would want to store the config files anywhere else, nor do I expect them to want to use different sample files (or move them elsewhere). However, they will undoubtedly create their own fiducials and may decide not to store them in the fiducials directory (i.e. somewhere not within the src directory).
Likewise I have pre-set the download directory (based on the parameters stored within the configuration files, files are fetched from a server and downloaded) to be the default Downloads directory:
rootDownloadDir = os.path.join(Path.home(), "Downloads", "xnat_downloads")
Those files are later imported, processed, and the outputs are (by default) exported into sub-directories within rootDownloadDir.
Within Dockerfile I set the working directory of the container to be that of the source code and copy all of the contents of src (with the exception of some directories defined in .dockerignore):
WORKDIR C:/Code/WP1.3_multiple_modalities/src
...
COPY . .
so that the structure of the container mimics that of WORKDIR:
Hence I have allowed for flexibility in import/export directories, and they are by default a combination of paths within and outside of the src directory. And so, the code executed within the container will need to access files both within and outside of src.
That said, I don't know what rootDownloadDir will look like when os.path.join(Path.home(), "Downloads", "xnat_downloads") is run within the container.
This has got me thinking - Is it bad practice to set the download directory outside of src?
Returning to the original error:
the sample file is in the container:
From the actual behavior I can suppose that the container is based on Unix-like image. Path separator is / in such systems.
To build an environment-independent path which works inside and outside of the container you need the following steps:
Mounting of host folder to container directory.
Environment variable inside and outside the container.
I can show an example of how this is achievable via docker-compose tool and its configuration file docker-compose.yml:
# docker-compose.yml file
version: '3'
services:
<service_name>: # your service name here
image: <image_name> # name of image your container is built on
environment:
- SAMPLES_PATH=/samples
volumes:
- C:\Code\somepath\samples:/samples
In your python code you can use the following structure:
import os
fdir = os.getenv('SAMPLES_PATH', r'C:\Code\...\samples')
fpath = os.path.join(fdir, 'fname.ext')

Node creating file 1 level up from the current path

I was using path.resolve but this command created a monster folder that can't be deleted called lib..
path.resolve(__dirname + "../assets/pic/" + `${fileName}.png`)
Question 1
What is the propper usage to create a folder 1 level up from the current path?
Question 2
How to remove the lib../assets/pic folder? Deleting the entire project or using git reset --hard, git stash doesn't work because Windows 10 says the folder doesn't exist.
Answer to Question 1:
tl;dr
const fs = require('fs')
const folderName1DirUp = '../SomeFolder'
try {
if (!fs.existsSync(folderName1DirUp)){
fs.mkdirSync(folderName1DirUp)
}
} catch (err) {
console.error(err)
}
The back story:
Two ways to reference the current folder in a Node.js script. You can use ./ or __dirname. Note in addition to ./ you can also use ../ which points to the parent folder.
The difference between the two.
__dirname in a Node script will return the path of the folder where the current JavaScript file resides.
./ will give you the current working directory (and ../ the parent). For ./ a call to process.cwd(). returns the same thing.
Initially the current working directory is the path of the folder where you ran the node command, but during the execution of your script it can change by calling process.chdir(...).
There is one place where ./ refers to the current file path which is in a require(...) call. There the ./, for convenience, refers to the JavaScript file path which lets you import other modules based on the folder structure.
Thus the call to fs.mkdirSync('../SomeFolder') with the given folder name makes a folder one level up from the current working directory.
Answer to Question 2:
From a PowerShell prompt Remove-Item './../Folder1UpToDelete' -Force The ./ is for the current folder. The ../ is for one folder up from the current. Finally the Folder1UpToDelete is the one folder up from the current that you want to delete. The -Force makes sure to delete all sub-folders/files under the folder you want deleted including hidden and/or read-only files.
To answer the first question, to create a path 1 level up, you can use path.join():
path.join(__dirname, "../assets/pics", `${fileName}.png`);
For the second question, if deleting it through the explorer doesn't work, you can try:
fs.rmdirSync("E:/path/to/broken/folder..");
Using Git Bash and running
cd /c/path/to/broken/
rmdir folder..

how I can prevent res.sendFile changing file path?

I'm using node.js and want to send file to the frontend. So I specified the direct path to my file like:
path = "c:/app/A"
and when I run res.sendFile(path, fileName);
I'm getting the Error: ENOENT: no such file or directory, stat '/home/projects/c:/app/A'
How I can disable this auto path adding "/home/projects" part?
I want to download file that is not in my project folder with my code. File is in my computer in different folder.
Try to use \\ as path delimiter for Windows (c:\\app\\A) and read about Node.js module "path".
so I need use just new URL(file:${"c:/app/A"});
so it will be like that:
let filename = "someName.com"
let absPath = "c:/app/someName.com";
fs.writeFileSync(`${filename}`, fs.readFileSync(new URL(`file:${absPath}`)));
res.download(`${filename}`, `${filename}`)

Creating A Folder In the Temp Folder

I'm trying to create a folder within the temp folder that doesn't have a random name.
Here is how I was trying to create the folder within the temp folder.
if not DirExists(ExpandConstant('{%tmp}\Utilities\SDK')) then
CreateDir(ExpandConstant('{%tmp}\Utilities\SDK'));
Log('Temp\Utilities\SDK Folder Has Been Created.');
I had a look at this thread, but even with the %, unfortunately, it still doesn't create the folder.The script compiles and runs as expected, however the folder doesn't create even though it says it has in the log file, I understand that the log file will say that because its told too, however, if the folder was unable to be created, wouldnt it crash? or return a false if an if statement was present?
With CreateDir() You must create dirs one after the other and not a dir structure at once.
if not DirExists(ExpandConstant('{tmp}\Utilities')) then
CreateDir(ExpandConstant('{tmp}\Utilities'));
if not DirExists(ExpandConstant('{tmp}\Utilities\SDK')) then
CreateDir(ExpandConstant('{tmp}\Utilities\SDK'));
if DirExists(ExpandConstant('{tmp}\Utilities\SDK')) then
Log('Temp\Utilities\SDK Folder Has Been Created.') else
Log('Temp\Utilities\SDK Folder ERROR : NOT Created.');
Inno Setup has a function to create a dir structure at once
function ForceDirectories(Dir: string): Boolean;
Example:
if not DirExists(ExpandConstant('{tmp}\Utilities\SDK')) then
ForceDirectories(ExpandConstant('{tmp}\Utilities\SDK'));
Also keep in mind :
{tmp} all is related to the Inno Setup Temp folder is-XXXXX.tmp
C:\Users\...\AppData\Local\Temp\is-XXXXX.tmp
{%temp} is the users Temp folder
C:\Users\...\AppData\Local\Temp
I think you want the Windows Temp and not the tmp from InnoSetup
{tmp}:
Temporary directory used by Setup or Uninstall. This is not the value of the user's TEMP environment variable. It is a subdirectory of the user's temporary directory which is created by Setup or Uninstall at startup (with a name like "C:\WINDOWS\TEMP\IS-xxxxx.tmp"). All files and subdirectories in this directory are deleted when Setup or Uninstall exits. During Setup, this is primarily useful for extracting files that are to be executed in the [Run] section but aren't needed after the installation.
So I think you want to do somethink like this:
if not DirExists(ExpandConstant('{%temp}\Utilities\SDK')) then
CreateDir(ExpandConstant('{%temp}\Utilities\SDK'));
Log('Temp\Utilities\SDK Folder Has Been Created.');

Node.js / Export configuration file

I have the following configuration file in /etc/sysconfig/myconf:
export USER=root
export NODE_DIR=/opt/MyDir
I want to use these setting in my .js file, which located in /opt/myapplication:
var userApp = //USER in /etc/sysconfig/myconf file
var dir = //NODE_DIR in /etc/sysconfig/myconf file
Is there any way to do it without open the file and parse it contents?
As I understand the export should give me the option to read it easily in node.js, but I don't find how (In addition, when I run export -p, I don't see these variables)
EDIT: what I search is equal Node.js's command to source command in Linux (the variables is not environment variables)
If those environment variables are available when you launch the program, you can use process.env. https://nodejs.org/api/process.html#process_process_env

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