Node.js: Python not found exception due to node-sass and node-gyp

Question

so this happened to me on windows recently. I fix it by following the following steps using a PowerShell with admin privileges:

1. delete node_modulesfolder
2. running npm install --global windows-build-tools with administrative privilege. (in my case need restart - and restart without ask!!!)
3. reinstalling node modules or node-sass with npm install

The error message means that it cannot locate your python executable or binary.

In many cases, it's installed at c:\python27. if it's not installed yet, you can install it with npm install --global windows-build-tools, which will only work if it hasn't been installed yet.

Adding it to the environment variables does not always work. A better alternative, is to just set it in the npm config.

npm config set python c:\python27\python.exe

My machine is Windows 10, I've faced similar problems while tried to compile SASS using node-sass package. My node version is v10.16.3 and npm version is 6.9.0

The way that I resolved the problem:

1. At first delete package-lock.json file and node_modules/ folder.
2. Open Windows PowerShell as Administrator.
3. Run the command npm i -g node-sass.
4. After that, go to the project folder and run npm install
5. And finally, run the SASS compiling script, in my case, it is npm run build:css

And it works!!

Node-sass tries to download the binary for you platform when installing. Node 5 is supported by 3.8 https://github.com/sass/node-sass/releases/tag/v3.8.0 If your Jenkins can't download the prebuilt binary, then you need to follow the platform requirements on Node-gyp README (Python2, VS or MSBuild, ...) If possible I'd suggest updating your Node to at least 6 since 5 isn't supported by Node anymore. If you want to upgrade to 8, you'll need to update node-sass to 4.5.3

I had to:

Delete node_modules
Uninstall/reinstall node
npm install [email protected]

worked fine after forcing it to the right sass version, according to the version said to be working with the right node.

NodeJS  Minimum node-sass version   Node Module
Node 12 4.12+   72
Node 11 4.10+   67
Node 10 4.9+    64
Node 8  4.5.3+  57

There was lots of other errors that seemed to be caused by the wrong sass version defined.

node-gyp requires old Python 2 - link

If you don't have it installed - check other answers about installing windows-build-tools.

If you are like me and have both old and new Python versions installed, chances are that node-gyp tries to use Python 3. And that results in the following SyntaxError: invalid syntax error.

I found an article about having two Python versions installed. And they recommend renaming Python 2.* executable to python2.exe - link.

So it looks like node-gyp is expecting to find old Python 2 executable renamed. Hence the error message:

...
gyp verb check python checking for Python executable "python2" in the PATH
gyp verb `which` failed Error: not found: python2
...

Once I renamed C:\Python27\python.exe to C:\Python27\python2.exe it worked without errors.

Of course, both C:\Python27\ and C:\Python39\ have to be in PATH variable. And no need in setting old Python version in npm config. Your default Python still will be the new one.

You need to follow the below steps to fix the error:

    1: DELETE node_modules
    2: npm install node-sass@<version-as-per-below-table>
    3. npm install

Every node-sass version corresponds to a specific Node.JS build.

Below is a quick guide for minimum and maximum support supported version of node-sass (Check updates to below table here) :

---

| NodeJS  | Supported node-sass version | Node Module |
|---------|-----------------------------|-------------|
| Node 16 | 6.0+                        | 93          |
| Node 15 | 5.0+                        | 88          |
| Node 14 | 4.14+                       | 83          |
| Node 13 | 4.13+, <5.0                 | 79          |
| Node 12 | 4.12+                       | 72          |
| Node 11 | 4.10+, <5.0                 | 67          |
| Node 10 | 4.9+, <6.0                  | 64          |
| Node 8  | 4.5.3+, <5.0                | 57          |
| Node <8 | <5.0                        | <57         |

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