I'm also happy to consider that (1) environment variables for this are kind of gross and perhaps we should be using command-line arguments and/or (2) that they should be opt-out rather than opt-in (e.g. set a variable to 0 if you don't want that component installed, or the variable name has "DONT" in it or similar), I just think that the logic involved in that gets more awkward and it's simpler to say that an env var being set is a signal to do something rather than not do something.

This is my proposal as is but I'd like to make sure it smells OK too, so speak up if your nose is twitching.

Options are mutually exclusive, run install.py multiple times to install multiple components.

Is that intentional or just how it turned out? You can approach it like this:

if os.environ.get('NODE_INSTALL_HEADERS', True): header_files(action)
if os.environ.get('NODE_INSTALL_NODE', True): node_files(action)
if os.environ.get('NODE_INSTALL_NPM', True): npm_files(action)

os.environ.get('NODE_INSTALL_HEADERS', True) - is that "default to True"? What values of NODE_INSTALL_HEADERS will evaluate to True vs False in this case?

os.environ.get('NODE_INSTALL_HEADERS', True) - is that "default to True?

Yes.

What values of NODE_INSTALL_HEADERS will evaluate to true vs false in this case?

Empty strings are false, everything else is truthy.

Empty strings are false, everything else is truthy.

So using that logic, this:

    NODE_INSTALL_HEADERS_ONLY=1 $(PYTHON) tools/install.py install '$(TARNAME)' '/' 

would become:

    NODE_INSTALL_NODE="" NODE_INSTALL_NPM="" $(PYTHON) tools/install.py install '$(TARNAME)' '/' 

?

@rvagg Yes, and I don't like that 😢. Instead of saying, install only headers, we are saying don't install node and npm.

Another option:

$(PYTHON) tools/install.py install-headers

And:

$(PYTHON) tools/install.py install-headers install-node /path/to/node/
$(PYTHON) tools/install.py install-npm /path/to/npm/

Or brevity:

$(PYTHON) tools/install.py headers

And:

$(PYTHON) tools/install.py headers node /path/to/node/
$(PYTHON) tools/install.py npm /path/to/npm/

Where the default, everything, is:

$(PYTHON) tools/install.py install

Although, "uninstall" is a problem in that case. Perhaps:

$(PYTHON) tools/install.py install --include-node --include-npm --include-headers

And an inverse:

$(PYTHON) tools/install.py install --no-include-node --no-include-npm --no-include-headers

but tbh, they all kind of smell

How about

tools/install.py --install node,npm,headers
tools/install.py --uninstall node,npm,headers

@thefourtheye yeah, that's not bad, but it's a big departure from the existing API which uses fixed arguments:

• argv[1]: 'install' or 'uninstall' (cmd)
• argv[2]: prefix for destination (DESTDIR)
• argv[3]: prefix within destination (PREFIX)

I reckon there's >0 users in the wild that are relying on this script outside of make.

we could just add --components node,npm,headers that overrides the default of everything and works for both install and uninstall.

we could just add --components node,npm,headers ...

yeah, that SGTM.

If someone with better Python chops wants to code some of that up for me it'd be appreciated, otherwise I'll muddle through it when I have the time.

@rvagg @bnoordhuis I created #5741. PTAL

#5741 is now my preferred option, closing in favour of that one but discussion is still open around all of this.