Opposite of --ensure, and is --ensure still useful?

[gibfahn]

I was looking for a way to force node-gyp to re-download the headers even if the directory already exists in $npm_config_devdir/$node_version, and I found --ensure, which seems to do the opposite.

As I understand it, node-gyp doesn't download the headers unless the directory is missing, so --ensure is the default behaviour. Am I missing something? Is there a --always-redownload option (and should there be)?

Obviously as a workaround you can do this before the node-gyp rebuild or npm install:

node "$(npm config get prefix)"/lib/node_modules/npm/node_modules/node-gyp/bin/node-gyp.js remove $(node -p process.versions.node) 

[gibfahn]

Thinking about this further, if the --tarball option is passed, I think it makes sense to delete the header directory and recreate it.

Thoughts?

[bnoordhuis]

As I understand it, node-gyp doesn't download the headers unless the directory is missing, so --ensure is the default behaviour. Am I missing something?

That's correct. It's unconditionally set in lib/configure.js.

Is there a --always-redownload option (and should there be)?

I don't think so. What good would it do?

Thinking about this further, if the --tarball option is passed, I think it makes sense to delete the header directory and recreate it.

I suppose. It could piggyback on the remove command.

[gibfahn]

I don't think so. What good would it do?

I ran into this because we were testing v8.0.0-pre, and node-gyp didn't re-download the headers, which meant that we got lots of this error when the NODE_MODULE_VERSION was updated:

module.js:598
  return process.dlopen(module, path._makeLong(filename));
                 ^

Error: The module '/space/jenkins-local/workspace/ibm-node8-appmetrics/ARCH/x64/CC/gcc48/OS/linux/label/build/node-v8.0.0-linux-x64/lib/node_modules/appmetrics/appmetrics.node'
was compiled against a different Node.js version using
NODE_MODULE_VERSION 55. This version of Node.js requires
NODE_MODULE_VERSION 57. Please try re-compiling or re-installing

When running in CI I always want to redownload the headers.

If the "--tarball always reinstalls the headers" option is acceptable I'm happy with that.