remove symlink resolve and add force flag to copy cache operation

[hlolli]

this could be an darwin specific issue, but after the latest merge I'm unable to build (see my comment here #54 (comment)). But I did also experience the same issue as this PR #54 addresses and was able to make the cache copy operation happy. It seems it wants to copy directories into itself and that sorts of stuff.

[hlolli]

this change causes issues on linux 🤦

foo> npm ERR! code EXDEV
foo> npm ERR! syscall link
foo> npm ERR! path /build/source/npm-cache/_cacache/tmp/a2e9d406
foo> npm ERR! errno -18
foo> npm ERR! EXDEV: cross-device link not permitted, link '/build/source/npm-cache/_cacache/tmp/a2e9d406' -> '/build/source/npm-cache/_cacache/content-v2/sha512/94/fe/38e5fc939771f66dca9ee1c4205509b866f1f43703ae74d97f1a5317379b3797228c862642d98a6b91580bc5ab79a13a94cb558025138e3f79e2d9c0433d'
foo> 
foo> npm ERR! A complete log of this run can be found in:
foo> npm ERR!     /build/source/npm-cache/_logs/2022-09-23T12_56_25_222Z-debug-0.log
foo>

[hlolli]

that extra commit creates support for both linux and darwin, but I'd love to have another darwin user confirm this

[iensu]

Hi!

I was running in to another issue related to the npm-cache on darwin:

error: builder for '/nix/store/n21bw1ia9aivg0fq3d4mzf452w1040lg-foo-1.0.0.drv' failed with exit code 1;
       last 8 log lines:
       > unpacking sources
       > unpacking source archive /nix/store/6rivb57skw999c1qiwr54ch2v1jhmhhb-11sr8qcnqlchbrgvkdchzbm1ar7cig53-source
       > source root is 11sr8qcnqlchbrgvkdchzbm1ar7cig53-source
       > patching sources
       > configuring
       > cp: cannot create special file '/private/tmp/nix-build-foo-1.0.0.drv-0/11sr8qcnqlchbrgvkdchzbm1ar7cig53-source/npm-cache/_cacache/tmp/com.apple.launchd.jUMDGJPbBh/Listeners': Operation not permitted
       > cp: cannot create special file '/private/tmp/nix-build-foo-1.0.0.drv-0/11sr8qcnqlchbrgvkdchzbm1ar7cig53-source/npm-cache/_cacache/tmp/mongodb-27017.sock': Operation not permitted
       > cp: cannot copy a directory, '/nix/store/nfxfhqlckv4z3w93j5r3k69k6awv0q0g-foo-1.0.0-node-modules/npm-cache', into itself, '/private/tmp/nix-build-foo-1.0.0.drv-0/11sr8qcnqlchbrgvkdchzbm1ar7cig53-source/npm-cache'
       For full logs, run 'nix log /nix/store/n21bw1ia9aivg0fq3d4mzf452w1040lg-foo-1.0.0.drv'.

When trying out your fork @hlolli I managed to get a bit further in the process, but the build fails because I for some reason have root owned files in npm-cache? No idea why as of yet.

error: builder for '/nix/store/4sjiwiqnzsglwac6lxxi9jawdwzs19r5-foo-1.0.0.drv' failed with exit code 243;
       last 10 log lines:
       > npm ERR!
       > npm ERR! Your cache folder contains root-owned files, due to a bug in
       > npm ERR! previous versions of npm which has since been addressed.
       > npm ERR!
       > npm ERR! To permanently fix this problem, please run:
       > npm ERR!   sudo chown -R 501:20 "/nix/store/1wk888bpzy9m0k21b02qyhqakr2855as-foo-1.0.0-node-modules/npm-cache"
       >
       > npm ERR! Log files were not written due to an error writing to the directory: /nix/store/1wk888bpzy9m0k21b02qyhqakr2855as-foo-1.0.0-node-modules/npm-cache/_logs
       > npm ERR! You can rerun the command with `--loglevel=verbose` to see the logs in your terminal
       >
       For full logs, run 'nix log /nix/store/4sjiwiqnzsglwac6lxxi9jawdwzs19r5-foo-1.0.0.drv'.

[hlolli]

@iensu could it be related that you're running as nixbld user and not root? I keep seeing $whoami => root, which could explain why I don't see it. But in the case you're not root user while building, I guess we'll need chmod?