nix-query-tree-viewer is a convenient way to visualize the output of
the dependencies of a given path in the Nix store.
This is the same tree information that nix-store --query --tree <PATH> outputs,
but nix-query-tree-viewer makes it easier to understand and interact with.
You can run nix-query-tree-viewer by passing it a path in the Nix store:
console
$ nix-query-tree-viewer /nix/store/ghzg4kg0sjif58smj2lfm2bdvjwim85y-gcc-wrapper-7.4.0
The command nix-store --query --tree can be used to see the dependencies of a
path in the Nix store in a tree format:
console
$ nix-store --query --tree /nix/store/ghzg4kg0sjif58smj2lfm2bdvjwim85y-gcc-wrapper-7.4.0
/nix/store/ghzg4kg0sjif58smj2lfm2bdvjwim85y-gcc-wrapper-7.4.0
+---/nix/store/681354n3k44r8z90m35hm8945vsp95h1-glibc-2.27
| +---/nix/store/681354n3k44r8z90m35hm8945vsp95h1-glibc-2.27 [...]
+---/nix/store/cinw572b38aln37glr0zb8lxwrgaffl4-bash-4.4-p23
| +---/nix/store/681354n3k44r8z90m35hm8945vsp95h1-glibc-2.27 [...]
| +---/nix/store/cinw572b38aln37glr0zb8lxwrgaffl4-bash-4.4-p23 [...]
+---/nix/store/hlnxw4k6931bachvg5sv0cyaissimswb-gcc-7.4.0-lib
| +---/nix/store/681354n3k44r8z90m35hm8945vsp95h1-glibc-2.27 [...]
| +---/nix/store/hlnxw4k6931bachvg5sv0cyaissimswb-gcc-7.4.0-lib [...]
+---/nix/store/f5wl80zkrd3fc1jxsljmnpn7y02lz6v1-glibc-2.27-bin
| +---/nix/store/681354n3k44r8z90m35hm8945vsp95h1-glibc-2.27 [...]
...
This is fine for simple derivations, but it gets very complicated for paths with deep dependency trees.
nix-query-tree-viewer helps with this by folding branches of the tree by
default. Clicking on a branch allows you to drill down into interesting
branches.
For example, here is the same picture as above, but with two of the branches open:
You can use nix-build and nix-instantiate to easily find the paths for
derivations.
For instance, if you want to find the path of gcc in the Nix store, you can
use nix-build:
console
$ nix-build '<nixpkgs>' -A gcc --no-out-link
...
/nix/store/ghzg4kg0sjif58smj2lfm2bdvjwim85y-gcc-wrapper-7.4.0
If you want to find the path of the .drv file for gcc, you can use
nix-instantiate:
console
$ nix-instantiate '<nixpkgs>' -A gcc
...
/nix/store/dyxdjxyszmlz29mb0jr9qkncj5l41dai-gcc-wrapper-7.4.0.drv
You should be able to pass both
/nix/store/ghzg4kg0sjif58smj2lfm2bdvjwim85y-gcc-wrapper-7.4.0 and
/nix/store/dyxdjxyszmlz29mb0jr9qkncj5l41dai-gcc-wrapper-7.4.0.drv to nix-query-tree-viewer.
In general, passing the output of nix-build to nix-query-tree-viewer will
let you see the run-time dependencies of a derivation, while passing the output
of nix-instantiate will let you see the build-time dependencies of a
derivation.
Feel free to open an issue or PR for any bugs/problems/suggestions/improvements.