OpenSSL dependency for Rust

Help
1

I am trying to develop Rust applications on my NixOS machine. Poorly, when Emacs tries to check my project with Flycheck I get this error :

Error log 
--- stdout
cargo:rerun-if-env-changed=X86_64_UNKNOWN_LINUX_GNU_OPENSSL_LIB_DIR
cargo:rerun-if-env-changed=OPENSSL_LIB_DIR
cargo:rerun-if-env-changed=X86_64_UNKNOWN_LINUX_GNU_OPENSSL_INCLUDE_DIR
cargo:rerun-if-env-changed=OPENSSL_INCLUDE_DIR
cargo:rerun-if-env-changed=X86_64_UNKNOWN_LINUX_GNU_OPENSSL_DIR
cargo:rerun-if-env-changed=OPENSSL_DIR
run pkg_config fail: "`\"pkg-config\" \"--libs\" \"--cflags\" \"openssl\"` did not exit successfully: exit code: 1\n--- stderr\nPackage openssl was not found in the pkg-config search path.\nPerhaps you should add the directory containing `
openssl.pc\'\nto the PKG_CONFIG_PATH environment variable\nNo package \'openssl\' found\n"                                                                                                                                                    

--- stderr
thread 'main' panicked at '

Could not find directory of OpenSSL installation, and this `-sys` crate cannot
proceed without this knowledge. If OpenSSL is installed and this crate had
trouble finding it,  you can set the `OPENSSL_DIR` environment variable for the
compilation process.

Make sure you also have the development packages of openssl installed.
For example, `libssl-dev` on Ubuntu or `openssl-devel` on Fedora.

If you're in a situation where you think the directory *should* be found
automatically, please open a bug at https://github.com/sfackler/rust-openssl
and include information about your system as well as this message.

    $HOST = x86_64-unknown-linux-gnu
    $TARGET = x86_64-unknown-linux-gnu
    openssl-sys = 0.9.36

/openssl-sys-0.9.36/build/main.rs:265:9

And that even after installing the package globally openssl via nix-env. I also tried to set the environment variable to the relevant part of the nix store.
All of above without success.

Is there a way to solve the issue without creating a default.nix in each of my Rust project (read “a system-wide solution”) ?

Previous occurences

I did some search before asking about that issue both in the Rust and NixOS community and this is what I could gather :

  • this post seems to be closely related to my issue but I can not understand any answers in any of the pointed resources in the post. Are those solutions correct for a system-wide access to the library (openssl-dev) without having to open my editor through a nix-shell ?
  • this config file seems to solve (?) my issue but
    1. I have no idea if it is actually the case.
    2. I do not know how to implement it (e.g. where to put it, how to “call” it).
  • this part of the wiki seems to be related to my problem but deals with it in, what I can gather to be, a granular solution rather than a global one. Am I correct ? If yes, is it possible to generalize that solution for not a per-project basis but for the system itself ?

I understand from my last bullet point that I seem to be going “against the grain” of the NixOS philosophy but it seems cumbersome to not have a system-wide configuration (at least a default base) for when a program (here my text editor) is compiling a program outside of a nix-shell. Is it the case ? Did I miss a obvious part in the Nix manual ?

Sidenote : I found a bit sad that there is no relevant section in the wiki for that. So when I find a solution I will edit it.

1 Like
2

If all Rust projects are in some shared directory, e.g. ~/git/rust, you could place shell.nix in that directory. Though I personally just use a per-project shell.nix. I have a small nixify shell function that creates shell.nix.

You don’t have to. You can configure direnv to automatically use shell.nix if you cd into a directory:

In Emacs, I use the direnv package to automatically obtain the environment for the current file:

3

After some tests this week, it seems to be mostly working (maybe not to work on the compiler itself but it is a special snowflake) so I marked your answer as a solution (a sad one but a working one, thank you for that).

As stated in my original post, I then integrated my working solution in the relevant part of the wiki.

4

Thanks for documenting things in the wiki. You shouldn’t have to set OPENSSL_DIR/OPENSSL_LIB_DIR. The openssl-sys build script uses pkgconfig when it is available. So, it should be sufficient to add pkgconfig to your buildInputs,

5

Thank you for your contribution, will update the wiki in that regard. My Nix-fu is definitely not good. If you have suggestions, feel free to change the wiki !

6

If you want it to work with rust-anlyzer and vscode aswell, try this:
https://nixos.wiki/wiki/Visual_Studio_Code#Use_VS_Code_extensions_without_additional_configuration