How to fix diesel_cli link libpq.lib error with Postgres tools installed in Docker? - postgresql

Question

I'm trying (for hours now) to install the cargo crate diesel_cli for postgres. However, every time I run the recommended cargo command:
cargo install diesel_cli --no-default-features --features postgres
I wait a few minutes just to see the same build fail with this message:
note: LINK : fatal error LNK1181: cannot open input file 'libpq.lib'
error: aborting due to previous error
error: failed to compile `diesel_cli v1.4.1`, intermediate artifacts can be found at `C:\Users\<user name here>\AppData\Local\Temp\cargo-installUU2DtT`
Caused by:
could not compile `diesel_cli`.
I'm running postgres in a docker container and have the binaries on my C:\pgsql with the lib and bin directories both on the PATH so I can't figure out why it's not linking. What else could be required they didn't mention in the docs?

Answer 1

In my case the installation was successful but when I tried to run it this error occured.
maybe this would work for others who have the same problem:
open PowerShell
type in setx PQ_LIB_DIR "C:\Program Files\PostgreSQL\13\lib" (or any other path to your PostgreSQL lib)
restart your PC
run again
I had the same issue with WSL, if you're on Linux probably you could find PostgreSQL lib location and add it to your environment variables.

Answer 2

Update:
The answer below is a work around for older versions. Please check the possibility to execute cargo clean first
Original Version
Adding the folder to the PATH variable didn't help, at least in my case, as by some reason it is not used in the /LIBPATH parameter passed to link.exe.
In my case it was C:\Users\<username>\.rustup\toolchains\stable-x86_64-pc-windows-msvc\lib\rustlib\x86_64-pc-windows-msvc\lib
You can see it in the beginning of the error message.
Copy libpq.lib in there and it will be used from there.
After installation diesel would require some other assemblies. Copy libcrypto-1_1-x64.dll, libiconv-2.dll and libssl-1_1-x64.dll into the folder showed after where diesel command execution

Answer 3

I had the same error on Ubuntu and for me the following install fixed the issue:
sudo apt install libpq-dev

Answer 4

No need to move files around, just add C:\Program Files\PostgreSQL\14\lib and C:\Program Files\PostgreSQL\14\bin to your PATH. Installing and running diesel should have no problems.
Note: your paths may be different, and remember to close/reopen your terminal so the PATH variable is updated.
(Tested on Windows 10)

Answer 5

To give clear steps for windows:
Add C:\Users<username>.rustup\toolchains\stable-x86_64-pc-windows-msvc\lib\rustlib\x86_64-pc-windows-msvc\lib in the path in environment variables
Copy libpq.lib that is in C:\Program Files\PostgreSQL\14\lib (obviously this is with version 14) and paste it in C:\Users<username>.rustup\toolchains\stable-x86_64-pc-windows-msvc\lib\rustlib\x86_64-pc-windows-msvc\lib

Answer 6

If you've attempted to cargo build (or anything that runs the build scripts for libpq rust crate) when your environment was invalid, then you need to do a cargo clean after fixing your environment otherwise you'll still get the libpq.lib not found error even when it's in your PATH. The other answers where you copy the file into another directory are just hacks

Answer 7

You can instead add the path to .../lib to the compilers' library search paths, using RUSTFLAGS environment variable. It works both for installing diesel_cli and for building your projects.
RUSTFLAGS='-L /usr/local/pgsql/lib' cargo build
On Windows with EDB installer, the path contains a space, so use CARGO_ENCODED_RUSTFLAGS instead. For PowerShell:
$env:CARGO_ENCODED_RUSTFLAGS = "-L`u{1f}C:\Program Files\PostgreSQL\14\lib"