Run WasmEdge container with Podman and crun on Fedora 36

podman_crun_wasmedge.md

How to run Wasm container with Podman and crun

Login to Fedora 36 Server

ssh fedoravm

Install prereq packages

container related packages (+ git, etc)

sudo dnf install git rpm-build crun podman buildah

Packages for WasmEdge build

sudo dnf install cmake clang lld llvm-devel lld-devel

Build and install WasmEdge

mkdir work
cd work
git clone https://github.com/WasmEdge/WasmEdge.git
cd WasmEdge/
mkdir build
cd build
cmake -DCMAKE_INSTALL_PREFIX=${HOME}/.wasmedge -DCMAKE_BUILD_TYPE=Release -DWASMEDGE_BUILD_TESTS=ON .. && make -j
make install
ln -s ~/.wasmedge/lib64/libwasmedge.so  ~/.wasmedge/lib64/libwasmedge_c.so

Build and install crun with WasmEdge support

Rebuild crun from source rpm.

cd ~
dnf download --source crun
rpm -ivh crun-1.5-1.fc36.src.rpm
cd ~/rpmbuild/
sudo dnf builddep SPECS/crun.spec
rpmbuild -bp SPECS/crun.spec
cd BUILD/crun-1.5/
./autogen.sh
CPPFLAGS=-I${HOME}/.wasmedge/include LDFLAGS="-Wl,-R${HOME}/.wasmedge/lib64 -L${HOME}/.wasmedge/lib64" ./configure --prefix=${HOME}/.crun --with-wasmedge
make -j
make install

Make sure the crun has WasmEdge support

Check if crun --version includes +WASM:wasmedge.

$ ~/.crun/bin/crun --version
crun version 1.5.0.0.0.41-ce75
commit: b6c3139229b6e62292fea63e3334dafc053bd4bc
spec: 1.0.0
+SYSTEMD +SELINUX +APPARMOR +CAP +SECCOMP +EBPF +CRIU +LIBKRUN +WASM:wasmedge +YAJL

Build Wasm binary

Prepare for Rust development environment

curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh
source ~/.cargo/env
rustup target add wasm32-wasi

Build sample Wasm code

cd ~/work
git clone https://github.com/second-state/wasm-learning.git
cd wasm-learning/cli/hello
cargo build --target wasm32-wasi

Run the Wasm binary as standalone

$ ~/.wasmedge/bin/wasmedge target/wasm32-wasi/debug/hello.wasm 
hello

Build container image from the Wasm binary

Create Dockerfile

cat > Dockerfile <<END
FROM scratch
COPY target/wasm32-wasi/debug/hello.wasm /
CMD ["/hello.wasm"]
END

Build Wasm container image

buildah build --annotation "module.wasm.image/variant=compat" -t mywasm-hello .

Run with Podman and crun

$ podman --runtime ~/.crun/bin/crun run localhost/mywasm-hello
hello