name: ecrou
base: core26
version: "0.1.0"
summary: The strictly confined microVM runtime
description: |
  ecrou boots disposable Linux environments as one-shot microVMs on
  libkrun: it resolves an image reference, boots one VM per command
  with live stdio, propagates the exit code, and throws the machine
  away. Persistence crosses an explicit `-v/--volume` share or it does not
  happen.

  ## First run

  Connect the KVM interface (home and network connect on their own):

      sudo snap connect ecrou:kvm

  Then run a command in a microVM:

      ecrou run ubuntu -- uname -a

  ## Diagnostics

  `ecrou probe` reports what a run would find: KVM, libkrun, the
  cache directory.

  ## Configuration and cache

  - image cache: `~/snap/ecrou/common/cache/ecrou`

  The home interface does not cover dotfiles, so the XDG
  directories are redirected into the snap's common data area.
license: MIT
grade: stable
confinement: strict

platforms:
  amd64:
  arm64:
  riscv64:

apps:
  ecrou:
    command: bin/ecrou
    command-chain: [command-chain/ecrou-env]
    plugs:
      - home
      - network
      - kvm

parts:
  ecrou:
    plugin: rust
    source: .
    rust-channel: "1.98.1"
    rust-path: [crates/ecrou-cli]
    build-packages: [cmake, perl]
    override-build: |
      craftctl default
      # The home interface stops at dotfiles, so ~/.cache is
      # unreachable under strict confinement. Point the XDG cache
      # lookup (the dirs crate honors the variable) into the snap's
      # durable area, shared across refreshes.
      mkdir -p "$CRAFT_PART_INSTALL/command-chain"
      cat > "$CRAFT_PART_INSTALL/command-chain/ecrou-env" <<'EOF'
      #!/bin/sh
      XDG_CACHE_HOME="$SNAP_USER_COMMON/cache"
      export XDG_CACHE_HOME
      mkdir -p "$XDG_CACHE_HOME"
      exec "$@"
      EOF
      chmod 755 "$CRAFT_PART_INSTALL/command-chain/ecrou-env"

  libkrun:
    plugin: rust
    source: https://github.com/containers/libkrun
    source-type: git
    source-tag: v1.19.7
    source-depth: 1
    rust-channel: "1.98.1"
    override-build: |
      cargo build --release -p libkrun --features net
      install -Dm755 target/release/libkrun.so \
        "$CRAFT_PART_INSTALL/lib/libkrun.so.1.19.7"
      ln -s libkrun.so.1.19.7 "$CRAFT_PART_INSTALL/lib/libkrun.so.1"

  libkrunfw:
    plugin: nil
    # libkrunfw5 ships only in stonking universe today, not in any LTS
    # base, so the .deb comes straight from the Ubuntu archive — one
    # flavor per target arch. riscv64 lives on the ports archive
    # (archive.ubuntu.com carries amd64 and arm64 binaries only). The
    # library embeds its kernel and has no external symbols, so it
    # runs on the base's older glibc.
    build-packages: [curl]
    override-pull: |
      arch="$CRAFT_ARCH_BUILD_FOR"
      case "$arch" in
        amd64)
          digest="924cd545080aaf5da66740d12a51b7a5cbd9a5c0b502d21cbef9bc82bf1c8b6b"
          pool="https://archive.ubuntu.com/ubuntu/pool/universe/libk/libkrunfw" ;;
        arm64)
          digest="9570e82feac79fd41a6a9674cc02a9b2f09948ac30ad480d05fc73a957843e56"
          pool="https://archive.ubuntu.com/ubuntu/pool/universe/libk/libkrunfw" ;;
        riscv64)
          digest="1f8b52a00eafdf52d2295eeab7dd527736788ce4d3aa97aecc18e3f4b66f413f"
          pool="https://ports.ubuntu.com/ubuntu-ports/pool/universe/libk/libkrunfw" ;;
        *) echo "no libkrunfw5 .deb mapped for $arch" >&2; exit 1 ;;
      esac
      curl -fL -o libkrunfw5.deb "$pool/libkrunfw5_5.5.0+ds-1_${arch}.deb"
      echo "$digest  libkrunfw5.deb" | sha256sum -c
    override-build: |
      dpkg -x libkrunfw5.deb unpack
      install -Dm755 "unpack/usr/lib/${CRAFT_ARCH_TRIPLET_BUILD_FOR}/libkrunfw.so.5.5.0" \
        "$CRAFT_PART_INSTALL/lib/libkrunfw.so.5.5.0"
      ln -s libkrunfw.so.5.5.0 "$CRAFT_PART_INSTALL/lib/libkrunfw.so.5"