Remove the LXD internal provider

Canonical have relicensed the LXD project to AGPLv3. This means that we can
no longer update the go LXD client without re-licensing GARM as AGPLv3. This
is not desirable or possible.

The existing code seems to be Apache 2.0 and all code that has already been
contributed seems to stay as Apache 2.0, but new contributions from Canonical
employees will be AGPLv3.

We cannot risc including AGPLv3 code now or in the future, so we will separate
the LXD provider into its own project which can be AGPLv3. GARM will simply
execute the external provider.

If the client code of LXD will ever be split from the main project and re-licensed
as Apache 2.0 or a compatible license, we will reconsider adding it back as a
native provider. Although in the long run, I believe external providers will
be the only option as they are easier to write, easier to maintain and safer to
ship (a bug in the provider does not crash GARM itself).

Signed-off-by: Gabriel Adrian Samfira <gsamfira@cloudbasesolutions.com>

test/integration/config/config.toml

@@ -25,30 +25,11 @@ passphrase = "${DB_PASSPHRASE}"
 
 [[provider]]
 name = "lxd_local"
-provider_type = "lxd"
+provider_type = "external"
 description = "Local LXD installation"
-[provider.lxd]
-  unix_socket_path = "/var/snap/lxd/common/lxd/unix.socket"
-  include_default_profile = false
-  instance_type = "container"
-  secure_boot = false
-  project_name = "default"
-  [provider.lxd.image_remotes]
-    [provider.lxd.image_remotes.ubuntu]
-        addr = "https://cloud-images.ubuntu.com/releases"
-        public = true
-        protocol = "simplestreams"
-        skip_verify = false
-    [provider.lxd.image_remotes.ubuntu_daily]
-        addr = "https://cloud-images.ubuntu.com/daily"
-        public = true
-        protocol = "simplestreams"
-        skip_verify = false
-    [provider.lxd.image_remotes.images]
-        addr = "https://images.linuxcontainers.org"
-        public = true
-        protocol = "simplestreams"
-        skip_verify = false
+  [provider.external]
+    provider_executable = "${LXD_PROVIDER_EXECUTABLE}"
+    config_file = "${LXD_PROVIDER_CONFIG}"
 
 [[provider]]
 name = "test_external"

test/integration/config/garm-provider-lxd.toml

@@ -0,0 +1,21 @@
+unix_socket_path = "/var/snap/lxd/common/lxd/unix.socket"
+include_default_profile = false
+instance_type = "container"
+secure_boot = false
+project_name = "default"
+[image_remotes]
+  [image_remotes.ubuntu]
+    addr = "https://cloud-images.ubuntu.com/releases"
+    public = true
+    protocol = "simplestreams"
+    skip_verify = false
+  [image_remotes.ubuntu_daily]
+    addr = "https://cloud-images.ubuntu.com/daily"
+    public = true
+    protocol = "simplestreams"
+    skip_verify = false
+  [image_remotes.images]
+    addr = "https://images.linuxcontainers.org"
+    public = true
+    protocol = "simplestreams"
+    skip_verify = false

test/integration/scripts/setup-garm.sh

@@ -6,6 +6,9 @@ BINARIES_DIR="$PWD/bin"
 CONTRIB_DIR="$PWD/contrib"
 CONFIG_DIR="$PWD/test/integration/config"
 CONFIG_DIR_PROV="$PWD/test/integration/provider"
+PROVIDER_BIN_DIR="/opt/garm/providers.d/lxd"
+LXD_PROVIDER_EXECUTABLE="$PROVIDER_BIN_DIR/garm-provider-lxd"
+LXD_PROVIDER_CONFIG="$CONFIG_DIR/garm-provider-lxd.toml"
 
 if [[ ! -f $BINARIES_DIR/garm ]] || [[ ! -f $BINARIES_DIR/garm-cli ]]; then
     echo "ERROR: Please build GARM binaries first"
@@ -43,6 +46,12 @@ export DB_PASSPHRASE="$(generate_secret)"
 # Group "adm" is the LXD daemon group as set by the "canonical/setup-lxd" GitHub action.
 sudo useradd --shell /usr/bin/false --system --groups adm --no-create-home garm
 
+sudo mkdir -p $PROVIDER_BIN_DIR
+git clone https://github.com/cloudbase/garm-provider-lxd ~/garm-provider-lxd
+pushd ~/garm-provider-lxd
+go build -o $PROVIDER_BIN_DIR/garm-provider-lxd
+popd
+
 sudo mkdir -p /etc/garm
 cat $CONFIG_DIR/config.toml | envsubst | sudo tee /etc/garm/config.toml
 sudo chown -R garm:garm /etc/garm