feat(runner): added runner dockerfile and entrypoint

runner/Dockerfile

@@ -0,0 +1,9 @@
+# docker run -e METADATA_URL=https://garm.garm-provider-test.t09.de/api/v1/metadata -e CALLBACK_URL=https://garm.garm-provider-test.t09.de/api/v1/callbacks -e GITHUB_URL=https://garm-provider-test.t09.de/ -e RUNNER_NAME="lala" -e BEARER_TOKEN="" test
+FROM code.forgejo.org/forgejo/runner:11
+
+USER root
+RUN apk add curl
+
+COPY ./entrypoint.sh /entrypoint.sh
+
+ENTRYPOINT [ "/entrypoint.sh" ]

runner/entrypoint.sh

@@ -0,0 +1,40 @@
+#!/bin/bash
+# SPDX-License-Identifier: MIT
+#
+RUNNER_HOME=${RUNNER_HOME:-/data}
+
+set -ex
+set -o pipefail
+
+if [ ! -d "${RUNNER_HOME}" ]; then
+  log.error "$RUNNER_HOME should be an emptyDir mount. Please fix the pod spec."
+  exit 1
+fi
+
+if [ -z "$METADATA_URL" ]; then
+    echo "no token is available and METADATA_URL is not set"
+    exit 1
+fi
+
+if [ -z "$CALLBACK_URL" ]; then
+    echo "CALLBACK_URL is not set"
+    exit 1
+fi
+
+# retrieve runner secret from garm
+RUNNER_SECRET=$(curl --retry 5 --retry-delay 5 --retry-connrefused --fail -v -X GET -H 'Accept: application/json' -H "Authorization: Bearer ${BEARER_TOKEN}" "${METADATA_URL}/runner-registration-token/")
+
+forgejo-runner \
+    register \
+    --no-interactive \
+    --token ${RUNNER_SECRET} \
+    --name ${RUNNER_NAME} \
+    --instance ${GITHUB_URL} \
+    --labels ubuntu-host:host
+
+forgejo-runner generate-config > config.yml;
+
+unset RUNNER_SECRET
+unset BEARER_TOKEN
+
+/bin/forgejo-runner --config config.yml daemon