From caaa3a1dcdc15ae3fc9f097dcf262d9f0274e431 Mon Sep 17 00:00:00 2001
From: Vignesh Rao <svignesh1793@gmail.com>
Date: Mon, 9 Sep 2024 09:47:36 -0500
Subject: [PATCH] Add a feature to re-use existing configuration

---
 README.md          |  4 ++++
 docker-compose.yml |  1 +
 scripts/start.sh   | 18 +++++++++++++-----
 3 files changed, 18 insertions(+), 5 deletions(-)

diff --git a/README.md b/README.md
index 493c705..97c56b3 100644
--- a/README.md
+++ b/README.md
@@ -28,6 +28,10 @@ docker compose up -d
 - **RUNNER_NAME** - Runner name. Uses a random instance ID.
 - **WORK_DIR** - Work directory. Uses `_work`
 - **LABELS** - Runner labels (comma separated). Uses `"docker-node,${os_name}-${architecture}"`
+- **REUSE_EXISTING** - Re-use existing configuration. Defaults to `false`
+
+> `REUSE_EXISTING` can come in handy when a container restarts due to a problem,
+> or when a container is deleted without gracefully shutting down. 
 
 ## Development
 
diff --git a/docker-compose.yml b/docker-compose.yml
index 2e3d7a1..852a9d6 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -14,5 +14,6 @@ services:
       RUNNER_NAME: ${RUNNER_NAME}
       WORK_DIR: ${WORK_DIR}
       LABELS: ${LABELS}
+      REUSE_EXISTING: true
     container_name: github-runner-linux
     working_dir: /home/docker
diff --git a/scripts/start.sh b/scripts/start.sh
index b69ee0d..00248c3 100644
--- a/scripts/start.sh
+++ b/scripts/start.sh
@@ -24,6 +24,7 @@ RUNNER_NAME="${RUNNER_NAME:-"$(instance_id)"}"
 RUNNER_GROUP="${RUNNER_GROUP:-"default"}"
 WORK_DIR="${WORK_DIR:-"_work"}"
 LABELS="${LABELS:-"docker-node,$os_name-$architecture"}"
+REUSE_EXISTING="${REUSE_EXISTING:-"false"}"
 
 repo_level_runner() {
     # https://docs.github.com/en/rest/actions/self-hosted-runners#create-a-registration-token-for-a-repository
@@ -61,12 +62,19 @@ org_level_runner() {
         --url "https://github.com/${GIT_OWNER}"
 }
 
-if [ -n "${GIT_REPOSITORY}" ]; then
-    echo "Creating a repository level self-hosted runner ['${RUNNER_NAME}'] for ${GIT_REPOSITORY}"
-    repo_level_runner
+if [[ "$REUSE_EXISTING" == "true" || "$REUSE_EXISTING" == "1" ]] &&
+   [[ -d "/home/docker/actions-runner" ]] &&
+   [[ -f "/home/docker/actions-runner/config.sh" ]] &&
+   [[ -f "/home/docker/actions-runner/run.sh" ]]; then
+    echo "Existing configuration found. Re-using it..."
 else
-    echo "Creating an organization level self-hosted runner '${RUNNER_NAME}'"
-    org_level_runner
+  if [[ -n "$GIT_REPOSITORY" ]]; then
+      echo "Creating a repository level self-hosted runner ['${RUNNER_NAME}'] for ${GIT_REPOSITORY}"
+      repo_level_runner
+  else
+      echo "Creating an organization level self-hosted runner '${RUNNER_NAME}'"
+      org_level_runner
+  fi
 fi
 
 cleanup() {