Various improvements

• Setup: adjust for OpenSearch v2
• ️ Services: add Certbot with auto SSL renewal
• ️ Update License information
• CI/CD: create pipeline
• Global: restructure files

closes #3 (closed)

.gitlab-ci/deploy.sh

+#!/bin/bash
+#
+# Deployment script for CRDM Logs.
+# Intended for execution by the GitLab Runner.
+
+set -euo pipefail
+
+# Ensure required environment variables are set.
+# DEPLOYMENT_HOST denotes the SSH TARGET. Can be only ONE IP or DNS name.
+if [ -z "$DEPLOYMENT_HOST" ]; then
+    echo "[ERROR] Make sure DEPLOYMENT_HOST is set." >&2
+    exit 1
+fi
+
+# ----------------------- #
+#    Repository checks    #
+# ----------------------- #
+DEPLOYMENT_PATH="${DEPLOYMENT_PATH:-crdm-logging-setup}"
+SSH_TARGET="${DEPLOYMENT_USER:-logs}@${DEPLOYMENT_HOST}"
+
+# SSH to target, initialize repo if it doesn't exist.
+# Otherwise, tear down old deployment and pull changes.
+ssh "${SSH_TARGET}" "bash" <<- EOF
+set -eu pipefail
+mkdir -p "${DEPLOYMENT_PATH}" && cd "${DEPLOYMENT_PATH}"
+
+if git status > /dev/null 2>&1; then
+    echo "[INFO] Pulling origin."
+    git pull "${CI_REPOSITORY_URL}"
+else
+    echo "[INFO] Git repository doesn't exist, cloning and setting up."
+    git clone "${CI_REPOSITORY_URL}" . > /dev/null 2>&1
+fi
+
+echo -n "[INFO] " && git checkout "${CI_COMMIT_BRANCH}"
+EOF
+
+# ----------------------- #
+#    .env file checks     #
+# ----------------------- #
+# Dump variables and transfer the file.
+echo "[INFO] Dumping variables to .env file."
+./scripts/dump-vars.sh ".env"
+scp ".env" "${SSH_TARGET}:${DEPLOYMENT_PATH}/.env"
+
+# SSH again, check if ssl directory is empty: setup or rerun.
+ssh "${SSH_TARGET}" "bash" <<- EOF
+set -eu pipefail
+cd "${DEPLOYMENT_PATH}"
+if [ $(find "./ssl" -type f ! -name '.gitkeep' | wc -l) -eq 0 ]; then
+    echo "[INFO] SSL directory only contains .gitkeep. Running setup.sh to create certificates."
+    ./scripts/setup.sh
+else
+    echo "[INFO] SSL directory is not empty. Skipping certificate setup."
+    docker compose up -d
+fi
+EOF