check env vars populated & use multiline for visibility

Author: abbaspour

netlify.toml

@@ -1,5 +1,11 @@
 [build]
     base = "01-Login"
-    command = "printf '{\"domain\":\"%s\", \"clientId\":\"%s\"}' \"${AUTH0_DOMAIN}\" \"${AUTH0_CLIENT_ID}\" > public/auth_config.json && cp index.html public"
+    command = """if [ -z "${AUTH0_DOMAIN}" ] || [ -z "${AUTH0_CLIENT_ID}" ]; then
+            echo "Error: One or both environment variables (AUTH0_DOMAIN, AUTH0_CLIENT_ID) are not set or are empty."
+            exit 1
+        fi
+        printf '{\"domain\":\"%s\", \"clientId\":\"%s\"}' "${AUTH0_DOMAIN}" "${AUTH0_CLIENT_ID}" > public/auth_config.json
+        cp index.html public
+    """
     publish = "public"