automatically pull all custom container images on all nodes (#594)

Dockerfile

@@ -39,11 +39,14 @@ RUN ln -s /opt/pwn.college/etc/systemd/system/pwn.college.service /etc/systemd/s
     ln -s /opt/pwn.college/etc/systemd/system/pwn.college.backup.timer /etc/systemd/system/pwn.college.backup.timer && \
     ln -s /opt/pwn.college/etc/systemd/system/pwn.college.cachewarmer.service /etc/systemd/system/pwn.college.cachewarmer.service && \
     ln -s /opt/pwn.college/etc/systemd/system/pwn.college.cachewarmer.timer /etc/systemd/system/pwn.college.cachewarmer.timer && \
+    ln -s /opt/pwn.college/etc/systemd/system/pwn.college.imagepuller.service /etc/systemd/system/pwn.college.imagepuller.service && \
+    ln -s /opt/pwn.college/etc/systemd/system/pwn.college.imagepuller.timer /etc/systemd/system/pwn.college.imagepuller.timer && \
     ln -s /opt/pwn.college/etc/systemd/system/pwn.college.cloud.backup.service /etc/systemd/system/pwn.college.cloud.backup.service && \
     ln -s /opt/pwn.college/etc/systemd/system/pwn.college.cloud.backup.timer /etc/systemd/system/pwn.college.cloud.backup.timer && \
     ln -s /etc/systemd/system/pwn.college.service /etc/systemd/system/multi-user.target.wants/pwn.college.service && \
     ln -s /etc/systemd/system/pwn.college.backup.timer /etc/systemd/system/timers.target.wants/pwn.college.backup.timer && \
     ln -s /etc/systemd/system/pwn.college.cachewarmer.timer /etc/systemd/system/timers.target.wants/pwn.college.cachewarmer.timer && \
+    ln -s /etc/systemd/system/pwn.college.imagepuller.timer /etc/systemd/system/timers.target.wants/pwn.college.imagepuller.timer && \
     ln -s /etc/systemd/system/pwn.college.cloud.backup.timer /etc/systemd/system/timers.target.wants/pwn.college.cloud.backup.timer
 
 WORKDIR /opt/pwn.college

dojo/pull_images.sh

@@ -0,0 +1,3 @@
+#!/bin/sh
+
+dojo flask /opt/CTFd/CTFd/plugins/dojo_plugin/scripts/pull_images.py

dojo_plugin/scripts/pull_images.py

@@ -0,0 +1,21 @@
+import logging
+import docker
+import os
+
+from ..utils import all_docker_clients
+
+logger = logging.getLogger(__name__)
+logger.setLevel(logging.INFO)
+
+for image, in DojoChallenges.query.with_entities(db.distinct(DojoChallenges.data["image"])).all()
+	if not image or image.startswith("mac:") or image.startswith("pwncollege-"):
+		continue
+
+	for client in all_docker_clients():
+		logger.info(f"Pulling image {image} on {client.api.base_url}...")
+		try:
+			client.images.pull(image)
+		except docker.errors.ImageNotFound:
+			logger.error(f"... image not found: {image} on {client.api.base_url}...")
+		except Exception as e:
+			logger.error(f"... error: {image} on {client.api.base_url}...", exc_info=e)

etc/systemd/system/pwn.college.imagepuller.service

@@ -0,0 +1,7 @@
+[Unit]
+Description=Pull custom container images!
+
+[Service]
+Type=simple
+ExecStart=pull_images.sh
+ExecCondition=:/bin/sh -c '. /data/config.env; [ "${WORKSPACE_NODE}" -eq 0 ]'

etc/systemd/system/pwn.college.imagepuller.timer

@@ -0,0 +1,8 @@
+[Unit]
+Description=Timer to run pwn.college imagepuller service
+
+[Timer]
+OnCalendar=*-*-* *:*:00
+
+[Install]
+WantedBy=timers.target