Ditch `cron` for `bash`

Dockerfile

@@ -8,7 +8,7 @@ EXPOSE 443
 # Do this apt/pip stuff all in one RUN command to avoid creating large
 # intermediate layers on non-squashable docker installs
 RUN apt update && \
-    apt install -y cron python python-dev libffi6 libffi-dev libssl-dev curl build-essential && \
+    apt install -y python python-dev libffi6 libffi-dev libssl-dev curl build-essential && \
     curl -L 'https://bootstrap.pypa.io/get-pip.py' | python && \
     pip install -U cffi certbot && \
     apt remove --purge -y python-dev build-essential libffi-dev libssl-dev curl && \
@@ -16,8 +16,7 @@ RUN apt update && \
     apt-get clean && \
     rm -rf /var/lib/apt/lists/*
 
-# Copy in cron job and scripts for certbot
-COPY ./crontab /etc/cron.d/certbot
+# Copy in scripts for certbot
 COPY ./scripts/ /scripts
 RUN chmod +x /scripts/*.sh
 

README.md

@@ -11,6 +11,9 @@ This repository was originally forked from `@henridwyer`, many thanks to him for
 
 # Changelog
 
+### 0.8
+- Ditch cron, it never liked me anway.  Just use `sleep` and a `while` loop instead.
+
 ### 0.7
 - Complete rewrite, build this image on top of the `nginx` image, and run `cron`/`certbot` alongside `nginx` so that we can have nginx configs dynamically enabled as we get SSL certificates.
 

crontab

@@ -1 +0,0 @@
-0 */12 * * * root sh /scripts/run_certbot.sh

scripts/entrypoint.sh

@@ -26,7 +26,15 @@ for f in /scripts/startup/*.sh; do
 done
 echo "Done with startup"
 
-# Run `cron -f &` so that it's a background job owned by bash and then `wait`.
-# This allows SIGINT (e.g. CTRL-C) to kill cron gracefully, due to our `trap`.
-cron -f &
-wait "$NGINX_PID"
+# Instead of trying to run `cron` or something like that, just leep and run `certbot`.
+while [ true ]; do
+    # Sleep for 1 week
+    sleep 604800 &
+    SLEEP_PID=$!
+
+    # re-run certbot
+    /scripts/run_certbot.sh
+
+    # Wait on sleep so that when we get ctrl-c'ed it kills everything due to our trap
+    wait "$SLEEP_PID"
+done