update

.drone.yml

@@ -17,7 +17,11 @@ name: build
 steps:
   - name: publish
     image: plugins/kaniko
+    environment:
+      VERSION: 1.22.0
     settings:
+      build_args:
+        - VERSION=${VERSION}
       repo: docker.io/jcollie/healthchecks
       repository: docker.io
       username:
@@ -27,3 +31,4 @@ steps:
       tags:
         - latest
         - latest-${DRONE_BUILD_NUMBER}
+        - ${VERSION}-${DRONE_BUILD_NUMBER}

Dockerfile

@@ -1,10 +1,13 @@
 FROM python:3.9
 
+ARG VERSION
+
 ENV PYTHONUNBUFFERED=1
+
 WORKDIR /opt/healthchecks
 
 RUN useradd --system hc && \
-    git clone --depth 1 --branch v1.19.0 https://github.com/healthchecks/healthchecks.git /opt/healthchecks && \
+    git clone --depth 1 --branch v${VERSION} https://github.com/healthchecks/healthchecks.git /opt/healthchecks && \
     pip install --no-cache-dir -r /opt/healthchecks/requirements.txt && \
     pip install --no-cache-dir uwsgi && \
     rm -f /opt/healthchecks/hc/local_settings.py && \