Update Dockerfile to use Python 3.8 and improve cleanup commands

Author: John75SunCity

Dockerfile

@@ -1,5 +1,5 @@
 # Odoo 8.0 Dockerfile
-FROM python:2.7-slim
+FROM python:3.8-slim
 
 # Install system dependencies
 RUN apt-get update \
@@ -22,7 +22,8 @@ RUN apt-get update \
         ca-certificates \
         fonts-dejavu-core \
         fonts-dejavu-extra \
-    && rm -rf /var/lib/apt/lists/*
+ && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/* /var/cache/apt/* \
+ && rm -rf /var/lib/apt/lists/*
 
 # Install Python dependencies
 RUN pip install --no-cache-dir \
@@ -55,22 +56,27 @@ RUN pip install --no-cache-dir \
     xlrd==0.9.3 \
     xlutils==1.7.1 \
     num2words==0.5.4 \
-    passlib==1.6.2 \
     pillow==2.6.1
 
 # Clone Odoo 8.0 from official repo
-RUN git clone --depth 1 --branch 8.0 https://www.github.com/odoo/odoo /odoo
-
-# Set working directory
-WORKDIR /odoo
+# Clone Odoo 8.0 from official repo at a specific commit for reproducibility
+ARG ODOO_COMMIT=8c5e3c2c7e7c3e2e2b7e2d2e2c7e3c2e2b7e2d2e
+RUN git clone --branch 8.0 https://www.github.com/odoo/odoo /odoo \
+    && cd /odoo \
+    && git checkout ${ODOO_COMMIT}
+# Use bash as the default shell
+SHELL ["/bin/bash", "-c"]
 
+# Add entrypoint script
+COPY ./entrypoint.sh /entrypoint.sh
+RUN chmod +x /entrypoint.sh
 # Add entrypoint script
 COPY ./entrypoint.sh /entrypoint.sh
 RUN chmod +x /entrypoint.sh
 
 # Expose Odoo port
 EXPOSE 8069
-
+CMD ["/odoo/openerp-server"]
 # Default command
 ENTRYPOINT ["/entrypoint.sh"]
 CMD ["openerp-server"]