feat: use chown during copy to reduce image size and build time

Using the `--chown` flag during `COPY` is much faster than running
`chown -R`. It also removes a layer from the image, resulting in faster
and smaller builds.

Resolves #55

Signed-off-by: Lucas Roesler <roesler.lucas@gmail.com>

Author: LucasRoesler

.gitignore

@@ -0,0 +1 @@
+build

template/python27-flask/Dockerfile

@@ -18,23 +18,22 @@ ENV PATH=$PATH:/home/app/.local/bin
 
 WORKDIR /home/app/
 
-COPY index.py           .
-COPY requirements.txt   .
+COPY --chown=app:app index.py           .
+COPY --chown=app:app requirements.txt   .
 USER root
 RUN pip install -r requirements.txt
 USER app
 
 RUN mkdir -p function
 RUN touch ./function/__init__.py
 WORKDIR /home/app/function/
-COPY function/requirements.txt	.
+COPY --chown=app:app function/requirements.txt	.
 RUN pip install --user -r requirements.txt
 
 WORKDIR /home/app/
 
 USER root
-COPY function   function
-RUN chown -R app:app ./
+COPY --chown=app:app function   function
 USER app
 
 ENV fprocess="python index.py"

template/python3-flask-debian/Dockerfile

@@ -19,8 +19,8 @@ ENV PATH=$PATH:/home/app/.local/bin
 
 WORKDIR /home/app/
 
-COPY index.py           .
-COPY requirements.txt   .
+COPY --chown=app:app index.py           .
+COPY --chown=app:app requirements.txt   .
 
 USER root
 RUN pip install -r requirements.txt
@@ -31,14 +31,13 @@ USER app
 RUN mkdir -p function
 RUN touch ./function/__init__.py
 WORKDIR /home/app/function/
-COPY function/requirements.txt	.
+COPY --chown=app:app function/requirements.txt	.
 RUN pip install --user -r requirements.txt
 
 #install function code
 USER root
 
-COPY function/   .
-RUN chown -R app:app ../
+COPY --chown=app:app function/   .
 
 ARG TEST_COMMAND=tox
 ARG TEST_ENABLED=true

template/python3-flask/Dockerfile

@@ -19,8 +19,8 @@ ENV PATH=$PATH:/home/app/.local/bin
 
 WORKDIR /home/app/
 
-COPY index.py           .
-COPY requirements.txt   .
+COPY --chown=app:app index.py           .
+COPY --chown=app:app requirements.txt   .
 
 USER root
 RUN pip install -r requirements.txt
@@ -31,14 +31,13 @@ USER app
 RUN mkdir -p function
 RUN touch ./function/__init__.py
 WORKDIR /home/app/function/
-COPY function/requirements.txt	.
+COPY --chown=app:app function/requirements.txt	.
 RUN pip install --user -r requirements.txt
 
 #install function code
 USER root
 
-COPY function/   .
-RUN chown -R app:app ../
+COPY --chown=app:app function/   .
 
 ARG TEST_COMMAND=tox
 ARG TEST_ENABLED=true

template/python3-http-debian/Dockerfile

@@ -19,21 +19,20 @@ ENV PATH=$PATH:/home/app/.local/bin
 
 WORKDIR /home/app/
 
-COPY index.py           .
-COPY requirements.txt   .
+COPY --chown=app:app index.py           .
+COPY --chown=app:app requirements.txt   .
 USER root
 RUN pip install -r requirements.txt
 USER app
 
 RUN mkdir -p function
 RUN touch ./function/__init__.py
 WORKDIR /home/app/function/
-COPY function/requirements.txt	.
+COPY --chown=app:app function/requirements.txt	.
 RUN pip install --user -r requirements.txt
 
 USER root
-COPY function/   .
-RUN chown -R app:app ../
+COPY --chown=app:app function/   .
 
 ARG TEST_COMMAND=tox
 ARG TEST_ENABLED=true

template/python3-http/Dockerfile

@@ -19,8 +19,8 @@ ENV PATH=$PATH:/home/app/.local/bin
 
 WORKDIR /home/app/
 
-COPY index.py           .
-COPY requirements.txt   .
+COPY --chown=app:app index.py           .
+COPY --chown=app:app requirements.txt   .
 USER root
 RUN pip install -r requirements.txt
 
@@ -30,13 +30,12 @@ USER app
 RUN mkdir -p function
 RUN touch ./function/__init__.py
 WORKDIR /home/app/function/
-COPY function/requirements.txt	.
+COPY --chown=app:app function/requirements.txt	.
 RUN pip install --user -r requirements.txt
 
 # install function code
 USER root
-COPY function/   .
-RUN chown -R app:app ../
+COPY --chown=app:app function/   .
 
 ARG TEST_COMMAND=tox
 ARG TEST_ENABLED=true