[dockerfiles] Use docker buildkit caching in dockerfiles

dockerfiles/Dockerfile

@@ -1,28 +1,30 @@
+# syntax = docker/dockerfile:1.2
 FROM phusion/baseimage:focal-1.0.0
 
 RUN adduser --disabled-password --gecos "" app_user
+RUN echo "alias python=python3" > /home/app_user/.bashrc
 
 RUN apt-get update && \
     apt-get -y install software-properties-common \
-    python3-dev \
-    python3-pip
+                       python3-dev \
+                       python3-pip && \
+    apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
 
-RUN pip3 install --upgrade pip
+RUN --mount=type=cache,target=/root/.cache/pip pip3 install --upgrade pip
 
 # Create src dir
 ENV PROJECT_DIR /py-pdf-parser
-
 WORKDIR $PROJECT_DIR
-ADD ./ $PROJECT_DIR
+
+# Add imagemagick policy
 ADD ./imagemagick_policy.xml /etc/ImageMagick-6/policy.xml
 
-# Clean up APT when done.
-RUN apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
+# Install requirements
+ADD ./setup.py $PROJECT_DIR/setup.py
+ADD ./README.md $PROJECT_DIR/README.md
+RUN --mount=type=cache,target=/root/.cache/pip pip3 install -e $PROJECT_DIR
 
+# Copy code, chown and switch user
+ADD ./ $PROJECT_DIR
 RUN chown -R app_user: $PROJECT_DIR
-
-RUN pip3 install $PROJECT_DIR
-
 USER app_user
-
-RUN echo "alias python=python3" > /home/app_user/.bashrc

dockerfiles/Dockerfile_dev

@@ -1,31 +1,33 @@
+# syntax = docker/dockerfile:1.2
 FROM phusion/baseimage:focal-1.0.0
 
 RUN adduser --disabled-password --gecos "" app_user
+RUN echo "alias python=python3" > /home/app_user/.bashrc
 
 RUN apt-get update && \
     apt-get -y install software-properties-common \
-    python3-dev \
-    python3-pip \
-    libmagickwand-dev \
-    mesa-utils \
-    libxkbcommon-x11-dev
+                       python3-dev \
+                       python3-pip \
+                       libmagickwand-dev \
+                       mesa-utils \
+                       libxkbcommon-x11-dev && \
+    apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
 
-RUN pip3 install --upgrade pip
+RUN --mount=type=cache,target=/root/.cache/pip pip3 install --upgrade pip
 
 # Create src dir
 ENV PROJECT_DIR /py-pdf-parser
-
 WORKDIR $PROJECT_DIR
-ADD ./ $PROJECT_DIR
+
+# Add imagemagick policy
 ADD ./imagemagick_policy.xml /etc/ImageMagick-6/policy.xml
 
-# Clean up APT when done.
-RUN apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
+# Install requirements
+ADD ./setup.py $PROJECT_DIR/setup.py
+ADD ./README.md $PROJECT_DIR/README.md
+RUN --mount=type=cache,target=/root/.cache/pip pip3 install -e $PROJECT_DIR[dev]
 
+# Copy code, chown and switch user
+ADD ./ $PROJECT_DIR
 RUN chown -R app_user: $PROJECT_DIR
-
-RUN pip3 install -e $PROJECT_DIR[dev]
-
 USER app_user
-
-RUN echo "alias python=python3" > /home/app_user/.bashrc

dockerfiles/Dockerfile_tests

@@ -1,35 +1,35 @@
+# syntax = docker/dockerfile:1.2
 FROM phusion/baseimage:focal-1.0.0
 
 RUN adduser --disabled-password --gecos "" app_user
+RUN echo "alias python=python3" > /home/app_user/.bashrc
 
 RUN apt-get update && \
     apt-get -y install software-properties-common \
-    python3-dev \
-    python3-pip \
-    libmagickwand-dev \
-    xvfb
+                       python3-dev \
+                       python3-pip \
+                       libmagickwand-dev \
+                       mesa-utils \
+                       libxkbcommon-x11-dev \
+                       xvfb && \
+    apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
 
-RUN pip3 install --upgrade pip
+RUN --mount=type=cache,target=/root/.cache/pip pip3 install --upgrade pip
 
 # Create src dir
 ENV PROJECT_DIR /py-pdf-parser
-
 WORKDIR $PROJECT_DIR
-COPY ./README.md $PROJECT_DIR/README.md
-COPY ./setup.py $PROJECT_DIR/setup.py
 
-# Clean up APT when done.
-RUN apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
-
-RUN chown -R app_user: $PROJECT_DIR
+# Add imagemagick policy
+ADD ./imagemagick_policy.xml /etc/ImageMagick-6/policy.xml
 
-RUN pip3 install -e $PROJECT_DIR[dev]
-RUN pip3 install -e $PROJECT_DIR[test]
+# Install requirements
+ADD ./setup.py $PROJECT_DIR/setup.py
+ADD ./README.md $PROJECT_DIR/README.md
+RUN --mount=type=cache,target=/root/.cache/pip pip3 install -e $PROJECT_DIR[dev]
+RUN --mount=type=cache,target=/root/.cache/pip pip3 install -e $PROJECT_DIR[test]
 
-COPY ./imagemagick_policy.xml /etc/ImageMagick-6/policy.xml
-COPY ./ $PROJECT_DIR
+# Copy code, chown and switch user
+ADD ./ $PROJECT_DIR
 RUN chown -R app_user: $PROJECT_DIR
-
 USER app_user
-
-RUN echo "alias python=python3" > /home/app_user/.bashrc