Add example of creating a new module (filter.py) with in a custom derived Docker

Author: kspaceKelvin

custom/custom.dockerfile

@@ -0,0 +1,28 @@
+# ----- 1. First stage to create a devcontainer -----
+# Start from standard python-ismrmrd-server devcontainer
+FROM kspacekelvin/fire-python-devcon AS fire-python-custom-devcon
+
+# Clone the latest version of python-ismrmrd-server
+RUN cd /opt/code && \
+    git clone https://github.com/kspaceKelvin/python-ismrmrd-server.git
+
+# Install any additional package dependencies here
+RUN pip install scipy
+
+# ----- 2. Second stage to create a runtime container for deployment -----
+FROM fire-python-custom-devcon AS fire-python-custom-runtime
+
+# Copy in modules and other files as needed
+COPY filter.py    /opt/code/python-ismrmrd-server
+COPY filter.json  /opt/code/python-ismrmrd-server
+
+# Set the starting directory so that code can use relative paths
+WORKDIR /opt/code/python-ismrmrd-server
+
+# Use the -d argument at the end to indicate the default (intended) module to be run by this Docker image
+CMD [ "python3", "/opt/code/python-ismrmrd-server/main.py", "-v", "-H=0.0.0.0", "-p=9002", "-l=/tmp/python-ismrmrd-server.log", "-d=filter"]
+
+# Replace the above CMD with this ENTRYPOINT to allow allow "docker stop"
+# commands to be passed to the server.  This is useful for deployments, but
+# more annoying for development
+# ENTRYPOINT [ "python3", "/opt/code/python-ismrmrd-server/main.py", "-v", "-H=0.0.0.0", "-p=9002", "-l=/tmp/python-ismrmrd-server.log", "-d=filter"]

custom/filter.json

@@ -0,0 +1,8 @@
+{
+    "version": "1.1.0",
+    "parameters": {
+        "options": "",
+        "filterSize": "3",
+        "sendOriginal": "True"
+    }
+}