Reduce docker image size to between 1/5 and 2/5 of previous size. Correct readme docker notes. Remove redundant calls.

Dockerfile

@@ -3,23 +3,18 @@ FROM python:3.7-slim-buster
 COPY entrypoint /entrypoint
 
 RUN useradd -u 54000 radio && \
-    apt update && \
-    apt install -y git && \
-    cd /usr/src/ && \
-    git clone https://github.com/hacknix/dmr_utils && \
-    cd /usr/src/dmr_utils && \
-    ./install.sh && \
-    rm -rf /var/lib/apt/lists/* && \
-    cd /opt && \
-    rm -rf /usr/src/dmr_utils && \
-    git clone https://github.com/hacknix/freedmr && \
-    cd /opt/freedmr/ && \
-    sed -i s/.*python.*//g  requirements.txt && \
-    pip install --no-cache-dir -r requirements.txt && \
-    chown radio /opt/freedmr
-
-USER radio 
+        apt update && \
+        apt install -y git gcc && \
+        cd /opt && \
+        git clone https://github.com/hacknix/freedmr && \
+        cd freedmr && \
+        pip install --no-cache-dir -r requirements.txt && \
+        apt autoremove -y git gcc && \
+        rm -rf /var/lib/apt/lists/* && \
+        chown -R radio: /opt/freedmr
 
 EXPOSE 54000
 
+USER radio
+
 ENTRYPOINT [ "/entrypoint" ]

README.md

@@ -39,17 +39,23 @@ This document assumes the reader is familiar with Linux/UNIX, the Python program
 
 **Using the docker version**
 
-Build the docker image
+Build the docker image.
 
 ```bash
 docker build --tag freedmr .
 ```
 
-Start your container
+Start your container, passing your configuration file.
 
 ```bash
 cfg_file="/absolute/path/to/cfg/file"
-run -v $cfg_file:/opt/freedmr/hblink.cfg -p 54000:54000 freedmr
+docker run -v $cfg_file:/opt/freedmr/hblink.cfg -p 54000:54000 freedmr
+```
+
+Note that `$cfg_file` is used by the container's 'radio' user internally, so you may need to modify file permissions.
+
+```bash
+chmod 666 $cfg_file
 ```
 
 **MORE DOCUMENTATION TO COME**