README.md

Simple photo server

Simple photo server used by Android photo screensaver for TV.

The photo server takes a directory containing JPEG images and exposes two endpoints:

• /photos/list - returns a flat list of all photos found in the photos directory with their relative paths
• /photos - serves the files from the photos directory

The photo screensaver loads the list of photos from /photos/list and then displays a random photo by loading it from /photos/{PHOTO_RELATIVE_PATH}.

How to build

The photo server is compiled to a native image with GraalVM. To build the native image you need to set JAVA_HOME to the GraalVM distribution and install the required prerequisites:

SET "JAVA_HOME=<path-to-graalvm-jdk-21>"
mvn package -Pnative

Building and running a native image with Docker

Build the container image:

docker build -t photo-server .

Run the image:

docker run -d \
-p 40003:40003/tcp \
-p 5353:5353/udp \
--name=photo-server \
photo-server

The photo-server docker image exposes TCP port 40003 for the web server and UDP port 5353 for registering the photo-server service with mDNS-SD. Usually port 5353 will already be bound by another process on the host machine, so either remove the port binding (service discovery will not work) or run the container using the host network mode:

docker run -d \
--net=host \
--name=photo-server \
photo-server \
-p 40003

The photo-server image contains a default photos directory. To specify a photos directory from the host, you should mount it to /photos:

docker run -d \
-p 40003:40003/tcp \
--mount type=bind,source=<PATH_TO_PHOTOS_DIR>,target=/photos \
--name=photo-server \
photo-server

Building a native image and running as a service on Windows

You can also build a native executable and wrap it as a Windows service:

SET "JAVA_HOME=<path-to-graalvm-jdk-21>"
mvn package -Ddist-native

On Windows, this will build a native win32 executable and package it with Windows Service Wrapper.