Add nightly build action that uses Earthly. Another step in #1953

build/release/docker-nightly-earthly.sh

@@ -0,0 +1,13 @@
+#!/bin/sh
+
+# Docker build
+# Must authenticate first: https://docs.github.com/en/packages/using-github-packages-with-your-projects-ecosystem/configuring-docker-for-use-with-github-packages#authenticating-to-github-packages
+DOCKER_IMAGE="owncast-earthly"
+DATE=$(date +"%Y%m%d")
+VERSION="${DATE}-nightly"
+
+echo "Building Docker image ${DOCKER_IMAGE}..."
+
+earthly --ci --push +docker --image="ghcr.io/owncast/${DOCKER_IMAGE}" --tag=nightly --version=${VERSION}
+
+# docker push ghcr.io/owncast/${DOCKER_IMAGE}:nightly