Update playwright-screenshots script to work under rootless podman

packages/element-web-playwright-common/playwright-screenshots.sh

@@ -1,5 +1,7 @@
 #!/bin/bash
 
+set -e
+
 # Handle symlinks here as we tend to be executed as an npm binary
 SCRIPT_PATH=$(readlink -f "$0")
 SCRIPT_DIR=$(dirname "$SCRIPT_PATH")
@@ -24,6 +26,20 @@ build_image() {
   docker build -t "$IMAGE_NAME" --build-arg "PLAYWRIGHT_VERSION=$PW_VERSION" "$SCRIPT_DIR"
 }
 
+# Find the docker socket on the host
+case "$DOCKER_HOST" in
+    unix://*)
+        docker_sock="${DOCKER_HOST:7}"
+        ;;
+    "")
+        docker_sock="/var/run/docker.sock"
+        ;;
+    *)
+        echo "$0: unsupported DOCKER_HOST setting '${DOCKER_HOST}'" >&2
+        exit 1;
+        ;;
+esac
+
 RUN_ARGS=(
   --rm
   --network host
@@ -33,7 +49,7 @@ RUN_ARGS=(
   # Bind mount the working directory into the container
   -v $(pwd):/work/
   # Bind mount the docker socket so we can run docker commands from the container
-  -v /var/run/docker.sock:/var/run/docker.sock
+  -v "${docker_sock}":/var/run/docker.sock
   # Bind mount /tmp so we can store temporary files
   -v /tmp/:/tmp/
   -it
@@ -69,15 +85,47 @@ done
 build_image
 
 # Ensure we pass all symlinked node_modules to the container
-pushd node_modules || exit > /dev/null
+pushd node_modules > /dev/null
 SYMLINKS=$(find . -maxdepth 2 -type l -not -path "./.bin/*")
-popd || exit > /dev/null
+popd > /dev/null
 for LINK in $SYMLINKS; do
-  TARGET=$(readlink -f "node_modules/$LINK")
+  TARGET=$(readlink -f "node_modules/$LINK") || true
   if [ -d "$TARGET" ]; then
+     if docker --version | grep -q podman; then
+        echo -e "\033[31m" >&2
+        cat <<'EOF' >&2
+WARNING: `node_modules` contains symlinks, and the support for this in
+`playwright-screenshots.sh` is broken under podman due to
+https://github.com/containers/podman/issues/25947.
+
+If you get errors such as 'Error: crun: creating `<path>`', then retry this
+having `yarn unlink`ed the relevant node modules.
+EOF
+      echo -e "\033[0m" >&2
+    fi
     echo "mounting linked package ${LINK:2} in container"
     RUN_ARGS+=( "-v" "$TARGET:/work/node_modules/${LINK:2}" )
   fi
 done
 
+# Our Playwright fixtures use Testcontainers [1], which in uses a docker image
+# called Ryuk [2], which will clean up any dangling containers/networks/etc
+# after a timeout, if the parent process dies unexpectedly.
+#
+# To do this, Ryuk requires access to the docker socket, so Testcontainers
+# starts the Ryuk container with a bind-mount of `/var/run/docker.sock`.
+# However, we're going to be running Playwright (and hence Testcontainers)
+# itself in a container, but talking to the Docker daemon on the *host*, which
+# means that bind mounts will be relative to the *host* filesystem. In short,
+# it will try to bind-mount the *host's* `/var/run/docker.sock` rather than
+# that from inside the element-web-playwright-common container.
+#
+# To solve this problem, we start Ryuk ourselves (with the correct docker
+# socket) rather than waiting for Testcontainers to do so. Testcontainers will
+# find the running Ryuk instance and connect to it rather than start a new one.
+#
+# [1] https://testcontainers.com/
+# [2] https://github.com/testcontainers/moby-ryuk
+docker run -d --rm --label org.testcontainers.ryuk=true -v "${docker_sock}":/var/run/docker.sock -p 8080 --name="playwright-ryuk" testcontainers/ryuk:0.14.0
+
 docker run "${RUN_ARGS[@]}" "$IMAGE_NAME" "${DEFAULT_ARGS[@]}" "$@"