Add Write Permission Check

Fixes: #31

.github/integration-test/missing-permissions-test.sh

@@ -0,0 +1,16 @@
+#!/bin/bash -e
+
+BASE_OUTPUT_DIR=$PWD/.github/integration-test/missing-permissions-test
+mkdir "$BASE_OUTPUT_DIR"
+
+OUTPUT=$(docker run -v "$PWD"/.github/integration-test/measures/code-measure.json:/app/measure.json \
+      -v "$BASE_OUTPUT_DIR":/app/output:ro --network integration-test_testing-network -e FHIR_SERVER=http://fhir-server:8080/fhir \
+      -it fhir-data-evaluator)
+EXIT_CODE=$?
+
+if [ "$OUTPUT" = "Missing writing permissions on output directory" ] && [ $EXIT_CODE = 1 ]; then
+  echo "OK 👍: docker container exited with code 1 and with the correct error message"
+else
+  echo "Fail 😞: docker container did not exit with code 1 or with a different error message"
+  exit 1
+fi

.github/workflows/build.yml

@@ -142,6 +142,9 @@ jobs:
       - name: Run Integration Test for Unique Count with Components and with CSV
         run: .github/integration-test/evaluate-unique-count-with-components-to-csv.sh /${PWD}/.github/integration-test/measures/unique-count-with-components-measure.json
 
+      - name: Run Integration Test to check if it correctly exits when there are insufficient writing permissions
+        run: .github/integration-test/missing-permissions-test.sh
+
 
   push-image:
     needs:

docker/docker-entrypoint.sh

@@ -1,5 +1,10 @@
 #!/bin/bash -e
 
+if [ ! -w /app/output ]; then
+    echo "Missing writing permissions on output directory" >&2
+    exit 1
+fi
+
 today=$(date +"%Y-%m-%d_%H-%M-%S")
 measureName="$(jq -c --raw-output '.name' /app/measure.json)"
 outputDir="$today-$measureName"