Docker: verify output dirs are writable

docker/run.sh

@@ -32,11 +32,46 @@ OUTPUT_DIR_HTML="/root/arouteserver_html"
 
 if [[ ! -e "${OUTPUT_DIR}" && ! -d "${OUTPUT_DIR}" ]]; then
     error "The output directory ${OUTPUT_DIR} can't be found.
-          This is the directory where the configurations generate by ARouteServer will be saved.
+          This is the directory where the configurations generated by ARouteServer will be saved.
           Please be sure to mount the desired directory of the host to the ${OUTPUT_DIR} directory on the container.
           You can run the container passing the '-v PATH_OF_DIRECTORY_ON_THE_HOST:${OUTPUT_DIR}' argument."
 fi
 
+TEST_WRITABLE_FILE="${OUTPUT_DIR}/.test_dir_is_writable"
+
+set +e
+touch ${TEST_WRITABLE_FILE} &>/dev/null
+EXIT_CODE=$?
+set -e
+
+if [[ ${EXIT_CODE} -ne 0 ]]; then
+    error "It seems that the output directory ${OUTPUT_DIR} is not writable.
+          This is the directory where the configurations generated by ARouteServer will be saved.
+          Please be sure to mount the desired directory of the host to the ${OUTPUT_DIR} directory on the container.
+          You can run the container passing the '-v PATH_OF_DIRECTORY_ON_THE_HOST:${OUTPUT_DIR}' argument."
+fi
+
+rm ${TEST_WRITABLE_FILE} &>/dev/null
+
+if [[ -e "${OUTPUT_DIR_HTML}" && -d "${OUTPUT_DIR_HTML}" ]]; then
+
+    TEST_WRITABLE_FILE="${OUTPUT_DIR_HTML}/.test_dir_is_writable"
+
+    set +e
+    touch ${TEST_WRITABLE_FILE} &>/dev/null
+    EXIT_CODE=$?
+    set -e
+
+    if [[ ${EXIT_CODE} -ne 0 ]]; then
+        error "It seems that the HTML output directory ${OUTPUT_DIR_HTML} is not writable.
+              This is the directory where the textual representation of route server policy generated by ARouteServer will be saved.
+              Please be sure to mount the desired directory of the host to the ${OUTPUT_DIR_HTML} directory on the container.
+              You can run the container passing the '-v PATH_OF_DIRECTORY_ON_THE_HOST:${OUTPUT_DIR_HTML}' argument."
+    fi
+
+    rm ${TEST_WRITABLE_FILE} &>/dev/null
+fi
+
 if [[ -z "${DAEMON}" ]]; then
     error_envvar_not_set "DAEMON"
 fi