@Override
	public boolean checkRequireExpression(Requireable candidate, AppContextModel contextModel) {
		try {
			String requireExpression = candidate.getRequire();
			if (StringUtils.isBlank(requireExpression)) {
				return true;
			} else {
				// If any properties in contextModel are Maps, we want to allow scripts to access their subproperties
				// with dot notation, but ScriptEngine and Bindings don't naturally handle this. Instead we will convert
				// all Map-type properties to JSON and use this to define objects directly within the ScriptEngine.
				// (Properties that are not Maps don't need this special treatment.)
				Bindings bindings = new SimpleBindings();
				Map<String, Object> mapProperties = new HashMap<String, Object>();
				for (Map.Entry<String, Object> e : contextModel.entrySet()) {
					if (e.getValue() instanceof Map) {
						mapProperties.put(e.getKey(), e.getValue());
					} else {
						bindings.put(e.getKey(), e.getValue());
					}
				}

				ObjectMapper j = new ObjectMapper();
				for (Map.Entry<String, Object> e : contextModel.entrySet()) {
					if (!(e.getValue() instanceof Map) && !"util".equals(e.getKey())) {
						javascriptEngine.eval("var " + e.getKey() + " = " + j.writeValueAsString(e.getValue()) + ";");
					}
				}

				ObjectMapper jackson = new ObjectMapper();
				for (Map.Entry<String, Object> e : mapProperties.entrySet()) {
					try {
						javascriptEngine.eval("var " + e.getKey() + " = " + jackson.writeValueAsString(e.getValue()) + ";");
					} catch (Exception ex) {
						StringBuilder extraInfo = new StringBuilder();
						extraInfo.append("type:").append(e.getValue().getClass().getName());
						if (e.getValue() instanceof Map) {
							Map<?, ?> map = (Map<?, ?>) e.getValue();
							extraInfo.append(" properties:");
							for (Map.Entry entry : map.entrySet()) {
								extraInfo.append(" ").append(entry.getKey().toString()).append(":").append(entry.getValue() == null ? "null" : entry.getValue().getClass().toString());
							}
						}
						log.error("Failed to set '" + e.getKey() + "' scope variable (" + extraInfo + ") while evaluating require check for " + candidate.getClass().getSimpleName().toLowerCase() + " " + candidate.getId(), ex);
						return false;
					}
				}

				return javascriptEngine.eval("(" + requireExpression + ") == true").equals(Boolean.TRUE);
			}

		} catch (Exception e) {
			log.error("Failed to evaluate 'require' check for extension " + candidate.getId(), e);
			return false;
		}
	}