protected String getApiId(String orgId, String apiId, String version) {
        return EsUtils.escape(orgId + ":" + apiId + ":" + version); //$NON-NLS-1$ //$NON-NLS-2$
    }
Generates a valid document ID for a api, used to index the api in ES.
@param orgId the organization id
@param apiId the api id
@param version the api version
@return a api id
gateway/engine/es/src/main/java/io/apiman/gateway/engine/es/EsRegistry.java