How to use

getSchemaFromConfig

method

in

com.hortonworks.streamline.common.util.Utils

private Schema getCustomProcessorInputSchema (Map config) throws IOException {
  return Utils.getSchemaFromConfig((Map) config.get(TopologyLayoutConstants.JSON_KEY_INPUT_SCHEMA));
}

/**
 * This method takes in a schema represented as a map and returns a {@link Schema}
 * @param schemaConfig A map representing {@link Schema}
 * @return schema generated from the map argument
 * @throws IOException
 */
public static Schema getSchemaFromConfig (Map schemaConfig) throws IOException {
  ObjectMapper objectMapper = new ObjectMapper();
  return getSchemaFromConfig(objectMapper.writeValueAsString(schemaConfig));
}
/**

private Map<String, Schema> getCustomProcessorOutputSchema (Map config) throws IOException {
  Map<String, Schema> result = new LinkedHashMap<>();
  Map<String, Object> outputSchemaConfig = (Map<String, Object>) config.get(TopologyLayoutConstants.JSON_KEY_OUTPUT_STREAMS_SCHEMA);
  for (Map.Entry<String, Object> entry: outputSchemaConfig.entrySet()) {
    result.put(entry.getKey(), Utils.getSchemaFromConfig((Map) entry.getValue()));
  }
  return result;
}

/**
 * Associate output schema that is a json string
 * @param outputSchemaJson
 * @return
 */
public CustomProcessorBolt outputSchema (String outputSchemaJson) {
  ObjectMapper mapper = new ObjectMapper();
  Map<String,Schema> outputSchema = new HashMap<>();
  try {
    Map<String, Map> output = mapper.readValue(outputSchemaJson, Map.class);
    for (Map.Entry<String, Map> entry: output.entrySet()) {
      outputSchema.put(entry.getKey(), Utils.getSchemaFromConfig(entry.getValue()));
    }
  } catch (IOException e) {
    LOG.error("Error during deserialization of output schema JSON string: {}", outputSchemaJson, e);
    throw new RuntimeException(e);
  }
  return outputSchema(outputSchema);
}

public static CustomProcessorInfo fromTopologyComponentBundle(TopologyComponentBundle topologyComponentBundle) throws IOException {
  Preconditions.checkNotNull(topologyComponentBundle, "topologyComponentBundle can not bre null");
  ComponentUISpecification topologyComponentUISpecification = topologyComponentBundle.getTopologyComponentUISpecification();
  List<ComponentUISpecification.UIField> uiFields = topologyComponentUISpecification.getFields();
  Map<String, String> config = getPropertiesFromUIFields(uiFields);
  return new CustomProcessorInfo(config.get(NAME),
      config.get(DESCRIPTION),
      topologyComponentBundle.getStreamingEngine(),
      config.get(JAR_FILE_NAME),
      config.get(CUSTOM_PROCESSOR_IMPL),
      Utils.getSchemaFromConfig(config.get(INPUT_SCHEMA)),
      Utils.getSchemaFromConfig(config.get(OUTPUT_SCHEMA)),
      getCustomProcessorUISpecification(topologyComponentUISpecification),
      config.get(DIGEST));
}

@Override
public void validateConfig () throws ComponentConfigException {
  super.validateConfig();
  validateStringFields();
  String fieldToValidate = TopologyLayoutConstants.JSON_KEY_OUTPUT_STREAMS_SCHEMA;
  try {
    Map<String, Map> outputSchema = (Map) conf.get(fieldToValidate);
    if (outputSchema == null || outputSchema.keySet().isEmpty()) {
      throw new ComponentConfigException(String.format(TopologyLayoutConstants.ERR_MSG_MISSING_INVALID_CONFIG, fieldToValidate));
    }
    for (Map.Entry<String, Map> entry: outputSchema.entrySet()) {
      Utils.getSchemaFromConfig(entry.getValue());
    }
    this.validateCustomConfigFields();
  } catch (ClassCastException|IOException e) {
    throw new ComponentConfigException(String.format(TopologyLayoutConstants.ERR_MSG_MISSING_INVALID_CONFIG, fieldToValidate));
  }
}