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Chapter 106. Flatpack Component

Available as of Camel version 1.4

The Flatpack component supports fixed width and delimited file parsing via the FlatPack library.
Notice: This component only supports consuming from flatpack files to Object model. You can not (yet) write from Object model to flatpack format.

Maven users will need to add the following dependency to their pom.xml for this component:

<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-flatpack</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

106.1. URI format

flatpack:[delim|fixed]:flatPackConfig.pzmap.xml[?options]

Or for a delimited file handler with no configuration file just use

flatpack:someName[?options]

You can append query options to the URI in the following format, ?option=value&option=value&…

106.2. URI Options

The Flatpack component has no options.

The Flatpack endpoint is configured using URI syntax:

flatpack:type:resourceUri

with the following path and query parameters:

106.2.1. Path Parameters (2 parameters):

Name	Description	Default	Type
type	Whether to use fixed or delimiter	delim	FlatpackType
resourceUri	Required URL for loading the flatpack mapping file from classpath or file system		String

106.2.2. Query Parameters (25 parameters):

Name	Description	Default	Type
allowShortLines (common)	Allows for lines to be shorter than expected and ignores the extra characters	false	boolean
delimiter (common)	The default character delimiter for delimited files.	,	char
ignoreExtraColumns (common)	Allows for lines to be longer than expected and ignores the extra characters	false	boolean
ignoreFirstRecord (common)	Whether the first line is ignored for delimited files (for the column headers).	true	boolean
splitRows (common)	Sets the Component to send each row as a separate exchange once parsed	true	boolean
textQualifier (common)	The text qualifier for delimited files.		char
bridgeErrorHandler (consumer)	Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions, that will be logged at WARN or ERROR level and ignored.	false	boolean
sendEmptyMessageWhenIdle (consumer)	If the polling consumer did not poll any files, you can enable this option to send an empty message (no body) instead.	false	boolean
exceptionHandler (consumer)	To let the consumer use a custom ExceptionHandler. Notice if the option bridgeErrorHandler is enabled then this option is not in use. By default the consumer will deal with exceptions, that will be logged at WARN or ERROR level and ignored.		ExceptionHandler
exchangePattern (consumer)	Sets the exchange pattern when the consumer creates an exchange.		ExchangePattern
pollStrategy (consumer)	A pluggable org.apache.camel.PollingConsumerPollingStrategy allowing you to provide your custom implementation to control error handling usually occurred during the poll operation before an Exchange have been created and being routed in Camel.		PollingConsumerPoll Strategy
synchronous (advanced)	Sets whether synchronous processing should be strictly used, or Camel is allowed to use asynchronous processing (if supported).	false	boolean
backoffErrorThreshold (scheduler)	The number of subsequent error polls (failed due some error) that should happen before the backoffMultipler should kick-in.		int
backoffIdleThreshold (scheduler)	The number of subsequent idle polls that should happen before the backoffMultipler should kick-in.		int
backoffMultiplier (scheduler)	To let the scheduled polling consumer backoff if there has been a number of subsequent idles/errors in a row. The multiplier is then the number of polls that will be skipped before the next actual attempt is happening again. When this option is in use then backoffIdleThreshold and/or backoffErrorThreshold must also be configured.		int
delay (scheduler)	Milliseconds before the next poll. You can also specify time values using units, such as 60s (60 seconds), 5m30s (5 minutes and 30 seconds), and 1h (1 hour).	500	long
greedy (scheduler)	If greedy is enabled, then the ScheduledPollConsumer will run immediately again, if the previous run polled 1 or more messages.	false	boolean
initialDelay (scheduler)	Milliseconds before the first poll starts. You can also specify time values using units, such as 60s (60 seconds), 5m30s (5 minutes and 30 seconds), and 1h (1 hour).	1000	long
runLoggingLevel (scheduler)	The consumer logs a start/complete log line when it polls. This option allows you to configure the logging level for that.	TRACE	LoggingLevel
scheduledExecutorService (scheduler)	Allows for configuring a custom/shared thread pool to use for the consumer. By default each consumer has its own single threaded thread pool.		ScheduledExecutor Service
scheduler (scheduler)	To use a cron scheduler from either camel-spring or camel-quartz2 component	none	ScheduledPollConsumer Scheduler
schedulerProperties (scheduler)	To configure additional properties when using a custom scheduler or any of the Quartz2, Spring based scheduler.		Map
startScheduler (scheduler)	Whether the scheduler should be auto started.	true	boolean
timeUnit (scheduler)	Time unit for initialDelay and delay options.	MILLISECONDS	TimeUnit
useFixedDelay (scheduler)	Controls if fixed delay or fixed rate is used. See ScheduledExecutorService in JDK for details.	true	boolean

106.3. Spring Boot Auto-Configuration

The component supports 12 options, which are listed below.

Name	Description	Default	Type
camel.component.flatpack.enabled	Enable flatpack component	true	Boolean
camel.component.flatpack.resolve-property-placeholders	Whether the component should resolve property placeholders on itself when starting. Only properties which are of String type can use property placeholders.	true	Boolean
camel.dataformat.flatpack.allow-short-lines	Allows for lines to be shorter than expected and ignores the extra characters	false	Boolean
camel.dataformat.flatpack.content-type-header	Whether the data format should set the Content-Type header with the type from the data format if the data format is capable of doing so. For example application/xml for data formats marshalling to XML, or application/json for data formats marshalling to JSon etc.	false	Boolean
camel.dataformat.flatpack.definition	The flatpack pzmap configuration file. Can be omitted in simpler situations, but its preferred to use the pzmap.		String
camel.dataformat.flatpack.delimiter	The delimiter char (could be ; , or similar)	,	String
camel.dataformat.flatpack.enabled	Enable flatpack dataformat	true	Boolean
camel.dataformat.flatpack.fixed	Delimited or fixed. Is by default false = delimited	false	Boolean
camel.dataformat.flatpack.ignore-extra-columns	Allows for lines to be longer than expected and ignores the extra characters.	false	Boolean
camel.dataformat.flatpack.ignore-first-record	Whether the first line is ignored for delimited files (for the column headers). Is by default true.	true	Boolean
camel.dataformat.flatpack.parser-factory-ref	References to a custom parser factory to lookup in the registry		String
camel.dataformat.flatpack.text-qualifier	If the text is qualified with a character. Uses quote character by default.		String

106.4. Examples

flatpack:fixed:foo.pzmap.xml creates a fixed-width endpoint using the foo.pzmap.xml file configuration.
flatpack:delim:bar.pzmap.xml creates a delimited endpoint using the bar.pzmap.xml file configuration.
flatpack:foo creates a delimited endpoint called foo with no file configuration.

106.5. Message Headers

Camel will store the following headers on the IN message:

Header	Description
`camelFlatpackCounter`	The current row index. For `splitRows=false` the counter is the total number of rows.

106.6. Message Body

The component delivers the data in the IN message as a org.apache.camel.component.flatpack.DataSetList object that has converters for java.util.Map or java.util.List.
Usually you want the Map if you process one row at a time (splitRows=true). Use List for the entire content (splitRows=false), where each element in the list is a Map.
Each Map contains the key for the column name and its corresponding value.

For example to get the firstname from the sample below:

  Map row = exchange.getIn().getBody(Map.class);
  String firstName = row.get("FIRSTNAME");

However, you can also always get it as a List (even for splitRows=true). The same example:

  List data = exchange.getIn().getBody(List.class);
  Map row = (Map)data.get(0);
  String firstName = row.get("FIRSTNAME");

106.7. Header and Trailer records

The header and trailer notions in Flatpack are supported. However, you must use fixed record IDs:

header for the header record (must be lowercase)
trailer for the trailer record (must be lowercase)

The example below illustrates this fact that we have a header and a trailer. You can omit one or both of them if not needed.

    <RECORD id="header" startPosition="1" endPosition="3" indicator="HBT">
        <COLUMN name="INDICATOR" length="3"/>
        <COLUMN name="DATE" length="8"/>
    </RECORD>

    <COLUMN name="FIRSTNAME" length="35" />
    <COLUMN name="LASTNAME" length="35" />
    <COLUMN name="ADDRESS" length="100" />
    <COLUMN name="CITY" length="100" />
    <COLUMN name="STATE" length="2" />
    <COLUMN name="ZIP" length="5" />

    <RECORD id="trailer" startPosition="1" endPosition="3" indicator="FBT">
        <COLUMN name="INDICATOR" length="3"/>
        <COLUMN name="STATUS" length="7"/>
    </RECORD>

106.8. Using the endpoint

A common use case is sending a file to this endpoint for further processing in a separate route. For example:

  <camelContext xmlns="http://activemq.apache.org/camel/schema/spring">
    <route>
      <from uri="file://someDirectory"/>
      <to uri="flatpack:foo"/>
    </route>

    <route>
      <from uri="flatpack:foo"/>
      ...
    </route>
  </camelContext>

You can also convert the payload of each message created to a Map for easy Bean Integration

106.9. Flatpack DataFormat

The Flatpack component ships with the Flatpack data format that can be used to format between fixed width or delimited text messages to a List of rows as Map.

marshal = from List<Map<String, Object>> to OutputStream (can be converted to String)
unmarshal = from java.io.InputStream (such as a File or String) to a java.util.List as an org.apache.camel.component.flatpack.DataSetList instance.
The result of the operation will contain all the data. If you need to process each row one by one you can split the exchange, using Splitter.

Notice: The Flatpack library does currently not support header and trailers for the marshal operation.

106.10. Options

The data format has the following options:

Option	Default	Description
`definition`	`null`	The flatpack pzmap configuration file. Can be omitted in simpler situations, but its preferred to use the pzmap.
`fixed`	`false`	Delimited or fixed.
`ignoreFirstRecord`	`true`	Whether the first line is ignored for delimited files (for the column headers).
`textQualifier`	`"`	If the text is qualified with a char such as `"`.
`delimiter`	`,`	The delimiter char (could be `;` `,` or similar)
`parserFactory`	`null`	Uses the default Flatpack parser factory.
`allowShortLines`	`false`	Camel 2.9.7 and 2.10.5 onwards: Allows for lines to be shorter than expected and ignores the extra characters.
`ignoreExtraColumns`	`false`	Camel 2.9.7 and 2.10.5 onwards: Allows for lines to be longer than expected and ignores the extra characters.

106.11. Usage

To use the data format, simply instantiate an instance and invoke the marshal or unmarshal operation in the route builder:

  FlatpackDataFormat fp = new FlatpackDataFormat();
  fp.setDefinition(new ClassPathResource("INVENTORY-Delimited.pzmap.xml"));
  ...
  from("file:order/in").unmarshal(df).to("seda:queue:neworder");

The sample above will read files from the order/in folder and unmarshal the input using the Flatpack configuration file INVENTORY-Delimited.pzmap.xml that configures the structure of the files. The result is a DataSetList object we store on the SEDA queue.

FlatpackDataFormat df = new FlatpackDataFormat();
df.setDefinition(new ClassPathResource("PEOPLE-FixedLength.pzmap.xml"));
df.setFixed(true);
df.setIgnoreFirstRecord(false);

from("seda:people").marshal(df).convertBodyTo(String.class).to("jms:queue:people");

In the code above we marshal the data from a Object representation as a List of rows as Maps. The rows as Map contains the column name as the key, and the corresponding value. This structure can be created in Java code from e.g. a processor. We marshal the data according to the Flatpack format and convert the result as a String object and store it on a JMS queue.

106.12. Dependencies

To use Flatpack in your camel routes you need to add the a dependency on camel-flatpack which implements this data format.

If you use maven you could just add the following to your pom.xml, substituting the version number for the latest & greatest release (see the download page for the latest versions).

<dependency>
  <groupId>org.apache.camel</groupId>
  <artifactId>camel-flatpack</artifactId>
  <version>x.x.x</version>
</dependency>

106.13. See Also

Configuring Camel
Component
Endpoint
Getting Started