MongoDB GridFS Component

Table of Contents

URI format
MongoDB GridFS options
Configuration of database in Spring XML
GridFS operations - producer endpoint

Available as of Camel 2.17

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

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

URI format

gridfs:connectionBean?database=databaseName&bucket=bucketName[&moreOptions...]

MongoDB GridFS options

The MongoDBGridFS component has no options.

The MongoDBGridFS component supports 18 endpoint options which are listed below:

{% raw %}

Name	Group	Default	Java Type	Description
connectionBean	common		`String`	Required Name of com.mongodb.Mongo to use.
bucket	common	`fs`	`String`	Sets the name of the GridFS bucket within the database. Default is fs.
database	common		`String`	Required Sets the name of the MongoDB database to target
readPreference	common		`ReadPreference`	Sets a MongoDB ReadPreference on the Mongo connection. Read preferences set directly on the connection will be overridden by this setting. The link com.mongodb.ReadPreferencevalueOf(String) utility method is used to resolve the passed readPreference value. Some examples for the possible values are nearest primary or secondary etc.
writeConcern	common		`WriteConcern`	Set the WriteConcern for write operations on MongoDB using the standard ones. Resolved from the fields of the WriteConcern class by calling the link WriteConcernvalueOf(String) method.
writeConcernRef	common		`WriteConcern`	Set the WriteConcern for write operations on MongoDB passing in the bean ref to a custom WriteConcern which exists in the Registry. You can also use standard WriteConcerns by passing in their key. See the link setWriteConcern(String) setWriteConcern method.
bridgeErrorHandler	consumer	`false`	`boolean`	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/ERROR level and ignored.
delay	consumer	`500`	`long`	Sets the delay between polls within the Consumer. Default is 500ms
fileAttributeName	consumer	`camel-processed`	`String`	If the QueryType uses a FileAttribute this sets the name of the attribute that is used. Default is camel-processed.
initialDelay	consumer	`1000`	`long`	Sets the initialDelay before the consumer will start polling. Default is 1000ms
persistentTSCollection	consumer	`camel-timestamps`	`String`	If the QueryType uses a persistent timestamp this sets the name of the collection within the DB to store the timestamp.
persistentTSObject	consumer	`camel-timestamp`	`String`	If the QueryType uses a persistent timestamp this is the ID of the object in the collection to store the timestamp.
query	consumer		`String`	Additional query parameters (in JSON) that are used to configure the query used for finding files in the GridFsConsumer
queryStrategy	consumer	`TimeStamp`	`QueryStrategy`	Sets the QueryStrategy that is used for polling for new files. Default is Timestamp
exceptionHandler	consumer (advanced)		`ExceptionHandler`	To let the consumer use a custom ExceptionHandler. Notice if the option bridgeErrorHandler is enabled then this options is not in use. By default the consumer will deal with exceptions that will be logged at WARN/ERROR level and ignored.
exchangePattern	consumer (advanced)		`ExchangePattern`	Sets the exchange pattern when the consumer creates an exchange.
operation	producer		`String`	Sets the operation this endpoint will execute against GridRS.
synchronous	advanced	`false`	`boolean`	Sets whether synchronous processing should be strictly used or Camel is allowed to use asynchronous processing (if supported).

{% endraw %}

Configuration of database in Spring XML

Table of Contents

Sample route

The following Spring XML creates a bean defining the connection to a MongoDB instance.

<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
    <bean id="mongoBean" class="com.mongodb.Mongo">
        <constructor-arg name="host" value="${mongodb.host}" />
        <constructor-arg name="port" value="${mongodb.port}" />
    </bean>
</beans>

Sample route

The following route defined in Spring XML executes the operation findOne on a collection.

Get a file from GridFS

<route>
  <from uri="direct:start" />
  <!-- using bean 'mongoBean' defined above -->
  <to uri="gridfs:mongoBean?database=${mongodb.database}&amp;operation=findOne" />
  <to uri="direct:result" />
</route>

GridFS operations - producer endpoint

Table of Contents

count
listAll
findOne
create
remove
GridFS Consumer

count

Returns the total number of file in the collection, returning an Integer as the OUT message body.

// from("direct:count").to("gridfs?database=tickets&operation=count");
Integer result = template.requestBodyAndHeader("direct:count", "irrelevantBody");
assertTrue("Result is not of type Long", result instanceof Integer);

You can provide a filename header to provide a count of files matching that filename.

Map<String, Object> headers = new HashMap<String, Object>();
headers.put(Exchange.FILE_NAME, "filename.txt");
Integer count = template.requestBodyAndHeaders("direct:count", query, headers);

listAll

Returns a Reader that lists all the filenames and their IDs in a tab separated stream.

// from("direct:listAll").to("gridfs?database=tickets&operation=listAll");
Reader result = template.requestBodyAndHeader("direct:listAll", "irrelevantBody");

filename1.txt   1252314321
filename2.txt   2897651254

findOne

Finds a file in the GridFS system and sets the body to an InputStream of the content. Also provides the metadata has headers. It uses Exchange.FILE_NAME from the incoming headers to determine the file to find.

// from("direct:findOne").to("gridfs?database=tickets&operation=findOne");
Map<String, Object> headers = new HashMap<String, Object>();
headers.put(Exchange.FILE_NAME, "filename.txt");
InputStream result = template.requestBodyAndHeaders("direct:findOne", "irrelevantBody", headers);

create

Creates a new file in the GridFs database. It uses the Exchange.FILE_NAME from the incoming headers for the name and the body contents (as an InputStream) as the content.

// from("direct:create").to("gridfs?database=tickets&operation=create");
Map<String, Object> headers = new HashMap<String, Object>();
headers.put(Exchange.FILE_NAME, "filename.txt");
InputStream stream = ... the data for the file ...
template.requestBodyAndHeaders("direct:create", stream, headers);

remove

Removes a file from the GridFS database.

// from("direct:remove").to("gridfs?database=tickets&operation=remove");
Map<String, Object> headers = new HashMap<String, Object>();
headers.put(Exchange.FILE_NAME, "filename.txt");
template.requestBodyAndHeaders("direct:remove", "", headers);