THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
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Maven users will need to add the following dependency to their pom.xml for this component:
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<dependency>
<groupId>org.apache.camel</groupId>
<artifactId>camel-hbase</artifactId>
<version>x.x.x</version>
<!-- use the same version as your Camel core version -->
</dependency>
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The HBase component can be provided a custom HBaseConfiguration object as a property or it can create an HBase configuration object on its own based on the HBase related resources that are found on classpath.
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<bean id="hbase" class="org.apache.camel.component.hbase.HBaseComponent">
<property name="configuration" ref="config"/>
</bean>
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As mentioned above camel provides produers endpoints for HBase. This allows you to store, delete, retrieve or query data from HBase using your camel routes.
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hbase://table[?options]
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where table is the table name.
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The simplest scenario for storing data into HBase from a camel route, would be to store part of the message body to specified HBase column.
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<route>
<from uri="direct:in"/>
<!-- Set the HBase Row -->
<setHeader headerName="CamelHBaseRowId">
<el>${in.body.id}</el>
</setHeader>
<!-- Set the HBase Value -->
<setHeader headerName="CamelHBaseValue">
<el>${in.body.value}</el>
</setHeader>
<to uri="hbase:mytable?opertaion=CamelHBasePut&family=myfamily&qualifier=myqualifier"/>
</route>
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The route above assumes that the message body contains an object that has an id and value property and will store the content of value in the HBase column myfamily:myqualifier in the row specified by id. If we needed to specify more than one column/value pairs we could just specify additional column mappings:. Notice that you must use numbers from the 2nd header onwards, eg RowId2, RowId3, RowId4, etc. Only the 1st header does not have the number 1.
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<route> <from uri="direct:in"/> <!-- Set the HBase Row 1st column --> <setHeader headerName="CamelHBaseRowId"> <el>${in.body.id}</el> </setHeader> <!-- Set the HBase Row 2nd column --> <setHeader headerName="CamelHBaseRowIdCamelHBaseRowId2"> <el>${in.body.id}</el> </setHeader> <!-- Set the HBase Value for 1st column --> <setHeader headerName="CamelHBaseValue"> <el>${in.body.value}</el> </setHeader> <!-- Set the HBase Value for 2nd column --> <setHeader headerName="CamelHBaseValue2"> <el>${in.body.othervalue}</el> </setHeader> <to uri="hbase:mytable?opertaion=CamelHBasePut&family=myfamily&qualifier=myqualifier&family2=myfamily&qualifier2=myqualifier2"/> </route> |
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A Get Operation is an operation that is used to retrieve one or more values from a specified HBase row. To specify what are the values that you want to retrieve you can just specify them as part of the uri or as message headers.
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<route>
<from uri="direct:in"/>
<!-- Set the HBase Row of the Get -->
<setHeader headerName="CamelHBaseRowId">
<el>${in.body.id}</el>
</setHeader>
<to uri="hbase:mytable?opertaion=CamelHBaseGet&family=myfamily&qualifier=myqualifier&valueType=java.lang.Long"/>
<to uri="log:out"/>
</route>
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You can also you camel-hbase to perform HBase delete operation. The delete operation will remove an entire row. All that needs to be specified is one or more rows as part of the message headers.
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<route>
<from uri="direct:in"/>
<!-- Set the HBase Row of the Get -->
<setHeader headerName="CamelHBaseRowId">
<el>${in.body.id}</el>
</setHeader>
<to uri="hbase:mytable?opertaion=CamelHBaseDelete"/>
</route>
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A scan operation is the equivalent of a query in HBase. You can use the scan operation to retrieve multiple rows. To specify what columns should be part of the result and also specify how the values will be converted to objects you can use either uri options or headers.
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<route>
<from uri="direct:in"/>
<to uri="hbase:mytable?opertaion=CamelHBaseScan&family=myfamily&qualifier=myqualifier&valueType=java.lang.Long&rowType=java.lang.String"/>
<to uri="log:out"/>
</route>
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For example to perform scan using as criteria the message headers, you can make use of the ModelAwareColumnMatchingFilter as shown below.
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<route>
<from uri="direct:scan"/>
<!-- Set the Criteria -->
<setHeader headerName="CamelHBaseFamily">
<constant>name</constant>
</setHeader>
<setHeader headerName="CamelHBaseQualifier">
<constant>first</constant>
</setHeader>
<setHeader headerName="CamelHBaseValue">
<el>in.body.firstName</el>
</setHeader>
<setHeader headerName="CamelHBaseFamily2">
<constant>name</constant>
</setHeader>
<setHeader headerName="CamelHBaseQualifier2">
<constant>last</constant>
</setHeader>
<setHeader headerName="CamelHBaseValue2">
<el>in.body.lastName</el>
</setHeader>
<!-- Set additional fields that you want to be return by skipping value -->
<setHeader headerName="CamelHBaseFamily3">
<constant>address</constant>
</setHeader>
<setHeader headerName="CamelHBaseQualifier3">
<constant>country</constant>
</setHeader>
<to uri="hbase:mytable?opertaion=CamelHBaseScan&filters=#myFilterList"/>
</route>
<bean id="myFilters" class="java.util.ArrayList">
<constructor-arg>
<list>
<bean class="org.apache.camel.component.hbase.filters.ModelAwareColumnMatchingFilter"/>
</list>
</constructor-arg>
</bean>
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The Camel HBase Consumer, will perform repeated scan on the specified HBase table and will return the scan results as part of the message. You can either specify header mapping (default) or body mapping. The later will just add the org.apache.camel.component.hbase.model.HBaseData as part of the message body.
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hbase://table[?options]
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You can specify the columns that you want to be return and their types as part of the uri options:
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hbase:mutable?family=name&qualifer=first&valueType=java.lang.String&family=address&qualifer=number&valueType2=java.lang.Integer&rowType=java.lang.Long
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The camel-hbase component also provides an idempotent repository which can be used when you want to make sure that each message is processed only once. The HBase idempotent repository is configured with a table, a column family and a column qualifier and will create to that table a row per message.
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HBaseConfiguration configuration = HBaseConfiguration.create();
HBaseIdempotentRepository repository = new HBaseIdempotentRepository(configuration, tableName, family, qualifier);
from("direct:in")
.idempotentConsumer(header("messageId"), repository)
.to("log:out);
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In order to use the body mapping strategy you will have to specify the option mappingStrategy as part of the uri, for example:
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hbase:mytable?mappingStrategy=body
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To use the body mapping strategy the body needs to contain an instance of org.apache.camel.component.hbase.model.HBaseData. You can construct t
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HBaseData data = new HBaseData();
HBaseRow row = new HBaseRow();
row.setId("myRowId");
HBaseCell cell = new HBaseCell();
cell.setFamily("myfamily");
cell.setQualifier("myqualifier");
cell.setValue("myValue");
row.getCells().add(cell);
data.addRows().add(row);
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