Chapter 112. Solr
Solr Component
Available as of Camel 2.9
The Solr component allows you to interface with an Apache Lucene Solr server (based on SolrJ 3.5.0).
Maven users will need to add the following dependency to their
pom.xml for this component:
<dependency>
<groupId>org.apache.camel</groupId>
<artifactId>camel-solr</artifactId>
<version>x.x.x</version>
<!-- use the same version as your Camel core version -->
</dependency>URI format
solr://host[:port]/solr?[options]
Endpoint Options
The following SolrServer options may be configured on the Solr endpoint.
| name | default value | description |
|---|---|---|
maxRetries
|
0
|
maximum number of retries to attempt in the event of transient errors |
soTimeout
|
1000
|
read timeout on the underlying HttpConnectionManager. This is desirable for queries, but probably not for indexing |
connectionTimeout
|
100
|
connectionTimeout on the underlying HttpConnectionManager |
defaultMaxConnectionsPerHost
|
2
|
maxConnectionsPerHost on the underlying HttpConnectionManager |
maxTotalConnections
|
20
|
maxTotalConnection on the underlying HttpConnectionManager |
followRedirects
|
false
|
indicates whether redirects are used to get to the Solr server |
allowCompression
|
false
|
server side must support gzip or deflate for this to have any effect |
requestHandler
|
/update (xml) | set the request handler to be used |
streamingThreadCount
|
2
|
Camel 2.9.2 set the number of threads for the StreamingUpdateSolrServer |
streamingQueueSize
|
10
|
Camel 2.9.2 set the queue size for the StreamingUpdateSolrServer |
Message Operations
The following Solr operations are currently supported. Simply set an exchange header with a key of "SolrOperation" and a value set to one of the following. Some operations also require the message body to be set.
- the
INSERToperations use the CommonsHttpSolrServer
| operation | message body | description |
|---|---|---|
INSERT/INSERT_STREAMING
|
n/a | adds an index using message headers (must be prefixed with "SolrField.") |
INSERT/INSERT_STREAMING
|
File | adds an index using the given File (using ContentStreamUpdateRequest) |
INSERT/INSERT_STREAMING
|
SolrInputDocument | Camel 2.9.2 updates index based on the given SolrInputDocument |
INSERT/INSERT_STREAMING
|
String XML | Camel 2.9.2 updates index based on the given XML (must follow SolrInputDocument format) |
ADD_BEAN
|
bean instance | adds an index based on values in an annotated bean |
DELETE_BY_ID
|
index id to delete | delete a record by ID |
DELETE_BY_QUERY
|
query string | delete a record by a query |
COMMIT
|
n/a | performs a commit on any pending index changes |
ROLLBACK
|
n/a | performs a rollback on any pending index changes |
OPTIMIZE
|
n/a | performs a commit on any pending index changes and then runs the optimize command |
Example
Below is a simple
INSERT, DELETE and COMMIT example
from("direct:insert")
.setHeader(SolrConstants.OPERATION, constant(SolrConstants.OPERATION_INSERT))
.setHeader(SolrConstants.FIELD + "id", body())
.to("solr://localhost:8983/solr");
from("direct:delete")
.setHeader(SolrConstants.OPERATION, constant(SolrConstants.OPERATION_DELETE_BY_ID))
.to("solr://localhost:8983/solr");
from("direct:commit")
.setHeader(SolrConstants.OPERATION, constant(SolrConstants.OPERATION_COMMIT))
.to("solr://localhost:8983/solr");<route>
<from uri="direct:insert"/>
<setHeader headerName="SolrOperation">
<constant>INSERT</constant>
</setHeader>
<setHeader headerName="SolrField.id">
<simple>${body}</simple>
</setHeader>
<to uri="solr://localhost:8983/solr"/>
</route>
<route>
<from uri="direct:delete"/>
<setHeader headerName="SolrOperation">
<constant>DELETE_BY_ID</constant>
</setHeader>
<to uri="solr://localhost:8983/solr"/>
</route>
<route>
<from uri="direct:commit"/>
<setHeader headerName="SolrOperation">
<constant>COMMIT</constant>
</setHeader>
<to uri="solr://localhost:8983/solr"/>
</route>
A client would simply need to pass a message body to the insert route or to the delete route, and then call the commit route.
template.sendBody("direct:insert", "1234");
template.sendBody("direct:commit", null);
template.sendBody("direct:delete", "1234");
template.sendBody("direct:commit", null);Querying Solr
Currently, this component doesn't support querying data natively (may be added later). For now, you can query Solr using HTTP as follows:
//define the route to perform a basic query
from("direct:query")
.recipientList(simple("http://localhost:8983/solr/select/?q=${body}"))
.convertBodyTo(String.class);
...
//query for an id of '1234' (url encoded)
String responseXml = (String) template.requestBody("direct:query", "id%3A1234");
For more information, see these resources...
