Repository: camel Updated Branches: refs/heads/master af50946b7 -> 1aa62f89e
Added Avro Dataformat to Gitbook Project: http://git-wip-us.apache.org/repos/asf/camel/repo Commit: http://git-wip-us.apache.org/repos/asf/camel/commit/1aa62f89 Tree: http://git-wip-us.apache.org/repos/asf/camel/tree/1aa62f89 Diff: http://git-wip-us.apache.org/repos/asf/camel/diff/1aa62f89 Branch: refs/heads/master Commit: 1aa62f89e968c3c504ae69b8ba7d25a658c16b03 Parents: af50946 Author: Andrea Cosentino <[email protected]> Authored: Tue Aug 23 13:46:17 2016 +0200 Committer: Andrea Cosentino <[email protected]> Committed: Tue Aug 23 13:46:17 2016 +0200 ---------------------------------------------------------------------- .../src/main/docs/avro-dataformat.adoc | 152 +++++++++++++++++++ 1 file changed, 152 insertions(+) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/camel/blob/1aa62f89/components/camel-avro/src/main/docs/avro-dataformat.adoc ---------------------------------------------------------------------- diff --git a/components/camel-avro/src/main/docs/avro-dataformat.adoc b/components/camel-avro/src/main/docs/avro-dataformat.adoc new file mode 100644 index 0000000..f474baf --- /dev/null +++ b/components/camel-avro/src/main/docs/avro-dataformat.adoc @@ -0,0 +1,152 @@ +[[avro-AvroDataformat]] +Avro Dataformat +~~~~~~~~~~~~~~~ + +*Available as of Camel 2.10* + +This component provides a dataformat for avro, which allows +serialization and deserialization of messages using Apache Avro's binary +dataformat. Moreover, it provides support for Apache Avro's rpc, by +providing producers and consumers endpoint for using avro over netty or +http. + +Maven users will need to add the following dependency to their `pom.xml` +for this component: + +[source,xml] +------------------------------------------------------------ +<dependency> + <groupId>org.apache.camel</groupId> + <artifactId>camel-avro</artifactId> + <version>x.x.x</version> + <!-- use the same version as your Camel core version --> +</dependency> +------------------------------------------------------------ + +[[avro-ApacheAvroOverview]] +Apache Avro Overview +^^^^^^^^^^^^^^^^^^^^ + +Avro allows you to define message types and a protocol using a json like +format and then generate java code for the specified types and messages. +An example of how a schema looks like is below. + +[source,xml] +------------------------------------------------------------------------------------------ +{"namespace": "org.apache.camel.avro.generated", + "protocol": "KeyValueProtocol", + + "types": [ + {"name": "Key", "type": "record", + "fields": [ + {"name": "key", "type": "string"} + ] + }, + {"name": "Value", "type": "record", + "fields": [ + {"name": "value", "type": "string"} + ] + } + ], + + "messages": { + "put": { + "request": [{"name": "key", "type": "Key"}, {"name": "value", "type": "Value"} ], + "response": "null" + }, + "get": { + "request": [{"name": "key", "type": "Key"}], + "response": "Value" + } + } +} +------------------------------------------------------------------------------------------ + +You can easily generate classes from a schema, using maven, ant etc. +More details can be found at the +http://avro.apache.org/docs/current/[Apache Avro documentation]. + +However, it doesn't enforce a schema first approach and you can create +schema for your existing classes. *Since 2.12* you can use existing +protocol interfaces to make RCP calls. You should use interface for the +protocol itself and POJO beans or primitive/String classes for parameter +and result types. Here is an example of the class that corresponds to +schema above: + +[source,java] +-------------------------------------------------------------- +package org.apache.camel.avro.reflection; + +public interface KeyValueProtocol { + void put(String key, Value value); + Value get(String key); +} + +class Value { + private String value; + public String getValue() { return value; } + public void setValue(String value) { this.value = value; } +} +-------------------------------------------------------------- + +_Note: Existing classes can be used only for RPC (see below), not in +data format._ + +[[avro-UsingtheAvrodataformat]] +Using the Avro data format +^^^^^^^^^^^^^^^^^^^^^^^^^^ + +Using the avro data format is as easy as specifying that the class that +you want to marshal or unmarshal in your route. + +[source,xml] +-------------------------------------------------------------------------------- + <camelContext id="camel" xmlns="http://camel.apache.org/schema/spring";> + <route> + <from uri="direct:in"/> + <marshal> + <avro instanceClass="org.apache.camel.dataformat.avro.Message"/> + </marshal> + <to uri="log:out"/> + </route> + </camelContext> +-------------------------------------------------------------------------------- + +An alternative can be to specify the dataformat inside the context and +reference it from your route. + +[source,xml] +-------------------------------------------------------------------------------------- + <camelContext id="camel" xmlns="http://camel.apache.org/schema/spring";> + <dataFormats> + <avro id="avro" instanceClass="org.apache.camel.dataformat.avro.Message"/> + </dataFormats> + <route> + <from uri="direct:in"/> + <marshal ref="avro"/> + <to uri="log:out"/> + </route> + </camelContext> +-------------------------------------------------------------------------------------- + +In the same manner you can umarshal using the avro data format. + + +[[avro-AvroDataformat-options]] +Avro Dataformat Options +^^^^^^^^^^^^^^^^^^^^^^^ + +// dataformat options: START +The Avro dataformat supports 1 options which are listed below. + + + +{% raw %} +[width="100%",cols="2s,1m,1m,6",options="header"] +|======================================================================= +| Name | Default | Java Type | Description +| instanceClassName | | String | Class name to use for marshal and unmarshalling +|======================================================================= +{% endraw %} +// dataformat options: END +
