--- apiVersion: v1 kind: List items: - apiVersion: v1 kind: ConfigMap metadata: labels: funktion.fabric8.io/kind: Connector provider: fabric8 project: connector-velocity version: 1.1.9 group: io.fabric8.funktion.connector name: velocity data: deployment.yml: | --- apiVersion: extensions/v1beta1 kind: Deployment metadata: labels: funktion.fabric8.io/kind: Subscription connector: velocity spec: replicas: 1 template: metadata: labels: funktion.fabric8.io/kind: Subscription connector: velocity spec: containers: - image: fabric8/connector-velocity:1.1.9 name: connector schema.yml: | --- component: kind: component scheme: velocity syntax: velocity:resourceUri title: Velocity description: Transforms the message using a Velocity template. label: transformation deprecated: false async: false producerOnly: true javaType: org.apache.camel.component.velocity.VelocityComponent groupId: org.apache.camel artifactId: camel-velocity version: 2.18.1 componentProperties: velocityEngine: kind: property type: object javaType: org.apache.velocity.app.VelocityEngine deprecated: false secret: false description: To use the VelocityEngine otherwise a new engine is created properties: resourceUri: kind: path group: producer required: true type: string javaType: java.lang.String deprecated: false secret: false description: Path to the resource or a reference to lookup a bean in the Registry to use as the resource contentCache: kind: parameter group: producer type: boolean javaType: boolean deprecated: false secret: false defaultValue: false description: Sets whether to use resource content cache or not encoding: kind: parameter group: producer type: string javaType: java.lang.String deprecated: false secret: false description: Character encoding of the resource content. loaderCache: kind: parameter group: producer type: boolean javaType: boolean deprecated: false secret: false defaultValue: true description: Enables / disables the velocity resource loader cache which is enabled by default propertiesFile: kind: parameter group: producer type: string javaType: java.lang.String deprecated: false secret: false description: The URI of the properties file which is used for VelocityEngine initialization. synchronous: kind: parameter group: advanced label: advanced type: boolean javaType: boolean deprecated: false secret: false defaultValue: false description: Sets whether synchronous processing should be strictly used or Camel is allowed to use asynchronous processing (if supported). documentation.adoc: |+ [[Velocity-Velocity]] Velocity ~~~~~~~~ The *velocity:* component allows you to process a message using an http://velocity.apache.org/[Apache Velocity] template. This can be ideal when using link:templating.html[Templating] to generate responses for requests. Maven users will need to add the following dependency to their `pom.xml` for this component: [source,xml] ------------------------------------------------------------ org.apache.camel camel-velocity x.x.x ------------------------------------------------------------ [[Velocity-URIformat]] URI format ^^^^^^^^^^ [source,java] ------------------------------- velocity:templateName[?options] ------------------------------- Where *templateName* is the classpath-local URI of the template to invoke; or the complete URL of the remote template (eg: file://folder/myfile.vm[file://folder/myfile.vm]). You can append query options to the URI in the following format, `?option=value&option=value&...` [[Velocity-Options]] Options ^^^^^^^ // component options: START The Velocity component supports 1 options which are listed below. {% raw %} [width="100%",cols="2,1m,7",options="header"] |======================================================================= | Name | Java Type | Description | velocityEngine | VelocityEngine | To use the VelocityEngine otherwise a new engine is created |======================================================================= {% endraw %} // component options: END // endpoint options: START The Velocity component supports 6 endpoint options which are listed below: {% raw %} [width="100%",cols="2,1,1m,1m,5",options="header"] |======================================================================= | Name | Group | Default | Java Type | Description | resourceUri | producer | | String | *Required* Path to the resource or a reference to lookup a bean in the Registry to use as the resource | contentCache | producer | false | boolean | Sets whether to use resource content cache or not | encoding | producer | | String | Character encoding of the resource content. | loaderCache | producer | true | boolean | Enables / disables the velocity resource loader cache which is enabled by default | propertiesFile | producer | | String | The URI of the properties file which is used for VelocityEngine initialization. | synchronous | advanced | false | boolean | Sets whether synchronous processing should be strictly used or Camel is allowed to use asynchronous processing (if supported). |======================================================================= {% endraw %} // endpoint options: END [[Velocity-MessageHeaders]] Message Headers ^^^^^^^^^^^^^^^ The velocity component sets a couple headers on the message (you can't set these yourself and from Camel 2.1 velocity component will not set these headers which will cause some side effect on the dynamic template support): [width="100%",cols="10%,90%",options="header",] |======================================================================= |Header |Description |`CamelVelocityResourceUri` |The *templateName* as a `String` object. |`CamelVelocitySupplementalContext` |*Camel 2.16:* To add additional information to the used VelocityContext. The value of this header should be a `Map` with key/values that will added (override any existing key with the same name). + This can be used to pre setup some common key/values you want to reuse in your velocity endpoints. |======================================================================= Headers set during the Velocity evaluation are returned to the message and added as headers. Then its kinda possible to return values from Velocity to the Message. For example, to set the header value of `fruit` in the Velocity template `.tm`: [source,java] ------------------------------- $in.setHeader("fruit", "Apple") ------------------------------- The `fruit` header is now accessible from the `message.out.headers`. [[Velocity-VelocityContext]] Velocity Context ^^^^^^^^^^^^^^^^ Camel will provide exchange information in the Velocity context (just a `Map`). The `Exchange` is transfered as: [width="100%",cols="10%,90%",options="header",] |======================================================================= |key |value |`exchange` |The `Exchange` itself. |`exchange.properties` |The `Exchange` properties. |`headers` |The headers of the In message. |`camelContext` |The Camel Context instance. |`request` |The In message. |`in` |The In message. |`body` |The In message body. |`out` |The Out message (only for InOut message exchange pattern). |`response` |The Out message (only for InOut message exchange pattern). |======================================================================= Since Camel-2.14, you can setup a custom Velocity Context yourself by setting the message header *CamelVelocityContext??*just like this [source,java] ----------------------------------------------------------------------- VelocityContext velocityContext = new VelocityContext(variableMap); exchange.getIn().setHeader("CamelVelocityContext", velocityContext); ----------------------------------------------------------------------- ?? [[Velocity-Hotreloading]] Hot reloading ^^^^^^^^^^^^^ The Velocity template resource is, by default, hot reloadable for both file and classpath resources (expanded jar). If you set `contentCache=true`, Camel will only load the resource once, and thus hot reloading is not possible. This scenario can be used in production, when the resource never changes. [[Velocity-Dynamictemplates]] Dynamic templates ^^^^^^^^^^^^^^^^^ *Available as of Camel 2.1* + Camel provides two headers by which you can define a different resource location for a template or the template content itself. If any of these headers is set then Camel uses this over the endpoint configured resource. This allows you to provide a dynamic template at runtime. [width="100%",cols="10%,10%,80%",options="header",] |======================================================================= |Header |Type |Description |CamelVelocityResourceUri |String |*Camel 2.1:* A URI for the template resource to use instead of the endpoint configured. |CamelVelocityTemplate |String |*Camel 2.1:* The template to use instead of the endpoint configured. |======================================================================= [[Velocity-Samples]] Samples ^^^^^^^ For example you could use something like [source,java] ---------------------------------------- from("activemq:My.Queue"). to("velocity:com/acme/MyResponse.vm"); ---------------------------------------- To use a Velocity template to formulate a response to a message for InOut message exchanges (where there is a `JMSReplyTo` header). If you want to use InOnly and consume the message and send it to another destination, you could use the following route: [source,java] ---------------------------------------- from("activemq:My.Queue"). to("velocity:com/acme/MyResponse.vm"). to("activemq:Another.Queue"); ---------------------------------------- And to use the content cache, e.g. for use in production, where the `.vm` template never changes: [source,java] ---------------------------------------------------------- from("activemq:My.Queue"). to("velocity:com/acme/MyResponse.vm?contentCache=true"). to("activemq:Another.Queue"); ---------------------------------------------------------- And a file based resource: [source,java] ----------------------------------------------------------------- from("activemq:My.Queue"). to("velocity:file://myfolder/MyResponse.vm?contentCache=true"). to("activemq:Another.Queue"); ----------------------------------------------------------------- In *Camel 2.1* it's possible to specify what template the component should use dynamically via a header, so for example: [source,java] --------------------------------------------------------------------------- from("direct:in"). setHeader("CamelVelocityResourceUri").constant("path/to/my/template.vm"). to("velocity:dummy"); --------------------------------------------------------------------------- In *Camel 2.1* it's possible to specify a template directly as a header the component should use dynamically via a header, so for example: [source,java] --------------------------------------------------------------------------------------------------------------- from("direct:in"). setHeader("CamelVelocityTemplate").constant("Hi this is a velocity template that can do templating ${body}"). to("velocity:dummy"); --------------------------------------------------------------------------------------------------------------- [[Velocity-TheEmailSample]] The Email Sample ^^^^^^^^^^^^^^^^ In this sample we want to use Velocity templating for an order confirmation email. The email template is laid out in Velocity as: [source,java] ---------------------------------------------- Dear ${headers.lastName}, ${headers.firstName} Thanks for the order of ${headers.item}. Regards Camel Riders Bookstore ${body} ---------------------------------------------- And the java code: [[Velocity-SeeAlso]] See Also ^^^^^^^^ * link:configuring-camel.html[Configuring Camel] * link:component.html[Component] * link:endpoint.html[Endpoint] * link:getting-started.html[Getting Started]