Huawei Distributed Message Service (DMS)

Since Camel 3.12

Only producer is supported

Huawei Cloud Distributed Message Service (DMS) component allows you to integrate with DMS provided by Huawei Cloud.

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

<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-huaweicloud-dms</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI Format

hwcloud-dms:operation[?options]

Configuring Options

Camel components are configured on two separate levels:

  • component level

  • endpoint level

Configuring Component Options

At the component level, you set general and shared configurations that are, then, inherited by the endpoints. It is the highest configuration level.

For example, a component may have security settings, credentials for authentication, urls for network connection and so forth.

Some components only have a few options, and others may have many. Because components typically have pre-configured defaults that are commonly used, then you may often only need to configure a few options on a component; or none at all.

You can configure components using:

  • the Component DSL.

  • in a configuration file (application.properties, *.yaml files, etc).

  • directly in the Java code.

Configuring Endpoint Options

You usually spend more time setting up endpoints because they have many options. These options help you customize what you want the endpoint to do. The options are also categorized into whether the endpoint is used as a consumer (from), as a producer (to), or both.

Configuring endpoints is most often done directly in the endpoint URI as path and query parameters. You can also use the Endpoint DSL and DataFormat DSL as a type safe way of configuring endpoints and data formats in Java.

A good practice when configuring options is to use Property Placeholders.

Property placeholders provide a few benefits:

  • They help prevent using hardcoded urls, port numbers, sensitive information, and other settings.

  • They allow externalizing the configuration from the code.

  • They help the code to become more flexible and reusable.

The following two sections list all the options, firstly for the component followed by the endpoint.

Component Options

The Huawei Distributed Message Service (DMS) component supports 2 options, which are listed below.

Name Description Default Type

lazyStartProducer (producer)

Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing.

false

boolean

autowiredEnabled (advanced)

Whether autowiring is enabled. This is used for automatic autowiring options (the option must be marked as autowired) by looking up in the registry to find if there is a single instance of matching type, which then gets configured on the component. This can be used for automatic configuring JDBC data sources, JMS connection factories, AWS Clients, etc.

true

boolean

Endpoint Options

The Huawei Distributed Message Service (DMS) endpoint is configured using URI syntax:

hwcloud-dms:operation

With the following path and query parameters:

Path Parameters (1 parameters)

Name Description Default Type

operation (producer)

Required Operation to be performed.

String

Query Parameters (29 parameters)

Name Description Default Type

accessKey (producer)

Required Access key for the cloud user.

String

accessUser (producer)

The username of a RabbitMQ instance. This option is mandatory when creating a RabbitMQ instance.

String

availableZones (producer)

The ID of an available zone. This option is mandatory when creating an instance and it cannot be an empty array.

List

endpoint (producer)

DMS url. Carries higher precedence than region parameter based client initialization.

String

engine (producer)

The message engine. Either kafka or rabbitmq. If the parameter is not specified, all instances will be queried.

Enum values:

  • kafka

  • rabbitmq

String

engineVersion (producer)

The version of the message engine. This option is mandatory when creating an instance.

String

ignoreSslVerification (producer)

Ignore SSL verification.

false

boolean

instanceId (producer)

The id of the instance. This option is mandatory when deleting or querying an instance.

String

kafkaManagerPassword (producer)

The password for logging in to the Kafka Manager. This option is mandatory when creating a Kafka instance.

String

kafkaManagerUser (producer)

The username for logging in to the Kafka Manager. This option is mandatory when creating a Kafka instance.

String

name (producer)

The name of the instance for creating and updating an instance. This option is mandatory when creating an instance.

String

partitionNum (producer)

The maximum number of partitions in a Kafka instance. This option is mandatory when creating a Kafka instance.

int

password (producer)

The password of a RabbitMQ instance. This option is mandatory when creating a RabbitMQ instance.

String

productId (producer)

The product ID. This option is mandatory when creating an instance.

String

projectId (producer)

Required Cloud project ID.

String

proxyHost (producer)

Proxy server ip/hostname.

String

proxyPassword (producer)

Proxy authentication password.

String

proxyPort (producer)

Proxy server port.

int

proxyUser (producer)

Proxy authentication user.

String

region (producer)

Required DMS service region.

String

secretKey (producer)

Required Secret key for the cloud user.

String

securityGroupId (producer)

The security group which the instance belongs to. This option is mandatory when creating an instance.

String

serviceKeys (producer)

Configuration object for cloud service authentication.

ServiceKeys

specification (producer)

The baseline bandwidth of a Kafka instance. This option is mandatory when creating a Kafka instance.

String

storageSpace (producer)

The message storage space. This option is mandatory when creating an instance.

int

storageSpecCode (producer)

The storage I/O specification. This option is mandatory when creating an instance.

String

subnetId (producer)

The subnet ID. This option is mandatory when creating an instance.

String

vpcId (producer)

The VPC ID. This option is mandatory when creating an instance.

String

lazyStartProducer (producer (advanced))

Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing.

false

boolean

Usage

Message properties evaluated by the DMS producer

Header Type Description

CamelHwCloudDmsOperation

String

Name of operation to invoke

CamelHwCloudDmsEngine

String

The message engine. Either kafka or rabbitmq

CamelHwCloudDmsInstanceId

String

Instance ID to invoke operation on

CamelHwCloudDmsName

String

The name of the instance for creating and updating an instance

CamelHwCloudDmsEngineVersion

String

The version of the message engine

CamelHwCloudDmsSpecification

String

The baseline bandwidth of a Kafka instance

CamelHwCloudDmsStorageSpace

int

The message storage space

CamelHwCloudDmsPartitionNum

int

The maximum number of partitions in a Kafka instance

CamelHwCloudDmsAccessUser

String

The username of a RabbitMQ instance

CamelHwCloudDmsPassword

String

The password of a RabbitMQ instance

CamelHwCloudDmsVpcId

String

The VPC ID

CamelHwCloudDmsSecurityGroupId

String

The security group which the instance belongs to

CamelHwCloudDmsSubnetId

String

The subnet ID

CamelHwCloudDmsAvailableZones

List<String>

The ID of an available zone

CamelHwCloudDmsProductId

String

The product ID

CamelHwCloudDmsKafkaManagerUser

String

The username for logging in to the Kafka Manager

CamelHwCloudDmsKafkaManagerPassword

String

The password for logging in to the Kafka Manager

CamelHwCloudDmsStorageSpecCode

String

The storage I/O specification

If any of the above properties are set, they will override their corresponding query parameter.

Message properties set by the DMS producer

Header Type Description

CamelHwCloudDmsInstanceDeleted

boolean

Set as true when the deleteInstance operation is successful

CamelHwCloudDmsInstanceUpdated

boolean

Set as true when the updateInstance operation is successful

List of Supported DMS Operations

  • createInstance

  • deleteInstance

  • listInstances

  • queryInstance

  • updateInstance

Create Instance

To create an instance, you can pass the parameters through the endpoint, the exchange properties, and the exchange body as a CreateInstanceRequestBody object or a valid JSON String representation of it. Refer to this for the Kafka parameters and the RabbitMQ parameters. If you choose to pass these parameters through the endpoint or through exchange properties, you can only input the mandatory parameters shown in those links. If you would like to have access to all the parameters, you must pass a CreateInstanceRequestBody object or a valid JSON String representation of it through the exchange body, as shown below:

from("direct:triggerRoute")
 .setBody(new CreateInstanceRequestBody().withName("new-instance").withDescription("description").with*) // add remaining options
 .to("hwcloud-dms:createInstance?region=cn-north-4&accessKey=********&secretKey=********&projectId=*******")
from("direct:triggerRoute")
 .setBody("{\"name\":\"new-instance\",\"description\":\"description\"}") // add remaining options
 .to("hwcloud-dms:createInstance?region=cn-north-4&accessKey=********&secretKey=********&projectId=*******")

Update Instance

To update an instance, you must pass the parameters through the exchange body as an UpdateInstanceRequestBody or a valid JSON String representation of it. Refer to this for the Kafka parameters and the RabbitMQ parameters. An example of how to do this is shown below:

from("direct:triggerRoute")
 .setBody(new UpdateInstanceRequestBody().withName("new-instance").withDescription("description").with*) // add remaining options
 .to("hwcloud-dms:updateInstance?instanceId=******&region=cn-north-4&accessKey=********&secretKey=********&projectId=*******")
from("direct:triggerRoute")
 .setBody("{\"name\":\"new-instance\",\"description\":\"description\"}") // add remaining options
 .to("hwcloud-dms:updateInstance?instanceId=******&region=cn-north-4&accessKey=********&secretKey=********&projectId=*******")

Using ServiceKey Configuration Bean

Access key and secret keys are required to authenticate against cloud DMS service. You can avoid having them being exposed and scattered over in your endpoint uri by wrapping them inside a bean of class org.apache.camel.component.huaweicloud.common.models.ServiceKeys. Add it to the registry and let Camel look it up by referring the object via endpoint query parameter serviceKeys.

Check the following code snippets:

<bean id="myServiceKeyConfig" class="org.apache.camel.component.huaweicloud.common.models.ServiceKeys">
   <property name="accessKey" value="your_access_key" />
   <property name="secretKey" value="your_secret_key" />
</bean>
from("direct:triggerRoute")
 .to("hwcloud-dms:listInstances?region=cn-north-4&serviceKeys=#myServiceKeyConfig")

Spring Boot Auto-Configuration

When using hwcloud-dms with Spring Boot make sure to use the following Maven dependency to have support for auto configuration:

<dependency>
  <groupId>org.apache.camel.springboot</groupId>
  <artifactId>camel-huaweicloud-dms-starter</artifactId>
  <version>x.x.x</version>
  <!-- use the same version as your Camel core version -->
</dependency>

The component supports 3 options, which are listed below.

Name Description Default Type

camel.component.hwcloud-dms.autowired-enabled

Whether autowiring is enabled. This is used for automatic autowiring options (the option must be marked as autowired) by looking up in the registry to find if there is a single instance of matching type, which then gets configured on the component. This can be used for automatic configuring JDBC data sources, JMS connection factories, AWS Clients, etc.

true

Boolean

camel.component.hwcloud-dms.enabled

Whether to enable auto configuration of the hwcloud-dms component. This is enabled by default.

Boolean

camel.component.hwcloud-dms.lazy-start-producer

Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing.

false

Boolean