Huawei Object Storage Service (OBS)

Since Camel 3.12

Both producer and consumer are supported

Huawei Cloud Object Storage Service (OBS) component allows you to integrate with OBS 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-obs</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI Format

hwcloud-obs:operation[?options]

Configuring Options

Camel components are configured on two separate levels:

  • component level

  • endpoint level

Configuring Component Options

The component level is the highest level which holds general and common configurations that are inherited by the endpoints. 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.

Configuring components can be done with the Component DSL, in a configuration file (application.properties|yaml), or directly with Java code.

Configuring Endpoint Options

Where you find yourself configuring the most is on endpoints, as endpoints often have many options, which allows you to configure what you need the endpoint to do. The options are also categorized into whether the endpoint is used as consumer (from) or as a producer (to), or used for both.

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

A good practice when configuring options is to use Property Placeholders, which allows to not hardcode urls, port numbers, sensitive information, and other settings. In other words placeholders allows to externalize the configuration from your code, and gives more flexibility and reuse.

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

Component Options

The Huawei Object Storage Service (OBS) component supports 3 options, which are listed below.

Name Description Default Type

bridgeErrorHandler (consumer)

Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions, that will be logged at WARN or ERROR level and ignored.

boolean

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.

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.

boolean

Endpoint Options

The Huawei Object Storage Service (OBS) endpoint is configured using URI syntax:

hwcloud-obs: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 (41 parameters)

Name Description Default Type

bucketName (common)

Name of bucket to perform operation on.

String

endpoint (common)

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

String

objectName (common)

Name of object to perform operation with.

String

region (common)

Required OBS service region. This is lower precedence than endpoint based configuration.

String

bridgeErrorHandler (consumer)

Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions, that will be logged at WARN or ERROR level and ignored.

boolean

deleteAfterRead (consumer)

Determines if objects should be deleted after it has been retrieved.

boolean

delimiter (consumer)

The character used for grouping object names.

String

destinationBucket (consumer)

Name of destination bucket where objects will be moved when moveAfterRead is set to true.

String

fileName (consumer)

Get the object from the bucket with the given file name.

String

includeFolders (consumer)

If true, objects in folders will be consumed. Otherwise, they will be ignored and no Exchanges will be created for them.

boolean

maxMessagesPerPoll (consumer)

The maximum number of messages to poll at each polling.

int

moveAfterRead (consumer)

Determines whether objects should be moved to a different bucket after they have been retrieved. The destinationBucket option must also be set for this option to work.

boolean

prefix (consumer)

The object name prefix used for filtering objects to be listed.

String

sendEmptyMessageWhenIdle (consumer)

If the polling consumer did not poll any files, you can enable this option to send an empty message (no body) instead.

boolean

exceptionHandler (consumer (advanced))

To let the consumer use a custom ExceptionHandler. Notice if the option bridgeErrorHandler is enabled then this option is not in use. By default the consumer will deal with exceptions, that will be logged at WARN or ERROR level and ignored.

ExceptionHandler

exchangePattern (consumer (advanced))

Sets the exchange pattern when the consumer creates an exchange.

Enum values:

  • InOnly

  • InOut

  • InOptionalOut

ExchangePattern

pollStrategy (consumer (advanced))

A pluggable org.apache.camel.PollingConsumerPollingStrategy allowing you to provide your custom implementation to control error handling usually occurred during the poll operation before an Exchange have been created and being routed in Camel.

PollingConsumerPollStrategy

bucketLocation (producer)

Location of bucket when creating a new bucket.

String

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.

boolean

proxyHost (proxy)

Proxy server ip/hostname.

String

proxyPassword (proxy)

Proxy authentication password.

String

proxyPort (proxy)

Proxy server port.

int

proxyUser (proxy)

Proxy authentication user.

String

backoffErrorThreshold (scheduler)

The number of subsequent error polls (failed due some error) that should happen before the backoffMultipler should kick-in.

int

backoffIdleThreshold (scheduler)

The number of subsequent idle polls that should happen before the backoffMultipler should kick-in.

int

backoffMultiplier (scheduler)

To let the scheduled polling consumer backoff if there has been a number of subsequent idles/errors in a row. The multiplier is then the number of polls that will be skipped before the next actual attempt is happening again. When this option is in use then backoffIdleThreshold and/or backoffErrorThreshold must also be configured.

int

delay (scheduler)

Milliseconds before the next poll.

long

greedy (scheduler)

If greedy is enabled, then the ScheduledPollConsumer will run immediately again, if the previous run polled 1 or more messages.

boolean

initialDelay (scheduler)

Milliseconds before the first poll starts.

long

repeatCount (scheduler)

Specifies a maximum limit of number of fires. So if you set it to 1, the scheduler will only fire once. If you set it to 5, it will only fire five times. A value of zero or negative means fire forever.

long

runLoggingLevel (scheduler)

The consumer logs a start/complete log line when it polls. This option allows you to configure the logging level for that.

Enum values:

  • TRACE

  • DEBUG

  • INFO

  • WARN

  • ERROR

  • OFF

LoggingLevel

scheduledExecutorService (scheduler)

Allows for configuring a custom/shared thread pool to use for the consumer. By default each consumer has its own single threaded thread pool.

ScheduledExecutorService

scheduler (scheduler)

To use a cron scheduler from either camel-spring or camel-quartz component. Use value spring or quartz for built in scheduler.

Object

schedulerProperties (scheduler)

To configure additional properties when using a custom scheduler or any of the Quartz, Spring based scheduler.

Map

startScheduler (scheduler)

Whether the scheduler should be auto started.

boolean

timeUnit (scheduler)

Time unit for initialDelay and delay options.

Enum values:

  • NANOSECONDS

  • MICROSECONDS

  • MILLISECONDS

  • SECONDS

  • MINUTES

  • HOURS

  • DAYS

TimeUnit

useFixedDelay (scheduler)

Controls if fixed delay or fixed rate is used. See ScheduledExecutorService in JDK for details.

boolean

accessKey (security)

Required Access key for the cloud user.

String

ignoreSslVerification (security)

Ignore SSL verification.

boolean

secretKey (security)

Required Secret key for the cloud user.

String

serviceKeys (security)

Configuration object for cloud service authentication.

ServiceKeys

Usage

Message properties evaluated by the OBS producer

Header Type Description

CamelHwCloudObsOperation

String

Name of operation to invoke

CamelHwCloudObsBucketName

String

Bucket name to invoke operation on

CamelHwCloudObsBucketLocation

String

Bucket location when creating a new bucket

CamelHwCloudObsObjectName

String

Name of the object to be used in operation

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

Message properties set by the OBS producer

Header Type Description

CamelHwCloudObsBucketExists

boolean

Return value when invoking the checkBucketExists operation

Message headers set by the OBS consumer

Header Type Description

CamelHwCloudObsBucketName

String

Name of the bucket where object is contained

CamelHwCloudObsObjectName

String

Name of the object with which the operation is to be performed

CamelHwCloudObsObjectKey

String

The key that the object is stored under

CamelHwCloudObsLastModified

String

The date and time that the object was last modified

Content-Length

String

The size of the object body in bytes

Content-Type

String

The type of content stored in the object

CamelHwCloudObsETag

String

The 128-bit MD5 digest of the Base64 code of the object. This data is the unique identifier of the object content

CamelHwCloudObsContentMD5

String

The 128-bit Base64-encoded digest used to decrypt the object

CamelHwCloudObsObjectType

String

Shows whether the object is a file or a folder

List of Supported OBS Operations

  • listBuckets

  • createBucket - bucketName parameter is required, bucketLocation parameter is optional

  • deleteBucket - bucketName parameter is required

  • checkBucketExists - bucketName parameter is required

  • getBucketMetadata - bucketName parameter is required

  • listObjects - bucketName parameter is required

  • getObject - bucketName and objectName parameters are required

Passing Options Through Exchange Body

There are many options that can be submited to the createBucket and listObjects operations, so they can be passed through the exchange body.

If you would like to configure all the parameters when creating a bucket, you can pass a CreateBucketRequest object or a Json string into the exchange body. If the exchange body is empty, a new bucket will be created using the bucketName and bucketLocation (if provided) passed through the endpoint uri.

from("direct:triggerRoute")
 .setBody(new CreateBucketRequest("Bucket name", "Bucket location"))
 .to("hwcloud-obs:createBucket?region=cn-north-4&accessKey=********&secretKey=********")
from("direct:triggerRoute")
 .setBody("{\"bucketName\":\"Bucket name\",\"location\":\"Bucket location\"}")
 .to("hwcloud-obs:createBucket?region=cn-north-4&accessKey=********&secretKey=********")

If you would like to configure all the parameters when listing objects, you can pass a ListObjectsRequest object or a Json string into the exchange body. If the exchange body is empty, objects will be listed based on the bucketName passed through the endpoint uri.

from("direct:triggerRoute")
 .setBody(new ListObjectsRequest("Bucket name", 1000))
 .to("hwcloud-obs:listObjects?region=cn-north-4&accessKey=********&secretKey=********")
from("direct:triggerRoute")
 .setBody("{\"bucketName\":\"Bucket name\",\"maxKeys\":1000"}")
 .to("hwcloud-obs:listObjects?region=cn-north-4&accessKey=********&secretKey=********")

Using ServiceKey Configuration Bean

Access key and secret keys are required to authenticate against the OBS cloud. 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.obs.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.obs.models.ServiceKeys">
   <property name="accessKey" value="your_access_key" />
   <property name="secretKey" value="your_secret_key" />
</bean>
from("direct:triggerRoute")
 .setProperty(OBSPropeties.OPERATION, constant("createBucket"))
 .setProperty(OBSPropeties.BUCKET_NAME ,constant("your_bucket_name"))
 .setProperty(OBSPropeties.BUCKET_LOCATION, constant("your_bucket_location))
 .to("hwcloud-obs:createBucket?region=cn-north-4&serviceKeys=#myServiceKeyConfig")

Spring Boot Auto-Configuration

When using hwcloud-obs 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-obs-starter</artifactId>
  <version>x.x.x</version>
  <!-- use the same version as your Camel core version -->
</dependency>

The component supports 4 options, which are listed below.

Name Description Default Type

camel.component.hwcloud-obs.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-obs.bridge-error-handler

Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions, that will be logged at WARN or ERROR level and ignored.

false

Boolean

camel.component.hwcloud-obs.enabled

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

Boolean

camel.component.hwcloud-obs.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