![M
D Copyright 2006-2009 Dan McCreary & Associates 33
Keeping the Name The Same
<outbound-router>
<router
className="org.mule.routing.outbound.OutboundPassThroughRouter">
<endpoint
address=
"file:///c:/mule-class/out?outputPattern=$[ORIGINALNAME]"
/>
</router>
</outbound-router>
Add the outputPattern parameter to keep the output
name the same as the input.](https://image.slidesharecdn.com/mule-overview-220915101257-de89ec92/85/mule-overview-ppt-33-320.jpg)
![M
D Copyright 2006-2009 Dan McCreary & Associates 38
Validating against an XML Schema
<outbound-router>
<router className="org.mule.routing.outbound.FilteringXmlMessageSplitter">
<endpoint
address="file:///c:/mule-class/out?outputPattern=$[ORIGINALNAME]"/>
<properties>
<property name="validateSchema" value="true"/>
<property name="externalSchemaLocation"
value="file:///c:/mule-class/labs/07-validate/my-
schema.xsd"/>
</properties>
</router>
</outbound-router>
To validate the XML Schema, just add two properties:
1) tell it to validate the document
2) tell it what file to use and where to find it](https://image.slidesharecdn.com/mule-overview-220915101257-de89ec92/85/mule-overview-ppt-38-320.jpg)
mule-overview.ppt
- 1. M D Copyright 2006-2009 Dan McCreary & Associates 1 The Enterprise Service Bus Introduction using Mule Introduction to Open-Source ESB Authors: Dan McCreary and Arun Batchu Date: 11/20/2006 Version: DRAFT 0.2
- 2. M D Copyright 2006-2009 Dan McCreary & Associates 2 Agenda • What is Mule? • How do you use Mule? • What are the core Mule concepts? • Learning mule with File endpoints
- 3. M D Copyright 2006-2009 Dan McCreary & Associates 3 Enterprise Service Backbone • Mule is an open-source Enterprise Service Backbone (ESB)
- 4. M D Copyright 2006-2009 Dan McCreary & Associates 4 Mule is Has Advanced Technologies • SEDA – Staged Event-Driven Architecture • Java NIO – Java New Input/Output
- 5. M D Copyright 2006-2009 Dan McCreary & Associates 5 SEDA • SEDA decomposes a complex, event-driven software application into a set of stages connected by queues • This design avoids the high overhead associated with thread-based concurrency models, and decouples event and thread scheduling from application logic • By performing admission control on each event queue, the service can be well-conditioned to load, preventing resources from being overcommitted when demand exceeds service capacity • SEDA employs dynamic control to automatically tune runtime parameters (such as the scheduling parameters of each stage) as well as to manage load, for example, by performing adaptive load shedding • Decomposing services into a set of stages also enables modularity and code reuse, as well as the development of debugging tools for complex event- driven applications
- 6. M D Copyright 2006-2009 Dan McCreary & Associates 6 Java NIO • NIO is a collection of Java programming language APIs that offer advanced features for intensive I/O operations • NIO facilitates an implementations that can directly use the most efficient operations of the underlying platform • NIO includes: – Buffers for data of primitive types – Character set encoders and decoders – A pattern-matching facility based on Perl-style regular expressions (in package java.util.regex) – Channels, a new primitive I/O abstraction – A file interface that supports locks and memory mapping – A multiplexed, non-blocking I/O facility for writing scalable servers
- 7. M D Copyright 2006-2009 Dan McCreary & Associates 7 Mule’s “Moves Things Around” • Folder to folder • Queue to queue • Shared memory to shared memory • Using different types of transports • In a flexible way
- 8. M D Copyright 2006-2009 Dan McCreary & Associates 8 XML Pipeline • An XML pipeline is a series of operation that are performed on one or more XML files • Examples include: – validate – transform – prune (remove nodes) – split (break a single XML file into many files) – merge (join two or more files together)
- 9. M D Copyright 2006-2009 Dan McCreary & Associates 9 CRV Example • Flow of XML document through approval processes Submit CRV Deed Matched CRV SSN Stripped CRV Income Tax Audit County Audit County Approval State Audit State Approval
- 10. M D Copyright 2006-2009 Dan McCreary & Associates 10 Decomposition • Example of XML Operations used on CRV Validate Split Remove SSN Element Store Modify Value Add Element Modify Value Add Element
- 11. M D Copyright 2006-2009 Dan McCreary & Associates 11 Declarative Approach • Focus on specifying "What" not "How" • Empower business analysis to write machine-readable specifications • Hide the "How" behind services with clear interfaces (SOA)
- 12. M D Copyright 2006-2009 Dan McCreary & Associates 12 Core Mule Concepts • Mule Manager • Mule Model • Universal Message Object (UMO) • Endpoints • External Applications
- 13. M D Copyright 2006-2009 Dan McCreary & Associates 13 Universal Message Object (UMO) • A UMO is a type of Java object that can – receive events "from anywhere" – send events • UMO Components are usually your business objects. They are components that execute business logic on an incoming event • UMO are standard JavaBeans (containers) • There is no Mule-specific code in your components • Mule handles all routing and transformation of events to and from your objects based on the configuration of your component
- 14. M D Copyright 2006-2009 Dan McCreary & Associates 14 Transport • A transport or "provider", is a set of objects that add support to Mule to handle a specific kind of transport or protocol • Examples – the "Email Provider" enables Mule to send and receive messages via the SMTP, POP and IMAP protocols
- 15. M D Copyright 2006-2009 Dan McCreary & Associates 15 Connector • A connector is the object that sends and receives messages on behalf of an endpoint. • Connectors are bundled as part of specific transports or providers. • For example, the FileConnector can read and write file system files.
- 16. M D Copyright 2006-2009 Dan McCreary & Associates 16 Router • A router is the object that do something with messages once they have been received by a connector, or prior to being sent out by the connector
- 17. M D Copyright 2006-2009 Dan McCreary & Associates 17 Filter • A filter optionally filters incoming or outgoing messages that are coming into or going out from a connector. • For example, the File Provider comes with a FilenameWildcardFilter that restricts which files are read by the connector based on file name patterns. For example only files with the .xml extension can be routed. • Filters are used in conjunction with Routers.
- 18. M D Copyright 2006-2009 Dan McCreary & Associates 18 Transformer • A transformer optionally changes incoming or outgoing messages in some way • This is usually done to make the message format useable by a downstream function • Examples: – the ByteArrayToString transformer converts byte arrays into String objects.
- 19. M D Copyright 2006-2009 Dan McCreary & Associates 19 Mule Event Flow • The nine stages of a mule event – first 2 – inbound – middle 4 – component – last 2 – outbound Endpoint (Message Receiver) Endpoint (Message Dispatcher) Inbound Router Outbound Router Inbound Transformer Outbound Transformer Interceptor Service Invocation Interceptor Inbound Component Outbound Optional Step
- 20. M D Copyright 2006-2009 Dan McCreary & Associates 20 Message Receiver Endpoint • Some event triggers a message flow – A file being written into a folder – A message arriving on a message queue – A record in a database – Data written to a socket Endpoint (Message Dispatcher) Inbound Router Outbound Router Inbound Transformer Outbound Transformer Interceptor Service Invocation Interceptor Endpoint (Message Receiver)
- 21. M D Copyright 2006-2009 Dan McCreary & Associates 21 Inbound Router • The inbound router is the fist step in a message. Functions typically performed by an inbound router – Filtering – Remove duplicate messages – Matching messages – Aggregation (combining) – Re-sequence data – Forwarding • See also – IdempotentReceiver – CorrolationAggregator – CorrelationResequencer Endpoint (Message Dispatcher) Inbound Router Outbound Router Inbound Transformer Outbound Transformer Interceptor Service Invocation Interceptor Endpoint (Message Receiver)
- 22. M D Copyright 2006-2009 Dan McCreary & Associates 22 Interceptor • Used to intercept message flow into your service component • Used trigger monitor/events or interrupt the flow of the message • Example: an authorization interceptor could ensure that the current request has the correct credentials to invoke the service. Endpoint (Message Dispatcher) Inbound Router Outbound Router Inbound Transformer Outbound Transformer Service Invocation Interceptor Endpoint (Message Receiver) Interceptor
- 23. M D Copyright 2006-2009 Dan McCreary & Associates 23 Inbound Transformer • If the inbound data is not in the correct format for the service it must be transformed at this point Endpoint (Message Receiver) Endpoint (Message Dispatcher) Inbound Router Outbound Router Outbound Transformer Interceptor Service Invocation Interceptor Inbound Transformer
- 24. M D Copyright 2006-2009 Dan McCreary & Associates 24 Service Invocation • The actual service is performed • In mule, this is generally a Java object • Service invocation can also be a "pass through" Endpoint (Message Receiver) Endpoint (Message Dispatcher) Inbound Router Outbound Router Outbound Transformer Interceptor Interceptor Inbound Transformer Service Invocation
- 25. M D Copyright 2006-2009 Dan McCreary & Associates 25 Outbound Router • Dispatching the data to all the relevant endpoints Endpoint (Message Receiver) Endpoint (Message Dispatcher) Inbound Router Outbound Transformer Interceptor Interceptor Inbound Transformer Service Invocation Outbound Router
- 26. M D Copyright 2006-2009 Dan McCreary & Associates 26 Built-in Router Classes Inbound Outbound Response Idempotent Receiver Filtering Outbound Router Response Aggregator Selective Consumer Recipient List Aggregator Multicasting Router Resequencer Chaining Router Forwarding Consumer Message Splitter Filtering List Message Splitter Filtering Xml Message Splitter Exception Based Router
- 27. M D Copyright 2006-2009 Dan McCreary & Associates 27 Outbound Transformer • Any transformations that needs to be done on the message after a service has been performed on the message can be executed before it is put into the endpoint • See Also – EnvelopeInterceptor Endpoint (Message Receiver) Endpoint (Message Dispatcher) Inbound Router Interceptor Interceptor Inbound Transformer Service Invocation Outbound Router Outbound Transformer
- 28. M D Copyright 2006-2009 Dan McCreary & Associates 28 Test Environment
- 29. M D Copyright 2006-2009 Dan McCreary & Associates 29 Omitted From Examples for Brevity <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE mule-configuration PUBLIC "-//MuleSource //DTD mule-configuration XML V1.0//EN" "http://mule.mulesource.org/dtds/mule- configuration.dtd">
- 30. M D Copyright 2006-2009 Dan McCreary & Associates 30 Outline of Move All Files <mule-configuration> <model> <mule-descriptor> <inbound-router> <endpoint address="file:///c:/mule-class/in"/> </inbound-router> <outbound-router> <router> <endpoint address="file:///c:/mule-class/out"/> </router> </outbound-router> </mule-descriptor> </model> </mule-configuration>
- 31. M D Copyright 2006-2009 Dan McCreary & Associates 31 Move All Files – Procedural Details <mule-configuration id="Mule_File_Move" version=" 1.0"> <connector name="SystemStreamConnector" className="org.mule.providers.stream.SystemStreamConnector" /> <model name="move-all-files"> <mule-descriptor name="move-file" implementation="org.mule.components.simple.BridgeComponent" > <inbound-router> <endpoint address="file:///c:/tmp/in"/> </inbound-router> <outbound-router> <router className="org.mule.routing.outbound.OutboundPassThroughRou ter"> <endpoint address="file:///c:/tmp/out"/> </router> </outbound-router> </mule-descriptor> </model> </mule-configuration>
- 32. M D Copyright 2006-2009 Dan McCreary & Associates 32 Only Moving XML Files <inbound-router> <endpoint address="file:///c:/mule-class/in"> <filter pattern="*.xml" className= "org.mule.providers.file.filters.FilenameWildcardFilter"/> </endpoint> </inbound-router> Add the filter line to only move files with the extension "*.xml". If you add a file "foobar.txt to the input folder it will not be moved.
- 33. M D Copyright 2006-2009 Dan McCreary & Associates 33 Keeping the Name The Same <outbound-router> <router className="org.mule.routing.outbound.OutboundPassThroughRouter"> <endpoint address= "file:///c:/mule-class/out?outputPattern=$[ORIGINALNAME]" /> </router> </outbound-router> Add the outputPattern parameter to keep the output name the same as the input.
- 34. M D Copyright 2006-2009 Dan McCreary & Associates 34 Happy Path and Exceptions • By default, error free documents follow a central path known as the "happy path" • Documents that have errors may be handled in different ways (rejected, warnings etc.) Start Stop Step 1 Step 2 Step 3 Stop Stop Stop
- 35. M D Copyright 2006-2009 Dan McCreary & Associates 35 Exception Handling • Mule has a special way of handling non-happy path processing. This is called an "Exception Strategy" but is it really just and exception path and there is very little strategy involved. • There are three places you can associate an exception strategy – connector – component – model (set for all components in a model)
- 36. M D Copyright 2006-2009 Dan McCreary & Associates 36 Exception Strategy <exception-strategy className=org.mule.impl.DefaultComponentExceptionStrategy"> <endpoint address="file:///c:/mule-class/error"/> </exception-strategy> We want all invalid documents to be moved into the error folder.
- 37. M D Copyright 2006-2009 Dan McCreary & Associates 37 Sample XML <?xml version="1.0" encoding="UTF-8"?> <Data> <Element1>Hello World!</Element1> <Element2>String</Element2> <Element3>String</Element3> <DansInvalidDataElement>This is Dans invalid data element</DansInvalidDataElement> </Data> XML Schema validation will generate an error message when it gets to the fourth invalid data element: Given the following XML Schema file:
- 38. M D Copyright 2006-2009 Dan McCreary & Associates 38 Validating against an XML Schema <outbound-router> <router className="org.mule.routing.outbound.FilteringXmlMessageSplitter"> <endpoint address="file:///c:/mule-class/out?outputPattern=$[ORIGINALNAME]"/> <properties> <property name="validateSchema" value="true"/> <property name="externalSchemaLocation" value="file:///c:/mule-class/labs/07-validate/my- schema.xsd"/> </properties> </router> </outbound-router> To validate the XML Schema, just add two properties: 1) tell it to validate the document 2) tell it what file to use and where to find it
- 39. M D Copyright 2006-2009 Dan McCreary & Associates 39 Error Message document : cvc-complex-type.2.4.d: Invalid content was found starting with element 'DansInvalidDataElement'. No child element is expected at this point. This error message is generated on the Mule console when an invalid data element is found. But what should we do with it? How do we redirect it to the appropriate user?
- 40. M D Copyright 2006-2009 Dan McCreary & Associates 40 Thank You! Please contact me for more information: • Enterprise Service Bus • Enterprise Integration • Metadata Management • Metadata Registries • Service Oriented Architectures • Business Intelligence and Data Warehouse • Semantic Web Dan McCreary, President Dan McCreary & Associates Metadata Strategy Development [email protected] (952) 931-9198