2. Model :
The first logical layer is the model layer. A Mule model
represents the run-time environment that hosts
services.
It defines the behavior of Mule when processing
requests handled by these services.
Consequently, the model that the Mule instance would
host would establish a runtime environment
optimized for asynchronous processing of messages, as
no synchronous reply is expected anywhere in the
overall message processing chain.
3. Service :
A Mule service is composed of all the Mule entities involved in
processing particular requests in predefined manners.
A service is defined by a specific configuration. This
configuration determines the different elements, from the
different layers of responsibility, that will be mobilized to
process the requests that it'll be open to receive.
Depending on the type of input channel it uses, a service may or
may not be publicly accessible outside of the ESB.
For the time it gets handled by a service, a request is associated
with a session object.
As its name suggests, this object carries all the necessary context
for the pro-cessing of a message while it transits through the
service.
4. Transports :
The transport layer is in charge of receiving or sending
messages. This is why it's involved with both inbound
and outbound communications.
A transport manifests itself in the configuration by the
following elements: connectors, endpoints and
transformers.
5. Connectors :
A connector is in charge of controlling the usage of a
particular protocol.
It's configured with parameters that are specific to this
protocol and holds any state that can be shared with
the underlying entities in charge of the actual
communications.
For example, the FileConnector can read and write file
system files.
6. Configuring connectors :
FileConnector
JDBC Connector
HTTP Connector
STDIO Connector
JMS Connector
Proceed to next slide to see the configuration of all the
above connectors.
7. FileConnector :
The configuration for file connector is as follows:
<file:connector name="FileConnector" streaming="false"
pollingFrequency="1000">
<file:expression-filename-parser/>
</file:connector>
8. JDBC Connector :
The configuration for JDBC connector is as follows :
<jdbc:connector name="jdbcConnector"
dataSource-ref="dataSource“>
<jdbc:query key="statsInsert" value="insert into
alerts values (0, 344, Sindhu', Vankam')"/>
</jdbc:connector>
9. HTTP Connector :
The configuration for HTTP connector is as follows :
<http:connector name="HttpConnector"
proxyHostname="${proxyHostname}"
proxyPort=="${proxyPort}"
proxyUsername="${proxyUsername}"
proxyPassword="${proxyPassword}"/>
10. STDIO Connector :
The configuration for STDIO connector is as follows :
<stdio:connector name="SystemStreamConnector"
promptMessage="Please enter something:"
messageDelayTime="1000" />
11. JMS Connector :
The configuration for JMS connector is as follows :
<jms:activemq-connector
name="jmsQueueConnector"
specification="1.0.2b"
brokerURL="tcp://localhost:61616" />
12. Endpoints :
Inbound and outbound endpoints exist in the context of a
particular service and represent the expected entry and exit
points for messages, respectively.
These end-points are defined in the inbound and outbound
routers.
It's also possible to define an inbound endpoint in a response
router.
In that case, the inbound endpoint acts as a response endpoint
where asynchronous replies will be consolidated before the
service returns its own response.
Global endpoints can be considered abstract entities that get
reified only when referenced in the context of a service: as such,
they're a convenient way to share common configuration
attributes.
13. 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
For examples, the ByteArrayToString transformer converts byte
arrays into String objects.If we want our own transformers to
convert input we can write our own java and we can call from the
mule.
We can implement custom java transformer by extends
AbstractTransformer and AbstractMessageAwareTransformer.
AbstractTransformer is a normal Transformer, it will carry only
payload in the sense input/result from before execution.
AbstractMessageAwareTransformer is a special transformer,
It will carry payload, messahe properties of mule and alo details
regarding exception.
14. Routers :
Routers play a crucial role in controlling the trajectory a message will
follow when it transits in Mule.
They're the gatekeepers of the endpoints of a service. In fact, they act
like railroad switches, taking care of keeping messages on the right
succession of tracks so they can reach their intended destinations.
A router is the object that does something with messages once they
have been received by a connector, or prior to being sent out by the
connector.
pass-through-router: Input will pass as it is to outbound from
inbound. Single service will be available.
filtering-router: input will pass based on condition it's like filtering
input. Multiple Services will be available.
chaining-router: Every statement will pick up by procedure
functionality, nothing but there is no condition after finishing one
service it will go to the next service. Multiple Services will be available.
etc...
15. 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.
Note: writing condition is filtering-router and way of
condition is filter. Based on filter, service will be
picking up by filtering-router.
16. Components :
Components are usually business objects.
They are components that execute business logic on an
incoming event.
Components are standard JavaBeans (containers).
There is no Mule-specific code in components, it is a
java class to implement business logic especially.