MuleSoft latest launch Mule 4 offers some interesting integration solutions for businesses at a low cost and simplified way, compared to its prior version Mule 3 release. Migrating from Mule 3 to Mule 4 should be carried out with utmost care. So to assist businesses in secured migration process here we discuss in detail on how to conduct migration process from Mule 3 to Mule 4

1. Migratingto Mule 4
Are you ready for this?
- Harish Kumar

2. Who am I?
• Working as Principal Architect for my
current company
• MuleSoft Meetup organizer for Japan
• Love writing blogs and create tutorial
videos
• https://www.youtube.com/c/RightC
ode
• https://dzone.com/users/2876594/
rdatdzone.html
• Featured Trailblazer
• https://trailhead.salesforce.com/en
/trailblazers/harish-kumar
• Reach me @
• https://jp.linkedin.com/in/echarish
• https://twitter.com/harish884
• https://twitter.com/RightCodeHere
?lang=en

3. Measures to Understand Prior to Migration
Process
Data is crucial Don’t rush it
Encryption and
Decryption.
Understand the
framework
Prepare
Automated Test
Framework.
Did you made
security policies

4. Deciding On When to Go for Mule 3 To
Mule 4 Migration
• Organizationalreadiness
• Are MuleSoftexpertsfully trained and skilled in using Mule 4?
• Learn howthe componentsworkin Mule 4 to see what has changed
fromMule 3
• Is yourorganization willing to keep all MuleSoftsupported
applicationsup to date with Mule 4 upgrades?
• Is Mule 3 and its variantslicense expiring?
• Is customer/clientwantingto upgradeall their applicationsto Mule
4?
• Environmentsetup for migration

5. Mule4 Vs Mule3 Release,Why
Upgrade?
• Integrated and Effective Error handling
• Better Application Configuration: Maven
• Simplified Event Processing and
Messaging
• DataWeave 2.0 For Better Data Handling

6. Conducting
Mule 3 to
Mule 4
Migration
Process
Migrate Patterns
Migrate Water marks
Migrate Core components
Migrate Connectors
Custom Connector from 3.x to 4.x

7. Migrate Patterns
Migrate message properties
Invocation Properties
Invocation properties are now called variables in Mule 4. Behavior is exactly the same as in
Mule 3.
Inbound Properties, Outbound Properties, Inbound and Outbound Attachments
These scopes do not exist in Mule 4.
Migration re-connection strategies - reconnection hasn’t changed much between Mule 3 and Mule 4
In Mule 3, reconnection strategies were specified on each connector’s config element. These strategies had
two purposes:
> To reconnect when a running application looses connection to an endpoint
> To validate all connections when the application is being deployed.
In Mule 4 you can simply specify if deployment should fail or not if connectivity testing fails

8. Migrate
Water marks
Watermarking is
typically usedto
perform data
synchronization
<flow name="syncWithWatermark" processingStrategy="synchronous">
<poll>
<fixed-frequency-scheduler frequency="1" timeUnit="HOURS" />
<watermark variable="timestamp"
default-expression="#[server.dateTime.format(&quot;yyyy-MM-dd'T'HH:mm:ss.SSS'Z'&quot;)]"
selector="MAX"
selector-expression="#[payload.LastModifiedDate]" />
<sfdc:queryconfig-ref="Salesforce" query="select Id,LastModifiedDate fromContact where LastModifiedDate &amp;gt;
#[flowVars['timestamp']]" />
</poll>
<flow-ref name="doYourSyncMagic"/>
</flow>
<os:object-store name="watermarkStore"persistent="true"/>
<flow name="watermark">
<os:retrieve key="watermark" objectStore="watermarkStore"target="watermark">
<os:default-value>2017-09-11T00:00:00.000Z</os:default-value>
</os:retrieve>
<sfdc:query config-ref="config">
<sfdc:salesforce-query>
<![CDATA[ #["Select Id, Name, BillingCity,Phone,Website,LastModifiedDate from account WHERE LastModifiedDate > " ++ vars.watermark]
]]>
</sfdc:salesforce-query>
</sfdc:query>
<flow-ref name="doYourIntegrationLogic"/>
<os:store key="watermark" failIfPresent="false" failOnNullValue="false"objectStore="watermarkStore">
<os:value>#[max(payload map $.LastModifiedDate)]</os:value>
</os:store>
• Mule 4
• Mule 3

9. Automatic
Watermark
• File, Ftp, Sftp, Database and Salesforce connectors have
this capability of doing automatic watermarking
<flow name="onNewInvoice">
<file:listener config-ref="file" directory="invoices"
autoDelete="false" watermarkMode="CREATED_TIMESTAMP">
<scheduling-strategy>
<fixed-frequency frequency="1000"/>
</scheduling-strategy>
</file:listener>
<flow-ref name="onNewInvoice"/>
</flow>

10. Batch componentsMigrate
ChoicerouterMigrate
Exceptionstrategiesto error handlersMigrate
Enricherstoo targetparametersMigrate
FiltersMigrate
The "For Each" componentMigrate
Poll componentMigrate
Scatter-GatherRouterMigrate
TransformersMigrate
Migrate Core components

11. Migrate
Connectors
Anypoint
EnterpriseSecurity
(AES) Module
AMQP Connector
Database
Connector
Email Connector File Connector
FTP and SFTP
Connector
HTTP Connector
JMS Connector
Object Store
Connector
Scripting Module
Spring Module
Validate Module VM Module
Web Service
Consumer Module
XML Module

12. MuleSoft
Connector
Migration
from 3.x to 4.x
MuleSoft connector architectureis completely
changed in Mule 4.x. In Mule 3.x.
Dev-Kit is used to develop the connector.
In Mule 4, it is based on Mule4 SDK.
Here each processor displayed as a separate
connector in Anypoint Studio Pallet.

13. To Migrate
the connector
to Mule 4,
you can use
conversion
tool
Enable the Connector
as Mule 4 extensionin
pom file
Modify Package element:
<packaging>
mule-extension
</packaging>
Modify parent element
< parent>
<groupId>org.mule.extensions</groupId>
<artifactId>mule-modules-
parent</artifactId>
<version>1.0.0</version>
</parent>
Modify the Folder structure
The typical folder structure
for Mule 4 is
<Module>/api
<Module>/internal
UpdateAnnotations
and ParamsClasses
Delete/Add/UpdateClasses based
on Mule 4 SDK (Please refer Java
Docs)

14. Your Best
Friend in
MIGRATION!
• https://docs.mulesoft.com/mule-
runtime/4.2/migration-process
• https://docs.mulesoft.com/mule-
runtime/4.2/migration-dataweave
• https://docs.mulesoft.com/mule-
runtime/4.2/migration-mel
Migration Documentation
• https://docs.mulesoft.com/mule-
runtime/4.2/migration-prep
Migration Preparation
• https://docs.mulesoft.com/mule-
runtime/4.2/migration-cheat-sheet
Mule 3 to Mule 4 migration cheat sheet

15. Your Best
Friend in
MIGRATION!
• https://docs.mulesoft.com/mule-runtime/4.2/migration-process
• https://docs.mulesoft.com/mule-runtime/4.2/migration-
dataweave
• https://docs.mulesoft.com/mule-runtime/4.2/migration-mel
Migration Documentation
• https://docs.mulesoft.com/mule-runtime/4.2/migration-prep
Migration Preparation
• https://docs.mulesoft.com/mule-runtime/4.2/migration-cheat-
sheet
Mule 3 to Mule 4 migration cheat sheet

16. THANK YOU!