Learn MuleSoft from beginner to

1. Message Structure

• Message structure between Mule 3 and Mule 4

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• Mule 4
  Mule Event = Mule Message + Variables
  Mule Message = Payload + Attributes

MULE 4 - Message Structure

• Payload

  It's the actual message content. Payload can be overridden.

• Attributes

They provides meta data such as: queryParams, file size, etc.
They are immutable(can not be changed).

• Variables

  They are something you can store some kind of data or information which can be used across the application as long as you connect the flows with flow-ref.

 

2. Anypoint Studio

It is the graphical IDE you develop mule application.

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3. Mule Project Structure

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• Every project in Mule 4 is a Mavenized Project
• All Mule xmls are placed under src/main/mule
• Other files can be placed under: src/main/resources or src/test/resources
• mule-artifact.json
• Each Mule app xml includes:
  Message Flow(Graphical view)
  Global Elements(contains all config details)
  Configuration XML(xml version of graphical view)

 

4. Flow/Sub Flow/Private Flow

• An app can consist of a single flow
• Or it can break up processing into discrete(private) flows and sub flows that you add to the app and connect together
• Private and sub-flows can be triggered by Flow-reference or by DataWeave lookup

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What is a Flow

• A flow has "Source", "Process" and "Error Handling" parts

  
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What is a Private Flow

• A private flow also has "Source", "Process" and "Error Handling" parts

• But we don't keep anything in "Source" part of a private flow

  
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What is a Sub Flow

• A sub flow does not have "Source" or "Error Handling" parts
• A sub flow has only "Process" art
• "Error Handling" for sub flows are handled by calling flow/private flow

 

5. Connectors

Anypoint Connectors are reusable extensions to Mule runtime engine (Mule) that enable you to integrate a Mule app with third-party APIs, databases, and standard integration protocols. Connectors abstract the technical details involved with connecting to a target system.

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Using connectors in a Mule app provides the following advantages:

• Reduces code complexity, because you can connect a Mule app to a target system without knowing all of the details required to program to the target system

• Simplifies authenticating against the target system

• Proactively infers metadata for the target system, which makes it easier to identify and transform data with DataWeave

• Makes code maintenance easier because:

  a. Not all changes in the target system require changes to the app.

  b. The connector configuration can be updated without requiring updates to other parts of the app.

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Some Commonly Used Connectors:

Http Listener

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• Listens to the request which client/user sends
• Mandatory config details required: host, port, path
• Default: Accepts all kinds of methods if nothing is specified

Config Details Example:

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Set Payload

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• The Set Payload component lets you update the payload of the message
• The payload can be a literal string or a DataWeave expression
• Mandatory config details required: value
  (eg: #["Hello World"] or #[payload] or #[attributes.queryParams.name])

Config Details Example:

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6. Hands On

• 6-1) Create a simple project:

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• 6-2) Drag a flow from Mule Palette into your canvas:

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• 6-3) Drag a http listener from Mule Palette into Source part of your flow:

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• 6-4) Add http listener config and test connection:

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• 6-5) Fill in the path of the listener:

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• 6-6) Drag a Set Payload from Mule Palette into Process part of your flow:

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• 6-7) Set value of the Payload

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