In this tutorial, we will see how we can use MuleSoft's Dataweave language to read a properties file dynamically.

As a first step, let's create a new Mule project using Anypoint Studio. After creating the project, let's define our code list as follows:

GB=United Kingdom
USA=United State of America
DE=Germany
JPN=Japan
CHN=China

We will name it 'codelist.properties.' Place it under your Mule project 'src/main/resouces' folder.

Next, let's add the properties file in our global configuration. We will add a new property place holder. For this step, go to Global Elements -> Create -> Property Place.

Let's create a flow with an HTTP inbound connector.

We have set the path to be '/country' and Allowed Methods to be 'GET' only. For HTTP Connector configuration, we have used the following settings:

As a next step, let us assume we will get a query parameter named 'code' in our request. We will set that parameter in a local variable named 'countryCode.'

In the final step, lets add a Transform Message component and call the dataweave function 'p.'

We can test the service after deploying the application in Anypoint Studio. You can use a browser or Postman to hit the service.

For request, try any one of the following URL's.

http://localhost:8081/country?code=GB

http://localhost:8081/country?code=USA

http://localhost:8081/country?code=DE

http://localhost:8081/country?code=JPN

The response will come back as follows (based on the code you've sent across as the query parameter):

{
  "country": "United Kingdom"
}

I hope this article helps you understand how to read properties file dynamically using the Mulesoft Dataweave language.