How to HTML entity encode / decode in ballerina?

Question

Currently I'm having a requirement of HTML entity encode / decode using Ballerina language. However I couldn't find any references for that.

If I have a string as following,

https://spdx.org/licenses/Apache-2.0.html

Expected result would be,

https://spdx.org/licenses/Apache-2.0.html

You can refer to the following screenshot where I have done the same thing using an online tool : https://mothereff.in/html-entities

How can we achieve the above?

Answer 1

There is no direct Ballerina module that provides this functionality. But it can be done using the Java interoperability feature in the Ballerina language.

The StringEscapeUtils class of Apache common-text library can be used for this.

Steps:

1. Create a new Ballerina project using bal new <project name> command.
2. Generate Ballerina bindings for StringEscapeUtils using below command.

bal bindgen -mvn org.apache.commons:commons-text:1.9 org.apache.commons.text.StringEscapeUtils

3. Build the project using bal build command.

4. Write the Ballerina code for encode and decode.

import ballerina/io;
import htmlTest.org.apache.commons.text as text;

public function main() {
    string? decodedText = text:StringEscapeUtils_unescapeHtml3("https://spdx.org/licenses/Apache-2.0.html");
    if decodedText is string {
        io:println(decodedText); //Output : https://spdx.org/licenses/Apache-2.0.html
    } else {
        io:println("Error occured during conversion");
    }
}

For more details refer to the Java interoperability guide on Ballerina.