Format your JSONata expressions using Prettier.

A Prettier plugin must first parse the source code of the target language into a traversable data structure (Usually an Abstract Syntax Tree) and then print out that data structure in a "pretty" style.

prettier-plugin-jsonata uses the JSONata parser available as part of the jsonata package.

• The plugin supports all JSONata feature up to 1.8.6 version, and is backward compatible with 1.7.0 release.
• The plugin can output formatted code for any AST node type.
• Only printWidth, tabWidth, and useTabs formatting options are supported.
• Native integration with code editors is not supported due to the lack of IDE extensions providing JSONata language support. Once such extensions are available, it should become possible to format JSONata documents on save when this plugin is installed.

# Install locally in a project
npm install --save-dev @stedi/prettier-plugin-jsonata prettier

# Or globally
npm install -g @stedi/prettier-plugin-jsonata prettier

Once you installed prettier and prettier-plugin-jsonata as dev dependencies in your project, you can format your code using Prettier CLI.

npx prettier --write ./**/*.jsonata

You can format your JSONata expressions using Prettier's own format method like this:

import * as prettier from "prettier";
import * as prettierPlugin from "@stedi/prettier-plugin-jsonata";

const expression = "($myVar:=foo.bar[]; $reverse($myVar))";
const formattedExpression = prettier.format(expression, {
  parser: prettierPlugin.AST_PARSER_NAME,
  plugins: [prettierPlugin],
  printWidth: 150,
  tabWidth: 2,
  useTabs: false,
});

console.log(formattedExpression);

Alternatively, you can use the formatJsonata function:

import { formatJsonata } from "@stedi/prettier-plugin-jsonata/dist/lib";

const expression = "($myVar:=foo.bar[]; $reverse($myVar))";
const formattedExpression = formatJsonata(expression);

console.log(formattedExpression);

If you parse JSONata as part of your business logic and only need to print JSONata AST tree as a formatted string, you can use serializeJsonata function:

import jsonata from "jsonata";
import { serializeJsonata } from "@stedi/prettier-plugin-jsonata/dist/lib";

const jsonataAST = jsonata("($myVar:=foo.bar[]; $reverse($myVar))").ast();
const formattedExpression = serializeJsonata(jsonataAST);

console.log(formattedExpression);