# prettyjson.js

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Package for formatting JSON data in a coloured YAML-style, perfect for CLI output

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### Export package

    module.exports = exports;

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### Module dependencies

    var colors = require('colors');
    var Utils  = require('./utils');
    var fs = require('fs');

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### Package version

    exports.version = JSON.parse(fs.readFileSync(__dirname + '/../package.json', 'utf8')).version;

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### Render function

Parameters:

- `data`: Data to render
- `options`: Hash with different options to configure the parser
- `indentation`: Base indentation of the parsed output

Example of options hash:

    {
      emptyArrayMsg: '(empty)', // Rendered message on empty strings
      keysColor: 'blue',        // Color for keys in hashes
      dashColor: 'red',         // Color for the dashes in arrays
      stringColor: 'grey',      // Color for strings
      defaultIndentation: 2     // Indentation on nested objects
    }

    exports.render = function render(data, options, indentation) {
      "use strict";

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Default value for the indentation param

      indentation = indentation || 0;

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Default values for the options

      options = options || {};
      options.emptyArrayMsg = options.emptyArrayMsg || '(empty array)';
      options.keysColor = options.keysColor || "green";
      options.dashColor = options.dashColor || "green";
      options.defaultIndentation = options.defaultIndentation || 2;

      options.stringColor = options.stringColor || null;

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Initialize the output (it's an array of lines)

      var output = [];

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Helper function to detect if an object can be serializable directly

      var isSerializable = function(input) {
        if (typeof input === 'string' || typeof input === 'boolean' ||
            typeof input === 'number' || input === null) {
          return true;
        }
        return false;
      };

      var addColorToData = function(input) {
        if (typeof input === 'string') {

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Print strings in regular terminal color

          return options.stringColor ? input[options.stringColor] : input;
        }

        if (input === true) {
          return (input+'').green;
        }
        if (input === false) {
          return (input+'').red;
        }
        if (input === null) {
          return (input+'').grey;
        }
        if (typeof input === 'number') {
          return (input+'').blue;
        }
        return (input+'');
      };

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Render a string exactly equal

      if (isSerializable(data)) {
        output.push(Utils.indent(indentation) + addColorToData(data));
      }
      else if (Array.isArray(data)) {

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If the array is empty, render the `emptyArrayMsg`

        if (data.length === 0) {
          output.push(Utils.indent(indentation) + options.emptyArrayMsg);
        } else {
          data.forEach(function(element) {

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Prepend the dash at the begining of each array's element line

            var line = Utils.indent(indentation) + ('- ')[options.dashColor];

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If the element of the array is a string, render it in the same line

            if (typeof element === 'string') {
              line += exports.render(element, options);
              output.push(line);

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If the element of the array is an array or object, render it in next line

            } else {
              output.push(line);
              output.push(
                exports.render(element, options, indentation + options.defaultIndentation)
              );
            }
          });
        }
      }
      else if (typeof data === 'object') {

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Get the size of the longest index to render all the values on the same column

        var maxIndexLength = Utils.getMaxIndexLength(data);
        var key;

        for(var i in data) {

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Prepend the index at the beginning of the line

          key = Utils.indent(indentation) + (i + ': ')[options.keysColor];

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If the value is serializable, render it in the same line

          if (isSerializable(data[i])) {
            key += exports.render(data[i], options, maxIndexLength - i.length);
            output.push(key);

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If the index is an array or object, render it in next line

          } else {
            output.push(key);
            output.push(
              exports.render(data[i], options, indentation + options.defaultIndentation)
            );
          }
        }
      }

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Return all the lines as a string

      return output.join('\n');
    };

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### Render from string function

Parameters:

- `data`: Data to render as a string
- `options`: Hash with different options to configure the parser
- `indentation`: Base indentation of the parsed output

Example of options hash:

    {
      emptyArrayMsg: '(empty)', // Rendered message on empty strings
      keysColor: 'blue',        // Color for keys in hashes
      dashColor: 'red',         // Color for the dashes in arrays
      defaultIndentation: 2     // Indentation on nested objects
    }

    exports.renderString = function renderString(data, options, indentation) {
      "use strict";

      var output = '';
      var parsedData;

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If the input is not a string or if it's empty, just return an empty string

      if (typeof data !== 'string' || data === '') {
        return '';
      }

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Remove non-JSON characters from the beginning string

      if (data[0] !== '{' && data[0] !== '[') {
        var beginingOfJson;
        if (data.indexOf('{') === -1) {
          beginingOfJson = data.indexOf('[');
        } else if (data.indexOf('[') === -1) {
          beginingOfJson = data.indexOf('{');
        } else {
          beginingOfJson = data.indexOf('{') < data.indexOf('[') ? data.indexOf('{') : data.indexOf('[');
        }
        output += data.substr(0, beginingOfJson) + "\n";
        data = data.substr(beginingOfJson);
      }

      try {
        parsedData = JSON.parse(data);
      } catch (e) {

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Return an error in case of an invalid JSON

        return 'Error:'.red + ' Not valid JSON!';
      }

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Call the real render() method

      output += exports.render(parsedData, options);
      return output;
    };