fsnip/dist/helpers.js

Command line utility to extract and modify text or json from a file

'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.cli = cli;
/*
=====fsnip======

fsnip is a command line utility to extract and modify json from a file.

*/
var fs = require('fs');
var os = require('os');
var stringify = require('json-stringify-pretty-compact');
var chalk = require('chalk');

var _require = require('./runOptions.js'),
    runOption = _require.runOption;

function cli(args) {
  if (args.length === 3 && args[2] === '--help') {
    console.info(chalk.cyan('  fsnip is a tool for extracting json or text snippets from files.\n\n') + '  Usage: ' + chalk.whiteBright('fsnip FILE [options [arguments]]\n') + '             ' + chalk.gray('process the file and output the result to the console\n\n') + '  FILE       ' + chalk.gray('specifies the file to process\n') + '  Options:\n' + '     --prettify [indent] [maxLength] [margins]\n' + chalk.grey('             applies prettification to JSON\n') + '     --snip JSONPath\n' + chalk.grey('             snips the key specified by JSONPath\n') + '     --ellipsify JSONPath [JSONPath] ... [~JSONPath] ...\n' + chalk.grey('             replaces the passed json object, array or string with\n' + '             ellipses (...) but excludes any keys which follow\n' + '             prepended by ~\n' + '             eg. fsnip myfile.json --ellipsify $..address ~postcode\n') + '    --delKeys JSONPath [JSONPath] ...\n' + chalk.grey('             deletes the keys following the option\n') + '    --from TEXT\n' + '    --to TEXT\n' + '    --start TEXT\n' + '    --finish TEXT\n' + chalk.grey('             these options work on any plain file extracting the parts of the\n' + '             file after or up to the TEXT specified. --from and --to are\n' + '             exclusive, whereas --start and --finish are inclusive of the TEXT.'));
  } else if (args.length >= 3) {
    try {
      var txt = fs.readFileSync(args[2]).toString();
    } catch (err) {
      console.error(chalk.redBright("unable to read file '" + args[2] + "'"));
    }
    if (typeof txt !== 'undefined') {
      console.info(fsnipDo(args.slice(3), txt));
    }
  } else {
    // we couldn't recognise the format on the command line
    console.error(chalk.redBright('Unrecognised arguments passed to fsnip. See fsnip --help'));
  }
}

function fsnipDo(cmdOpts, inputText) {
  // does the processing of the fsnip command
  // inputText is the text we want to modify
  if (cmdOpts === null || cmdOpts.length === 0) {
    return inputText;
  } // no processing required as no options passed in
  var src = { // a temporary structure containing the text we are working on its type eg. 'json' (which is set later)
    text: inputText,
    type: '',
    outputOptions: {},
    error: [],
    json: null,
    plain: null
  };

  parseOptions();
  postProcess(src);
  return src.error.length === 0 ? src.text : chalk.redBright(src.error);

  function parseOptions() {
    // now we are going to parse through the options and arguments to extract individual options together with their arguments
    var cmdOpt = ''; // current option from the cmdOptsString list
    var cmdArgs = []; // array containing any arguments for the cmdOpt
    for (var i = 0; i < cmdOpts.length; i++) {
      if (cmdOpts[i].substr(0, 2) === '--') {
        // this is a new option eg. --ellipsify
        processOption();
        cmdOpt = cmdOpts[i]; // store the new option we have found
        cmdArgs = []; // reset ready for any new arguments
      } else {
        // this must be an argument for the current option
        if (cmdOpt === '') {
          // error if we don't currently have an option
          src.error.push("invalid argument '" + cmdOpts[i] + "' passed without valid option to fsnip");
        } else {
          cmdArgs.push(cleanCmdOpt(cmdOpts[i]));
        }
      }
    }
    processOption();

    function processOption() {
      // process/run any option we've found
      if (cmdOpt !== '') {
        runOption(cmdOpt, cmdArgs, src);
      }
    }

    function cleanCmdOpt(cmdOpt) {
      // deals with any special characters dealt with for cross platform purposes
      // in windows \$ is replaced with $ as $ is a special character which has to be delimited in posix
      var r = cmdOpt;
      /* istanbul ignore if  */
      if (os.platform() === 'win32') {
        r = r.replace(/\\\$/g, '$');
      }
      return r;
    }
  }
}

function postProcess(inpObj) {
  // does any post process tidying up
  if (inpObj.type === 'json') {
    // stringify as required
    var opts = inpObj.outputOptions;
    if (opts.maxLength === 'infinity' && opts.margins === false) {
      inpObj.text = JSON.stringify(inpObj.json);
    } else if (opts.maxLength === 0 && opts.margins === false) {
      inpObj.text = JSON.stringify(inpObj.json, null, opts.indent);
    } else {
      inpObj.text = stringify(inpObj.json, opts);
    }
    // now replace any placeholders. The placeholders are valid JSON but what we replace them with may not be valid JSON
    inpObj.text = inpObj.text.replace(/\[\s*"fsnipPlaceholderArrEllipses"\s*\]/g, '[...]');
    inpObj.text = inpObj.text.replace(/\{\s*"fsnipPlaceholderObj"\s*:\s*"Ellipses"\s*\}/g, '{...}'); // do this separately to the one below so that if the object is empty it appears all on one line
    inpObj.text = inpObj.text.replace(/"fsnipPlaceholderObj"\s*:\s*"Ellipses"/g, '...');
    inpObj.text = inpObj.text.replace(/"fsnipPlaceholderStrEllipses"/g, '"..."');
  } else if (inpObj.type === 'plain') {
    inpObj.text = inpObj.plain.trim();
  }
}