fsnip/dist/jsonSnip.js

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

'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.json = json;
exports.jsonPrettify = jsonPrettify;
exports.jsonEllipsify = jsonEllipsify;
exports.minimizeJsonProperty = minimizeJsonProperty;
exports.jsonSnippet = jsonSnippet;
exports.jsonDelKeys = jsonDelKeys;
var jp = require('jsonpath');

var _require = require('./commonFuncs.js'),
    setInputType = _require.setInputType,
    removeQuotes = _require.removeQuotes;

function buildJsonSearchPath(keyName) {
  if (keyName.substr(0, 1) === '$') {
    return keyName;
  } else {
    return "$..['" + keyName + "']";
  }
}

// =================json===============================
function json(inpObj) {
  // cmdArgs is an array of arguments
  // json is an object containing the json object we need to modify
  setInputType(inpObj, 'json'); // all we do is flag our content as being json
}

// =================jsonPrettify=======================
function jsonPrettify(inpObj, cmdArgs) {
  // cmdArgs is an (optional) array of arguments being indent, maxLength, margins
  // they are all passed as strings so need to be converted to numbers where appropriate
  // we use - 0 to convert string numbers to numeric and === against itself to check for NaN
  if (setInputType(inpObj, 'json')) {
    var opts = inpObj.outputOptions;
    // set defaults
    opts.margins = false;
    opts.maxLength = 45;
    opts.indent = 2;
    // overwrite with any values passed in
    if (cmdArgs !== undefined) {
      if (typeof (cmdArgs[0] - 0) === 'number' && !isNaN(cmdArgs[0] - 0)) {
        opts.indent = cmdArgs[0] - 0;
      }
      if (typeof (cmdArgs[1] - 0) === 'number' && !isNaN(cmdArgs[1] - 0)) {
        opts.maxLength = cmdArgs[1] - 0;
      }
      if (cmdArgs[1] === 'infinity') {
        opts.maxLength = 'infinity';
      }
      opts.margins = cmdArgs[2] === 'true'; // defaults to false if margins anything other than true
    }
  }
}

// =================ellipsify==========================
function jsonEllipsify(inpObj, cmdArgs) {
  // cmdArgs is an array of arguments
  // json is an object containing the json object we need to modify

  if (setInputType(inpObj, 'json')) {
    // we have two types of argument for Ellipsify, plain and exclude so separate them out
    var cmdArgsPlain = [];
    var cmdArgsExclude = [];
    for (var i = 0; i < cmdArgs.length; i++) {
      if (cmdArgs[i].substr(0, 1) === '~') {
        cmdArgsExclude.push(removeQuotes(cmdArgs[i].substr(1)));
      } else {
        cmdArgsPlain.push(removeQuotes(cmdArgs[i]));
      }
    }
    if (cmdArgsPlain.length === 0) {
      cmdArgsPlain.push('$');
    }
    for (var _i = 0; _i < cmdArgsPlain.length; _i++) {
      minimizeJsonProperty(inpObj.json, cmdArgsPlain[_i], cmdArgsExclude);
    }
  }
}

function minimizeJsonProperty(json, property, excludes) {
  // only exported for test purposes
  // this function takes a json object as input.and for every occurrence of the given property puts a placeholder
  // but only if it is an array or an object.
  var arrPlaceholder = ['fsnipPlaceholderArrEllipses']; // a valid json array used as a placeholder to be replaced later with [...] (which is not valid json)
  var strPlaceholder = 'fsnipPlaceholderStrEllipses';
  var jsonPaths = jp.paths(json, buildJsonSearchPath(property)); // creates an array of all the paths of instances of the the property we want to minimize
  for (var i = 0; i < jsonPaths.length; i++) {
    var jsonPath = jp.stringify(jsonPaths[i]);
    switch (jp.value(json, jsonPath).constructor.name) {
      case 'Object':
        delKeys(json, jsonPath, excludes);
        jp.value(json, jsonPath)['fsnipPlaceholderObj'] = 'Ellipses'; // add a placeholder for the Ellipses
        break;
      case 'Array':
        jp.value(json, jsonPath, arrPlaceholder);
        break;
      case 'String':
        jp.value(json, jsonPath, strPlaceholder);
        break;
      default:
      // do nothing
    }
  }

  function delKeys(json, jsonPath, excludes) {
    var keys = Object.keys(jp.value(json, jsonPath));
    for (var j = 0; j < keys.length; j++) {
      if (excludes.indexOf(keys[j]) === -1) {
        // this key is not in the excludes list so we need to delete it
        delete jp.value(json, jsonPath)[keys[j]];
      }
    }
  }
}

// ===================snip Function==============================
function jsonSnippet(inpObj, cmdArgs) {
  // cmdArgs is an array of arguments
  // inpObj is an object containing the json object we need to modify
  // the format of the call is eg.
  // '--snip vessel 2' which would extract the second instance of "vessel" in the json supplied
  // with the instance identifier being optional
  if (setInputType(inpObj, 'json')) {
    var occ = 1;
    if (cmdArgs.length === 1) {
      occ = 1; // by default we snip the first occurrence of this property
    } else if (cmdArgs.length === 2) {
      if (typeof (cmdArgs[1] - 0) === 'number' && !isNaN(cmdArgs[1] - 0)) {
        occ = cmdArgs[1] - 0;
        if (occ < 1) {
          inpObj.error.push('--snip requires its second argument to be a numeric values of at least 1 being the instance required');
          return;
        }
      } else {
        inpObj.error.push("--snip requires its second argument to be numeric eg. '--snip vessel 2' with the optional second argument being the instance required");
        return;
      }
    } else {
      inpObj.error.push("--snip requires 1 or 2 arguments eg. '--snip vessel 2' with the optional second argument being the instance required.");
      return;
    }
    var jsonPaths = jp.paths(inpObj.json, buildJsonSearchPath(removeQuotes(cmdArgs[0]))); // creates an array of all the paths to this property
    if (jsonPaths.length < occ) {
      inpObj.error.push('--snip failed because there were only ' + jsonPaths.length + " occurrences of '" + removeQuotes(cmdArgs[0]) + "' found.");
      return;
    }
    inpObj.json = jp.value(inpObj.json, jp.stringify(jsonPaths[occ - 1]));
  }
}

// ===================delKeys Function===========================
function jsonDelKeys(inpObj, cmdArgs) {
  // cmdArgs is an array of arguments
  // inpObj is an object containing the json object we need to remove keys from
  // the format of the call is eg.
  // '-jsonDelKeys vessel gnss' which would delete all instances of "vessel" and "gnss" in the json supplied
  if (setInputType(inpObj, 'json')) {
    for (var i = 0; i < cmdArgs.length; i++) {
      deleteJsonKey(inpObj.json, removeQuotes(cmdArgs[i]));
    }
  }
}

function deleteJsonKey(json, key) {
  // deletes all occurrences of key within json
  var jsonPaths = jp.paths(json, buildJsonSearchPath(key)); // creates an array of all the paths of instances of the key we want to delete
  var parent;
  for (var i = 0; i < jsonPaths.length; i++) {
    var jsonPath = jp.stringify(jsonPaths[i]);
    parent = jp.parent(json, jsonPath);
    if (Array.isArray(parent)) {
      parent.splice(jsonPaths[i][jsonPaths[i].length - 1], 1);
    } else {
      delete parent[jsonPaths[i][jsonPaths[i].length - 1]];
    }
  }
}