added files

js/util/csv.js

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+/**
+ * Small module for exporting data to CSV.
+ */
+var _ = require('lodash');
+var preconditions = require('preconditions').singleton();
+var moment = require('../../lib/moment/moment');
+
+var logger = require('../util/log.js');
+var config = require('../../config');
+
+
+var COL_DELIMITER = ',';
+var ROW_DELIMITER = '\r\n';
+
+function getValue(obj, property) {
+  if (_.isFunction(property)) {
+    try { 
+      return property(obj);
+    } catch (err) {
+      if (_.isString(err)) return err;
+      return undefined;
+    }
+  }
+  if (!_.isObject(obj)) return undefined;
+  return obj.hasOwnProperty(property) ? obj[property] : undefined;
+};
+
+function formatValue(value, type, format) {
+  if (_.isUndefined(value) || _.isNull(value)) return '';
+
+  var r;
+  switch (type) {
+    default:
+    case 'string':
+      r = value.toString();
+      r.replace('"', '\\"');
+      break;
+    case 'date':
+      r = moment(value).format(format);
+      break;
+    case 'number':
+      r = value.toString();
+      break;
+  }
+
+  // escape when commas in values
+  if (r.indexOf(',') !== -1) {
+    r = '"' + r + '"';
+  }
+  return r;
+};
+
+function getHeader(descriptor) {
+  return _.map(descriptor.columns, function (col) {
+    return col.label || (_.isString(col.property) ? col.property : '') || '';
+  });
+};
+
+function processDataRow(data, descriptor) {
+  return _.map(descriptor.columns, function (col) {
+    var value = getValue(data, col.property);
+    var formatted = formatValue(value, col.type, col.format);
+    return formatted;
+  });
+};
+
+/**
+ * @desc Convert json object to csv based on a descriptor
+ *
+ * @param {array} data - the array of json objects to convert to csv
+ * @param {object} descriptor - an object that parameterizes the conversion
+ * @param {function} cb - called with the resulting csv
+ */
+module.exports.toCsv = function(data, descriptor, cb) {
+  preconditions.shouldBeArray(data);
+  preconditions.shouldBeObject(descriptor);
+  preconditions.shouldBeArray(descriptor.columns);
+  preconditions.shouldBeFunction(cb);
+
+  var colDelimiter = descriptor.colDelimiter || COL_DELIMITER;
+  var rowDelimiter = descriptor.rowDelimiter || ROW_DELIMITER;
+
+  var rows = _.map(data, function (dataRow) {
+    return processDataRow(dataRow, descriptor);
+  });
+
+  var header = getHeader(descriptor);
+  rows.unshift(header);
+
+  var csv = _.reduce(rows, function (memo, row) {
+    return memo + row.join(colDelimiter) + rowDelimiter;
+  }, '');
+
+  return cb(null, csv);
+};

test/util.csv.js

@@ -0,0 +1,166 @@
+'use strict';
+
+var _ = require('lodash');
+var chai = chai || require('chai');
+var sinon = sinon || require('sinon');
+var should = chai.should();
+
+var csv = require('../js/util/csv')
+var moment = require('../lib/moment/moment');
+
+describe('csv utils', function() {
+  it('should convert simple json', function(done) {
+    var data = [
+      { name: 'Lennon John', age: 40, lastLogin: moment(1417608870000), },
+      { name: 'Cobain, Kurt', age: 27, lastLogin: moment('2014-11-01'), },
+    ];
+
+    var descriptor = {
+      columns: [
+        { label: 'Name', property: 'name', type: 'string' },
+        { label: 'Age', property: 'age', type: 'number' },
+        { property: 'lastLogin', type: 'date' },
+      ],
+    };
+
+    csv.toCsv(data, descriptor, function (err, res) {
+      res.should.equal('Name,Age,lastLogin\r\nLennon John,40,2014-12-03T09:14:30-03:00\r\n"Cobain, Kurt",27,2014-11-01T00:00:00-03:00\r\n');
+      done();
+    });
+  });
+  it('should handle empty data', function(done) {
+    var data = [];
+
+    var descriptor = {
+      columns: [
+        { label: 'Name', property: 'name', type: 'string' },
+        { label: 'Age', property: 'age', type: 'number' },
+        { property: 'lastLogin', type: 'date' },
+      ],
+    };
+
+    csv.toCsv(data, descriptor, function (err, res) {
+      res.should.equal('Name,Age,lastLogin\r\n');
+      done();
+    });
+  });
+  it('should handle null row in data', function(done) {
+    var data = [
+      { name: 'John', age: 40 },
+      null,
+      { name: 'Kurt', age: 27 },
+    ];
+
+    var descriptor = {
+      columns: [
+        { label: 'Name', property: 'name', type: 'string' },
+        { label: 'Age', property: 'age', type: 'number' },
+      ],
+    };
+
+    csv.toCsv(data, descriptor, function (err, res) {
+      res.should.equal('Name,Age\r\nJohn,40\r\n,\r\nKurt,27\r\n');
+      done();
+    });
+  });
+  it('should format dates', function(done) {
+    var data = [
+      { name: 'John', age: 40, lastLogin: moment(1417608870000), },
+      { name: 'Kurt', age: 27, lastLogin: moment('2014-11-01'), },
+    ];
+
+    var descriptor = {
+      columns: [
+        { property: 'name', type: 'string' },
+        { property: 'age', type: 'number' },
+        { property: 'lastLogin', type: 'date', format: 'YYYY MM DD' },
+      ],
+    };
+
+    csv.toCsv(data, descriptor, function (err, res) {
+      res.should.equal('name,age,lastLogin\r\nJohn,40,2014 12 03\r\nKurt,27,2014 11 01\r\n');
+      done();
+    });
+  });
+  it('should compute values from function properties', function(done) {
+    var data = [
+      { name: 'John', payments: 400, withdrawals: 300, },
+      { name: 'Kurt', payments: 270.5, withdrawals: 200, },
+    ];
+
+    var descriptor = {
+      columns: [
+        { property: 'name', type: 'string' },
+        { label: 'Balance', property: function (obj) { return obj.payments - obj.withdrawals; }, type: 'number' },
+      ],
+    };
+
+    csv.toCsv(data, descriptor, function (err, res) {
+      res.should.equal('name,Balance\r\nJohn,100\r\nKurt,70.5\r\n');
+      done();
+    });
+  });  
+  it('should not fail on error from calculated values', function(done) {
+    var data = [
+      { name: 'John', error: 0 },
+      { name: 'Kurt', error: 1 },
+    ];
+
+    var descriptor = {
+      columns: [{
+        property: 'name',
+        type: 'string'
+      }, {
+        label: 'Error',
+        property: function(obj) {
+          if (obj.error) {
+            throw 'dummy error';
+          } else {
+            return 'ok';
+          }
+        }
+      }, ],
+    };
+    csv.toCsv(data, descriptor, function (err, res) {
+      res.should.equal('name,Error\r\nJohn,ok\r\nKurt,dummy error\r\n');
+      done();
+    });
+  });  
+  it('should use blank label if label not specified for computed property', function(done) {
+    var data = [
+      { name: 'John', payments: 400, withdrawals: 300, },
+      { name: 'Kurt', payments: 270.5, withdrawals: 200, },
+    ];
+
+    var descriptor = {
+      columns: [
+        { property: 'name', type: 'string' },
+        { property: function (obj) { return obj.payments - obj.withdrawals; }, type: 'number' },
+      ],
+    };
+
+    csv.toCsv(data, descriptor, function (err, res) {
+      res.should.equal('name,\r\nJohn,100\r\nKurt,70.5\r\n');
+      done();
+    });
+  });  
+  it('should handle non existent properties', function(done) {
+    var data = [
+      { name: 'John', age: 40 },
+      { name: 'Kurt', age: 27 },
+    ];
+
+    var descriptor = {
+      columns: [
+        { property: 'name', type: 'string' },
+        { property: 'age', type: 'number' },
+        { property: 'lastLogin', type: 'date', format: 'YYYY MM DD' },
+      ],
+    };
+
+    csv.toCsv(data, descriptor, function (err, res) {
+      res.should.equal('name,age,lastLogin\r\nJohn,40,\r\nKurt,27,\r\n');
+      done();
+    });
+  });  
+});