Add option includeEmptyRows, defaults to false #120

README.md

@@ -63,6 +63,7 @@ or [use it from the CLI](https://github.com/zemirco/json2csv#command-line-interf
   - `newLine` - String, overrides the default OS line ending (i.e. `\n` on Unix and `\r\n` on Windows).
   - `flatten` - Boolean, flattens nested JSON using [flat]. Defaults to `false`.
   - `excelStrings` - Boolean, converts string data into normalized Excel style data.
+  - `includeEmptyRows` - Boolean, includes empty rows. Defaults to `false`.
 - `callback` - **Required**; `function (error, csvString) {}`. To create a promise, you can use `var toCSV = Bluebird.promisify(json2csv)`, see [Bluebird] docs.
 
 #### Example `fields` option

index.d.ts

@@ -18,12 +18,13 @@ declare namespace json2csv {
     newLine?: string;
     flatten?: boolean;
     excelStrings?: boolean;
+    includeEmptyRows?: boolean;
   }
 
   interface ICallback {
     (error: Error, csv: string): void;
   }
-  
+
   export function json2csv(options: IOptions, callback: ICallback): string;
 }
 

lib/json2csv.js

@@ -91,6 +91,9 @@ function checkParams(params, callback) {
   //#check hasCSVColumnTitle, if it is not explicitly set to false then true.
   params.hasCSVColumnTitle = params.hasCSVColumnTitle !== false;
 
+  //#check include empty rows, defaults to false
+  params.includeEmptyRows = params.includeEmptyRows || false;
+
   callback(null);
 }
 
@@ -150,8 +153,8 @@ function replaceQuotationMarks(stringifiedElement, quotes) {
  */
 function createColumnContent(params, str) {
   params.data.forEach(function (dataElement) {
-    //if null or empty object do nothing
-    if (dataElement && Object.getOwnPropertyNames(dataElement).length > 0) {
+    //if null do nothing, if empty object without includeEmptyRows do nothing
+    if (dataElement && (Object.getOwnPropertyNames(dataElement).length > 0 || params.includeEmptyRows)) {
       var line = '';
       var eol = params.newLine || os.EOL || '\n';
 

test/fixtures/csv/emptyRow.csv

@@ -0,0 +1,5 @@
+"carModel","price","color"
+"Audi",0,"blue"
+,,
+"Mercedes",20000,"yellow"
+"Porsche",30000,"green"

test/fixtures/csv/emptyRowDefaultValues.csv

@@ -0,0 +1,5 @@
+"carModel","price","color"
+"Audi",0,"blue"
+"NULL",1,"NULL"
+"Mercedes",20000,"yellow"
+"Porsche",30000,"green"

test/fixtures/csv/emptyRowNotIncluded.csv

@@ -0,0 +1,4 @@
+"carModel","price","color"
+"Audi",0,"blue"
+"Mercedes",20000,"yellow"
+"Porsche",30000,"green"

test/fixtures/json/emptyRow.json

@@ -0,0 +1,6 @@
+[
+  { "carModel": "Audi",      "price": 0,  "color": "blue" },
+  {},
+  { "carModel": "Mercedes",  "price": 20000,  "color": "yellow" },
+  { "carModel": "Porsche",   "price": 30000,  "color": "green" }
+]

test/helpers/load-fixtures.js

@@ -25,6 +25,9 @@ var fixtures = [
   'excelStrings',
   'newLineCellContent',
   'overriddenDefaultValue',
+  'emptyRow',
+  'emptyRowNotIncluded',
+  'emptyRowDefaultValues',
 ];
 
 /*eslint-disable no-console*/

test/index.js

@@ -13,6 +13,7 @@ var jsonDefaultValueEmpty = require('./fixtures/json/defaultValueEmpty');
 var jsonTrailingBackslash = require('./fixtures/json/trailingBackslash');
 var jsonNewlines = require('./fixtures/json/newlines');
 var jsonOverriddenDefaultValue = require('./fixtures/json/overridenDefaultValue');
+var jsonEmptyRow = require('./fixtures/json/emptyRow');
 var csvFixtures = {};
 
 async.parallel(loadFixtures(csvFixtures), function (err) {
@@ -448,4 +449,129 @@ async.parallel(loadFixtures(csvFixtures), function (err) {
       t.end();
     });
   });
+
+  test('should include empty rows when options.includeEmptyRows is true', function (t) {
+    json2csv({
+      data: jsonEmptyRow,
+      fields: [
+        {
+          value: 'carModel',
+        },
+        {
+          label: 'price',
+          value: function (row) {
+            return row.price;
+          },
+        },
+        {
+          label: 'color',
+          value: function (row) {
+            return row.color;
+          },
+        }
+      ],
+      includeEmptyRows: true,
+    }, function (error, csv) {
+      t.error(error);
+      t.equal(csv, csvFixtures.emptyRow);
+      t.end();
+    });
+  });
+
+  test('should not include empty rows when options.includeEmptyRows is false', function (t) {
+    json2csv({
+      data: jsonEmptyRow,
+      fields: [
+        {
+          value: 'carModel',
+        },
+        {
+          label: 'price',
+          value: function (row) {
+            return row.price;
+          },
+        },
+        {
+          label: 'color',
+          value: function (row) {
+            return row.color;
+          },
+        }
+      ],
+      includeEmptyRows: false,
+    }, function (error, csv) {
+      t.error(error);
+      t.equal(csv, csvFixtures.emptyRowNotIncluded);
+      t.end();
+    });
+  });
+
+  test('should not include empty rows when options.includeEmptyRows is not specified', function (t) {
+    json2csv({
+      data: jsonEmptyRow,
+      fields: [
+        {
+          value: 'carModel',
+        },
+        {
+          label: 'price',
+          value: function (row) {
+            return row.price;
+          },
+        },
+        {
+          label: 'color',
+          value: function (row) {
+            return row.color;
+          },
+        }
+      ],
+    }, function (error, csv) {
+      t.error(error);
+      t.equal(csv, csvFixtures.emptyRowNotIncluded);
+      t.end();
+    });
+  });
+
+  test('should include empty rows when options.includeEmptyRows is true, with default values', function (t) {
+    json2csv({
+      data: jsonEmptyRow,
+      fields: [
+        {
+          value: 'carModel',
+        },
+        {
+          label: 'price',
+          value: function (row) {
+            return row.price;
+          },
+          default: 1
+        },
+        {
+          label: 'color',
+          value: function (row) {
+            return row.color;
+          },
+        }
+      ],
+      defaultValue: 'NULL',
+      includeEmptyRows: true,
+    }, function (error, csv) {
+      t.error(error);
+      t.equal(csv, csvFixtures.emptyRowDefaultValues);
+      t.end();
+    });
+  });
+
+  test('should parse data:[null] to csv with only column title, despite options.includeEmptyRows', function (t) {
+    json2csv({
+      data: [null],
+      fields: ['carModel', 'price', 'color'],
+      includeEmptyRows: true,
+    }, function (error, csv) {
+      t.error(error);
+      t.equal(csv, '"carModel","price","color"');
+      t.end();
+    });
+  });
 });