Refactored how headers are generated to allow for easier schema consistency checking, will continue on this tomorrow

Author: mrodrig

lib/converter.js

@@ -4,7 +4,9 @@ var json2Csv = require('./json-2-csv'), // Require our json-2-csv code
     csv2Json = require('./csv-2-json'), // Require our csv-2-json code
     _ = require('underscore'); // Require underscore
 
-// Default options; By using a function this is essentially a 'static' variable
+/**
+ * Default options
+ */
 var defaultOptions = {
     DELIMITER         : {
         FIELD  :  ',',
@@ -15,16 +17,19 @@ var defaultOptions = {
     PARSE_CSV_NUMBERS : false
 };
 
-// Build the options to be passed to the appropriate function
-// If a user does not provide custom options, then we use our default
-// If options are provided, then we set each valid key that was passed
+/**
+ * Build the options to be passed to the appropriate function
+ * If a user does not provide custom options, then we use our default
+ * If options are provided, then we set each valid key that was passed
+ */
 var buildOptions = function (opts, cb) {
-    opts = opts ? opts : {}; // If undefined, set to an empty doc
-    var out = _.defaults(opts, defaultOptions);
+    opts = _.defaults(opts || {}, defaultOptions);
+    // Note: _.defaults does a shallow default, we need to deep copy the DELIMITER object
+    opts.DELIMITER = _.defaults(opts.DELIMITER || {}, defaultOptions.DELIMITER);
     // If the delimiter fields are the same, report an error to the caller
-    if (out.DELIMITER.FIELD === out.DELIMITER.ARRAY) { return cb(new Error('The field and array delimiters must differ.')); }
+    if (opts.DELIMITER.FIELD === opts.DELIMITER.ARRAY) { return cb(new Error('The field and array delimiters must differ.')); }
     // Otherwise, send the options back
-    else { return cb(null, out); }
+    else { return cb(null, opts); }
 };
 
 // Export the following functions that will be client accessible

lib/json-2-csv.js

@@ -3,38 +3,49 @@
 var _ = require('underscore'),
     async = require('async');
 
-var options = {}; // Initialize the options - this will be populated when the csv2json function is called.
-
-// Takes the parent heading and this doc's data and creates the subdocument headings (string)
-var retrieveSubHeading = function (heading, data) {
-    var subKeys = _.keys(data), // retrieve the keys from the current document
-        newKey; // temporary variable to aid in determining the heading - used to generate the 'nested' headings
-    _.each(subKeys, function (subKey, indx) {
-        // If the given heading is empty, then we set the heading to be the subKey, otherwise set it as a nested heading w/ a dot
-        newKey = heading === '' ? subKey : heading + '.' + subKey;
-        if (_.isObject(data[subKey]) && !_.isNull(data[subKey]) && _.isUndefined(data[subKey].length) && _.keys(data[subKey]).length > 0) { // If we have another nested document
-            subKeys[indx] = retrieveSubHeading(newKey, data[subKey]); // Recur on the subdocument to retrieve the full key name
-        } else {
-            subKeys[indx] = (options.DELIMITER.WRAP || '') + (newKey || '') + (options.DELIMITER.WRAP || ''); // Set the key name since we don't have a sub document
-        }
-    });
-    return subKeys.join(options.DELIMITER.FIELD); // Return the headings joined by our field delimiter
-};
+var options = {}; // Initialize the options - this will be populated when the json2csv function is called.
 
 // Retrieve the headings for all documents and return it.  This checks that all documents have the same schema.
-var retrieveHeading = function (data, cb) {
-    var keys = _.keys(data); // Retrieve the current data keys
-    _.each(keys, function (key, indx) { // for each key
+var generateHeading = function(data, cb) {
+    var keys = _.map(_.keys(data), function (key, indx) { // for each key
         if (_.isObject(data[key])) {
             // if the data at the key is a document, then we retrieve the subHeading starting with an empty string heading and the doc
-            keys[indx] = retrieveSubHeading('', data[key]);
+            return generateSubHeading('', data[key]);
         }
+        return key;
+    });
+
+    // TODO: check for consistent schema
+
+    keys = _.map(keys, function(keyList) {
+        return _.flatten(keyList).join(options.DELIMITER.FIELD);
     });
+
     // Retrieve the unique array of headings (keys)
     keys = _.uniq(keys);
+
     // If we have more than 1 unique list, then not all docs have the same schema - report an error
     if (keys.length > 1) { throw new Error('Not all documents have the same schema.', keys); }
-    return cb(null, _.flatten(keys).join(options.DELIMITER.FIELD)); // Return headings back
+
+    return cb(null, keys);
+};
+
+// Takes the parent heading and this doc's data and creates the subdocument headings (string)
+var generateSubHeading = function(heading, data) {
+    var subKeys, // retrieve the keys from the current document
+        newKey = ''; // temporary variable to aid in determining the heading - used to generate the 'nested' headings
+
+    subKeys = _.map(_.keys(data), function (subKey) {
+        // If the given heading is empty, then we set the heading to be the subKey, otherwise set it as a nested heading w/ a dot
+        newKey = heading === '' ? subKey : heading + '.' + subKey;
+        if (_.isObject(data[subKey]) && !_.isNull(data[subKey]) && _.isUndefined(data[subKey].length) && _.keys(data[subKey]).length > 0) { // If we have another nested document
+            return generateSubHeading(newKey, data[subKey]); // Recur on the sub-document to retrieve the full key name
+        } else {
+            return options.DELIMITER.WRAP + newKey + options.DELIMITER.WRAP; // Set the key name since we don't have a sub document
+        }
+    });
+
+    return subKeys; // Return the headings joined by our field delimiter
 };
 
 // Convert the given data with the given keys
@@ -71,17 +82,17 @@ module.exports = {
     // Takes options as a document, data as a JSON document array, and a callback that will be used to report the results
     json2csv: function (opts, data, callback) {
         if (!callback) { throw new Error('A callback is required!'); } // If a callback wasn't provided, throw an error
-        if (!opts) { callback(new Error('Options were not passed and are required.')); return null; } // Shouldn't happen, but just in case
+        if (!opts) { return callback(new Error('Options were not passed and are required.')); } // Shouldn't happen, but just in case
         else { options = opts; } // Options were passed, set the global options value
-        if (!data) { callback(new Error('Cannot call json2csv on ' + data + '.')); return null; } // If we don't receive data, report an error
+        if (!data) { return callback(new Error('Cannot call json2csv on ' + data + '.')); } // If we don't receive data, report an error
         if (!_.isObject(data)) { // If the data was not a single document or an array of documents
-            return cb(new Error('Data provided was not an array of documents.'));  // Report the error back to the caller
+            return callback(new Error('Data provided was not an array of documents.'));  // Report the error back to the caller
         } else if (_.isObject(data) && !data.length) { // Single document, not an array
             data = [data]; // Convert to an array of the given document
         }
 
         // Retrieve the heading and the CSV asynchronously in parallel
-        async.parallel([_.partial(retrieveHeading, data), _.partial(generateCsv, data)], function (err, res) {
+        async.parallel([_.partial(generateHeading, data), _.partial(generateCsv, data)], function (err, res) {
             if (!err) {
                 // Data received with no errors, join the two responses with an end of line delimiter to setup heading and CSV body
                 return callback(null, res.join(options.EOL));