Merge pull request #175 from josemigallas/issue_168

Allow renaming headers

lib/parser/parser_stream.js

@@ -33,6 +33,7 @@ function ParserStream(options) {
     options.delimiter = delimiter;
     this.parser = createParser(options);
     this._headers = options.headers;
+    this._renameHeaders = options.renameHeaders;
     this._ignoreEmpty = options.ignoreEmpty;
     this._discardUnmappedColumns = options.discardUnmappedColumns;
     this._strictColumnHandling = options.strictColumnHandling;
@@ -114,6 +115,7 @@ extended(ParserStream).extend({
 
     __processHeaders: function (rows, cb) {
         var headers = this._headers,
+            renameHeaders = this._renameHeaders,
             discardUnmappedColumns = this._discardUnmappedColumns,
             strictColumnHandling = this._strictColumnHandling,
             self = this;
@@ -142,7 +144,7 @@ extended(ParserStream).extend({
                     }
                     while (++i < headersLength) {
                         if (isUndefined(headers[i])) {
-                          continue;
+                            continue;
                         }
                         val = data[i];
                         ret[headers[i]] = isUndefined(val) ? '' : val;
@@ -155,7 +157,14 @@ extended(ParserStream).extend({
             cb(null);
         }
 
-        if (extended.isBoolean(headers) && headers) {
+        if (renameHeaders) {
+            if (Array.isArray(headers)) {
+                rows.shift();
+                headerHandler(null, headers);
+            } else {
+                self.emit("error", new Error("Error renaming headers: new headers must be provided in an array"));
+            }
+        } else if (extended.isBoolean(headers) && headers) {
             this.__handleLine(rows.shift(), 0, true, headerHandler);
         } else {
             headerHandler(null, headers);
@@ -198,9 +207,9 @@ extended(ParserStream).extend({
         // Catches EFBBBF (UTF-8 BOM) because the buffer-to-string
         // conversion translates it to FEFF (UTF-16 BOM)
         if (data && typeof data == 'string' && data.charCodeAt(0) == '0xFEFF') {
-	    return data.slice(1);
-	}
-	return data;
+            return data.slice(1);
+        }
+        return data;
     },
 
     _transform: function (data, encoding, done) {

test/parsing.test.js

@@ -440,6 +440,63 @@ var expected26 = [
 
 var expected27 = expected26;
 
+var expectedRenameHeaders = [
+    {
+        "firstName": "First1",
+        "lastName": "Last1",
+        "emailAddress": "email1@email.com",
+        address: "1 Street St, State ST, 88888"
+    },
+    {
+        "firstName": "First2",
+        "lastName": "Last2",
+        "emailAddress": "email2@email.com",
+        address: "2 Street St, State ST, 88888"
+    },
+    {
+        "firstName": "First3",
+        "lastName": "Last3",
+        "emailAddress": "email3@email.com",
+        address: "3 Street St, State ST, 88888"
+    },
+    {
+        "firstName": "First4",
+        "lastName": "Last4",
+        "emailAddress": "email4@email.com",
+        address: "4 Street St, State ST, 88888"
+    },
+    {
+        "firstName": "First5",
+        "lastName": "Last5",
+        "emailAddress": "email5@email.com",
+        address: "5 Street St, State ST, 88888"
+    },
+    {
+        "firstName": "First6",
+        "lastName": "Last6",
+        "emailAddress": "email6@email.com",
+        address: "6 Street St, State ST, 88888"
+    },
+    {
+        "firstName": "First7",
+        "lastName": "Last7",
+        "emailAddress": "email7@email.com",
+        address: "7 Street St, State ST, 88888"
+    },
+    {
+        "firstName": "First8",
+        "lastName": "Last8",
+        "emailAddress": "email8@email.com",
+        address: "8 Street St, State ST, 88888"
+    },
+    {
+        "firstName": "First9",
+        "lastName": "Last9",
+        "emailAddress": "email9@email.com",
+        address: "9 Street St, State ST, 88888"
+    }
+];
+
 it.describe("fast-csv parsing", function (it) {
 
     it.timeout(60000);
@@ -605,6 +662,53 @@ it.describe("fast-csv parsing", function (it) {
             });
     });
 
+    it.should("allow renaming columns", function (next) {
+        var actual = [];
+        csv
+            .fromPath(path.resolve(__dirname, "./assets/test1.csv"), { headers: ["firstName", "lastName", "emailAddress", "address"], renameHeaders: true })
+            .on("data", function (data, index) {
+                actual.push(data);
+            })
+            .on("error", next)
+            .on("end", function (count) {
+                assert.deepEqual(actual, expectedRenameHeaders);
+                assert.equal(count, actual.length);
+                next();
+            });
+    });
+
+    it.should("propagate an error when trying to rename headers without providing new ones", function (next) {
+        var actual = [];
+        csv
+            .fromPath(path.resolve(__dirname, "./assets/test1.csv"), { renameHeaders: true })
+            .on("data", function (data, index) {
+                actual.push(data);
+            })
+            .on("error", function (err) {
+                assert.equal(err.message, "Error renaming headers: new headers must be provided in an array");
+                next();
+            })
+            .on("end", function (count) {
+                next(new Error("Rename headers without headers error not propagated"));
+            });
+    });
+
+    it.should("propagate an error when trying to rename headers without providing proper ones", function (next) {
+        var actual = [];
+        csv
+            .fromPath(path.resolve(__dirname, "./assets/test1.csv"), { renameHeaders: true, headers: true })
+            .on("data", function (data, index) {
+                actual.push(data);
+            })
+            .on("error", function (err) {
+                assert.equal(err.message, "Error renaming headers: new headers must be provided in an array");
+                next();
+            })
+            .on("end", function (count) {
+                next(new Error("Rename headers without headers error not propagated"));
+            });
+    });
+
     it.should("allow specifying of columns as a sparse array", function (next) {
         var actual = [];
         csv