fast-csv - npm Package Compare versions

Comparing version 0.3.0 to 0.3.1

lib/formatter.js

@@ -46,11 +46,19 @@ var fs = require("fs"),
 
+function defaultTransform(row) {
+    return row;
+}
+
 function __write(writer, arr, options) {
     options = options || {};
     var formatter = createFormatter(options),
+        transformer = extended.has(options, "transform") ? options.transform : defaultTransform,
         hasHeaders = extended.has(options, "headers") ? options.headers : true,
+        headersLength = 0,
         i = -1,
+        j = -1,
         l = arr.length,
         ret = [];
     if (l) {
-        var item = arr[0], isHash = !extended.isArray(item), headers;
+        var item = arr[0], isHash = !extended.isArray(item), headers, vals;
+        item = transformer(item);
         if (hasHeaders) {
@@ -63,7 +71,21 @@ if (isHash) {
             }
+            headersLength = headers.length;
             ret.push(formatter(headers));
         }
         while (++i < l) {
-            item = arr[i];
-            ret.push(formatter(isHash ? hash.values(item) : item));
+            item = transformer(arr[i]);
+            vals = item;
+            if (hasHeaders && isHash) {
+                j = -1;
+                vals = [];
+                while (++j < headersLength) {
+                    vals[j] = item[headers[j]];
+                }
+            } else if (isHash) {
+                j = -1;
+                while (++j < headersLength) {
+                    vals[j] = item[j];
+                }
+            }
+            ret.push(formatter(vals));
         }
@@ -74,26 +96,40 @@ writer.push(ret.join(LINE_BREAK));
 
-function wrapWriter(writer, options) {
+var transformStreamWrite = Transform.prototype.write;
+
+function CsvTransformStream(options) {
     options = options || {};
-    var formatter = createFormatter(options),
-        hasHeaders = extended.has(options, "headers") ? options.headers : true,
-        parsedHeaders = hasHeaders ? false : true,
-        headersLength = 0, i = -1,
-        writerWrite = writer.write, headers,
-        buffer = [],
-        totalCount = 0,
-        MAX_BUFFER_SIZE = options.maxBuffer || 100000;
+    Transform.call(this, options);
+    this.formatter = createFormatter(options);
+    var hasHeaders = this.hasHeaders = extended.has(options, "headers") ? options.headers : true;
+    this.parsedHeaders = hasHeaders ? false : true;
+    this.buffer = [];
+    this.maxBufferSize = options.maxBuffer || 100000;
+    extended.has(options, "transform") && this.transform(options.transform);
+}
 
-    writer.write = function (item) {
+util.inherits(CsvTransformStream, Transform);
+
+extended(CsvTransformStream).extend({
+
+    headers: null,
+
+    headersLength: 0,
+
+    totalCount: 0,
+
+    write: function (item) {
+        var buffer = this.buffer, headers = this.headers;
         if (item) {
+            item = this.__transform(item);
             var isHash = !extended.isArray(item), vals;
-            if (!parsedHeaders) {
-                totalCount++;
-                parsedHeaders = true;
+            if (!this.parsedHeaders) {
+                this.totalCount++;
+                this.parsedHeaders = true;
                 if (isHash) {
-                    headers = hash.keys(item);
+                    headers = this.headers = hash.keys(item);
                 } else {
-                    headers = item;
+                    headers = this.headers = item;
                 }
-                headersLength = headers.length;
-                buffer.push(formatter(headers));
+                this.headersLength = headers.length;
+                buffer.push(this.formatter(headers));
                 if (!isHash) {
@@ -103,7 +139,7 @@ return;
             }
-            if (totalCount++) {
+            if (this.totalCount++) {
                 buffer.push("\n");
             }
             if (isHash) {
-                i = -1;
+                var i = -1, headersLength = this.headersLength;
                 vals = [];
@@ -116,5 +152,5 @@ while (++i < headersLength) {
             }
-            buffer.push(formatter(vals));
-            if (buffer.length >= MAX_BUFFER_SIZE) {
-                writerWrite.call(writer, new Buffer(buffer.join("")).toString("utf8"));
+            buffer.push(this.formatter(vals));
+            if (buffer.length >= this.maxBufferSize) {
+                transformStreamWrite.call(this, new Buffer(buffer.join("")).toString("utf8"));
                 buffer.length = 0;
@@ -124,20 +160,19 @@ }
             if (buffer.length) {
-                writerWrite.call(writer, new Buffer(buffer.join("")).toString("utf8"));
+                transformStreamWrite.call(this, new Buffer(buffer.join("")).toString("utf8"));
                 buffer.length = 0;
             }
-            writer.end();
+            this.end();
         }
-    };
-    return writer;
-}
+    },
 
-function CsvTransformStream(opts) {
-    Transform.call(this, opts);
-    wrapWriter(this, opts);
-}
+    __transform: defaultTransform,
 
-util.inherits(CsvTransformStream, Transform);
+    transform: function (cb) {
+        if (!extended.isFunction(cb)) {
+            throw new TypeError("fast-csv.Parser#transform requires a function");
+        }
+        this.__transform = cb;
+        return this;
+    },
 
-extended(CsvTransformStream).extend({
-
     _transform: function (str, encoding, cb) {
@@ -177,4 +212,3 @@ cb(null, str);
     var stream = fs.createWriteStream(path, {encoding: "utf8"});
-    write(arr, options).pipe(stream);
-    return stream;
+    return write(arr, options).pipe(stream);
 }
@@ -184,11 +218,6 @@
 createFormatter.write = write;
-
 createFormatter.createWriteStream = createWriteStream;
-
 createFormatter.writeToString = writeToString;
-
 createFormatter.writeToPath = writeToPath;
-
 createFormatter.writeToStream = writeToStream;
-
 module.exports = createFormatter;

lib/parser_stream.js

@@ -34,3 +34,3 @@ var extended = require("./extended"),
     options = options || {};
-    options.objectMode = extended.has(options, "objectMode") ? options.objectMode : true
+    options.objectMode = extended.has(options, "objectMode") ? options.objectMode : true;
     stream.Transform.call(this, options);
@@ -37,0 +37,0 @@ this.lines = "";

package.json

 {
-    "name": "fast-csv",
-    "version": "0.3.0",
-    "description": "CSV parser and writer",
-    "main": "index.js",
-    "scripts": {
-        "test": "grunt"
-    },
-    "repository": {
-        "type": "git",
-        "url": "[e-mail]:C2FO/fast-csv.git"
-    },
-    "keywords": [
-        "csv",
-        "parser",
-        "fast",
-        "writer",
-        "csv writer",
-        "CSV"
-    ],
-    "homepage": "http://c2fo.github.com/fast-csv/index.html",
-    "author": "Doug Martin",
-    "license": "MIT",
-    "devDependencies": {
-        "it": "~0.2.6",
-        "grunt-it": "~0.3.1",
-        "grunt": "~0.4.1",
-        "grunt-contrib-jshint": "~0.10.0"
-    },
-    "engines": {
-        "node": ">=0.10"
-    },
-    "dependencies": {
-        "is-extended": "0.0.10",
-        "object-extended": "0.0.7",
-        "extended": "0.0.6",
-        "string-extended": "0.0.8"
-    }
+  "name": "fast-csv",
+  "version": "0.3.1",
+  "description": "CSV parser and writer",
+  "main": "index.js",
+  "scripts": {
+    "test": "grunt jshint it"
+  },
+  "repository": {
+    "type": "git",
+    "url": "[e-mail]:C2FO/fast-csv.git"
+  },
+  "keywords": [
+    "csv",
+    "parser",
+    "fast",
+    "writer",
+    "csv writer",
+    "CSV"
+  ],
+  "homepage": "http://c2fo.github.com/fast-csv/index.html",
+  "author": "Doug Martin",
+  "license": "MIT",
+  "devDependencies": {
+    "it": "~0.2.6",
+    "grunt-it": "~0.3.1",
+    "grunt": "~0.4.1",
+    "grunt-contrib-jshint": "~0.10.0",
+    "grunt-exec": "^0.4.5"
+  },
+  "engines": {
+    "node": ">=0.10"
+  },
+  "dependencies": {
+    "is-extended": "0.0.10",
+    "object-extended": "0.0.7",
+    "extended": "0.0.6",
+    "string-extended": "0.0.8"
+  }
 }

README.md

@@ -34,5 +34,5 @@ [![build status](https://secure.travis-ci.org/C2FO/fast-csv.png)](http://travis-ci.org/C2FO/fast-csv)
 
-`record`: Emitted when a record is parsed.
-`data-invalid`: Emitted if there was invalid row encounted, **only emitted if the `validate` function is used**.
-`data`: Emitted with the `stringified` version of a record.
+* `record`: Emitted when a record is parsed.
+* `data-invalid`: Emitted if there was invalid row encounted, **only emitted if the `validate` function is used**.
+* `data`: Emitted with the object or `stringified` version if the `objectMode` is set to `false`.
 
@@ -216,4 +216,6 @@ **([options])**
 
-Formatting accepts the same options as parsing.
+Formatting accepts the same options as parsing with an additional `transform` option.
 
+* `transform(row)`: A function that accepts a row and returns a transformed one to be written.
+
 **`createWriteStream(options)`**
@@ -240,2 +242,28 @@
 
+If you wish to transform rows as writing then you can use the `.transform` method.
+
+```javascript
+var csvStream = csv
+    .createWriteStream({headers: true})
+    .transform(function(row){
+        return {
+           A: row.a,
+           B: row.b
+        };
+    }),
+    writableStream = fs.createWriteStream("my.csv");
+
+writableStream.on("finish", function(){
+  console.log("DONE!");
+});
+
+csvSream.pipe(writableStream);
+csvStream.write({a: "a0", b: "b0"});
+csvStream.write({a: "a1", b: "b1"});
+csvStream.write({a: "a2", b: "b2"});
+csvStream.write({a: "a3", b: "b4"});
+csvStream.write({a: "a3", b: "b4"});
+csvStream.write(null);
+```
+
 **Writing Data**
@@ -250,3 +278,3 @@
 ```javascript
-var ws = fs.createWritableStream("my.csv");
+var ws = fs.createWriteStream("my.csv");
 csv
@@ -262,3 +290,3 @@ .write([
 ```javascript
-var ws = fs.createWritableStream("my.csv");
+var ws = fs.createWriteStream("my.csv");
 csv
@@ -272,2 +300,22 @@ .write([
 
+```javascript
+var ws = fs.createWriteStream("my.csv");
+csv
+   .write([
+       {a: "a1", b: "b1"},
+       {a: "a2", b: "b2"}
+   ], {
+        headers: true
+        transform: function(row){
+            return {
+                A: row.a,
+                B: row.b
+            };
+        }
+   })
+   .pipe(ws);
+```
+
+
+
 **`writeToStream(stream,arr[, options])`**
@@ -279,3 +327,3 @@
 csv
-   .writeToStream(fs.createWritableStream("my.csv"), [
+   .writeToStream(fs.createWriteStream("my.csv"), [
        ["a", "b"],
@@ -289,3 +337,3 @@ ["a1", "b1"],
 csv
-   .writeToStream(fs.createWritableStream("my.csv"), [
+   .writeToStream(fs.createWriteStream("my.csv"), [
        {a: "a1", b: "b1"},
@@ -297,2 +345,19 @@ {a: "a2", b: "b2"}
 
+```javascript
+csv
+   .writeToStream(fs.createWriteStream("my.csv"), [
+       {a: "a1", b: "b1"},
+       {a: "a2", b: "b2"}
+   ], {
+        headers: true,
+        transform: function(row){
+            return {
+                A: row.a,
+                B: row.b
+            };
+        }
+   })
+   .pipe(ws);
+```
+
 **`writeToPath(arr[, options])`**
@@ -325,2 +390,21 @@
 
+```javascript
+csv
+   .writeToStream("my.csv", [
+       {a: "a1", b: "b1"},
+       {a: "a2", b: "b2"}
+   ], {
+        headers: true,
+        transform: function(row){
+            return {
+                A: row.a,
+                B: row.b
+            };
+        }
+   })
+   .on("finish", function(){
+      console.log("done!");
+   });
+```
+
 **`writeToString(arr[, options])`**
@@ -343,2 +427,17 @@
 
+```javascript
+csv.writeToString([
+   {a: "a1", b: "b1"},
+   {a: "a2", b: "b2"}
+], {
+        headers: true,
+        transform: function(row){
+            return {
+                A: row.a,
+                B: row.b
+            };
+        }
+   }); //"a,b\na1,b1\na2,b2\n"
+```
+
 ## Piping from Parser to Writer
@@ -375,2 +474,23 @@
 
+If you want to tranform on the formatting side
+
+
+```javascript
+var formatStream = csv
+        .createWriteStream({headers: true})
+        .transform(function(){
+            return {
+                name: obj.Name,
+                address: obj.Address,
+                emailAddress: obj.Email_Address,
+                verified: obj.Verified
+            };
+        });  
+csv
+   .fromPath("in.csv", {headers: true})
+   .pipe(formatStream)
+   .pipe(fs.createWriteStream("out.csv", {encoding: "utf8"}));
+```
+
+
 ## Benchmarks
@@ -377,0 +497,0 @@

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Found 1 instance in 1 package

Fixed alerts

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Improved metrics

Total package byte prevSize

103115

increased by3.02%

Lines of code

619

increased by4.74%

Number of lines in readme file

522

increased by29.85%

Worsened metrics

Dev dependency count

5

increased by25%

No dependency changes