add flatten background color option (#86)

* Update index.js support flatten background color * Update README.md update README
onildoaguiar · Aug 14, 2024 · 0145ba7 · 0145ba7
1 parent 4ef86d1
commit 0145ba7
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diff --git a/README.md b/README.md
@@ -110,6 +110,7 @@ try {
   - __fit__ [string] - method by which the image should fit the width/height. Default = contain ([details](https://sharp.pixelplumbing.com/api-resize))
   - __failOnError__ [boolean] - Set to false to avoid read problems for images from some phones (i.e Samsung) in the sharp lib. Default = true ([details](https://github.com/lovell/sharp/issues/1578))
   - __withMetaData__ [boolean] - Keep metadata in the thumbnail (will increase file size)
+  - __flattenBackgroundColor__ [background colour] - parsed by the color module, defaults to #ffffff.
 
 ### Examples
 ```js

diff --git a/src/index.js b/src/index.js
@@ -12,10 +12,10 @@ const { fail } = require('assert');
 const PERCENTAGE = 10;
 const RESPONSE_TYPE = 'buffer';
 
-const fromBase64 = async (source, percentage, width, height, responseType, jpegOptions, fit, failOnError, withMetaData) => {
+const fromBase64 = async (source, percentage, width, height, responseType, jpegOptions, fit, failOnError, withMetaData, flattenBackgroundColor) => {
     const imageBuffer = Buffer.from(source, 'base64');
     const dimensions = getDimensions(imageBuffer, percentage, { width, height });
-    const thumbnailBuffer = await sharpResize(imageBuffer, dimensions, jpegOptions, fit, failOnError, withMetaData);
+    const thumbnailBuffer = await sharpResize(imageBuffer, dimensions, jpegOptions, fit, failOnError, withMetaData, flattenBackgroundColor);
 
     if (responseType === 'base64') {
         return thumbnailBuffer.toString('base64');
@@ -24,13 +24,12 @@ const fromBase64 = async (source, percentage, width, height, responseType, jpegO
     return thumbnailBuffer;
 };
 
-const fromUri = async (source, percentage, width, height, responseType, jpegOptions, fit, failOnError, withMetaData) => {
+const fromUri = async (source, percentage, width, height, responseType, jpegOptions, fit, failOnError, withMetaData, flattenBackgroundColor) => {
     const response = await axios.get(source.uri, { responseType: 'arraybuffer' });
     const imageBuffer = Buffer.from(response.data, 'binary');
 
     const dimensions = getDimensions(imageBuffer, percentage, { width, height });
-    const thumbnailBuffer = await sharpResize(imageBuffer, dimensions, jpegOptions, fit, failOnError, withMetaData);
-
+    const thumbnailBuffer = await sharpResize(imageBuffer, dimensions, jpegOptions, fit, failOnError, withMetaData, flattenBackgroundColor);
 
     if (responseType === 'base64') {
         return thumbnailBuffer.toString('base64');
@@ -39,11 +38,11 @@ const fromUri = async (source, percentage, width, height, responseType, jpegOpti
     return thumbnailBuffer;
 };
 
-const fromPath = async (source, percentage, width, height, responseType, jpegOptions, fit, failOnError, withMetaData) => {
+const fromPath = async (source, percentage, width, height, responseType, jpegOptions, fit, failOnError, withMetaData, flattenBackgroundColor) => {
     const imageBuffer = fs.readFileSync(source);
 
     const dimensions = getDimensions(imageBuffer, percentage, { width, height });
-    const thumbnailBuffer = await sharpResize(imageBuffer, dimensions, jpegOptions, fit, failOnError, withMetaData);
+    const thumbnailBuffer = await sharpResize(imageBuffer, dimensions, jpegOptions, fit, failOnError, withMetaData, flattenBackgroundColor);
 
     if (responseType === 'base64') {
         return thumbnailBuffer.toString('base64');
@@ -52,10 +51,21 @@ const fromPath = async (source, percentage, width, height, responseType, jpegOpt
     return thumbnailBuffer;
 };
 
-const fromReadStream = async (source, percentage, width, height, responseType, jpegOptions, fit, failOnError, withMetaData) => {
+const fromReadStream = async (
+    source,
+    percentage,
+    width,
+    height,
+    responseType,
+    jpegOptions,
+    fit,
+    failOnError,
+    withMetaData,
+    flattenBackgroundColor,
+) => {
     const imageBuffer = await util.streamToBuffer(source);
     const dimensions = getDimensions(imageBuffer, percentage, { width, height });
-    const thumbnailBuffer = await sharpResize(imageBuffer, dimensions, jpegOptions, fit, failOnError, withMetaData);
+    const thumbnailBuffer = await sharpResize(imageBuffer, dimensions, jpegOptions, fit, failOnError, withMetaData, flattenBackgroundColor);
 
     if (responseType === 'base64') {
         return thumbnailBuffer.toString('base64');
@@ -64,11 +74,10 @@ const fromReadStream = async (source, percentage, width, height, responseType, j
     return thumbnailBuffer;
 };
 
-const fromBuffer = async (source, percentage, width, height, responseType, jpegOptions, fit, failOnError, withMetaData) => {
+const fromBuffer = async (source, percentage, width, height, responseType, jpegOptions, fit, failOnError, withMetaData, flattenBackgroundColor) => {
     const imageBuffer = source;
-
     const dimensions = getDimensions(imageBuffer, percentage, { width, height });
-    const thumbnailBuffer = await sharpResize(imageBuffer, dimensions, jpegOptions, fit, failOnError, withMetaData);
+    const thumbnailBuffer = await sharpResize(imageBuffer, dimensions, jpegOptions, fit, failOnError, withMetaData, flattenBackgroundColor);
 
     if (responseType === 'base64') {
         return thumbnailBuffer.toString('base64');
@@ -84,26 +93,82 @@ module.exports = async (source, options) => {
     const responseType = options && options.responseType ? options.responseType : RESPONSE_TYPE;
     const jpegOptions = options && options.jpegOptions ? options.jpegOptions : undefined;
     const fit = options && options.fit ? options.fit : undefined;
-    const failOnError = options && typeof(options.failOnError) !== 'undefined' ? options.failOnError : true;
-    const withMetaData = options && typeof(options.withMetaData) !== 'undefined' ? options.withMetaData : false;
+    const failOnError = options && typeof options.failOnError !== 'undefined' ? options.failOnError : true;
+    const withMetaData = options && typeof options.withMetaData !== 'undefined' ? options.withMetaData : false;
+    const flattenBackgroundColor = options && typeof options.flattenBackgroundColor !== 'undefined' ? options.flattenBackgroundColor : '#ffffff';
 
     try {
         switch (typeof source) {
             case 'object':
                 let response;
                 if (source instanceof fs.ReadStream || source instanceof stream.PassThrough) {
-                    response = await fromReadStream(source, percentage, width, height, responseType, jpegOptions, fit, failOnError, withMetaData);
+                    response = await fromReadStream(
+                        source,
+                        percentage,
+                        width,
+                        height,
+                        responseType,
+                        jpegOptions,
+                        fit,
+                        failOnError,
+                        withMetaData,
+                        flattenBackgroundColor,
+                    );
                 } else if (source instanceof Buffer) {
-                    response = await fromBuffer(source, percentage, width, height, responseType, jpegOptions, fit, failOnError, withMetaData);
+                    response = await fromBuffer(
+                        source,
+                        percentage,
+                        width,
+                        height,
+                        responseType,
+                        jpegOptions,
+                        fit,
+                        failOnError,
+                        withMetaData,
+                        flattenBackgroundColor,
+                    );
                 } else {
-                    response = await fromUri(source, percentage, width, height, responseType, jpegOptions, fit, failOnError, withMetaData);
+                    response = await fromUri(
+                        source,
+                        percentage,
+                        width,
+                        height,
+                        responseType,
+                        jpegOptions,
+                        fit,
+                        failOnError,
+                        withMetaData,
+                        flattenBackgroundColor,
+                    );
                 }
                 return response;
             case 'string':
                 if (validator.isBase64(source)) {
-                    return await fromBase64(source, percentage, width, height, responseType, jpegOptions, fit, failOnError, withMetaData);
+                    return await fromBase64(
+                        source,
+                        percentage,
+                        width,
+                        height,
+                        responseType,
+                        jpegOptions,
+                        fit,
+                        failOnError,
+                        withMetaData,
+                        flattenBackgroundColor,
+                    );
                 } else {
-                    return await fromPath(source, percentage, width, height, responseType, jpegOptions, fit, failOnError, withMetaData);
+                    return await fromPath(
+                        source,
+                        percentage,
+                        width,
+                        height,
+                        responseType,
+                        jpegOptions,
+                        fit,
+                        failOnError,
+                        withMetaData,
+                        flattenBackgroundColor,
+                    );
                 }
             default:
                 throw new Error('unsupported source type');
@@ -124,26 +189,28 @@ const getDimensions = (imageBuffer, percentageOfImage, dimensions) => {
     const height = parseInt((originalDimensions.height * (percentageOfImage / 100)).toFixed(0));
 
     return { width, height };
-}
+};
 
-const sharpResize = (imageBuffer, dimensions, jpegOptions, fit, failOnError, withMetadata) => {
+const sharpResize = (imageBuffer, dimensions, jpegOptions, fit, failOnError, withMetadata, flattenBackgroundColor) => {
     return new Promise((resolve, reject) => {
         let result = sharp(imageBuffer, { failOnError })
             .resize({
-                ...dimensions, withoutEnlargement: true, fit: fit ? fit : 'contain',
+                ...dimensions,
+                withoutEnlargement: true,
+                fit: fit ? fit : 'contain',
             })
+            .flatten({ background: flattenBackgroundColor });
 
-            if(withMetadata){
-              result.withMetadata()
-            }
+        if (withMetadata) {
+            result.withMetadata();
+        }
 
-            result.jpeg(jpegOptions ? jpegOptions : { force: false })
-            .toBuffer((err, data) => {
-                if (err) {
-                    reject(err);
-                } else {
-                    resolve(data);
-                }
-            });
+        result.jpeg(jpegOptions ? jpegOptions : { force: false }).toBuffer((err, data) => {
+            if (err) {
+                reject(err);
+            } else {
+                resolve(data);
+            }
+        });
     });
 };