feat(gatsby-plugin-sharp): cache base64 if possible (gatsbyjs#9059)

Closes: gatsbyjs#6999  
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packages/gatsby-plugin-sharp/src/index.js

@@ -441,7 +441,7 @@ function queueImageResizing({ file, args = {}, reporter }) {
   }
 }
 
-async function notMemoizedbase64({ file, args = {}, reporter }) {
+async function generateBase64({ file, args, reporter }) {
   const options = healOptions(args, { width: 20 })
   let pipeline
   try {
@@ -484,29 +484,46 @@ async function notMemoizedbase64({ file, args = {}, reporter }) {
       pipeline
     )
   }
-
   const [buffer, info] = await pipeline.toBufferAsync()
-  const originalName = file.base
-
-  return {
+  const base64output = {
     src: `data:image/${info.format};base64,${buffer.toString(`base64`)}`,
     width: info.width,
     height: info.height,
     aspectRatio: info.width / info.height,
-    originalName: originalName,
+    originalName: file.base,
   }
+  return base64output
 }
 
-const memoizedBase64 = _.memoize(
-  notMemoizedbase64,
-  ({ file, args }) => `${file.id}${JSON.stringify(args)}`
-)
+const base64CacheKey = ({ file, args }) => `${file.id}${JSON.stringify(args)}`
+
+const memoizedBase64 = _.memoize(generateBase64, base64CacheKey)
+
+const cachifiedBase64 = async ({ cache, ...arg }) => {
+  const cacheKey = base64CacheKey(arg)
+
+  const cachedBase64 = await cache.get(cacheKey)
+  if (cachedBase64) {
+    return cachedBase64
+  }
+
+  const base64output = await generateBase64(arg)
+
+  await cache.set(cacheKey, base64output)
+
+  return base64output
+}
+
+async function base64(arg) {
+  if (arg.cache) {
+    // Not all tranformer plugins are going to provide cache
+    return await cachifiedBase64(arg)
+  }
 
-async function base64(args) {
-  return await memoizedBase64(args)
+  return await memoizedBase64(arg)
 }
 
-async function fluid({ file, args = {}, reporter }) {
+async function fluid({ file, args = {}, reporter, cache }) {
   const options = healOptions(args, {})
 
   // Account for images with a high pixel density. We assume that these types of
@@ -634,7 +651,7 @@ async function fluid({ file, args = {}, reporter }) {
   }
 
   // Get base64 version
-  const base64Image = await base64({ file, args: base64Args, reporter })
+  const base64Image = await base64({ file, args: base64Args, reporter, cache })
 
   // Construct src and srcSet strings.
   const originalImg = _.maxBy(images, image => image.width).src
@@ -682,7 +699,7 @@ async function fluid({ file, args = {}, reporter }) {
   }
 }
 
-async function fixed({ file, args = {}, reporter }) {
+async function fixed({ file, args = {}, reporter, cache }) {
   const options = healOptions(args, {})
 
   // if no width is passed, we need to resize the image based on the passed height
@@ -744,7 +761,7 @@ async function fixed({ file, args = {}, reporter }) {
   }
 
   // Get base64 version
-  const base64Image = await base64({ file, args: base64Args, reporter })
+  const base64Image = await base64({ file, args: base64Args, reporter, cache })
 
   const fallbackSrc = images[0].src
   const srcSet = images

packages/gatsby-remark-images/src/index.js

@@ -15,7 +15,7 @@ const slash = require(`slash`)
 // 4. Create the responsive images.
 // 5. Set the html w/ aspect ratio helper.
 module.exports = (
-  { files, markdownNode, markdownAST, pathPrefix, getNode, reporter },
+  { files, markdownNode, markdownAST, pathPrefix, getNode, reporter, cache },
   pluginOptions
 ) => {
   const defaults = {
@@ -83,6 +83,7 @@ module.exports = (
       file: imageNode,
       args: options,
       reporter,
+      cache,
     })
 
     if (!fluidResult) {

packages/gatsby-transformer-sharp/src/extend-node-type.js

@@ -51,6 +51,7 @@ const fixedNodeType = ({
   getNodeAndSavePathDependency,
   reporter,
   name,
+  cache,
 }) => {
   return {
     type: new GraphQLObjectType({
@@ -80,6 +81,7 @@ const fixedNodeType = ({
                 file,
                 args,
                 reporter,
+                cache,
               })
             ).then(({ src }) => src)
           },
@@ -96,6 +98,7 @@ const fixedNodeType = ({
                 file,
                 args,
                 reporter,
+                cache,
               })
             ).then(({ srcSet }) => srcSet)
           },
@@ -151,6 +154,7 @@ const fixedNodeType = ({
           file,
           args,
           reporter,
+          cache,
         })
       ).then(o =>
         Object.assign({}, o, {
@@ -169,6 +173,7 @@ const fluidNodeType = ({
   getNodeAndSavePathDependency,
   reporter,
   name,
+  cache,
 }) => {
   return {
     type: new GraphQLObjectType({
@@ -194,6 +199,7 @@ const fluidNodeType = ({
                 file,
                 args,
                 reporter,
+                cache,
               })
             ).then(({ src }) => src)
           },
@@ -210,6 +216,7 @@ const fluidNodeType = ({
                 file,
                 args,
                 reporter,
+                cache,
               })
             ).then(({ srcSet }) => srcSet)
           },
@@ -278,6 +285,7 @@ const fluidNodeType = ({
           file,
           args,
           reporter,
+          cache,
         })
       ).then(o =>
         Object.assign({}, o, {
@@ -295,6 +303,7 @@ module.exports = ({
   pathPrefix,
   getNodeAndSavePathDependency,
   reporter,
+  cache,
 }) => {
   if (type.name !== `ImageSharp`) {
     return {}
@@ -305,6 +314,7 @@ module.exports = ({
     pathPrefix,
     getNodeAndSavePathDependency,
     reporter,
+    cache,
   }
 
   // TODO: Remove resolutionsNode and sizesNode for Gatsby v3
@@ -440,6 +450,7 @@ module.exports = ({
             resolve(
               base64({
                 file,
+                cache,
               })
             )
           } else {