이미지 최적화 작업 큐 추가

backend/src/lib/image-storage.js

@@ -3,10 +3,19 @@ const path = require('path')
 const crypto = require('crypto')
 const sharp = require('sharp')
 const { nanoid } = require('nanoid')
-const { findImageAssetByHash, createImageAsset } = require('../db')
+const {
+  findImageAssetByHash,
+  createImageAsset,
+  createImageOptimizationJob,
+  updateImageOptimizationJobStatus,
+} = require('../db')
 
 const UPLOAD_ROOT = path.join(__dirname, '..', '..', 'uploads')
 const OPTIMIZED_DIR = 'assets'
+const OPTIMIZATION_CONCURRENCY = Math.max(1, Number(process.env.IMAGE_OPTIMIZATION_CONCURRENCY || 1))
+
+let activeCount = 0
+const pendingJobs = []
 
 function ensureImageMimeType(file) {
   return typeof file?.mimetype === 'string' && file.mimetype.startsWith('image/')
@@ -26,26 +35,21 @@ function createMemoryUpload(multer, { fileSize = 6 * 1024 * 1024, maxCount } = {
   })
 }
 
-async function writeOptimizedImage({
-  file,
-  directory,
-  width,
-  height,
-  fit = 'inside',
-  quality = 82,
-}) {
-  if (!file?.buffer?.length) {
-    const error = new Error('file_required')
-    error.code = 'file_required'
-    throw error
-  }
-
-  if (!ensureImageMimeType(file)) {
-    const error = new Error('image_file_required')
-    error.code = 'image_file_required'
-    throw error
+function scheduleQueue() {
+  while (activeCount < OPTIMIZATION_CONCURRENCY && pendingJobs.length) {
+    const job = pendingJobs.shift()
+    activeCount += 1
+    processQueuedJob(job)
+      .then(job.resolve)
+      .catch(job.reject)
+      .finally(() => {
+        activeCount = Math.max(0, activeCount - 1)
+        scheduleQueue()
+      })
   }
+}
 
+async function optimizeAndPersist({ file, width, height, fit, quality }) {
   const { data, info } = await sharp(file.buffer, { failOn: 'none' })
     .rotate()
     .resize({
@@ -68,7 +72,6 @@ async function writeOptimizedImage({
       height: existing.height,
       contentHash: existing.contentHash,
       reused: true,
-      directory,
     }
   }
 
@@ -100,7 +103,6 @@ async function writeOptimizedImage({
       height: asset.height,
       contentHash: asset.contentHash,
       reused: false,
-      directory,
     }
   } catch (error) {
     try {
@@ -120,7 +122,6 @@ async function writeOptimizedImage({
           height: asset.height,
           contentHash: asset.contentHash,
           reused: true,
-          directory,
         }
       }
     }
@@ -129,8 +130,89 @@ async function writeOptimizedImage({
   }
 }
 
+async function processQueuedJob(job) {
+  await updateImageOptimizationJobStatus({
+    id: job.jobId,
+    status: 'processing',
+    startedAt: Date.now(),
+  })
+
+  try {
+    const result = await optimizeAndPersist(job)
+    await updateImageOptimizationJobStatus({
+      id: job.jobId,
+      status: 'completed',
+      optimizedByteSize: result.size,
+      reusedAsset: result.reused,
+      finishedAt: Date.now(),
+    })
+    return result
+  } catch (error) {
+    await updateImageOptimizationJobStatus({
+      id: job.jobId,
+      status: 'failed',
+      errorMessage: error?.message || 'optimization_failed',
+      finishedAt: Date.now(),
+    })
+    throw error
+  }
+}
+
+async function writeOptimizedImage({
+  file,
+  directory,
+  width,
+  height,
+  fit = 'inside',
+  quality = 82,
+}) {
+  if (!file?.buffer?.length) {
+    const error = new Error('file_required')
+    error.code = 'file_required'
+    throw error
+  }
+
+  if (!ensureImageMimeType(file)) {
+    const error = new Error('image_file_required')
+    error.code = 'image_file_required'
+    throw error
+  }
+
+  const jobId = nanoid()
+  await createImageOptimizationJob({
+    id: jobId,
+    sourceCategory: directory,
+    targetDirectory: OPTIMIZED_DIR,
+    originalByteSize: file.size || file.buffer.length,
+  })
+
+  return new Promise((resolve, reject) => {
+    pendingJobs.push({
+      jobId,
+      file,
+      directory,
+      width,
+      height,
+      fit,
+      quality,
+      resolve: (result) => resolve({ ...result, directory }),
+      reject,
+    })
+    scheduleQueue()
+  })
+}
+
+function getImageOptimizationQueueState() {
+  return {
+    concurrency: OPTIMIZATION_CONCURRENCY,
+    activeCount,
+    pendingCount: pendingJobs.length,
+  }
+}
+
 module.exports = {
   createMemoryUpload,
   ensureImageMimeType,
   writeOptimizedImage,
+  getImageOptimizationQueueState,
 }