fix: ranged requests handled properly

src/lib/datasources/Datasource.ts

@@ -9,4 +9,5 @@ export abstract class Datasource {
   public abstract size(file: string): Promise<number | null>;
   public abstract get(file: string): Readable | Promise<Readable>;
   public abstract fullSize(): Promise<number>;
+  public abstract range(file: string, start: number, end: number): Promise<Readable>;
 }

src/lib/datasources/Local.ts

@@ -11,7 +11,7 @@ export class Local extends Datasource {
   }
 
   public async save(file: string, data: Buffer): Promise<void> {
-    await writeFile(join(this.path, file), data);
+    await writeFile(join(this.path, file), Uint8Array.from(data));
   }
 
   public async delete(file: string): Promise<void> {
@@ -56,4 +56,11 @@ export class Local extends Datasource {
 
     return size;
   }
+
+  public async range(file: string, start: number, end: number): Promise<ReadStream> {
+    const path = join(this.path, file);
+    const readStream = createReadStream(path, { start, end });
+
+    return readStream;
+  }
 }

src/lib/datasources/S3.ts

@@ -81,4 +81,15 @@ export class S3 extends Datasource {
       });
     });
   }
+
+  public async range(file: string, start: number, end: number): Promise<Readable> {
+    return new Promise((res) => {
+      this.s3.getPartialObject(this.config.bucket, file, start, end, (err, stream) => {
+        if (err) {
+          console.log(err);
+          res(null);
+        } else res(stream);
+      });
+    });
+  }
 }

src/lib/utils/range.ts

@@ -1,9 +1,20 @@
-export function parseRangeHeader(header?: string): [number, number] {
-  if (!header || !header.startsWith('bytes=')) return [0, Infinity];
+export function parseRange(header: string, length: number): [number, number] {
+  const range = header.trim().substring(6);
 
-  const range = header.replace('bytes=', '').split('-');
-  const start = Number(range[0]) || 0;
-  const end = Number(range[1]) || Infinity;
+  let start, end;
+
+  if (range.startsWith('-')) {
+    end = length - 1;
+    start = length - 1 - Number(range.substring(1));
+  } else {
+    const [s, e] = range.split('-').map(Number);
+    start = s;
+    end = e || length - 1;
+  }
+
+  if (end > length - 1) {
+    end = length - 1;
+  }
 
   return [start, end];
 }

src/server/decorators/dbFile.ts

@@ -2,7 +2,7 @@ import { File } from '@prisma/client';
 import { FastifyInstance, FastifyReply } from 'fastify';
 import fastifyPlugin from 'fastify-plugin';
 import exts from 'lib/exts';
-import { parseRangeHeader } from 'lib/utils/range';
+import { parseRange } from 'lib/utils/range';
 
 function dbFileDecorator(fastify: FastifyInstance, _, done) {
   fastify.decorateReply('dbFile', dbFile);
@@ -17,28 +17,70 @@ function dbFileDecorator(fastify: FastifyInstance, _, done) {
     const size = await this.server.datasource.size(file.name);
     if (size === null) return this.notFound();
 
-    // eslint-disable-next-line prefer-const
-    let [rangeStart, rangeEnd] = parseRangeHeader(this.request.headers.range);
-    if (rangeStart >= rangeEnd)
-      return this.code(416)
-        .header('Content-Range', `bytes 0/${size - 1}`)
-        .send();
-    if (rangeEnd === Infinity) rangeEnd = size - 1;
-
-    const data = await this.server.datasource.get(file.name);
-
-    // only send content-range if the client asked for it
     if (this.request.headers.range) {
-      this.code(206);
-      this.header('Content-Range', `bytes ${rangeStart}-${rangeEnd}/${size}`);
+      const [start, end] = parseRange(this.request.headers.range, size);
+      if (start >= size || end >= size) {
+        const buf = await datasource.get(file.name);
+        if (!buf) return this.server.nextServer.render404(this.request.raw, this.raw);
+
+        return this.type(file.mimetype || 'application/octet-stream')
+          .headers({
+            'Content-Length': size,
+            ...(file.originalName
+              ? {
+                  'Content-Disposition': `${download ? 'attachment; ' : ''}filename="${encodeURIComponent(
+                    file.originalName,
+                  )}"`,
+                }
+              : download && {
+                  'Content-Disposition': 'attachment;',
+                }),
+          })
+          .status(416)
+          .send(buf);
+      }
+
+      const buf = await datasource.range(file.name, start || 0, end);
+      if (!buf) return this.server.nextServer.render404(this.request.raw, this.raw);
+
+      return this.type(file.mimetype || 'application/octet-stream')
+        .headers({
+          'Content-Range': `bytes ${start}-${end}/${size}`,
+          'Accept-Ranges': 'bytes',
+          'Content-Length': end - start + 1,
+          ...(file.originalName
+            ? {
+                'Content-Disposition': `${download ? 'attachment; ' : ''}filename="${encodeURIComponent(
+                  file.originalName,
+                )}"`,
+              }
+            : download && {
+                'Content-Disposition': 'attachment;',
+              }),
+        })
+        .status(206)
+        .send(buf);
     }
 
-    this.header('Content-Length', rangeEnd - rangeStart + 1);
-    this.header('Content-Type', download ? 'application/octet-stream' : file.mimetype);
-    this.header('Content-Disposition', `inline; filename="${encodeURI(file.originalName || file.name)}"`);
-    this.header('Accept-Ranges', 'bytes');
+    const data = await datasource.get(file.name);
+    if (!data) return this.server.nextServer.render404(this.request.raw, this.raw);
 
-    return this.send(data);
+    return this.type(file.mimetype || 'application/octet-stream')
+      .headers({
+        'Content-Length': size,
+        'Accept-Ranges': 'bytes',
+        ...(file.originalName
+          ? {
+              'Content-Disposition': `${download ? 'attachment; ' : ''}filename="${encodeURIComponent(
+                file.originalName,
+              )}"`,
+            }
+          : download && {
+              'Content-Disposition': 'attachment;',
+            }),
+      })
+      .status(200)
+      .send(data);
   }
 }
 

src/server/decorators/rawFile.ts

@@ -5,7 +5,7 @@ import fastifyPlugin from 'fastify-plugin';
 import { createBrotliCompress, createDeflate, createGzip } from 'zlib';
 import pump from 'pump';
 import { Transform } from 'stream';
-import { parseRangeHeader } from 'lib/utils/range';
+import { parseRange } from 'lib/utils/range';
 
 function rawFileDecorator(fastify: FastifyInstance, _, done) {
   fastify.decorateReply('rawFile', rawFile);
@@ -18,25 +18,41 @@ function rawFileDecorator(fastify: FastifyInstance, _, done) {
 
     const mimetype = await guess(extname(id).slice(1));
 
-    // eslint-disable-next-line prefer-const
-    let [rangeStart, rangeEnd] = parseRangeHeader(this.request.headers.range);
-    if (rangeStart >= rangeEnd)
-      return this.code(416)
-        .header('Content-Range', `bytes 0/${size - 1}`)
-        .send();
-    if (rangeEnd === Infinity) rangeEnd = size - 1;
-
-    const data = await this.server.datasource.get(id);
-
-    // only send content-range if the client asked for it
     if (this.request.headers.range) {
-      this.code(206);
-      this.header('Content-Range', `bytes ${rangeStart}-${rangeEnd}/${size}`);
+      const [start, end] = parseRange(this.request.headers.range, size);
+      if (start >= size || end >= size) {
+        const buf = await datasource.get(id);
+        if (!buf) return this.server.nextServer.render404(this.request.raw, this.raw);
+
+        return this.type(mimetype || 'application/octet-stream')
+          .headers({
+            'Content-Length': size,
+            ...(download && {
+              'Content-Disposition': 'attachment;',
+            }),
+          })
+          .status(416)
+          .send(buf);
+      }
+
+      const buf = await datasource.range(id, start || 0, end);
+      if (!buf) return this.server.nextServer.render404(this.request.raw, this.raw);
+
+      return this.type(mimetype || 'application/octet-stream')
+        .headers({
+          'Content-Range': `bytes ${start}-${end}/${size}`,
+          'Accept-Ranges': 'bytes',
+          'Content-Length': end - start + 1,
+          ...(download && {
+            'Content-Disposition': 'attachment;',
+          }),
+        })
+        .status(206)
+        .send(buf);
     }
 
-    this.header('Content-Length', rangeEnd - rangeStart + 1);
-    this.header('Content-Type', download ? 'application/octet-stream' : mimetype);
-    this.header('Accept-Ranges', 'bytes');
+    const data = await datasource.get(id);
+    if (!data) return this.server.nextServer.render404(this.request.raw, this.raw);
 
     if (
       this.server.config.core.compression.enabled &&
@@ -49,7 +65,16 @@ function rawFileDecorator(fastify: FastifyInstance, _, done) {
       )
         return this.send(useCompress.call(this, data));
 
-    return this.send(data);
+    return this.type(mimetype || 'application/octet-stream')
+      .headers({
+        'Content-Length': size,
+        'Accept-Ranges': 'bytes',
+        ...(download && {
+          'Content-Disposition': 'attachment;',
+        }),
+      })
+      .status(200)
+      .send(data);
   }
 }