fix(gateway): disable compression (#2245)

This is an alternative to #2227
that does not hit datastore twice.

The underlying error was caused by multiple PassThrough/pipe calls.
Turns out go-ipfs does not compress anything by default, so we can
remove PassThrough responsible for streaming of compressed payload
and fix the issue while keeping optimization introduced by buffer-peek-stream.

Closes libp2p/js-libp2p#374
Closes libp2p/pull-mplex#13

License: MIT
Signed-off-by: Marcin Rataj <lidel@lidel.org>

src/http/gateway/resources/gateway.js

@@ -6,7 +6,6 @@ log.error = debug('ipfs:http-gateway:error')
 
 const fileType = require('file-type')
 const mime = require('mime-types')
-const { PassThrough } = require('readable-stream')
 const Boom = require('@hapi/boom')
 const Ammo = require('@hapi/ammo') // HTTP Range processing utilities
 const peek = require('buffer-peek-stream')
@@ -32,20 +31,6 @@ function detectContentType (path, chunk) {
   return mime.contentType(mimeType)
 }
 
-// Enable streaming of compressed payload
-// https://github.com/hapijs/hapi/issues/3599
-class ResponseStream extends PassThrough {
-  _read (size) {
-    super._read(size)
-    if (this._compressor) {
-      this._compressor.flush()
-    }
-  }
-  setCompressor (compressor) {
-    this._compressor = compressor
-  }
-}
-
 module.exports = {
 
   async handler (request, h) {
@@ -149,7 +134,6 @@ module.exports = {
     }
 
     const rawStream = ipfs.catReadableStream(data.cid, catOptions)
-    const responseStream = new ResponseStream()
 
     // Pass-through Content-Type sniffing over initial bytes
     const { peekedStream, contentType } = await new Promise((resolve, reject) => {
@@ -163,9 +147,7 @@ module.exports = {
       })
     })
 
-    peekedStream.pipe(responseStream)
-
-    const res = h.response(responseStream).code(rangeResponse ? 206 : 200)
+    const res = h.response(peekedStream).code(rangeResponse ? 206 : 200)
 
     // Etag maps directly to an identifier for a specific version of a resource
     // and enables smart client-side caching thanks to If-None-Match

src/http/index.js

@@ -82,7 +82,11 @@ class HttpApi {
       // TODO: shouldn't, fix this
       routes: {
         cors: true
-      }
+      },
+      // Disable Compression
+      // Why? Streaming compression in Hapi is not stable enough,
+      // it requires bug-prone hacks such as https://github.com/hapijs/hapi/issues/3599
+      compression: false
     })
     server.app.ipfs = ipfs