• This repository has been archived on 02/Nov/2021
  • Stars
    star
    2,395
  • Rank 18,355 (Top 0.4 %)
  • Language
    Objective-C
  • License
    Apache License 2.0
  • Created over 10 years ago
  • Updated about 7 years ago

Reviews

There are no reviews yet. Be the first to send feedback to the community and the maintainers!

Repository Details

SPDY for iOS and OS X

CocoaSPDY

A SPDY/3.1 framework for iOS and Mac OS X

Branch Build Code Coverage
master Build Status Coverage Status
develop Build Status Coverage Status

Download v1.2

The SPDY protocol

The short version is that SPDY can make your HTTP requests faster. Sometimes a lot faster. For more details, see the following:

http://www.chromium.org/spdy/spdy-whitepaper
http://www.chromium.org/spdy/spdy-protocol/spdy-protocol-draft3-1

SPDY was originally designed at Google as an experimental successor to HTTP. It's a binary protocol (rather than human-readable, like HTTP), but is fully compatible with HTTP. In fact, current draft work on HTTP/2.0 is largely based on the SPDY protocol and its real-world success.

In order to make HTTP requests go faster SPDY makes several improvements:

The first, and arguably most important, is request multiplexing. Rather than sending one request at a time over one TCP connection, SPDY can issue many requests simultaneously over a single TCP session and handle responses in any order, as soon as they're available.

Second, SPDY compresses both request and response headers. Headers are often nearly identical to each other across requests, generally contain lots of duplicated text, and can be quite large. This makes them an ideal candidate for compression.1

Finally, SPDY introduces server push.2 This can allow a server to push content that the client doesn't know it needs yet. Such content can range from additional assets like styles and images, to notifications about realtime events.

  1. Please see the note below about the CRIME attack.
  2. Not currently supported in this framework, but coming soon.

Getting Started

The SPDY framework is designed to work seamlessly with your existing apps and projects. If you are using the NSURL stack to issue requests (or any library that provides an abstraction over it, like AFNetworking), you can simply add the SPDY framework bundle to your project, link it to your targets, and enable the protocol.

The framework contains a multi-architecture/multi-platform ("fat") binary that supports versions of iOS 6 and above, and OS X Lion and above, as well as all hardware capable of running those operating systems. When you distribute your application, the size of the included binary will be dramatically reduced, provided you have code stripping enabled.

Enabling SPDY

To use the SPDY framework you'll need to link CFNetwork.framework and libz.dylib in your project. This can be done in the "Link Binary with Libraries" section under "Build Phases" for your compilation target.

The way you enable SPDY in your application will be slightly different depending on whether you are using NSURLConnection or NSURLSession to manage your HTTP calls. In order to cause requests issued via the NSURLConnection stack to be carried over SPDY, you'll make a method call to specify one or more origins (protocol-host-port tuple) to be handled by SPDY:

#import <SPDY/SPDYProtocol.h>
...
[SPDYURLConnectionProtocol registerOrigin:@"https://api.twitter.com:443"];

Note that origins containing "http" vs. "https" are distinct from each other, will be handled by separate SPDY sessions, and must be registered independently. Only sessions for origins containing "https" will be encrypted with TLS.

For NSURLSession, you can configure sessions to use SPDY via NSURLSessionConfiguration:

#import <SPDY/SPDYProtocol.h>
...
NSURLSessionConfiguration *configuration = [NSURLSessionConfiguration defaultSessionConfiguration];
configuration.protocolClasses = @[[SPDYURLSessionProtocol class]];

You can freely use either or both methods, and existing SPDY sessions will be shared across both networking stacks. If you do use the former approach, note that registered origins will also be handled by SPDY with the default NSURLSession.

Either of the above one-liners is all you need to do to shift HTTP requests transparently over to SPDY. Of course you still need a server that speaks SPDY! Some possibilities are:

A note on NPN

Most existing SPDY implementations use a TLS extension called Next Protocol Implementation (NPN) to negotiate SPDY instead of HTTP. Unfortunately, this extension isn't supported by Secure Transport (Apple's TLS implementation), and so in order to use SPDY in your application, you'll either need to issue requests to a server that's configured to speak SPDY on a dedicated port, or use a server that's smart enough to examine the incoming request and determine whether the connection will be SPDY or HTTP based on what it looks like. At Twitter we do the latter, but the former solution may be simpler for most applications.

In order to aid with protocol inference, this SPDY implementation includes a non-standard settings id at index 0: SETTINGS_MINOR_VERSION. This is necessary to differentiate between SPDY/3 and SPDY/3.1 connections that were not negotiated with NPN, since only the major version is included in the frame header. Because not all servers may support this particular setting, sending it can be disabled at runtime through protocol configuration.

Implementation Notes

CRIME attack

The CRIME attack is a plaintext injection technique that exploits the fact that information can be inferred from compressed content length to potentially reveal the contents of an encrypted stream. This is a serious issue for browsers, which are subject to hijacks that may allow an attacker to issue an arbitrary number of requests with known plaintext header content and observe the resulting effect on compression.

In the context of an application that doesn't issue arbitrary requests, this is less likely to be an issue. However, before you ship a project with header compression enabled, you should understand the details of this attack and whether your application could be vulnerable.

Building the Framework Yourself

If you wish to compile the framework yourself, the process is fairly straightforward, and the build process should just work out of the box in Xcode. However, there are still a couple of things to note.

Prior to Xcode 5, if you wanted to compile the framework to a dual-platform binary (as in the distribution version), you were required to set 'iOS Device' as your platform target for the framework. This was due to a quirk in the Xcode build process that would otherwise exclude some (but not all) versions of the ARM architecture from the final binary. With the release of Xcode 5, any platform target should result in the same final universal binary (the setting is essentially ignored).

To create this binary, the build process actually depends on several static library targets and uses lipo to combine them.

Getting involved and Future work

We are always looking for people to get involved with the project.

In the near future, we will be working on:

Adopters

Please feel free to send us a pull request to add yourself to this list (bonus points to link to a tweet).

Problems?

If you find any issues please report them or better, send a pull request.

Authors

License

Copyright 2014 Twitter, Inc. and other contributors.

Licensed under the Apache License, Version 2.0: http://www.apache.org/licenses/LICENSE-2.0

More Repositories

1

snowflake

Snowflake is a network service for generating unique ID numbers at high scale with some simple guarantees.
Scala
7,566
star
2

diffy

Find potential bugs in your services with Diffy
Scala
3,827
star
3

flockdb

A distributed, fault-tolerant graph database
Scala
3,326
star
4

kestrel

simple, distributed message queue system (inactive)
Scala
2,780
star
5

twui

A UI framework for Mac based on Core Animation
Objective-C
2,750
star
6

gizzard

[Archived] A flexible sharding framework for creating eventually-consistent distributed datastores
Scala
2,255
star
7

distributedlog

A high performance replicated log service. (The development is moved to Apache Incubator)
Java
2,227
star
8

recess

A simple and attractive code quality tool for CSS built on top of LESS
CSS
2,190
star
9

commons

Twitter common libraries for python and the JVM (deprecated)
Java
2,102
star
10

iago

A load generator, built for engineers
Scala
1,351
star
11

twitter-text-js

A JavaScript implementation of Twitter's text processing library
1,212
star
12

ambrose

A platform for visualization and real-time monitoring of data workflows
Java
1,180
star
13

twitter-kit-android

Twitter Kit for Android
Java
827
star
14

ostrich

A stats collector & reporter for Scala servers (deprecated)
Scala
774
star
15

twitter-kit-ios

Twitter Kit is a native SDK to include Twitter content inside mobile apps.
Objective-C
684
star
16

twitter-text-rb

A library that does auto linking and extraction of usernames, lists and hashtags in tweets
617
star
17

mysos

Cotton (formerly known as Mysos)
592
star
18

twitter-text-objc

An Objective-C implementation of Twitter's text processing library
587
star
19

torch-autograd

Autograd automatically differentiates native Torch code
Lua
555
star
20

ospriet

An example audience moderation app built on Twitter
JavaScript
408
star
21

cloudhopper-smpp

Efficient, scalable, and flexible Java implementation of the Short Messaging Peer to Peer Protocol (SMPP)
Java
384
star
22

twitter-text-java

A Java implementation of Twitter's text processing library
363
star
23

jvmgcprof

A simple utility for profile allocation and garbage collection activity in the JVM
C
342
star
24

css-flip

A CSS BiDi flipper
JavaScript
313
star
25

clockworkraven

Human-Powered Data Analysis with Mechanical Turk
Ruby
299
star
26

torch-twrl

Torch-twrl is a package that enables reinforcement learning in Torch.
Lua
251
star
27

cassie

A Scala client for Cassandra
Scala
243
star
28

twemperf

A tool for measuring memcached server performance
C
242
star
29

hdfs-du

Visualize your HDFS cluster usage
JavaScript
231
star
30

pycascading

A Python wrapper for Cascading
Python
223
star
31

RTLtextarea

Automatically detects RTL and configures a text input
JavaScript
170
star
32

haplocheirus

A Redis-backed storage engine for timelines
Scala
133
star
33

standard-project

A slightly more standard sbt project plugin library
Scala
132
star
34

torch-decisiontree

This project implements random forests and gradient boosted decision trees (GBDT). The latter uses gradient tree boosting. Both use ensemble learning to produce ensembles of decision trees (that is, forests).
Lua
125
star
35

torch-ipc

A set of primitives for parallel computation in Torch
C
96
star
36

elephant-twin

Elephant Twin is a framework for creating indexes in Hadoop
Java
96
star
37

torch-distlearn

A set of distributed learning algorithms for Torch
Lua
95
star
38

libcrunch

A lightweight mapping framework that maps data objects to a number of nodes, subject to constraints
Java
90
star
39

scribe

A Ruby client library for Scribe
Ruby
89
star
40

sbt-package-dist

sbt 11 plugin codifying best practices for building, packaging, and publishing
Scala
88
star
41

twisitor

A simple and spectacular photo-tweeting birdhouse
JavaScript
84
star
42

code-of-conduct

Open Source Code of Conduct at Twitter
83
star
43

flockdb-client

A Ruby client library for FlockDB
Ruby
83
star
44

twitter-text-conformance

Conformance testing data for the twitter-text-* repositories
77
star
45

torch-dataset

An extensible and high performance method of reading, sampling and processing data for Torch
Lua
77
star
46

naggati2

Protocol builder for netty using scala (DEPRECATED)
Scala
74
star
47

cdk

CDK is a tool to quickly generate single-file html slide presentations from AsciiDoc
CSS
73
star
48

twitter-kit-unity

Twitter Kit for Unity
C#
71
star
49

plumage.js

Batteries Included App Framework for Data Intensive UIs
JavaScript
66
star
50

gozer

Prototype mesos framework using new low-level API built in Go
Go
61
star
51

bookkeeper

Twitter's fork of Apache BookKeeper (will push changes upstream eventually)
Java
60
star
52

grabby-hands

A JVM Kestrel client that aggregates queues from multiple servers. Implemented in Scala with Java bindings. In use at Twitter for all JVM Search and Streaming Kestrel interactions.
Scala
56
star
53

gizzmo

A command-line client for Gizzard
Ruby
54
star
54

thrift

Twitter's out-of-date, forked thrift
C++
52
star
55

libkestrel

libkestrel
Scala
47
star
56

time_constants

Time constants, in seconds, so you don't have to use slow ActiveSupport helpers
Ruby
46
star
57

sbt-scrooge

An SBT plugin that adds a mixin for doing Thrift code auto-generation during your compile phase
Scala
44
star
58

cli-guide.js

CLI Guide JQuery Plugin
JavaScript
41
star
59

sbt-thrift

sbt rules for generating source stubs out of thrift IDLs, for java & scala
Ruby
37
star
60

jaqen

A type-safe heterogenous Map or a Named field Tuple
Scala
35
star
61

spitball

A very simple gem package generation tool built on bundler
Ruby
33
star
62

torch-thrift

A Thrift codec for Torch
C
30
star
63

jsr166e

JSR166e for Twitter
Java
27
star
64

unishark

Unishark: Another unittest extension for Python
Python
26
star
65

raggiana

A simple standalone Finagle stats viewer
JavaScript
21
star
66

sekhmet

foundational tools and building blocks for gaining insights and diagnosing system health in real-time
20
star
67

periscope-live-engagement-unity-sdk

Periscope Live Engagement Unity SDK
C#
20
star
68

twitterActors

Improved Scala actors library; used internally at Twitter
Scala
18
star
69

finatra-activator-http-seed

Typesafe activator template for constructing a Finatra HTTP server application:
Scala
18
star
70

killdeer

Killdeer is a simple server for replaying a sample of responses to sythentically recreate production response characteristics.
Scala
15
star
71

bittern

Bittern Cache uses nvdimm to speed up block io operations
C
14
star
72

elephant-twin-lzo

Elephant Twin LZO uses Elephant Twin to create LZO block indexes
Java
14
star
73

finatra-activator-thrift-seed

Typesafe activator template for constructing a Finatra Thrift server application: https://twitter.github.io/finatra/user-guide/ β€”
Scala
11
star
74

chainsaw

A thin Scala wrapper for SLF4J
Scala
9
star
75

PerfTracepoint

Perf tracepoint support for the JVM
Java
7
star
76

oscon-puzzles

OSCON 2014 Puzzle
JavaScript
7
star
77

scala-json

JSON in Scala (deprecated)
Scala
5
star
78

scala-csp-config

A Scala library for configuring Content Security Policy headers for HTTP responses.
Scala
4
star
79

finatra-misc

Miscellaneous libraries and utils used by Finatra
Scala
3
star
80

.github

2
star
81

autolog-clustering

USF Capstone Project for Auto-log Clustering
Python
1
star