LT at Shibuya.apk #22 Introduction to how to make Android Device an HTTP server. Demo app is available at my GitHub repository below. https://github.com/chooyan-eng/AndroidHttpServerDemo

1. Can Android be an HTTP Server?
2018.02.06 Tue.
Tsuyoshi Chujo
@ shibuya.apk # 22

2. About me
Tsuyoshi Chujo
● Freelance engineer of Web services
○ Android, Web server (Servlet, Django, Ruby on Rails), etc.
● Currently, working as an Android developer in a manufacturer
● Social Accounts
○ Qiita: @chooyan-eng
○ GitHub: @chooyan-eng
○ dev.to: @chooyan
○ Twitter: @chooyan_i18n
● CodeYourRuby the device powered by Android
(but NOT a Smart Phone)

3. Can Android be an HTTP Server?
Ordinal architecture
Client Server
request
response

4. Can Android be an HTTP Server?
What I would like to discuss today
Client
Server
request
response

5. YES! Android CAN be an HTTP Server!
● HTTP is based on TCP
● HTTP is a protocol of “How to Control TCP”
○ See OSI or TCP/IP in detail
● All the OS (as far as I know) can use TCP. It’s the function of OS.
● Android OS also can use TCP
● Thus, Android device can be a HTTP server by extending TCP and
implementing the specification on RFC 7230.

6. How to implement?
● Use java.net.ServerSocket
○ Basic class to accept requests based on TCP/IP protocol
○ InputStream and OutputStream of this class presents TCP Socket.
○ See my GitHub repository if you are interested in usage.

7. Flow Image
Client Server
open socket
connect accept
GET / HTTP/1.1CRLFUser-Agent: XXXXCRLFCookie:...
parse and calculate the
end of data.
do something...
Then, send back
response.receive data
and parse
send data
HTTP/1.1 200 OKCRLFContent-Type: text/htmlCRLF...
establish connection

8. Demo
if app does not work… see below :-(
https://www.youtube.com/watch?v=_hZ_UsFKnIU
Open the URL below with your favorite web browser :-)
http://XXX.XXX.XXX.XXX:20000
https://github.com/chooyan-eng/AndroidHttpServerDemo

9. When to Use? (in my experience)
● Embedded Android (Android on devices for specific operation)
○ Send data DIRECTLY from PC to Android devices via LAN.
○ Send data with TCP connection. (Not using HTTP, but basic idea is the same as discussion here)
end data
and control the device
response

10. Thank you!