To be covered:

1. HTTP service as program paradigm
2. The HTTP toolkit supports the HTTP object
3. HTTP toolkit: object properties
4. New concepts
5. /factory services
6. A microserver example: ethanol
7. A full-featured example: logpstar
8. Other cool stuff.
9. ... in conclusion ...

1.  HTTP service as program paradigm

• Requirements

  • Full-strength delivery of GUI to all kinds of clients

  • Non-GUI application programs would be nice, too.

  • Network orientation for integration as a tool

  • Administration-free program delivery

  • Secure operations in a (mainly) stateless environment

  • Scale from one machine to LAN to enterprise to www

  • Robust. Reliable. Testable. Supportable.

• Compelling motivations

  • MIT-X/XView limited future, limited audience

  • DCGI right direction but not supportable in long run

  • Current information delivery is limited by interfaces

  • "Bite the bullet and do it right" is a long term winner

2.  The HTTP toolkit supports the HTTP object

• An HTTP object represents an HTTP service

• dt_http_alloc() creates one

• dt_http_loop() starts it

• dt_dealloc() destroys it

• Everything else is controlled by object properties

3.  HTTP toolkit: object properties

• Factory properties are in the "_" namespace

• Very few properties needed for basic operation:
  • "_path" -- request path
  • "_reply" -- reply content
  • "_mime" -- reply type

• Large number of properties allow complete control

• Object-property API is likely basis of Daylight 5.x

4.  New concepts

• Daylight methods

  The HTTP toolkit requires the introduction of object methods to the Daylight toolkit API. In the HTTP toolkit these serve as callbacks, but methods may be used for many other purposes also. The HTTP toolkit defines five such methods as HTTP object properties (_init_cb, _loop_cb, _beat_cb, _error_cb, _exit_cb). Of these, only one (_loop_cb) is needed for basic operation.

• Service domain

  This is something that ought to be part of the HTTP protocol, but it doesn't seem to be, so it was invented as part of the HTTP toolkit. A service domain is simply a set of IPs which an HTTP server will service. It may be a network or a list of IPs. The default service domain is the server's own (A-, B-, or C-class) network, but it can be set like any other HTTP object property to, for instance, a subnet or www. HTTP requests originating from outside the service domain get a 403 Forbidden response.

5.  /factory services

• /factory/etc/
  current status and object property information

• /factory/help/
  documentation about HTTP toolkit and server usage

• /factory/image/
  static images such as the Daylight sunburst logo

• /factory/java/ and /factory/javascript/
  .jar, Class and .js resources

6.  A microserver example: ethanol

$ make ethanol
/opt/SUNWspro/bin/cc -v -Xc -DDP_SOLARIS -D_POSIX_PTHREAD_SEMANTICS -D_REEN
...
$ strip ethanol
$ ls -l ethanol
-rwxr-xr-x   1 dave     staff       6748 Feb 23 17:29 ethanol
$ ./ethanol
ethanol server starting up on port 22002

And the link <A HREF='http://sun2.daylight.com:22002/'>.

The small size of the executable (6748 bytes) is due to linking against the SMILES and HTTP libraries in run time ... but any way you cut it, those are 6748 hard-working bytes! Simple as this example is, it meets the ambitious requirements listed at the beginning of this talk.

7.  A full-featured example: logpstar

<A HREF='http://sun2.daylight.com:11053/'>.

8.  Other cool stuff

• Forms

  Data from posted forms are available as a sequence of name-value pairs as the _posts request property.

• File upload

  Multipart encoding is supported to allow file upload from the client's machine. Data is provided as a normal posted property _value. Additionally, the "_filename" property is defined.

• Cookies

  Netscape cookies are supported to provide a limited amount of state information. Default or user-provided encryption is supported.

• Authorization

  HTTP 2.0 challenge/authentication protocol is supported.

9.  ... in conclusion ...

• The HTTP toolkit provides a powerful method for dissemination of research information.
• The HTTP toolkit is integrated into the Daylight system and behaves similarly to other toolkits.
• The HTTP toolkit is slated to be part of Daylight Release 4.81.