shunner / yazproxy

This fork is just for the purpose of learning and testing GitHub features,

YAZ proxy - A Z39.50/SRU proxy.

Introduction

ahaahahha
add something.
edited by yuyue
edited by joseph

YAZ proxy is a powerful general purpose Z39.50/SRU proxy.
The proxy application and development library is covered by the
GPL - see LICENSE for details.

Documentation
-------------

The "doc" directory contains documentation in HTML and PDF.
You can also read it online at http://www.indexdata.dk/yazproxy/

Overview
--------

YAZ proxy builds a programmers' library libyazproxy.lib and a
proxy application.

Directory structure of the YAZ++ package:

  -- src (YAZ proxy library and application)
  -- include/yazproxy (C++ headers for proxy) 
  -- win (Windows build files)
  -- doc (DocBook-format documentation)
  -- etc (Proxy config + XSLT files)

About the proxy
---------------

For the proxy the actual target is determined in by the OtherInfo
part of the InitRequest. We've defined an OID for this which we call
PROXY. The OID is 1.2.840.10003.10.1000.81.1. 

  OtherInformation   ::= [201] IMPLICIT SEQUENCE OF SEQUENCE{
    category           [1]   IMPLICIT InfoCategory OPTIONAL, 
    information        CHOICE{
      characterInfo            [2]  IMPLICIT InternationalString,
      binaryInfo               [3]  IMPLICIT OCTET STRING,
      externallyDefinedInfo    [4]  IMPLICIT EXTERNAL,
      oid                      [5]  IMPLICIT OBJECT IDENTIFIER}}
--
  InfoCategory ::= SEQUENCE{
      categoryTypeId   [1]   IMPLICIT OBJECT IDENTIFIER OPTIONAL,
      categoryValue    [2]   IMPLICIT INTEGER}

The InfoCategory is present with categoryTypeId set to the PROXY OID
and categoryValue set to 1. The information in OtherInformation uses
characterInfo to represent the target using the form target[:port][/db].

For clients that don't set the PROXY OtherInformation, a default
target can be specified using option -t for proxy.

Example:
  We start the proxy so that it listens on port 9000. The default
  target is Bell Labs Library unless it is overridden by a client in
  the InitRequest.

     $ ./yaz-proxy -t z3950.bell-labs.com/books @:9000

  The client is started and talks to the proxy without specifying
  a target. Hence this client will talk to the Bell Labs server.

     $ ./yaz-client localhost:9000

  The client is started and it specifies the actual target itself.

     $ ./yaz-client -p localhost:9000 bagel.indexdata.dk/gils

  For ZAP the equivalent would be
     proxy=localhost:9000
     target=bagel.indexdata.dk/gils
  Simple, huh!