yaz-ztest - Z39.50/SRU Test Server


   application [-install] [-installa] [-remove] [-a file] [-v level]
               [-l file] [-u uid] [-c config] [-f vconfig] [-C fname]
               [-t minutes] [-k kilobytes] [-K] [-d daemon] [-w dir]
               [-p pidfile] [-r kilobytes] [-ziDST1] [listener-spec...]


   yaz-ztest is a Z39.50/SRU test server that uses the YAZ generic
   frontend server (GFS) API. The server acts as a real Z39.50/SRU server
   but does not use a database. It returns a random hit count and returns
   a subset of a few built-in records.

   The listener-spec consists of a transport mode followed by a colon,
   followed by a listener address. The transport mode is either tcp, unix,
   or ssl.

   For TCP and SSL, an address has the form:

           hostname | IP-number [ : portnumber ]

   For UNIX local socket the address is the filename of the local socket.


   -a file
       Specify a file for dumping PDUs (for diagnostic purposes). The
       special name - (dash) sends output to stderr.

       Don't fork or make threads on connection requests. This is good for
       debugging, but not recommended for real operation: Although the
       server is asynchronous and non-blocking, it can be nice to keep a
       software malfunction (okay then, a crash) from affecting all
       current users.

       Like -S but after one session the server exits. This mode is for
       debugging only.

       Operate the server in threaded mode. The server creates a thread
       for each connection rather than a fork a process. Only available on
       UNIX systems that offers POSIX threads.

       Use the SR protocol (obsolete).

       Use the Z39.50 protocol (default). This option and -s complement
       each other. You can use both multiple times on the same command
       line, between listener-specifications (see below). This way, you
       can set up the server to listen for connections in both protocols
       concurrently, on different local ports.

   -l file
       The logfile.

   -c config
       A user option that serves as a specifier for some sort of
       configuration, usually a filename. The argument to this option is
       transferred to member configname of the statserv_options_block.

   -f vconfig
       This specifies an XML file that describes one or more YAZ frontend
       virtual servers.

   -C fname
       Sets SSL certificate file name for server (PEM).

   -v level
       The log level. Use a comma-separated list of members of the set

   -u uid
       Set user ID. Sets the real UID of the server process to that of the
       given user. It's useful if you aren't comfortable with having the
       server run as root, but you need to start it as such to bind a
       privileged port.

   -w dir
       The server changes to this directory during before listening on
       incoming connections. This option is useful when the server is
       operating from the inetd daemon (see -i).

   -p pidfile
       Specifies that the server should write its Process ID to file given
       by pidfile. A typical location would be /var/run/yaz-ztest.pid.

       Use this to make the the server run from the inetd server (UNIX

       Use this to make the server put itself in the background and run as
       a daemon. If neither -i nor -D is given, the server starts in the

       Use this to install the server as an NT service (Windows NT/2000/XP
       only). Control the server by going to the Services in the Control

       Use this to install and activate the server as an NT service
       (Windows NT/2000/XP only). Control the server by going to the
       Services in the Control Panel.

       Use this to remove the server from the NT services (Windows
       NT/2000/XP only).

   -t minutes
       Idle session timeout, in minutes.

   -k size
       Maximum record size/message size, in kilobytes.

       Forces no-keepalive for HTTP sessions. By default GFS will keep
       sessions alive for HTTP 1.1 sessions (as defined by the standard).
       Using this option will force GFS to close the connection for each

   -r size
       Maximum size of log file before rotation occurs, in kilobytes.
       Default size is 1048576 k (=1 GB).

   -d daemon
       Set name of daemon to be used in hosts access file. See
       hosts_access(5) and tcpd(8).

   -m time-format
       Sets the format of time-stamps in the log-file. Specify a string in
       the input format to strftime().


   yaz-ztest normally returns a random hit count between 0 and 24.
   However, if a query term includes leading digits, then the integer
   value of that term is used as hit count. This allows testers to return
   any number of hits.  yaz-ztest includes 24 MARC records for testing.
   Hit counts exceeding 24 will make yaz-ztest return the same record
   batch over and over.. So record at position 1, 25, 49, etc .. are

   The following databases are honored by yaz-ztest: Default, slow and
   db.*  (all databases with prefix "db"). Any other database will make
   yaz-ztest return diagnostic 109: "Database unavailable".

   Options for search may be included in the form or URL get arguments
   included as part of the Z39.50 database name. The following database
   options are present: search-delay, present-delay, fetch-delay and seed.

   The former, delay type options, specify a fake delay (sleep) that
   yaz-ztest will perform when searching, presenting, fetching records
   respectively. The value of the delay may either be a fixed floating
   point value which specifies the delay in seconds. Alternatively the
   value may be given as two floating point numbers separated by colon,
   which wil make yaz-ztest perform a random sleep between the first and
   second number.

   The database parameter seed takes an integer as value. This will call
   srand with this integer to ensure that the random behavior can be

   Suppose we want searches to take between 0.1 and 0.5 seconds and a
   fetch to take 0.2 second. To access test database Default we'd use:


   The Virtual hosts mechanism allows a YAZ frontend server to support
   multiple backends. A backend is selected on the basis of the TCP/IP
   binding (port+listening adddress) and/or the virtual host.

   A backend can be configured to execute in a particular working
   directory. Or the YAZ frontend may perform CQL to RPN conversion, thus
   allowing traditional Z39.50 backends to be offered as a SRW/SRU
   service. SRW/SRU Explain information for a particular backend may also
   be specified.

   For the HTTP protocol, the virtual host is specified in the Host
   header. For the Z39.50 protocol, the virtual host is specified as in
   the Initialize Request in the OtherInfo, OID

       Not all Z39.50 clients allows the VHOST information to be set. For
       those the selection of the backend must rely on the TCP/IP
       information alone (port and address).

   The YAZ frontend server uses XML to describe the backend
   configurations. Command-line option -f specifies filename of the XML

   The configuration uses the root element yazgfs. This element includes a
   list of listen elements, followed by one or more server elements.

   The listen describes listener (transport end point), such as TCP/IP,
   Unix file socket or SSL server. Content for a listener:

   CDATA (required)
       The CDATA for the listen element holds the listener string, such as
       tcp:@:210, tcp:server1:2100, etc.

   attribute id (optional)
       identifier for this listener. This may be referred to from server

       We expect more information to be added for the listen section in a
       future version, such as CERT file for SSL servers.

   The server describes a server and the parameters for this server type.
   Content for a server:

   attribute id (optional)
       Identifier for this server. Currently not used for anything, but it
       might be for logging purposes.

   attribute listenref (optional)
       Specifies listener for this server. If this attribute is not given,
       the server is accessible from all listener. In order for the server
       to be used for real, howeever, the virtual host must match (if
       specified in the configuration).

   element config (optional)
       Specifies the server configuration. This is equivalent to the
       config specified using command line option -c.

   element directory (optional)
       Specifies a working directory for this backend server. If specifid,
       the YAZ fronend changes current working directory to this directory
       whenever a backend of this type is started (backend handler
       bend_start), stopped (backend handler hand_stop) and initialized

   element host (optional)
       Specifies the virtual host for this server. If this is specified a
       client must specify this host string in order to use this backend.

   element cql2rpn (optional)
       Specifies a filename that includes CQL to RPN conversion for this
       backend server. See ???  If given, the backend server will only
       "see" a Type-1/RPN query.

   element ccl2rpn (optional)
       Specifies a filename that includes CCL to RPN conversion for this
       backend server. See ???  If given, the backend server will only
       "see" a Type-1/RPN query.

   element stylesheet (optional)
       Specifies the stylesheet reference to be part of SRU HTTP responses
       when the client does not specify one. If neither this is given, nor
       the client specifies one, no stylesheet reference is part of the
       SRU HTTP response.

   element docpath (optional)
       Specifies a path for local file access using HTTP. All URLs with a
       leading prefix (/ exluded) that matches the value of docpath are
       used for file access. For example, if the server is to offer access
       in directory xsl, the docpath would be xsl and all URLs of the form
       http://host/exl will result in a local file access.

   element explain (optional)
       Specifies SRW/SRU ZeeRex content for this server. Copied verbatim
       to the client. As things are now, some of the Explain content seeem
       redundant because host information, etc. is also stored elsewhere.

   element maximumrecordsize (optional)
       Specifies maximum record size/message size, in bytes. This value
       also servers as maximum size of incoming packages (for Record
       Updates etc). It's the same value as that given by the -k option.

   element retrievalinfo (optional)
       Enables the retrieval facility supporting conversions and
       specifications of record formats/types. See ???  for more

   The XML below configures a server that accepts connections from two
   ports, TCP/IP port 9900 and a local UNIX file socket. We name the
   TCP/IP server public and the other server internal.

         <listen id="public">tcp:@:9900</listen>
         <listen id="internal">unix:/var/tmp/socket</listen>
         <server id="server1">
         <server id="server2">
           <explain xmlns="http://explain.z3950.org/dtd/2.0/">
         <server id="server3" listenref="internal">

   There are three configured backend servers. The first two servers,
   "server1" and "server2", can be reached by both listener addresses -
   since no listenref attribute is specified. In order to distinguish
   between the two a virtual host has been specified for each of server in
   the host elements.

   For "server2" elements for CQL to RPN conversion is supported and
   explain information has been added (a short one here to keep the
   example small).

   The third server, "server3" can only be reached via listener





   yaz(7) yaz-log(7)


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