-<!-- $Id: frontend.xml,v 1.16 2003-02-23 20:40:01 adam Exp $ -->
+<!-- $Id: frontend.xml,v 1.22 2004-03-19 21:12:13 adam Exp $ -->
<chapter id="server"><title>Generic server</title>
<sect1><title>Introduction</title>
<para>
If you have a database system that you would like to make available by
- means of Z39.50 or SRW, &yaz; basically offers your two options. You
+ means of Z39.50, SRW o SRU, &yaz; basically offers your two options. You
can use the APIs provided by the &asn;, &odr;, and &comstack;
modules to
create and decode PDUs, and exchange them with a client.
<note>
<para>
- The &yaz; server does not provide full SRW functionality.
- However, it provides an adapter for SRW (to Z39.50).
+ The &yaz; server does not support XCQL.
</para>
</note>
</sect1>
</para>
<para>
- This handler is also called when operating in SRW mode - when
- a connection has been made (even though SRW does not offer
+ This handler is also called when operating in SRW/SRU mode - when
+ a connection has been made (even though SRW/SRU does not offer
this service).
</para>
<para>
The <function>bend_search</function> handler is also called when
- the frontend server receives a SRW SearchRetrieveRequest.
- For SRW, a CQL query is usually provided by the client.
+ the frontend server receives a SRW/SRU SearchRetrieveRequest.
+ For SRW/SRU, a CQL query is usually provided by the client.
The CQL query is available as part of <literal>Z_Query</literal>
structure (note that CQL is now part of Z39.50 via an external).
To support CQL in existing implementations that only do Type-1,
<para>
To maintain backwards compatibility, the frontend server
of yaz always assume that error codes are BIB-1 diagnostics.
- For SRW operation, a Bib-1 diagnostic code is mapped to
- SRW diagnostic.
+ For SRW/SRU operation, a Bib-1 diagnostic code is mapped to
+ SRW/SRU diagnostic.
</para>
<synopsis>
int errcode; /* 0==success */
char *errstring; /* system error string or NULL */
int surrogate_flag; /* surrogate diagnostic */
+ char *schema; /* string record schema input/output */
} bend_fetch_rr;
</synopsis>
<para>
The frontend server calls the <function>bend_fetch</function> handler
when it needs database records to fulfill a Z39.50 Search Request, a
- Z39.50 Present Request or a SRW SearchRetrieveRequest.
+ Z39.50 Present Request or a SRW SearchRetrieveRequest.
The <literal>setname</literal> is simply the name of the result set
that holds the reference to the desired record.
The <literal>number</literal> is the offset into the set (with 1
being the first record in the set). The <literal>format</literal> field
- is the record format requested by the client (See section
- <link linkend="oid">Object Identifiers</link>). The value
- <literal>VAL_NONE</literal> indicates that the client did not
- request a specific format. The <literal>stream</literal> argument
+ is the record format requested by the client (See
+ <xref linkend="asn.oid"/>).
+ The value <literal>VAL_NONE</literal> indicates that the client did
+ not request a specific format. The <literal>stream</literal> argument
is an &odr; stream which should be used for
allocating space for structured data records.
The stream will be reset when all records have been assembled, and
</para>
<para>
- If a SRW SearchRetrieveRequest is received by the frontend server,
- the <literal>referenceId</literal> is NULL, the <literal>request_format
- </literal> (transfer syntax) is XML (OID name
+ If a SRW/SRU SearchRetrieveRequest is received by the frontend server,
+ the <literal>referenceId</literal> is NULL and the
+ <literal>request_format</literal> (transfer syntax) is XML (OID name
<literal>VAL_TEXT_XML</literal>).
- The schema for SRW is stored in the
+ The schema for SRW/SRU is stored in both the
<literal>Z_RecordComposition</literal>
- structure.
+ structure and <literal>schema</literal> (simple string).
</para>
<para>
database that holds the
record. <literal>len</literal> is the length of the record returned, in
bytes, and <literal>record</literal> is a pointer to the record.
- <literal>Last_in_set</literal> should be nonzero only if the record
+ <literal>last_in_set</literal> should be nonzero only if the record
returned is the last one in the given result set.
<literal>errcode</literal> and <literal>errstring</literal>, if
given, will be interpreted as a global error pertaining to the
<cmdsynopsis>
<command>appname</command>
+ <arg choice="opt"><option>-install</option></arg>
+ <arg choice="opt"><option>-installa</option></arg>
+ <arg choice="opt"><option>-remove</option></arg>
<arg choice="opt"><option>-a <replaceable>file</replaceable></option></arg>
<arg choice="opt"><option>-v <replaceable>level</replaceable></option></arg>
<arg choice="opt"><option>-l <replaceable>file</replaceable></option></arg>
<arg choice="opt"><option>-k <replaceable>kilobytes</replaceable></option></arg>
<arg choice="opt"><option>-d <replaceable>daemon</replaceable></option></arg>
<arg choice="opt"><option>-w <replaceable>dir</replaceable></option></arg>
- <arg choice="opt"><option>-ziST1</option></arg>
+ <arg choice="opt"><option>-p <replaceable>pidfile</replaceable></option></arg>
+ <arg choice="opt"><option>-ziDST1</option></arg>
<arg choice="opt" rep="repeat">listener-spec</arg>
</cmdsynopsis>
<synopsis>
hostname | IP-number [: portnumber]
</synopsis>
-
+
<para>
The port number defaults to 210 (standard Z39.50 port).
</para>
</para>
<para>
- For TCP/IP and SSL, the special hostname "@" is mapped to
- the address <literal>INADDR_ANY</literal>, which causes the
- server to listen on any local interface.
- </para>
-
- <para>
- Examples:
- <screen>
- tcp:@:210
-
- ssl:@:3000
-
- unix:/tmp/yaz
- </screen>
+ For TCP/IP and SSL, the special hostname <literal>@</literal>
+ (at sign) is mapped to the address <literal>INADDR_ANY</literal>,
+ which causes the server to listen on any local interface.
</para>
+ <example><title>Running the GFS on Unix</title>
+ <para>
+ Assuming the server application <replaceable>appname</replaceable> is
+ started as root, the following will make it listen on port 210.
+ The server will change identity to <literal>nobody</literal>
+ and write its log to <filename>/var/log/app.log</filename>.
+ <screen>
+ <replaceable>appname</replaceable> -l /var/log/app.log -u nobody tcp:@:210
+ </screen>
+ </para>
+ <para>
+ The server will accept Z39.50 requests and offer SRW/SRU service
+ on port 210.
+ </para>
+ </example>
+ <example><title>Setting up Apache as SRW/SRU Frontend</title>
+ <para>
+ If you use <ulink url="http://httpd.apache.org/">Apache</ulink>
+ as your public web server and want to offer HTTP port 80
+ access to the YAZ server on 210, you can use the
+ <ulink url="http://httpd.apache.org/docs/mod/mod_proxy.html#proxypass">
+ <literal>ProxyPass</literal></ulink>
+ directive.
+ If you have virtual host
+ <literal>srw.mydomain</literal> you can use the following directives
+ in Apache's httpd.conf:
+ <screen>
+ <VirtualHost *>
+ ErrorLog /home/srw/logs/error_log
+ TransferLog /home/srw/logs/access_log
+ ProxyPass / http://srw.mydomain:210/
+ </VirualHost>
+ </screen>
+ </para>
+ <para>
+ The above for the Apache 1.3 series.
+ </para>
+ </example>
+ <example><title>Running a server with local access only</title>
+ <para>
+ Servers that is only being accessed from the local host should listen
+ on UNIX file socket rather than a Internet socket. To listen on
+ <filename>/tmp/mysocket</filename> start the server as follows:
+ <screen>
+ <replaceable>appname</replaceable> tcp:/tmp/mysocket
+ </screen>
+ </para>
+ </example>
</sect1>
</chapter>