ESTNODE(3)                      Hyper Estraier                      ESTNODE(3)



NAME
       estnode.h - the node API of Hyper Estraier


SYNOPSIS
       #include <estraier.h>
       #include <estnode.h>
       #include <cabin.h>
       #include <stdlib.h>


API FOR INITIALIZING
       For preparation to use the node API, initialize the network environment
       at the beginning of a program.  Moreover, the environment should be
       freed at the end of the program.

       The function `est_init_net_env' is used in order to initialize the
       networking environment.

       int est_init_net_env(void);
              The return value is true if success, else it is false.  As it is
              allowable to call this function multiple times, it is needed to
              call the function `est_free_net_env' at the same frequency.

       The function `est_free_net_env' is used in order to free the networking
       environment.

       void est_free_net_env(void);
              There is no parameter and no return value.


API FOR NODES
       The type of the structure `ESTNODE' is for abstraction of connection to
       a node.  A node has its own URL.  No entity of `ESTNODE' is accessed
       directly, but it is accessed by the pointer.  The term of node
       connection object means the pointer and its referent.  A node
       connection object is created by the function `est_node_new' and
       destroyed by `est_node_delete'.  Every created node connection object
       should be destroyed.

       The function `est_node_new' is used in order to create a node
       connection object.

       ESTNODE *est_node_new(const char *url);
              `url' specifies the URL of a node.  The return value is a node
              connection object.

       The function `est_node_delete' is used in order to destroy a node
       connection object.

       void est_node_delete(ESTNODE *node);
              `node' specifies a node connection object.

       The function `est_node_set_proxy' is used in order to set the proxy
       information of a node connection object.

       void est_node_set_proxy(ESTNODE *node, const char *host, int port);
              `node' specifies a node connection object.  `host' specifies the
              host name of a proxy server.  `port' specifies the port number
              of the proxy server.

       The function `est_node_set_timeout' is used in order to set timeout of
       a connection.

       void est_node_set_timeout(ESTNODE *node, int sec);
              `node' specifies a node connection object.  `sec' specifies
              timeout of the connection in seconds.

       The function `est_node_set_auth' is used in order to set the
       authentication information of a node connection object.

       void est_node_set_auth(ESTNODE *node, const char *name, const char
       *passwd);
              `node' specifies a node connection object.  `name' specifies the
              name of authentication.  `passwd' specifies the password of the
              authentication.

       The function `est_node_status' is used in order to get the status code
       of the last request of a node.

       int est_node_status(ESTNODE *node);
              `node' specifies a node connection object.  The return value is
              the status code of the last request of the node.  -1 means
              failure of connection.

       The function `est_node_sync' is used in order to synchronize updating
       contents of the database of a node.

       int est_node_sync(ESTNODE *node);
              `node' specifies a node connection object.  The return value is
              true if success, else it is false.

       The function `est_node_optimize' is used in order to optimize the
       database of a node.

       int est_node_optimize(ESTNODE *node);
              `node' specifies a node connection object.  The return value is
              true if success, else it is false.

       The function `est_node_put_doc' is used in order to add a document to a
       node.

       int est_node_put_doc(ESTNODE *node, ESTDOC *doc);
              `node' specifies a node connection object.  `doc' specifies a
              document object.  The document object should have the URI
              attribute.  The return value is true if success, else it is
              false.  If the URI attribute is same with an existing document
              in the node, the existing one is deleted.

       The function `est_node_out_doc' is used in order to remove a document
       from a node.

       int est_node_out_doc(ESTNODE *node, int id);
              `node' specifies a node connection object.  `id' specifies the
              ID number of a registered document.  The return value is true if
              success, else it is false.

       The function `est_node_out_doc_by_uri' is used in order to remove a
       document specified by URI from a node.

       int est_node_out_doc_by_uri(ESTNODE *node, const char *uri);
              `node' specifies a node connection object.  `uri' specifies the
              URI of a registered document.  The return value is true if
              success, else it is false.

       The function `est_node_edit_doc' is used in order to edit attributes of
       a document in a node.

       int est_node_edit_doc(ESTNODE *node, ESTDOC *doc);
              `node' specifies a node connection object.  `doc' specifies a
              document object.  The return value is true if success, else it
              is false.  The ID can not be changed.  If the URI is changed and
              it overlaps the URI of another registered document, this
              function fails.

       The function `est_node_get_doc' is used in order to retrieve a document
       in a node.

       ESTDOC *est_node_get_doc(ESTNODE *node, int id);
              `node' specifies a node connection object.  `id' specifies the
              ID number of a registered document.  The return value is a
              document object.  It should be deleted with `est_doc_delete' if
              it is no longer in use.  On error, `NULL' is returned.

       The function `est_node_get_doc_by_uri' is used in order to retrieve a
       document specified by URI in a node.

       ESTDOC *est_node_get_doc_by_uri(ESTNODE *node, const char *uri);
              `node' specifies a node connection object.  `uri' specifies the
              URI of a registered document.  The return value is a document
              object.  It should be deleted with `est_doc_delete' if it is no
              longer in use.  On error, `NULL' is returned.

       The function `est_node_get_doc_attr' is used in order to retrieve the
       value of an attribute of a document in a node.

       char *est_node_get_doc_attr(ESTNODE *node, int id, const char *name);
              `node' specifies a node connection object.  `id' specifies the
              ID number of a registered document.  `name' specifies the name
              of an attribute.  The return value is the value of the attribute
              or `NULL' if it does not exist.  Because the region of the
              return value is allocated with the `malloc' call, it should be
              released with the `free' call if it is no longer in use.

       The function `est_node_get_doc_attr_by_uri' is used in order to
       retrieve the value of an attribute of a document specified by URI in a
       node.

       char *est_node_get_doc_attr_by_uri(ESTNODE *node, const char *uri,
       const char *name);
              `node' specifies a node connection object.  `uri' specifies the
              URI of a registered document.  `name' specifies the name of an
              attribute.  The return value is the value of the attribute or
              `NULL' if it does not exist.  Because the region of the return
              value is allocated with the `malloc' call, it should be released
              with the `free' call if it is no longer in use.

       The function `est_node_etch_doc' is used in order to extract keywords
       of a document.

       CBMAP *est_node_etch_doc(ESTNODE *node, int id);
              `node' specifies a node connection object.  `id' specifies the
              ID number of a registered document.  The return value is a new
              map object of keywords and their scores in decimal string or
              `NULL' on error.  Because the object of the return value is
              opened with the function `cbmapopen', it should be closed with
              the function `cbmapclose' if it is no longer in use.

       The function `est_node_etch_doc_by_uri' is used in order to extract
       keywords of a document specified by URI in a node.

       CBMAP *est_node_etch_doc_by_uri(ESTNODE *node, const char *uri);
              `node' specifies a node connection object.  `uri' specifies the
              URI of a registered document.  The return value is a new map
              object of keywords and their scores in decimal string or `NULL'
              on error.  Because the object of the return value is opened with
              the function `cbmapopen', it should be closed with the function
              `cbmapclose' if it is no longer in use.

       The function `est_node_uri_to_id' is used in order to get the ID of a
       document specified by URI.

       int est_node_uri_to_id(ESTNODE *node, const char *uri);
              `node' specifies a node connection object.  `uri' specifies the
              URI of a registered document.  The return value is the ID of the
              document.  On error, -1 is returned.

       The function `est_node_name' is used in order to get the name of a
       node.

       const char *est_node_name(ESTNODE *node);
              `node' specifies a node connection object.  The return value is
              the name of the node.  On error, `NULL' is returned.  The life
              duration of the returned string is synchronous with the one of
              the node object.

       The function `est_node_label' is used in order to get the label of a
       node.

       const char *est_node_label(ESTNODE *node);
              `node' specifies a node connection object.  The return value is
              the label of the node.  On error, `NULL' is returned.  The life
              duration of the returned string is synchronous with the one of
              the node object.

       The function `est_node_doc_num' is used in order to get the number of
       documents in a node.

       int est_node_doc_num(ESTNODE *node);
              `node' specifies a node connection object.  The return value is
              the number of documents in the node.  On error, -1 is returned.

       The function `est_node_word_num' is used in order to get the number of
       unique words in a node.

       int est_node_word_num(ESTNODE *node);
              `node' specifies a node connection object.  The return value is
              the number of unique words in the node.  On error, -1 is
              returned.

       The function `est_node_size' is used in order to get the size of the
       database of a node.

       double est_node_size(ESTNODE *node);
              `node' specifies a node connection object.  The return value is
              the size of the database of the node.  On error, -1.0 is
              returned.

       The function `est_node_cache_usage' is used in order to get the usage
       ratio of the cache of a node.

       double est_node_cache_usage(ESTNODE *node);
              `node' specifies a node connection object.  The return value is
              the usage ratio of the cache of the node.  On error, -1.0 is
              returned.

       The function `est_node_admins' is used in order to get a list of names
       of administrators of a node.

       const CBLIST *est_node_admins(ESTNODE *node);
              `node' specifies a node connection object.  The return value is
              a list object of names of administrators.  On error, `NULL' is
              returned.  The life duration of the returned object is
              synchronous with the one of the node object.

       The function `est_node_users' is used in order to get a list of names
       of users of a node.

       const CBLIST *est_node_users(ESTNODE *node);
              `node' specifies a node connection object.  The return value is
              a list object of names of users.  On error, `NULL' is returned.
              The life duration of the returned object is synchronous with the
              one of the node object.

       The function `est_node_links' is used in order to get a list of
       expressions of links of a node.

       const CBLIST *est_node_links(ESTNODE *node);
              `node' specifies a node connection object.  The return value is
              a list object of expressions of links.  Each element is a TSV
              string and has three fields of the URL, the label, and the
              score.  On error, `NULL' is returned.  The life duration of the
              returned object is synchronous with the one of the node object.

       The function `est_node_search' is used in order to search a node for
       documents corresponding a condition.

       ESTNODERES *est_node_search(ESTNODE *node, ESTCOND *cond, int depth);
              `node' specifies a node connection object.  `cond' specifies a
              condition object.  `depth' specifies the depth of meta search.
              The return value is a node result object.  It should be deleted
              with `est_noderes_delete' if it is no longer in use.  On error,
              `NULL' is returned.

       The function `est_node_set_snippet_width' is used in order to set width
       of snippet in the result from a node.

       void est_node_set_snippet_width(ESTNODE *node, int wwidth, int hwidth,
       int awidth);
              `node' specifies a node connection object.  `wwidth' specifies
              whole width of a snippet.  By default, it is 480.  If it is 0,
              no snippet is sent. If it is negative, whole body text is sent
              instead of snippet.  `hwidth' specifies width of strings picked
              up from the beginning of the text.  By default, it is 96.  If it
              is negative 0, the current setting is not changed.  `awidth'
              specifies width of strings picked up around each highlighted
              word. By default, it is 96.  If it is negative, the current
              setting is not changed.

       The function `est_node_set_user' is used in order to manage a user
       account of a node.

       int est_node_set_user(ESTNODE *node, const char *name, int mode);
              `node' specifies a node connection object.  `name' specifies the
              name of a user.  `mode' specifies the operation mode.  0 means
              to delete the account.  1 means to set the account as an
              administrator.  2 means to set the account as a guest.  The
              return value is true if success, else it is false.

       The function `est_node_set_link' is used in order to manage a link of a
       node.

       int est_node_set_link(ESTNODE *node, const char *url, const char
       *label, int credit);
              `node' specifies a node connection object.  `url' specifies the
              URL of the target node of a link.  `label' specifies the label
              of the link.  `credit' specifies the credit of the link.  If it
              is negative, the link is removed.  The return value is true if
              success, else it is false.


API FOR SEARCH RESULTS OF NODES
       The type of the structure `ESTNODERES' is for abstraction of search
       result from a node.  A result is composed of a list of corresponding
       documents and information of hints.  No entity of `ESTNODERES' is
       accessed directly, but it is accessed by the pointer.  The term of node
       result object means the pointer and its referent.  A node result object
       is created by the function `est_node_search' and destroyed by
       `est_noderes_delete'.  Every created node connection object should be
       destroyed.

       The type of the structure `ESTRESDOC' is for abstraction of a document
       in search result.  A result document is composed of some attributes and
       a snippet.  No entity of `ESTRESDOC' is accessed directly, but it is
       accessed by the pointer.  The term of result document object means the
       pointer and its referent.  A result document object is gotten by the
       function `est_noderes_get_doc' but it should not be destroyed because
       the entity is managed inside the node result object.

       The function `est_noderes_delete' is used in order to delete a node
       result object.

       void est_noderes_delete(ESTNODERES *nres);
              `nres' specifies a node result object.

       The function `est_noderes_hints' is used in order to get a map object
       for hints of a node result object.

       CBMAP *est_noderes_hints(ESTNODERES *nres);
              `nres' specifies a node result object.  The return value is a
              map object for hints.  Keys of the map are "VERSION", "NODE",
              "HIT", "HINT#n", "DOCNUM", "WORDNUM", "TIME", "TIME#n",
              "LINK#n", and "VIEW".  The life duration of the returned object
              is synchronous with the one of the node result object.

       The function `est_noderes_eclipse' is used in order to eclipse similar
       documents of a node result object.

       void est_noderes_eclipse(ESTNODERES *nres, int num, double limit);
              `nres' specifies a node result object.  `num' specifies the
              number of documents to be shown.  If it is not more than 0,
              eclipse is undone.  `limit' specifies the lower limit of
              similarity for documents to be eclipsed.  Similarity is between
              0.0 and 1.0.

       The function `est_noderes_doc_num' is used in order to get the number
       of documents in a node result object.

       int est_noderes_doc_num(ESTNODERES *nres);
              `nres' specifies a node result object.  The return value is the
              number of documents in a node result object.

       The function `est_noderes_get_doc' is used in order to refer a result
       document object in a node result object.

       ESTRESDOC *est_noderes_get_doc(ESTNODERES *nres, int index);
              `nres' specifies a node result object.  `index' specifies the
              index of a document.  The return value is a result document
              object or `NULL' if `index' is equal to or more than the number
              of documents.  The life duration of the returned object is
              synchronous with the one of the node result object.

       The function `est_resdoc_uri' is used in order to get the URI of a
       result document object.

       const char *est_resdoc_uri(ESTRESDOC *rdoc);
              `rdoc' specifies a result document object.  The return value is
              the URI of the result document object.  The life duration of the
              returned string is synchronous with the one of the result
              document object.

       The function `est_resdoc_attr_names' is used in order to get a list of
       attribute names of a result document object.

       CBLIST *est_resdoc_attr_names(ESTRESDOC *rdoc);
              `rdoc' specifies a result document object.  The return value is
              a new list object of attribute names of the result document
              object.  Because the object of the return value is opened with
              the function `cblistopen', it should be closed with the function
              `cblistclose' if it is no longer in use.

       The function `est_resdoc_attr' is used in order to get the value of an
       attribute of a result document object.

       const char *est_resdoc_attr(ESTRESDOC *rdoc, const char *name);
              `rdoc' specifies a result document object.  `name' specifies the
              name of an attribute.  The return value is the value of the
              attribute or `NULL' if it does not exist.  The life duration of
              the returned string is synchronous with the one of the result
              document object.

       The function `est_resdoc_snippet' is used in order to get the snippet
       of a result document object.

       const char *est_resdoc_snippet(ESTRESDOC *rdoc);
              `rdoc' specifies a result document object.  The return value is
              a string of the snippet of the result document object.  There
              are tab separated values.  Each line is a string to be shown.
              Though most lines have only one field, some lines have two
              fields.  If the second field exists, the first field is to be
              shown with highlighted, and the second field means its
              normalized form.  The life duration of the returned string is
              synchronous with the one of the result document object.

       The function `est_resdoc_keywords' is used in order to get keywords of
       a result document object.

       const char *est_resdoc_keywords(ESTRESDOC *rdoc);
              `rdoc' specifies a result document object.  The return value is
              a string of serialized keywords of the result document object.
              There are tab separated values.  Keywords and their scores come
              alternately.  The life duration of the returned string is
              synchronous with the one of the result document object.

       The function `est_resdoc_shadows' is used in order to get an array of
       documents eclipsed by a result document object.

       ESTRESDOC **est_resdoc_shadows(ESTRESDOC *rdoc, int *np);
              `rdoc' specifies a result document object.  `np' specifies the
              pointer to a variable to which the number of elements of the
              return value is assigned.  The return value is an array of
              eclipsed result document objects.  The life duration of the
              returned array and its elements is synchronous with the one of
              the result document object.

       The function `est_resdoc_similarity' is used in order to get similarity
       of an eclipsed result document object.

       double est_resdoc_similarity(ESTRESDOC *rdoc);
              `rdoc' specifies a result document object.  The return value is
              similarity of the result document object to the front document
              or -1.0 if it is not eclipsed.


PARALLELING
       Each of node connection objects, node result objects, and result
       document objects can not be shared by threads.  If you use multi
       threads, make each thread have its own objects.  If the precondition is
       kept, functions of the node API can be treated as thread-safe
       functions.


AUTHOR
       Hyper Estraier is written by Mikio Hirabayashi.  You can contact the
       author by e-mail to <mikio@users.sourceforge.net>.  Any suggestion or
       bug report is welcome to the author.


ACKNOWLEDGEMENTS
       Hyper Estraier was developed under management by Fumitoshi Ukai and
       supports by Exploratory Software Project of Information-technology
       Promotion Agency, Japan (IPA).


COPYRIGHT
       Copyright (C) 2004-2007 Mikio Hirabayashi

       Hyper Estraier is free software; you can redistribute it and/or modify
       it under the terms of the GNU Lesser General Public License as
       published by the Free Software Foundation; either version 2 of the
       License, or any later version.

       Hyper Estraier is distributed in the hope that it will be useful, but
       WITHOUT ANY WARRANTY; without even the implied warranty of
       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
       Lesser General Public License for more details.

       You should have received a copy of the GNU Lesser General Public
       License along with Hyper Estraier; if not, write to the Free Software
       Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
       USA.


SEE ALSO
       estconfig(1), estcmd(1), estmaster(1), estcall(1), estwaver(1),
       cabin(3), estraier(3)

       Please see http://hyperestraier.sourceforge.net/nguide-en.html for
       detail.



Man Page                          2007-03-06                        ESTNODE(3)
