Provided by: spamassassin_3.4.2-0ubuntu0.18.04.5_all bug

NAME

       Mail::SpamAssassin::BayesStore::SQL - SQL Bayesian Storage Module Implementation

DESCRIPTION

       This module implementes a SQL based bayesian storage module.

METHODS

   new
       public class (Mail::SpamAssassin::BayesStore::SQL) new (Mail::Spamassassin::Plugin::Bayes
       $bayes)

       Description: This methods creates a new instance of the
       Mail::SpamAssassin::BayesStore::SQL object.  It expects to be passed an instance of the
       Mail::SpamAssassin:Bayes object which is passed into the Mail::SpamAssassin::BayesStore
       parent object.

       This method sets up the database connection and determines the username to use in queries.

   tie_db_readonly
       public instance (Boolean) tie_db_readonly ();

       Description: This method ensures that the database connection is properly setup and
       working.  If necessary it will initialize a user's bayes variables so that they can begin
       using the database immediately.

   tie_db_writable
       public instance (Boolean) tie_db_writable ()

       Description: This method ensures that the database connection is properly setup and
       working. If necessary it will initialize a users bayes variables so that they can begin
       using the database immediately.

   untie_db
       public instance () untie_db ()

       Description: Disconnects from an SQL server.

   calculate_expire_delta
       public instance (%) calculate_expire_delta (Integer $newest_atime,
                                                    Integer $start,
                                                    Integer $max_expire_mult)

       Description: This method performs a calculation on the data to determine the optimum atime
       for token expiration.

   token_expiration
       public instance (Integer, Integer,
                        Integer, Integer) token_expiration(\% $opts,
                                                           Integer $newdelta,
                                                           @ @vars)

       Description: This method performs the database specific expiration of tokens based on the
       passed in $newdelta and @vars.

   sync_due
       public instance (Boolean) sync_due ()

       Description: This method determines if a database sync is currently required.

       Unused for SQL based implementation.

   seen_get
       public instance (String) seen_get (string $msgid)

       Description: This method retrieves the stored value, if any, for $msgid.  The return value
       is the stored string ('s' for spam and 'h' for ham) or undef if $msgid is not found.

   seen_put
       public (Boolean) seen_put (string $msgid, char $flag)

       Description: This method records $msgid as the type given by $flag.  $flag is one of two
       values 's' for spam and 'h' for ham.

   seen_delete
       public instance (Boolean) seen_delete (string $msgid)

       Description: This method removes $msgid from the database.

   get_storage_variables
       public instance (@) get_storage_variables ()

       Description: This method retrieves the various administrative variables used by the Bayes
       process and database.

       The values returned in the array are in the following order:

       0: scan count base

       1: number of spam

       2: number of ham

       3: number of tokens in db

       4: last expire atime

       5: oldest token in db atime

       6: db version value

       7: last journal sync

       8: last atime delta

       9: last expire reduction count

       10: newest token in db atime

   dump_db_toks
       public instance () dump_db_toks (String $template, String $regex, Array @vars)

       Description: This method loops over all tokens, computing the probability for the token
       and then printing it out according to the passed in token.

   set_last_expire
       public instance (Boolean) set_last_expire (Integer $time)

       Description: This method sets the last expire time.

   get_running_expire_tok
       public instance (String $time) get_running_expire_tok ()

       Description: This method determines if an expire is currently running and returns the last
       time set.

       There can be multiple times, so we just pull the greatest (most recent) value.

   set_running_expire_tok
       public instance (String $time) set_running_expire_tok ()

       Description: This method sets the time that an expire starts running.

   remove_running_expire_tok
       public instance (Boolean) remove_running_expire_tok ()

       Description: This method removes the row in the database that indicates that and expire is
       currently running.

   tok_get
       public instance (Integer, Integer, Integer) tok_get (String $token)

       Description: This method retrieves a specificed token ($token) from the database and
       returns it's spam_count, ham_count and last access time.

   tok_get_all
       public instance (\@) tok_get (@ $tokens)

       Description: This method retrieves the specified tokens ($tokens) from storage and returns
       an array ref of arrays spam count, ham acount and last access time.

   tok_count_change
       public instance (Boolean) tok_count_change (Integer $spam_count,
       Integer $ham_count,                              String $token,
       String $atime)

       Description: This method takes a $spam_count and $ham_count and adds it to $tok along with
       updating $toks atime with $atime.

   multi_tok_count_change
       public instance (Boolean) multi_tok_count_change (Integer $spam_count,
                                          Integer $ham_count,
       \% $tokens,                                    String $atime)

       Description: This method takes a $spam_count and $ham_count and adds it to all of the
       tokens in the $tokens hash ref along with updating each token's atime with $atime.

   nspam_nham_get
       public instance ($spam_count, $ham_count) nspam_nham_get ()

       Description: This method retrieves the total number of spam and the total number of ham
       learned.

   nspam_nham_change
       public instance (Boolean) nspam_nham_change (Integer $num_spam,
                                                    Integer $num_ham)

       Description: This method updates the number of spam and the number of ham in the database.

   tok_touch
       public instance (Boolean) tok_touch (String $token,
                                            String $atime)

       Description: This method updates the given tokens ($token) atime.

       The assumption is that the token already exists in the database.

   tok_touch_all
       public instance (Boolean) tok_touch (\@ $tokens
                                            String $atime)

       Description: This method does a mass update of the given list of tokens $tokens, if the
       existing token atime is < $atime.

       The assumption is that the tokens already exist in the database.

       We should never be touching more than N_SIGNIFICANT_TOKENS, so we can make some
       assumptions about how to handle the data (ie no need to batch like we do in tok_get_all)

   cleanup
       public instance (Boolean) cleanup ()

       Description: This method perfoms any cleanup necessary before moving onto the next
       operation.

   get_magic_re
       public instance get_magic_re (String)

       Description: This method returns a regexp which indicates a magic token.

       Unused in SQL implementation.

   sync
       public instance (Boolean) sync (\% $opts)

       Description: This method performs a sync of the database

   perform_upgrade
       public instance (Boolean) perform_upgrade (\% $opts);

       Description: Performs an upgrade of the database from one version to another, not
       currently used in this implementation.

   clear_database
       public instance (Boolean) clear_database ()

       Description: This method deletes all records for a particular user.

       Callers should be aware that any errors returned by this method could cause the database
       to be inconsistent for the given user.

   backup_database
       public instance (Boolean) backup_database ()

       Description: This method will dump the users database in a machine readable format.

   restore_database
       public instance (Boolean) restore_database (String $filename, Boolean $showdots)

       Description: This method restores a database from the given filename, $filename.

       Callers should be aware that any errors returned by this method could causes the database
       to be inconsistent for the given user.

   db_readable
       public instance (Boolean) db_readable()

       Description: This method returns a boolean value indicating if the database is in a
       readable state.

   db_writable
       public instance (Boolean) db_writeable()

       Description: This method returns a boolean value indicating if the database is in a
       writable state.

Private Methods

   _connect_db
       private instance (Boolean) _connect_db ()

       Description: This method connects to the SQL database.

   _get_db_version
       private instance (Integer) _get_db_version ()

       Description: Gets the current version of the database from the special global vars tables.

   _initialize_db
       private instance (Boolean) _initialize_db ()

       Description: This method will check to see if a user has had their bayes variables
       initialized. If not then it will perform this initialization.

   _put_token
       private instance (Boolean) _put_token (string $token,
                                              integer $spam_count,
                                              integer $ham_count,
       string $atime)

       Description: This method performs the work of either inserting or updating a token in the
       database.

   _put_tokens
       private instance (Boolean) _put_tokens (\% $tokens,
                                               integer $spam_count,
                                               integer $ham_count,
       string $atime)

       Description: This method performs the work of either inserting or updating tokens in the
       database.

   _get_oldest_token_age
       private instance (Integer) _get_oldest_token_age ()

       Description: This method finds the atime of the oldest token in the database.

       The use of min(atime) in the SQL is ugly and but really the most efficient way of getting
       the oldest_token_age after we've done a mass expire.  It should only be called at expire
       time.

   _get_num_hapaxes
       private instance (Integer) _get_num_hapaxes ()

       Description: This method gets the total number of hapaxes (spam_count + ham_count == 1) in
       the token database for a user.

   _get_num_lowfreq
       private instance (Integer) _get_num_lowfreq ()

       Description: This method gets the total number of lowfreq tokens (spam_count < 8 and
       ham_count < 8) in the token database for a user

   _token_select_string
       private instance (String) _token_select_string

       Description: This method returns the string to be used in SELECT statements to represent
       the token column.

       The default is to use the RPAD function to pad the token out to 5 characters.