--- /dev/null
+# NewsStats.pm
+#
+# Library functions for the NewsStats package.
+#
+# Copyright (c) 2010-2013 Thomas Hochstein <thh@inter.net>
+#
+# This module can be redistributed and/or modified under the same terms under
+# which Perl itself is published.
+
+package NewsStats;
+
+use strict;
+use warnings;
+our ($VERSION, @ISA, @EXPORT, @EXPORT_OK, %EXPORT_TAGS);
+
+require Exporter;
+@ISA = qw(Exporter);
+@EXPORT = qw(
+ $MyVersion
+ $PackageVersion
+ $FullPath
+ $HomePath
+ ShowVersion
+ ShowPOD
+ ReadConfig
+ OverrideConfig
+ InitDB
+ Bleat
+);
+@EXPORT_OK = qw(
+ GetTimePeriod
+ LastMonth
+ SplitPeriod
+ ListMonth
+ ListNewsgroups
+ ParseHierarchies
+ ReadGroupList
+ OutputData
+ FormatOutput
+ SQLHierarchies
+ SQLSortOrder
+ SQLGroupList
+ SQLSetBounds
+ SQLBuildClause
+ GetMaxLength
+);
+%EXPORT_TAGS = ( TimePeriods => [qw(GetTimePeriod LastMonth SplitPeriod
+ ListMonth)],
+ Output => [qw(OutputData FormatOutput)],
+ SQLHelper => [qw(SQLHierarchies SQLSortOrder SQLGroupList
+ SQLSetBounds SQLBuildClause GetMaxLength)]);
+$VERSION = '0.01';
+our $PackageVersion = '0.01';
+
+use Data::Dumper;
+use File::Basename;
+use Cwd qw(realpath);
+
+use Config::Auto;
+use DBI;
+
+#####-------------------------------- Vars --------------------------------#####
+
+# save $0 in $FullPath
+our $FullPath = $0;
+# strip filename and /bin or /install directory to create the $HomePath
+our $HomePath = dirname(realpath($0));
+$HomePath =~ s/\/(bin|install)//;
+# trim $0
+$0 =~ s%.*/%%;
+# set version string
+our $MyVersion = "$0 $::VERSION (NewsStats.pm $VERSION)";
+
+#####------------------------------- Basics -------------------------------#####
+
+################################################################################
+
+################################################################################
+sub ShowVersion {
+################################################################################
+### display version and exit
+ print "NewsStats v$PackageVersion\n$MyVersion\n";
+ print "Copyright (c) 2010-2012 Thomas Hochstein <thh\@inter.net>\n";
+ print "This program is free software; you may redistribute it ".
+ "and/or modify it under the same terms as Perl itself.\n";
+ exit(100);
+};
+################################################################################
+
+################################################################################
+sub ShowPOD {
+################################################################################
+### feed myself to perldoc and exit
+ exec('perldoc', $FullPath);
+ exit(100);
+};
+################################################################################
+
+################################################################################
+sub ReadConfig {
+################################################################################
+### read config via Config::Auto
+### IN : $ConfFile: config filename
+### OUT: reference to a hash containing the configuration
+ my ($ConfFile) = @_;
+ # set default
+ $ConfFile = $HomePath . '/etc/newsstats.conf' if !$ConfFile;
+ # mandatory configuration options
+ my @Mandatory = ('DBDriver','DBHost','DBUser','DBPw','DBDatabase',
+ 'DBTableRaw','DBTableGrps');
+ # read config via Config::Auto
+ my $ConfR = Config::Auto::parse($ConfFile, format => 'equal');
+ my %Conf = %{$ConfR};
+ # check for mandatory options
+ foreach (@Mandatory) {
+ &Bleat(2,sprintf("Mandatory configuration option %s is not set!",$_))
+ if (!defined($Conf{$_}));
+ }
+ # $Conf{'TLH'} is checked in gatherstats.pl
+ return $ConfR;
+};
+################################################################################
+
+################################################################################
+sub OverrideConfig {
+################################################################################
+### override configuration values
+### IN : $ConfigR : reference to configuration hash
+### $OverrideR: reference to a hash containing overrides
+ my ($ConfigR,$OverrideR) = @_;
+ my %Override = %$OverrideR;
+ # Config hash empty?
+ &Bleat(1,"Empty configuration hash passed to OverrideConfig()")
+ if ( keys %$ConfigR < 1);
+ # return if no overrides
+ return if (keys %Override < 1 or keys %$ConfigR < 1);
+ foreach my $Key (keys %Override) {
+ $$ConfigR{$Key} = $Override{$Key};
+ };
+};
+################################################################################
+
+################################################################################
+sub InitDB {
+################################################################################
+### initialise database connection
+### IN : $ConfigR: reference to configuration hash
+### $Die : if TRUE, die if connection fails
+### OUT: DBHandle
+ my ($ConfigR,$Die) = @_;
+ my %Conf = %$ConfigR;
+ my $DBHandle = DBI->connect(sprintf('DBI:%s:database=%s;host=%s',
+ $Conf{'DBDriver'},$Conf{'DBDatabase'},
+ $Conf{'DBHost'}), $Conf{'DBUser'},
+ $Conf{'DBPw'}, { PrintError => 0 });
+ if (!$DBHandle) {
+ &Bleat(2,$DBI::errstr) if (defined($Die) and $Die);
+ &Bleat(1,$DBI::errstr);
+ };
+ return $DBHandle;
+};
+################################################################################
+
+################################################################################
+sub Bleat {
+################################################################################
+### print warning or error messages and terminate in case of error
+### IN : $Level : 1 = warning, 2 = error
+### $Message: warning or error message
+ my ($Level,$Message) = @_;
+ if ($Level == 1) {
+ warn "$0 W: $Message\n"
+ } elsif ($Level == 2) {
+ die "$0 E: $Message\n"
+ } else {
+ print "$0: $Message\n"
+ }
+};
+################################################################################
+
+#####------------------------------ GetStats ------------------------------#####
+
+################################################################################
+sub ListNewsgroups {
+################################################################################
+### explode a (scalar) list of newsgroup names to a list of newsgroup and
+### hierarchy names where every newsgroup and hierarchy appears only once:
+### de.alt.test,de.alt.admin -> de.ALL, de.alt.ALL, de.alt.test, de.alt.admin
+### IN : $Newsgroups : a list of newsgroups (content of Newsgroups: header)
+### $TLH : top level hierarchy (all other newsgroups are ignored)
+### $ValidGroupsR: reference to a hash containing all valid newsgroups
+### as keys
+### OUT: %Newsgroups : hash containing all newsgroup and hierarchy names as keys
+ my ($Newsgroups,$TLH,$ValidGroupsR) = @_;
+ my %ValidGroups = %{$ValidGroupsR} if $ValidGroupsR;
+ my %Newsgroups;
+ chomp($Newsgroups);
+ # remove whitespace from contents of Newsgroups:
+ $Newsgroups =~ s/\s//;
+ # call &HierarchyCount for each newsgroup in $Newsgroups:
+ for (split /,/, $Newsgroups) {
+ # don't count newsgroup/hierarchy in wrong TLH
+ next if($TLH and !/^$TLH/);
+ # don't count invalid newsgroups
+ if(%ValidGroups and !defined($ValidGroups{$_})) {
+ warn (sprintf("DROPPED: %s\n",$_));
+ next;
+ }
+ # add original newsgroup to %Newsgroups
+ $Newsgroups{$_} = 1;
+ # add all hierarchy elements to %Newsgroups, amended by '.ALL',
+ # i.e. de.alt.ALL and de.ALL
+ foreach (ParseHierarchies($_)) {
+ $Newsgroups{$_.'.ALL'} = 1;
+ }
+ };
+ return %Newsgroups;
+};
+
+################################################################################
+sub ParseHierarchies {
+################################################################################
+### return a list of all hierarchy levels a newsgroup belongs to
+### (for de.alt.test.moderated that would be de/de.alt/de.alt.test)
+### IN : $Newsgroup : a newsgroup name
+### OUT: @Hierarchies: array containing all hierarchies the newsgroup belongs to
+ my ($Newsgroup) = @_;
+ my @Hierarchies;
+ # strip trailing dots
+ $Newsgroup =~ s/(.+)\.+$/$1/;
+ # butcher newsgroup name by "." and add each hierarchy to @Hierarchies
+ # i.e. de.alt.test: "de.alt" and "de"
+ while ($Newsgroup =~ /\./) {
+ $Newsgroup =~ s/^((?:\.?[^.]+)*)\.[^.]+$/$1/;
+ push @Hierarchies, $Newsgroup;
+ };
+ return @Hierarchies;
+};
+
+################################################################################
+sub ReadGroupList {
+################################################################################
+### read a list of valid newsgroups from file (each group on one line,
+### ignoring everything after the first whitespace and so accepting files
+### in checkgroups format as well as (parts of) an INN active file)
+### IN : $Filename : file to read
+### OUT: \%ValidGroups: hash containing all valid newsgroups
+ my ($Filename) = @_;
+ my %ValidGroups;
+ open (my $LIST,"<$Filename") or &Bleat(2,"Cannot read $Filename: $!");
+ while (<$LIST>) {
+ s/^\s*(\S+).*$/$1/;
+ chomp;
+ next if /^$/;
+ $ValidGroups{$_} = '1';
+ };
+ close $LIST;
+ return \%ValidGroups;
+};
+
+################################################################################
+
+#####----------------------------- TimePeriods ----------------------------#####
+
+################################################################################
+sub GetTimePeriod {
+################################################################################
+### get a time period to act on from --month option;
+### if empty, default to last month
+### IN : $Month: may be empty, 'YYYY-MM', 'YYYY-MM:YYYY-MM' or 'all'
+### OUT: $Verbal,$SQL: verbal description and WHERE-clause
+### of the chosen time period
+ my ($Month) = @_;
+ # define result variables
+ my ($Verbal, $SQL);
+ # define a regular expression for a month
+ my $REMonth = '\d{4}-\d{2}';
+
+ # default to last month if option is not set
+ if(!$Month) {
+ $Month = &LastMonth;
+ }
+
+ # check for valid input
+ if ($Month =~ /^$REMonth$/) {
+ # single month (YYYY-MM)
+ ($Month) = &CheckMonth($Month);
+ $Verbal = $Month;
+ $SQL = sprintf("month = '%s'",$Month);
+ } elsif ($Month =~ /^$REMonth:$REMonth$/) {
+ # time period (YYYY-MM:YYYY-MM)
+ $Verbal = sprintf('%s to %s',&SplitPeriod($Month));
+ $SQL = sprintf("month BETWEEN '%s' AND '%s'",&SplitPeriod($Month));
+ } elsif ($Month =~ /^all$/i) {
+ # special case: ALL
+ $Verbal = 'all time';
+ $SQL = '';
+ } else {
+ # invalid input
+ return (undef,undef);
+ }
+
+ return ($Verbal,$SQL);
+};
+
+################################################################################
+sub LastMonth {
+################################################################################
+### get last month from todays date in YYYY-MM format
+### OUT: last month as YYYY-MM
+ # get today's date
+ my (undef,undef,undef,undef,$Month,$Year,undef,undef,undef) = localtime(time);
+ # $Month is already defined from 0 to 11, so no need to decrease it by 1
+ $Year += 1900;
+ if ($Month < 1) {
+ $Month = 12;
+ $Year--;
+ };
+ # return last month
+ return sprintf('%4d-%02d',$Year,$Month);
+};
+
+################################################################################
+sub CheckMonth {
+################################################################################
+### check if input (in YYYY-MM form) is valid with MM between 01 and 12;
+### otherwise, fix it
+### IN : @Month: array of month
+### OUT: @Month: a valid month
+ my (@Month) = @_;
+ foreach my $Month (@Month) {
+ my ($OldMonth) = $Month;
+ my ($CalMonth) = substr ($Month, -2);
+ if ($CalMonth < 1 or $CalMonth > 12) {
+ $CalMonth = '12' if $CalMonth > 12;
+ $CalMonth = '01' if $CalMonth < 1;
+ substr($Month, -2) = $CalMonth;
+ &Bleat(1,sprintf("'%s' is an invalid date (MM must be between '01' ".
+ "and '12'), set to '%s'.",$OldMonth,$Month));
+ }
+ }
+ return @Month;
+};
+
+################################################################################
+sub SplitPeriod {
+################################################################################
+### split a time period denoted by YYYY-MM:YYYY-MM into start and end month
+### IN : $Period: time period
+### OUT: $StartMonth, $EndMonth
+ my ($Period) = @_;
+ my ($StartMonth, $EndMonth) = split /:/, $Period;
+ ($StartMonth,$EndMonth) = CheckMonth($StartMonth,$EndMonth);
+ # switch parameters as necessary
+ if ($EndMonth gt $StartMonth) {
+ return ($StartMonth, $EndMonth);
+ } else {
+ return ($EndMonth, $StartMonth);
+ };
+};
+
+################################################################################
+sub ListMonth {
+################################################################################
+### return a list of months (YYYY-MM) between start and end month
+### IN : $MonthExpression ('YYYY-MM' or 'YYYY-MM to YYYY-MM')
+### OUT: @Months: array containing all months from $MonthExpression enumerated
+ my ($MonthExpression )= @_;
+ # return if single month
+ return ($MonthExpression) if ($MonthExpression =~ /^\d{4}-\d{2}$/);
+ # parse $MonthExpression
+ my ($StartMonth, $EndMonth) = split(' to ',$MonthExpression);
+ # set $Year, $Month from $StartMonth
+ my ($Year, $Month) = split /-/, $StartMonth;
+ # define @Months
+ my (@Months);
+ until ("$Year-$Month" gt $EndMonth) {
+ push @Months, "$Year-$Month";
+ $Month = "$Month"; # force string context
+ $Month++;
+ if ($Month > 12) {
+ $Month = '01';
+ $Year++;
+ };
+ };
+ return @Months;
+};
+
+#####---------------------------- OutputFormats ---------------------------#####
+
+################################################################################
+sub OutputData {
+################################################################################
+### read database query results from DBHandle and print results with formatting
+### IN : $Format : format specifier
+### $Comments : print or suppress all comments for machine-readable output
+### $GroupBy : primary sorting order (month or key)
+### $Precision: number of digits right of decimal point (0 or 2)
+### $ValidKeys: reference to a hash containing all valid keys
+### $FileTempl: file name template (--filetemplate): filetempl-YYYY-MM
+### $DBQuery : database query handle with executed query,
+### containing $Month, $Key, $Value
+### $PadField : padding length for key field (optional) for 'pretty'
+### $PadValue : padding length for value field (optional) for 'pretty'
+ my ($Format, $Comments, $GroupBy, $Precision, $ValidKeys, $FileTempl,
+ $DBQuery, $PadField, $PadValue) = @_;
+ my %ValidKeys = %{$ValidKeys} if $ValidKeys;
+ my ($FileName, $Handle, $OUT);
+ our $LastIteration;
+
+ # define output types
+ my %LegalOutput;
+ @LegalOutput{('dump','list','pretty')} = ();
+ # bail out if format is unknown
+ &Bleat(2,"Unknown output type '$Format'!") if !exists($LegalOutput{$Format});
+
+ while (my ($Month, $Key, $Value) = $DBQuery->fetchrow_array) {
+ # don't display invalid keys
+ if(%ValidKeys and !defined($ValidKeys{$Key})) {
+ # FIXME
+ # &Bleat(1,sprintf("DROPPED: %s",$Key));
+ next;
+ };
+ # care for correct sorting order and abstract from month and keys:
+ # $Caption will be $Month or $Key, according to sorting order,
+ # and $Key will be $Key or $Month, respectively
+ my $Caption;
+ if ($GroupBy eq 'key') {
+ $Caption = $Key;
+ $Key = $Month;
+ } else {
+ $Caption = $Month;
+ }
+ # set output file handle
+ if (!$FileTempl) {
+ $Handle = *STDOUT{IO}; # set $Handle to a reference to STDOUT
+ } elsif (!defined($LastIteration) or $LastIteration ne $Caption) {
+ close $OUT if ($LastIteration);
+ # safeguards for filename creation:
+ # replace potential problem characters with '_'
+ $FileName = sprintf('%s-%s',$FileTempl,$Caption);
+ $FileName =~ s/[^a-zA-Z0-9_-]+/_/g;
+ open ($OUT,">$FileName")
+ or &Bleat(2,sprintf("Cannot open output file '%s': $!",
+ $FileName));
+ $Handle = $OUT;
+ };
+ print $Handle &FormatOutput($Format, $Comments, $Caption, $Key, $Value,
+ $Precision, $PadField, $PadValue);
+ $LastIteration = $Caption;
+ };
+ close $OUT if ($FileTempl);
+};
+
+################################################################################
+sub FormatOutput {
+################################################################################
+### format information for output according to format specifier
+### IN : $Format : format specifier
+### $Comments : print or suppress all comments for machine-readable output
+### $Caption : month (as YYYY-MM) or $Key, according to sorting order
+### $Key : newsgroup, client, ... or $Month, as above
+### $Value : number of postings with that attribute
+### $Precision: number of digits right of decimal point (0 or 2)
+### $PadField : padding length for key field (optional) for 'pretty'
+### $PadValue : padding length for value field (optional) for 'pretty'
+### OUT: $Output: formatted output
+ my ($Format, $Comments, $Caption, $Key, $Value, $Precision, $PadField,
+ $PadValue) = @_;
+ my ($Output);
+ # keep last caption in mind
+ our ($LastIteration);
+ # create one line of output
+ if ($Format eq 'dump') {
+ # output as dump (key value)
+ $Output = sprintf ("# %s:\n",$Caption)
+ if ($Comments and (!defined($LastIteration) or $Caption ne $LastIteration));
+ $Output .= sprintf ("%s %u\n",$Key,$Value);
+ } elsif ($Format eq 'list') {
+ # output as list (caption key value)
+ $Output = sprintf ("%s %s %u\n",$Caption,$Key,$Value);
+ } elsif ($Format eq 'pretty') {
+ # output as a table
+ $Output = sprintf ("# ----- %s:\n",$Caption)
+ if ($Comments and (!defined($LastIteration) or $Caption ne $LastIteration));
+ # increase $PadValue for numbers with decimal point
+ $PadValue += $Precision+1 if $Precision;
+ # add padding if $PadField is set; $PadValue HAS to be set then
+ $Output .= sprintf ($PadField ?
+ sprintf("%%-%us%%s %%%u.*f\n",$PadField,$PadValue) :
+ "%s%s %.*f\n",$Key,$Comments ? ':' : '',
+ $Precision,$Value);
+ };
+ return $Output;
+};
+
+#####------------------------- QueryModifications -------------------------#####
+
+################################################################################
+sub SQLHierarchies {
+################################################################################
+### add exclusion of hierarchy levels (de.alt.ALL) from SQL query by
+### amending the WHERE clause if $ShowHierarchies is false (or don't, if it is
+### true, accordingly)
+### IN : $ShowHierarchies: boolean value
+### OUT: SQL code
+ my ($ShowHierarchies) = @_;
+ return $ShowHierarchies ? '' : "newsgroup NOT LIKE '%.ALL'";
+};
+
+################################################################################
+sub GetMaxLength {
+################################################################################
+### get length of longest fields in future query result
+### IN : $DBHandle : database handle
+### $Table : table to query
+### $Field : field (key!, i.e. month, newsgroup, ...) to check
+### $Value : field (value!, i.e. postings) to check
+### $WhereClause : WHERE clause
+### $HavingClause: HAVING clause
+### @BindVars : bind variables for WHERE clause
+### OUT: $FieldLength : length of longest instance of $Field
+### $ValueLength : length of longest instance of $Value
+ my ($DBHandle,$Table,$Field,$Value,$WhereClause,$HavingClause,@BindVars) = @_;
+ my $DBQuery = $DBHandle->prepare(sprintf("SELECT MAX(LENGTH(%s)),".
+ "MAX(%s) ".
+ "FROM %s %s %s",$Field,,$Value,
+ $Table,$WhereClause,$HavingClause ?
+ 'GROUP BY newsgroup' . $HavingClause .
+ ' ORDER BY LENGTH(newsgroup) '.
+ 'DESC LIMIT 1': ''));
+ $DBQuery->execute(@BindVars) or &Bleat(1,sprintf("Can't get field length ".
+ "for '%s' from table '%s': ".
+ "$DBI::errstr",$Field,$Table));
+ my ($FieldLength,$ValueMax) = $DBQuery->fetchrow_array;
+ my $ValueLength = length($ValueMax) if ($ValueMax);
+ return ($FieldLength,$ValueLength);
+};
+
+################################################################################
+sub SQLSortOrder {
+################################################################################
+### build a SQL 'ORDER BY' clause from $OptGroupBy (primary sorting) and
+### $OptOrderBy (secondary sorting), both ascending or descending;
+### descending sorting order is done by adding '-desc'
+### IN : $GroupBy: primary sort by 'month' (default) or 'newsgroups'
+### $OrderBy: secondary sort by month/newsgroups (default)
+### or number of 'postings'
+### OUT: a SQL ORDER BY clause
+ my ($GroupBy,$OrderBy) = @_;
+ my ($GroupSort,$OrderSort) = ('','');
+ # $GroupBy (primary sorting)
+ if (!$GroupBy) {
+ $GroupBy = 'month';
+ } else {
+ ($GroupBy, $GroupSort) = SQLParseOrder($GroupBy);
+ if ($GroupBy =~ /group/i) {
+ $GroupBy = 'newsgroup';
+ } else {
+ $GroupBy = 'month';
+ }
+ }
+ my $Secondary = ($GroupBy eq 'month') ? 'newsgroup' : 'month';
+ # $OrderBy (secondary sorting)
+ if (!$OrderBy) {
+ $OrderBy = $Secondary;
+ } else {
+ ($OrderBy, $OrderSort) = SQLParseOrder($OrderBy);
+ if ($OrderBy =~ /posting/i) {
+ $OrderBy = "postings $OrderSort, $Secondary";
+ } else {
+ $OrderBy = "$Secondary $OrderSort";
+ }
+ }
+ return ($GroupBy,&SQLBuildClause('order',"$GroupBy $GroupSort",$OrderBy));
+};
+
+################################################################################
+sub SQLParseOrder {
+################################################################################
+### parse $OptGroupBy or $OptOrderBy option of the form param[-desc], e.g.
+### 'month', 'month-desc', 'newsgroups-desc', but also just 'desc'
+### IN : $OrderOption: order option (see above)
+### OUT: parameter to sort by,
+### sort order ('DESC' or nothing, meaning 'ASC')
+ my ($OrderOption) = @_;
+ my $SortOrder = '';
+ if ($OrderOption =~ s/-?desc$//i) {
+ $SortOrder = 'DESC';
+ } else {
+ $OrderOption =~ s/-?asc$//i
+ }
+ return ($OrderOption,$SortOrder);
+};
+
+################################################################################
+sub SQLGroupList {
+################################################################################
+### explode list of newsgroups separated by : (with wildcards)
+### to a SQL 'WHERE' expression
+### IN : $Newsgroups: list of newsgroups (group.one.*:group.two:group.three.*)
+### OUT: SQL code to become part of a 'WHERE' clause,
+### list of newsgroups for SQL bindings
+ my ($Newsgroups) = @_;
+ # substitute '*' wildcard with SQL wildcard character '%'
+ $Newsgroups =~ s/\*/%/g;
+ return (undef,undef) if !CheckValidNewsgroups($Newsgroups);
+ # just one newsgroup?
+ return (SQLGroupWildcard($Newsgroups),$Newsgroups) if $Newsgroups !~ /:/;
+ my ($SQL,@WildcardGroups,@NoWildcardGroups);
+ # list of newsgroups separated by ':'
+ my @GroupList = split /:/, $Newsgroups;
+ foreach (@GroupList) {
+ if ($_ !~ /%/) {
+ # add to list of newsgroup names WITHOUT wildcard
+ push (@NoWildcardGroups,$_);
+ } else {
+ # add to list of newsgroup names WITH wildcard
+ push (@WildcardGroups,$_);
+ # add wildcard to SQL clause
+ # 'OR' if SQL clause is not empty
+ $SQL .= ' OR ' if $SQL;
+ $SQL .= 'newsgroup LIKE ?'
+ }
+ };
+ if (scalar(@NoWildcardGroups)) {
+ # add 'OR' if SQL clause is not empty
+ $SQL .= ' OR ' if $SQL;
+ if (scalar(@NoWildcardGroups) < 2) {
+ # special case: just one newsgroup without wildcard
+ $SQL .= 'newsgroup = ?';
+ } else {
+ # create list of newsgroups to include: 'newsgroup IN (...)'
+ $SQL .= 'newsgroup IN (';
+ my $SQLin;
+ foreach (@NoWildcardGroups) {
+ $SQLin .= ',' if $SQLin;
+ $SQLin .= '?';
+ }
+ # add list to SQL clause
+ $SQL .= $SQLin .= ')';
+ }
+ }
+ # add brackets '()' to SQL clause as needed (more than one wildcard group)
+ if (scalar(@WildcardGroups)) {
+ $SQL = '(' . $SQL .')';
+ }
+ # rebuild @GroupList in (now) correct order
+ @GroupList = (@WildcardGroups,@NoWildcardGroups);
+ return ($SQL,@GroupList);
+};
+
+################################################################################
+sub SQLGroupWildcard {
+################################################################################
+### build a valid SQL 'WHERE' expression with or without wildcards
+### IN : $Newsgroup: newsgroup expression, probably with wildcard
+### (group.name or group.name.%)
+### OUT: SQL code to become part of a 'WHERE' clause
+ my ($Newsgroup) = @_;
+ if ($Newsgroup !~ /%/) {
+ return 'newsgroup = ?';
+ } else {
+ return 'newsgroup LIKE ?';
+ }
+};
+
+################################################################################
+sub SQLSetBounds {
+################################################################################
+### set upper and/or lower boundary (number of postings)
+### IN : $Type: 'level', 'average', 'sum' or 'default'
+### $LowBound,$UppBound: lower/upper boundary, respectively
+### OUT: SQL code to become part of a WHERE or HAVING clause
+ my ($Type,$LowBound,$UppBound) = @_;
+ ($LowBound,$UppBound) = SQLCheckNumber($LowBound,$UppBound);
+ if($LowBound and $UppBound and $LowBound > $UppBound) {
+ &Bleat(1,"Lower boundary $LowBound is larger than Upper boundary ".
+ "$UppBound, exchanging boundaries.");
+ ($LowBound,$UppBound) = ($UppBound,$LowBound);
+ }
+ # default to 'default'
+ my $WhereHavingFunction = 'postings';
+ # set $LowBound to SQL statement:
+ # 'WHERE postings >=', 'HAVING MIN(postings) >=' or 'HAVING AVG(postings) >='
+ if ($Type eq 'level') {
+ $WhereHavingFunction = 'MIN(postings)'
+ } elsif ($Type eq 'average') {
+ $WhereHavingFunction = 'AVG(postings)'
+ } elsif ($Type eq 'sum') {
+ $WhereHavingFunction = 'SUM(postings)'
+ }
+ $LowBound = sprintf('%s >= '.$LowBound,$WhereHavingFunction) if ($LowBound);
+ # set $LowBound to SQL statement:
+ # 'WHERE postings <=', 'HAVING MAX(postings) <=' or 'HAVING AVG(postings) <='
+ if ($Type eq 'level') {
+ $WhereHavingFunction = 'MAX(postings)'
+ } elsif ($Type eq 'average') {
+ $WhereHavingFunction = 'AVG(postings)'
+ } elsif ($Type eq 'sum') {
+ $WhereHavingFunction = 'SUM(postings)'
+ }
+ $UppBound = sprintf('%s <= '.$UppBound,$WhereHavingFunction) if ($UppBound);
+ return ($LowBound,$UppBound);
+};
+
+################################################################################
+sub SQLCheckNumber {
+################################################################################
+### check if input is a valid positive integer; otherwise, make it one
+### IN : @Numbers: array of parameters
+### OUT: @Numbers: a valid positive integer
+ my (@Numbers) = @_;
+ foreach my $Number (@Numbers) {
+ if ($Number and $Number < 0) {
+ &Bleat(1,"Boundary $Number is < 0, set to ".-$Number);
+ $Number = -$Number;
+ }
+ $Number = '' if ($Number and $Number !~ /^\d+$/);
+ }
+ return @Numbers;
+};
+
+################################################################################
+sub SQLBuildClause {
+################################################################################
+### build a valid SQL WHERE, GROUP BY, ORDER BY or HAVING clause
+### from multiple expressions which *may* be empty
+### IN : $Type: 'where', 'having', 'group' or 'order'
+### @Expressions: array of expressions
+### OUT: $SQLClause: a SQL clause
+ my ($Type,@Expressions) = @_;
+ my ($SQLClause,$Separator,$Statement);
+ # set separator ('AND' or ',')
+ if ($Type eq 'where' or $Type eq 'having') {
+ $Separator = 'AND';
+ } else {
+ $Separator = ',';
+ }
+ # set statement
+ if ($Type eq 'where') {
+ $Statement = 'WHERE';
+ } elsif ($Type eq 'order') {
+ $Statement = 'ORDER BY';
+ } elsif ($Type eq 'having') {
+ $Statement = 'HAVING';
+ } else {
+ $Statement = 'GROUP BY';
+ }
+ # build query from expressions with separators
+ foreach my $Expression (@Expressions) {
+ if ($Expression) {
+ $SQLClause .= " $Separator " if ($SQLClause);
+ $SQLClause .= $Expression;
+ }
+ }
+ # add statement in front if not already present
+ $SQLClause = " $Statement " . $SQLClause
+ if ($SQLClause and $SQLClause !~ /$Statement/);
+ return $SQLClause;
+};
+
+#####--------------------------- Verifications ----------------------------#####
+
+################################################################################
+sub CheckValidNewsgroups {
+################################################################################
+### syntax check of newgroup list
+### IN : $Newsgroups: list of newsgroups (group.one.*:group.two:group.three.*)
+### OUT: boolean
+ my ($Newsgroups) = @_;
+ my $InvalidCharRegExp = ',; ';
+ return ($Newsgroups =~ /[$InvalidCharRegExp]/) ? 0 : 1;
+};
+
+
+#####------------------------------- done ---------------------------------#####
+1;
+
+
projects / usenet / newsstats.git / blobdiff