[Bio] / FigKernelPackages / Tracer.pm Repository:
ViewVC logotype

Diff of /FigKernelPackages/Tracer.pm

Parent Directory Parent Directory | Revision Log Revision Log | View Patch Patch

revision 1.67, Fri Sep 29 15:00:17 2006 UTC revision 1.82, Tue Apr 10 03:51:18 2007 UTC
# Line 19  Line 19 
19    
20      require Exporter;      require Exporter;
21      @ISA = ('Exporter');      @ISA = ('Exporter');
22      @EXPORT = qw(Trace T TSetup QTrace Confess Cluck Min Max Assert Open OpenDir TICK StandardSetup ScriptSetup ScriptFinish Insure ChDir);      @EXPORT = qw(Trace T TSetup QTrace Confess Cluck Min Max Assert Open OpenDir TICK StandardSetup EmergencyKey ETracing ScriptSetup ScriptFinish Insure ChDir Emergency);
23      @EXPORT_OK = qw(GetFile GetOptions Merge MergeOptions ParseCommand ParseRecord UnEscape Escape);      @EXPORT_OK = qw(GetFile GetOptions Merge MergeOptions ParseCommand ParseRecord UnEscape Escape);
24      use strict;      use strict;
25      use Carp qw(longmess croak);      use Carp qw(longmess croak);
# Line 34  Line 34 
34      use LWP::UserAgent;      use LWP::UserAgent;
35      use Time::HiRes 'gettimeofday';      use Time::HiRes 'gettimeofday';
36      use URI::Escape;      use URI::Escape;
37        use Time::Local;
38    
39  =head1 Tracing and Debugging Helpers  =head1 Tracing and Debugging Helpers
40    
41  =head2 Introduction  =head2 Tracing
42    
43  This package provides simple tracing for debugging and reporting purposes. To use it simply call the  This package provides simple tracing for debugging and reporting purposes. To use it simply call the
44  L</TSetup> method to set the options and call L</Trace> to write out trace messages. Each trace  L</TSetup> or L</ETracing> method to set the options and call L</Trace> to write out trace messages.
45  message has a I<trace level> and I<category> associated with it. In addition, the tracing package itself  L</TSetup> and L</ETracing> both establish a I<trace level> and a list of I<categories>. Similarly,
46  has a list of categories and a single trace level set by the B<TSetup> method. Only messages whose trace  each trace message has a I<trace level> and I<category> associated with it. Only messages whose trace
47  level is less than or equal to this package's trace level and whose category is activated will  level is less than or equal to the setup trace level and whose category is activated will
48  be written. Thus, a higher trace level on a message indicates that the message  be written. Thus, a higher trace level on a message indicates that the message
49  is less likely to be seen. A higher trace level passed to B<TSetup> means more trace messages will  is less likely to be seen, while a higher trace level passed to B<TSetup> means more trace messages will
50  appear. To generate a trace message, use the following syntax.  appear.
51    
52  C<< Trace($message) if T(errors => 4); >>  =head3 Putting Trace Messages in Your Code
53    
54    To generate a trace message, use the following syntax.
55    
56        Trace($message) if T(errors => 4);
57    
58  This statement will produce a trace message if the trace level is 4 or more and the C<errors>  This statement will produce a trace message if the trace level is 4 or more and the C<errors>
59  category is active. Note that the special category C<main> is always active, so  category is active. There is a special category C<main> that is always active, so
60    
61  C<< Trace($message) if T(main => 4); >>      Trace($message) if T(main => 4);
62    
63  will trace if the trace level is 4 or more.  will trace if the trace level is 4 or more.
64    
# Line 61  Line 66 
66  following call is made in the B<Sprout> package, it will appear if the C<Sprout> category is  following call is made in the B<Sprout> package, it will appear if the C<Sprout> category is
67  active and the trace level is 2 or more.  active and the trace level is 2 or more.
68    
69  C<< Trace($message) if T(2); >>      Trace($message) if T(2);
70    
71    In scripts, where no package name is available, the category defaults to C<main>.
72    
73    =head3 Custom Tracing
74    
75    Many programs have customized tracing configured using the L</TSetup> method. This is no longer
76    the preferred method, but a knowledge of how custom tracing works can make the more modern
77    L</Emergency Tracing> easier to understand.
78    
79  To set up tracing, you call the L</TSetup> method. The method takes as input a trace level, a list  To set up custom tracing, you call the L</TSetup> method. The method takes as input a trace level,
80  of category names, and a set of options. The trace level and list of category names are  a list of category names, and a destination. The trace level and list of category names are
81  specified as a space-delimited string. Thus  specified as a space-delimited string. Thus
82    
83  C<< TSetup('3 errors Sprout ERDB', 'HTML'); >>      TSetup('3 errors Sprout ERDB', 'TEXT');
84    
85  sets the trace level to 3, activates the C<errors>, C<Sprout>, and C<ERDB> categories, and  sets the trace level to 3, activates the C<errors>, C<Sprout>, and C<ERDB> categories, and
86  specifies that messages should be output as HTML paragraphs.  specifies that messages should be sent to the standard output.
87    
88  To turn on tracing for ALL categories, use an asterisk. The call below sets every category to  To turn on tracing for ALL categories, use an asterisk. The call below sets every category to
89  level 3 and writes the output to the standard error output. This sort of thing might be  level 3 and writes the output to the standard error output. This sort of thing might be
90  useful in a CGI environment.  useful in a CGI environment.
91    
92  C<< TSetup('3 *', 'WARN'); >>      TSetup('3 *', 'WARN');
93    
94  In addition to HTML and file output for trace messages, you can specify that the trace messages  In addition standard error and file output for trace messages, you can specify that the trace messages
95  be queued. The messages can then be retrieved by calling the L</QTrace> method. This approach  be queued. The messages can then be retrieved by calling the L</QTrace> method. This approach
96  is useful if you are building a web page. Instead of having the trace messages interspersed with  is useful if you are building a web page. Instead of having the trace messages interspersed with
97  the page output, they can be gathered together and displayed at the end of the page. This makes  the page output, they can be gathered together and displayed at the end of the page. This makes
98  it easier to debug page formatting problems.  it easier to debug page formatting problems.
99    
100  Finally, you can specify that all trace messages be emitted as warnings.  Finally, you can specify that all trace messages be emitted to a file, or the standard output and
101    a file at the same time. To trace to a file, specify the filename with an output character in front
102    of it.
103    
104        TSetup('4 SQL', ">$fileName");
105    
106    To trace to the standard output and a file at the same time, put a C<+> in front of the angle
107    bracket.
108    
109        TSetup('3 *', "+>$fileName");
110    
111  The flexibility of tracing makes it superior to simple use of directives like C<die> and C<warn>.  The flexibility of tracing makes it superior to simple use of directives like C<die> and C<warn>.
112  Tracer calls can be left in the code with minimal overhead and then turned on only when needed.  Tracer calls can be left in the code with minimal overhead and then turned on only when needed.
113  Thus, debugging information is available and easily retrieved even when the application is  Thus, debugging information is available and easily retrieved even when the application is
114  being used out in the field.  being used out in the field.
115    
116    =head3 Trace Levels
117    
118  There is no hard and fast rule on how to use trace levels. The following is therefore only  There is no hard and fast rule on how to use trace levels. The following is therefore only
119  a suggestion.  a suggestion.
120    
# Line 121  Line 145 
145    
146  =back  =back
147    
148    The format of trace messages is important because some utilities analyze trace files.
149    There are three fields-- the time stamp, the category name, and the text.
150    The time stamp is between square brackets and the category name between angle brackets.
151    After the category name there is a colon (C<:>) followed by the message text.
152    If the square brackets or angle brackets are missing, then the trace management
153    utilities assume that they are encountering a set of pre-formatted lines.
154    
155    Note, however, that this formatting is done automatically by the tracing functions. You
156    only need to know about it if you want to parse a trace file.
157    
158    =head3 Emergency Tracing
159    
160    Sometimes, you need a way for tracing to happen automatically without putting parameters
161    in a form or on the command line. Emergency tracing does this. You invoke emergency tracing
162    from the debug form, which is accessed from I<MySeedInstance>C</FIG/Html/SetPassword.html>.
163    Emergency tracing requires you specify a tracing key. For command-line tools, the key is
164    taken from the C<TRACING> environment variable. For web services, the key is taken from
165    a cookie. Either way, the key tells the tracing facility who you are, so that you control
166    the tracing in your environment without stepping on other users.
167    
168    The key can be anything you want. If you don't have a key, the C<SetPassword> page will
169    generate one for you.
170    
171    You can activate and de-activate emergency tracing from the debugging control panel, as
172    well as display the trace file itself.
173    
174    To enable emergency tracing in your code, call
175    
176        ETracing($cgi)
177    
178    from a web script and
179    
180        ETracing()
181    
182    from a command-line script.
183    
184    The web script will look for the tracing key in the cookies, and the command-line
185    script will look for it in the C<TRACING> environment variable. If you are
186    using the L</StandardScript> or L</StandardSetup> methods, emergency tracing
187    will be configured automatically.
188    
189    =head3 Debugging Control Panel
190    
191    The debugging control panel provides several tools to assist in development of
192    SEED and Sprout software. You access the debugging control panel from the URL
193    C</FIG/Html/SetPassword.html> in whichever seed instance you're using. (So,
194    for example, the panel access point for the development NMPDR system is
195    C<http://web-1.nmpdr.org/next/FIG/Html/SetPassword.html>. Contact Bruce to
196    find out what the password is. From this page, you can also specify a tracing
197    key. If you don't specify a key, one will be generated for you.
198    
199    =head4 Emergency Tracing Form
200    
201    At the bottom of the debugging control panel is a form that allows you to
202    specify a trace level and tracing categories. Special and common categories
203    are listed with check boxes. You can hold your mouse over a check box to see
204    what its category does. In general, however, a category name is the same as
205    the name of the package in which the trace message occurs.
206    
207    Additional categories can be entered in an input box, delimited by spaces or commas.
208    
209    The B<Activate> button turns on Emergency tracing at the level you specify with the
210    specified categories active. The B<Terminate> button turns tracing off. The
211    B<Show File> button displays the current contents of the trace file. The tracing
212    form at the bottom of the control panel is designed for emergency tracing, so it
213    will only affect programs that call L</ETracing>, L</StandardScript>,
214    or L</StandardSetup>.
215    
216    =head4 Script Form
217    
218    The top form of the debugging control panel allows you to enter a tiny script and
219    have the output generated in a formatted table. Certain object variables are
220    predefined in the script, including a FIG object (C<$fig>), a CGI object (C<$cgi>),
221    and-- if Sprout is active-- Sprout (C<$sprout>) and SFXlate (C<$sfx>) objects.
222    
223    The last line of the script must be a scalar, but it can be a reference to a hash,
224    a list, a list of lists, and various other combinations. If you select the appropriate
225    data type in the dropdown box, the output will be formatted accordingly. The form
226    also has controls for specifying tracing. These controls override any emergency
227    tracing in effect.
228    
229    =head4 Database Query Forms
230    
231    The forms between the script form and the emergency tracing form allow you to
232    make queries against the database. The FIG query form allows simple queries against
233    a single FIG table. The Sprout query form uses the B<GetAll> method to do a
234    multi-table query against the Sprout database. B<GetAll> is located in the B<ERDB>
235    package, and it takes five parameters.
236    
237        GetAll(\@objectNames, $filterClause, \@parameters, \@fields, $count);
238    
239    Each of the five parameters corresponds to a text box on the query form:
240    
241    =over 4
242    
243    =item Objects
244    
245    Comma-separated list containing the names of the entity and relationship objects to be retrieved.
246    
247    =item Filter
248    
249    WHERE/ORDER BY clause (without the WHERE) to be used to filter and sort the query. The WHERE clause can
250    be parameterized with parameter markers (C<?>). Each field used must be specified in the standard form
251    B<I<objectName>(I<fieldName>)> or B<$I<number>(I<fieldName>)> where I<fieldName> is the name of a
252    field, I<objectName> is the name of the entity or relationship object containing the field, and
253    I<number> is the 1-based position of the object in the object list. Any parameters
254    specified in the filter clause should be specified in the B<Params> field.
255    The fields in a filter clause can come from primary entity relations,
256    relationship relations, or secondary entity relations; however, all of the
257    entities and relationships involved must be included in the list of object names.
258    
259    =item Params
260    
261    List of the parameters to be substituted in for the parameters marks in the filter clause. This
262    is a comma-separated list without any quoting or escaping.
263    
264    =item fields
265    
266    Comma-separated list of the fields to be returned in each element of the list returned. Fields
267    are specified in the same manner as in the filter clause.
268    
269    =item count
270    
271    Maximum number of records to return. If omitted or 0, all available records will be returned.
272    
273    =back
274    
275    B<GetAll> automatically joins together the entities and relationships listed in the object
276    names. This simplifies the coding of the filter clause, but it means that some queries are
277    not possible, since they cannot be expressed in a linear sequence of joins. This is a limitation
278    that has yet to be addressed.
279    
280  =cut  =cut
281    
282  # Declare the configuration variables.  # Declare the configuration variables.
# Line 200  Line 356 
356          }          }
357          if ($target =~ m/^>[^>]/) {          if ($target =~ m/^>[^>]/) {
358              open TRACEFILE, $target;              open TRACEFILE, $target;
359              print TRACEFILE Now() . " Tracing initialized.\n";              print TRACEFILE "[" . Now() . "] <Tracer>: Tracing initialized.\n";
360              close TRACEFILE;              close TRACEFILE;
361              $Destination = ">$target";              $Destination = ">$target";
362          } else {          } else {
# Line 233  Line 389 
389      ["Sprout", "SproutLoad", "ERDB"]      ["Sprout", "SproutLoad", "ERDB"]
390    
391  This would cause trace messages in the specified three packages to appear in  This would cause trace messages in the specified three packages to appear in
392  the output. There are threer special tracing categories that are automatically  the output. There are two special tracing categories that are automatically
393  handled by this method. In other words, if you used L</TSetup> you would need  handled by this method. In other words, if you used L</TSetup> you would need
394  to include these categories manually, but if you use this method they are turned  to include these categories manually, but if you use this method they are turned
395  on automatically.  on automatically.
396    
397  =over 4  =over 4
398    
 =item FIG  
   
 Turns on trace messages inside the B<FIG> package.  
   
399  =item SQL  =item SQL
400    
401  Traces SQL commands and activity.  Traces SQL commands and activity.
# Line 308  Line 460 
460  In this case, C<register>, C<../xacts>, and C<IDs.tbl> are the positional  In this case, C<register>, C<../xacts>, and C<IDs.tbl> are the positional
461  parameters, and would find themselves in I<@parameters> after executing the  parameters, and would find themselves in I<@parameters> after executing the
462  above code fragment. The tracing would be set to level 2, and the categories  above code fragment. The tracing would be set to level 2, and the categories
463  would be C<FIG>, C<Tracer>, and <DocUtils>. C<FIG> and C<Tracer> are standard,  would be C<Tracer>, and <DocUtils>. C<Tracer> is standard,
464  and C<DocUtils> was included because it came in within the first parameter  and C<DocUtils> was included because it came in within the first parameter
465  to this method. The I<$options> hash would be  to this method. The I<$options> hash would be
466    
# Line 333  Line 485 
485  C<outBruce.log>, and the error output to C<errBruce.log>. This is designed to  C<outBruce.log>, and the error output to C<errBruce.log>. This is designed to
486  simplify starting a command in the background.  simplify starting a command in the background.
487    
488    The user name is also used as the tracing key for L</Emergency Tracing>.
489    Specifying a value of C<E> for the trace level causes emergency tracing to
490    be used instead of custom tracing. If the user name is not specified,
491    the tracing key is taken from the C<Tracing> environment variable. If there
492    is no value for that variable, the tracing key will be computed from the PID.
493    
494  Finally, if the special option C<-h> is specified, the option names will  Finally, if the special option C<-h> is specified, the option names will
495  be traced at level 0 and the program will exit without processing.  be traced at level 0 and the program will exit without processing.
496  This provides a limited help capability. For example, if the user enters  This provides a limited help capability. For example, if the user enters
# Line 342  Line 500 
500  he would see the following output.  he would see the following output.
501    
502      TransactFeatures [options] command transactionDirectory IDfile      TransactFeatures [options] command transactionDirectory IDfile
503          -trace    tracing level (default 2)          -trace    tracing level (default E)
504          -sql      trace SQL commands          -sql      trace SQL commands
505          -safe     use database transactions          -safe     use database transactions
506          -noAlias  do not expect aliases in CHANGE transactions          -noAlias  do not expect aliases in CHANGE transactions
# Line 357  Line 515 
515      { trace => [0, "tracing level (default 0)"],      { trace => [0, "tracing level (default 0)"],
516         ...         ...
517    
518  would set the default trace level to 0 instead of 2, while  would set the default trace level to 0 instead of E, while
519    
520      { trace => ["2-", "tracing level (default 2)"],      { trace => ["2-", "tracing level (default 2)"],
521         ...         ...
522    
523  would leave the default at 2, but trace only to the log file, not to the  would set the default to 2, but trace only to the log file, not to the
524  standard output.  standard output.
525    
526  The parameters to this method are as follows.  The parameters to this method are as follows.
# Line 409  Line 567 
567  sub StandardSetup {  sub StandardSetup {
568      # Get the parameters.      # Get the parameters.
569      my ($categories, $options, $parmHelp, @argv) = @_;      my ($categories, $options, $parmHelp, @argv) = @_;
570        # Get the default tracing key.
571        my $tkey = EmergencyKey();
572      # Add the tracing options.      # Add the tracing options.
573      if (! exists $options->{trace}) {      if (! exists $options->{trace}) {
574          $options->{trace} = [2, "tracing level"];          $options->{trace} = ['E', "tracing level (E for emergency tracing)"];
575      }      }
576      $options->{sql} = [0, "turn on SQL tracing"];      $options->{sql} = [0, "turn on SQL tracing"];
577      $options->{h} = [0, "display command-line options"];      $options->{h} = [0, "display command-line options"];
578      $options->{user} = [$$, "trace log file name suffix"];      $options->{user} = [$tkey, "tracing key"];
579      $options->{background} = [0, "spool standard and error output"];      $options->{background} = [0, "spool standard and error output"];
580      # Create a parsing hash from the options hash. The parsing hash      # Create a parsing hash from the options hash. The parsing hash
581      # contains the default values rather than the default value      # contains the default values rather than the default value
# Line 440  Line 600 
600          open STDOUT, ">$outFileName";          open STDOUT, ">$outFileName";
601          open STDERR, ">$errFileName";          open STDERR, ">$errFileName";
602      }      }
603      # Now we want to set up tracing. First, we need to know if SQL is to      # Now we want to set up tracing. First, we need to know if the user
604      # be traced.      # wants emergency tracing.
605        if ($retOptions->{trace} eq 'E') {
606            ETracing($retOptions->{user});
607        } else {
608            # Here the tracing is controlled from the command line.
609      my @cats = @{$categories};      my @cats = @{$categories};
610      if ($retOptions->{sql}) {      if ($retOptions->{sql}) {
611          push @cats, "SQL";          push @cats, "SQL";
612      }      }
613      # Add the default categories.      # Add the default categories.
614      push @cats, "Tracer", "FIG";          push @cats, "Tracer";
615      # Next, we create the category string by joining the categories.      # Next, we create the category string by joining the categories.
616      my $cats = join(" ", @cats);      my $cats = join(" ", @cats);
617      # Check to determine whether or not the caller wants to turn off tracing      # Check to determine whether or not the caller wants to turn off tracing
# Line 482  Line 646 
646      }      }
647      # Now set up the tracing.      # Now set up the tracing.
648      TSetup("$traceLevel $cats", $traceMode);      TSetup("$traceLevel $cats", $traceMode);
649        }
650      # Check for the "h" option. If it is specified, dump the command-line      # Check for the "h" option. If it is specified, dump the command-line
651      # options and exit the program.      # options and exit the program.
652      if ($retOptions->{h}) {      if ($retOptions->{h}) {
653          $0 =~ m#[/\\](\w+)(\.pl)?$#i;          $0 =~ m#[/\\](\w+)(\.pl)?$#i;
654          Trace("$1 [options] $parmHelp") if T(0);          print "$1 [options] $parmHelp\n";
655          for my $key (sort keys %{$options}) {          for my $key (sort keys %{$options}) {
656              my $name = Pad($key, $longestName, 0, ' ');              my $name = Pad($key, $longestName, 0, ' ');
657              my $desc = $options->{$key}->[1];              my $desc = $options->{$key}->[1];
658              if ($options->{$key}->[0]) {              if ($options->{$key}->[0]) {
659                  $desc .= " (default " . $options->{$key}->[0] . ")";                  $desc .= " (default " . $options->{$key}->[0] . ")";
660              }              }
661              Trace("  $name $desc") if T(0);              print "  $name $desc\n";
662          }          }
663          exit(0);          exit(0);
664      }      }
# Line 767  Line 932 
932      return $value;      return $value;
933  }  }
934    
935    =head3 ParseTraceDate
936    
937    C<< my $time = Tracer::ParseTraceDate($dateString); >>
938    
939    Convert a date from the trace file into a PERL timestamp.
940    
941    =over 4
942    
943    =item dateString
944    
945    The date string from the trace file. The format of the string is determined by the
946    L</Now> method.
947    
948    =item RETURN
949    
950    Returns a PERL time, that is, a number of seconds since the epoch, or C<undef> if
951    the time string is invalid.
952    
953    =back
954    
955    =cut
956    
957    sub ParseTraceDate {
958        # Get the parameters.
959        my ($dateString) = @_;
960        # Declare the return variable.
961        my $retVal;
962        # Parse the date.
963        if ($dateString =~ m#(\d+)/(\d+)/(\d+)\s+(\d+):(\d+):(\d+)#) {
964            # Create a time object. Note we need to convert the day, month,
965            # and year to a different base. Years count from 1900, and
966            # the internal month value is relocated to January = 0.
967            $retVal = timelocal($6, $5, $4, $2, $1 - 1, $3 - 1900);
968        }
969        # Return the result.
970        return $retVal;
971    }
972    
973  =head3 LogErrors  =head3 LogErrors
974    
975  C<< Tracer::LogErrors($fileName); >>  C<< Tracer::LogErrors($fileName); >>
# Line 969  Line 1172 
1172      # Get the timestamp.      # Get the timestamp.
1173      my $timeStamp = Now();      my $timeStamp = Now();
1174      # Format the message. Note we strip off any line terminators at the end.      # Format the message. Note we strip off any line terminators at the end.
1175      my $formatted = "$timeStamp <$LastCategory>: " . Strip($message);      my $formatted = "[$timeStamp] <$LastCategory>: " . Strip($message);
1176      # Process according to the destination.      # Process according to the destination.
1177      if ($Destination eq "TEXT") {      if ($Destination eq "TEXT") {
1178          # Write the message to the standard output.          # Write the message to the standard output.
# Line 1434  Line 1637 
1637      # Close it.      # Close it.
1638      close $handle;      close $handle;
1639      my $actualLines = @retVal;      my $actualLines = @retVal;
1640        Trace("$actualLines lines read from file $fileName.") if T(File => 2);
1641      # Return the file's contents in the desired format.      # Return the file's contents in the desired format.
1642      if (wantarray) {      if (wantarray) {
1643          return @retVal;          return @retVal;
# Line 1469  Line 1673 
1673      my ($fileName, $lines) = @_;      my ($fileName, $lines) = @_;
1674      # Open the output file.      # Open the output file.
1675      my $handle = Open(undef, ">$fileName");      my $handle = Open(undef, ">$fileName");
1676        # Count the lines written.
1677      if (ref $lines ne 'ARRAY') {      if (ref $lines ne 'ARRAY') {
1678          # Here we have a scalar, so we write it raw.          # Here we have a scalar, so we write it raw.
1679          print $handle $lines;          print $handle $lines;
1680            Trace("Scalar put to file $fileName.") if T(File => 3);
1681      } else {      } else {
1682          # Write the lines one at a time.          # Write the lines one at a time.
1683            my $count = 0;
1684          for my $line (@{$lines}) {          for my $line (@{$lines}) {
1685              print $handle "$line\n";              print $handle "$line\n";
1686                $count++;
1687          }          }
1688            Trace("$count lines put to file $fileName.") if T(File => 3);
1689      }      }
1690      # Close the output file.      # Close the output file.
1691      close $handle;      close $handle;
# Line 1720  Line 1929 
1929    
1930  C<< if (Tracer::DebugMode) { ...code... } >>  C<< if (Tracer::DebugMode) { ...code... } >>
1931    
1932  Return TRUE if debug mode has been turned on, else output an error  Return TRUE if debug mode has been turned on, else abort.
 page and return FALSE.  
1933    
1934  Certain CGI scripts are too dangerous to exist in the production  Certain CGI scripts are too dangerous to exist in the production
1935  environment. This method provides a simple way to prevent them  environment. This method provides a simple way to prevent them
1936  from working unless they are explicitly turned on by creating a password  from working unless they are explicitly turned on by creating a password
1937  cookie via the B<SetPassword> script.  If debugging mode  cookie via the B<SetPassword> script.  If debugging mode
1938  is not turned on, an error web page will be output directing the  is not turned on, an error will occur.
 user to enter in the correct password.  
1939    
1940  =cut  =cut
1941    
# Line 1741  Line 1948 
1948      if ($encrypted eq "252dec43280e0c0d6a75ffcec486e61d") {      if ($encrypted eq "252dec43280e0c0d6a75ffcec486e61d") {
1949          $retVal = 1;          $retVal = 1;
1950      } else {      } else {
1951          # Here debug mode is off, so we generate an error page.          # Here debug mode is off, so we generate an error.
1952          my $pageString = PageBuilder::Build("<<Html/ErrorPage.html", {}, "Html");          Confess("Cannot use this facility without logging in.");
         print $pageString;  
1953      }      }
1954      # Return the determination indicator.      # Return the determination indicator.
1955      return $retVal;      return $retVal;
# Line 1895  Line 2101 
2101    
2102  =head3 ScriptSetup  =head3 ScriptSetup
2103    
2104  C<< my ($query, $varHash) = ScriptSetup(); >>  C<< my ($cgi, $varHash) = ScriptSetup($noTrace); >>
2105    
2106  Perform standard tracing and debugging setup for scripts. The value returned is  Perform standard tracing and debugging setup for scripts. The value returned is
2107  the CGI object followed by a pre-built variable hash.  the CGI object followed by a pre-built variable hash. At the end of the script,
2108    the client should call L</ScriptFinish> to output the web page.
2109    
2110    This method calls L</ETracing> to configure tracing, which allows the tracing
2111    to be configured via the emergency tracing form on the debugging control panel.
2112    Tracing will then be turned on automatically for all programs that use the L</ETracing>
2113    method, which includes every program that uses this method or L</StandardSetup>.
2114    
2115    =over 4
2116    
2117    =item noTrace (optional)
2118    
2119    If specified, tracing will be suppressed. This is useful if the script wants to set up
2120    tracing manually.
2121    
2122    =item RETURN
2123    
2124  The C<Trace> query parameter is used to determine whether or not tracing is active and  Returns a two-element list consisting of a CGI query object and a variable hash for
2125  which trace modules (other than C<Tracer> and C<FIG>) should be turned on. Specifying  the output page.
2126  the C<CGI> trace module will trace parameter and environment information. Parameters are  
2127  traced at level 3 and environment variables at level 4. At the end of the script, the  =back
 client should call L</ScriptFinish> to output the web page.  
2128    
2129  =cut  =cut
2130    
2131  sub ScriptSetup {  sub ScriptSetup {
2132        # Get the parameters.
2133        my ($noTrace) = @_;
2134      # Get the CGI query object.      # Get the CGI query object.
2135      my $query = CGI->new();      my $cgi = CGI->new();
2136      # Check for tracing. Set it up if the user asked for it.      # Set up tracing if it's not suppressed.
2137      if ($query->param('Trace')) {      ETracing($cgi) unless $noTrace;
         # Set up tracing.  
         my $ttype = ($query->param('TF') ? ">$FIG_Config::temp/Trace$$.log" : "QUEUE");  
         TSetup($query->param('Trace') . " FIG Tracer", $ttype);  
         # Trace the parameter and environment data.  
         TraceParms($query);  
     } else {  
         # Here tracing is to be turned off. All we allow is errors traced into the  
         # error log.  
         TSetup("0", "WARN");  
     }  
2138      # Create the variable hash.      # Create the variable hash.
2139      my $varHash = { DebugData => '' };      my $varHash = { results => '' };
2140      # Return the query object and variable hash.      # Return the query object and variable hash.
2141      return ($query, $varHash);      return ($cgi, $varHash);
2142    }
2143    
2144    =head3 ETracing
2145    
2146    C<< ETracing($parameter); >>
2147    
2148    Set up emergency tracing. Emergency tracing is tracing that is turned
2149    on automatically for any program that calls this method. The emergency
2150    tracing parameters are stored in a a file identified by a tracing key.
2151    If this method is called with a CGI object, then the tracing key is
2152    taken from a cookie. If it is called with no parameters, then the tracing
2153    key is taken from an environment variable. If it is called with a string,
2154    the tracing key is that string.
2155    
2156    =over 4
2157    
2158    =item parameter
2159    
2160    A parameter from which the tracing key is computed. If it is a scalar,
2161    that scalar is used as the tracing key. If it is a CGI object, the
2162    tracing key is taken from the C<IP> cookie. If it is omitted, the
2163    tracing key is taken from the C<TRACING> environment variable. If it
2164    is a CGI object and emergency tracing is not on, the C<Trace> and
2165    C<TF> parameters will be used to determine the type of tracing.
2166    
2167    =back
2168    
2169    =cut
2170    
2171    sub ETracing {
2172        # Get the parameter.
2173        my ($parameter) = @_;
2174        # Check for CGI mode.
2175        my $cgi = (ref $parameter eq 'CGI' ? $parameter : undef);
2176        # Default to no tracing except errors.
2177        my ($tracing, $dest) = ("0", "WARN");
2178        # Check for emergency tracing.
2179        my $tkey = EmergencyKey($parameter);
2180        my $emergencyFile = EmergencyFileName($tkey);
2181        if (-e $emergencyFile) {
2182            # We have the file. Read in the data.
2183            my @tracing = GetFile($emergencyFile);
2184            # Pull off the time limit.
2185            my $expire = shift @tracing;
2186            # Convert it to seconds.
2187            $expire *= 3600;
2188            # Check the file data.
2189            my $stat = stat($emergencyFile);
2190            my ($now) = gettimeofday;
2191            if ($now - $stat->mtime > $expire) {
2192                # Delete the expired file.
2193                unlink $emergencyFile;
2194            } else {
2195                # Emergency tracing is on. Pull off the destination and
2196                # the trace level;
2197                $dest = shift @tracing;
2198                my $level = shift @tracing;
2199                # Convert the destination to a real tracing destination.
2200                # temp directory.
2201                $dest = EmergencyTracingDest($tkey, $dest);
2202                # Insure Tracer is specified.
2203                my %moduleHash = map { $_ => 1 } @tracing;
2204                $moduleHash{Tracer} = 1;
2205                # Set the trace parameter.
2206                $tracing = join(" ", $level, sort keys %moduleHash);
2207            }
2208        } elsif (defined $cgi) {
2209            # There's no emergency tracing, but we have a CGI object, so check
2210            # for tracing from the form parameters.
2211            if ($cgi->param('Trace')) {
2212                # Here the user has requested tracing via a form.
2213                $dest = ($cgi->param('TF') ? ">$FIG_Config::temp/Trace$$.log" : "QUEUE");
2214                $tracing = $cgi->param('Trace') . " Tracer";
2215            }
2216        }
2217        # Setup the tracing we've determined from all the stuff above.
2218        TSetup($tracing, $dest);
2219        # If we're a web script, trace the parameter and environment data.
2220        if (defined $cgi) {
2221            TraceParms($cgi);
2222        }
2223    }
2224    
2225    =head3 EmergencyFileName
2226    
2227    C<< my $fileName = Tracer::EmergencyFileName($tkey); >>
2228    
2229    Return the emergency tracing file name. This is the file that specifies
2230    the tracing information.
2231    
2232    =over 4
2233    
2234    =item tkey
2235    
2236    Tracing key for the current program.
2237    
2238    =item RETURN
2239    
2240    Returns the name of the file to contain the emergency tracing information.
2241    
2242    =back
2243    
2244    =cut
2245    
2246    sub EmergencyFileName {
2247        # Get the parameters.
2248        my ($tkey) = @_;
2249        # Compute the emergency tracing file name.
2250        return "$FIG_Config::temp/Emergency$tkey.txt";
2251    }
2252    
2253    =head3 EmergencyFileTarget
2254    
2255    C<< my $fileName = Tracer::EmergencyFileTarget($tkey); >>
2256    
2257    Return the emergency tracing target file name. This is the file that receives
2258    the tracing output for file-based tracing.
2259    
2260    =over 4
2261    
2262    =item tkey
2263    
2264    Tracing key for the current program.
2265    
2266    =item RETURN
2267    
2268    Returns the name of the file to contain the trace output.
2269    
2270    =back
2271    
2272    =cut
2273    
2274    sub EmergencyFileTarget {
2275        # Get the parameters.
2276        my ($tkey) = @_;
2277        # Compute the emergency tracing file name.
2278        return "$FIG_Config::temp/trace$tkey.log";
2279    }
2280    
2281    =head3 EmergencyTracingDest
2282    
2283    C<< my $dest = Tracer::EmergencyTracingDest($tkey, $myDest); >>
2284    
2285    This method converts an emergency tracing destination to a real
2286    tracing destination. The main difference is that if the
2287    destination is C<FILE> or C<APPEND>, we convert it to file
2288    output.
2289    
2290    =over 4
2291    
2292    =item tkey
2293    
2294    Tracing key for this environment.
2295    
2296    =item myDest
2297    
2298    Destination from the emergency tracing file.
2299    
2300    =item RETURN
2301    
2302    Returns a destination that can be passed into L</TSetup>.
2303    
2304    =back
2305    
2306    =cut
2307    
2308    sub EmergencyTracingDest {
2309        # Get the parameters.
2310        my ($tkey, $myDest) = @_;
2311        # Declare the return variable.
2312        my $retVal;
2313        # Process according to the destination value.
2314        if ($myDest eq 'FILE') {
2315            $retVal = ">" . EmergencyFileTarget($tkey);
2316        } elsif ($myDest eq 'APPEND') {
2317            $retVal = ">>" . EmergencyFileTarget($tkey);
2318        } else {
2319            $retVal = $myDest;
2320  }  }
2321        # Return the result.
2322        return $retVal;
2323    }
2324    
2325    =head3 Emergency
2326    
2327    C<< Emergency($key, $hours, $dest, $level, @modules); >>
2328    
2329    Turn on emergency tracing. This method can only be invoked over the web and is
2330    should not be called if debug mode is off. The caller specifies the duration of the
2331    emergency in hours, the desired tracing destination, the trace level,
2332    and a list of the trace modules to activate. For the length of the duration, when a
2333    program in an environment with the specified tracing key active invokes a Sprout
2334    CGI script, tracing will be turned on automatically. See L</TSetup> for more
2335    about tracing setup and L</ETracing> for more about emergency tracing.
2336    
2337    =over 4
2338    
2339    =item tkey
2340    
2341    The tracing key. This is used to identify the control file and the trace file.
2342    
2343    =item hours
2344    
2345    Number of hours to keep emergency tracing alive.
2346    
2347    =item dest
2348    
2349    Tracing destination. If no path information is specified for a file
2350    destination, it is put in the FIG temporary directory.
2351    
2352    =item level
2353    
2354    Tracing level. A higher level means more trace messages.
2355    
2356    =item modules
2357    
2358    A list of the tracing modules to activate.
2359    
2360    =back
2361    
2362    =cut
2363    
2364    sub Emergency {
2365        # Get the parameters.
2366        my ($tkey, $hours, $dest, $level, @modules) = @_;
2367        # Create the emergency file.
2368        my $specFile = EmergencyFileName($tkey);
2369        my $outHandle = Open(undef, ">$specFile");
2370        print $outHandle join("\n", $hours, $dest, $level, @modules, "");
2371    }
2372    
2373    =head3 EmergencyKey
2374    
2375    C<< my $tkey = EmergencyKey($parameter); >>
2376    
2377    Return the Key to be used for emergency tracing. This could be an IP address,
2378     a session ID, or a user name, depending on the environment.
2379    
2380    =over 4
2381    
2382    =item parameter
2383    
2384    Parameter defining the method for finding the tracing key. If it is a scalar,
2385    then it is presumed to be the tracing key itself. If it is a CGI object, then
2386    the tracing key is taken from the C<IP> cookie. Otherwise, the tracing key is
2387    taken from the C<TRACING> environment variable.
2388    
2389    =item RETURN
2390    
2391    Returns the key to be used for labels in emergency tracing.
2392    
2393    =back
2394    
2395    =cut
2396    
2397    sub EmergencyKey {
2398        # Get the parameters.
2399        my ($parameter) = @_;
2400        # Declare the return variable.
2401        my $retVal;
2402        # Determine the parameter type.
2403        if (! defined $parameter) {
2404            # Here we're supposed to check the environment.
2405            $retVal = $ENV{TRACING};
2406        } else {
2407            my $ptype = ref $parameter;
2408            if ($ptype eq 'CGI') {
2409                # Here we were invoked from a web page. Look for a cookie.
2410                $retVal = $parameter->cookie('IP');
2411            } elsif (! $ptype) {
2412                # Here the key was passed in.
2413                $retVal = $parameter;
2414            }
2415        }
2416        # If no luck finding a key, use the PID.
2417        if (! defined $retVal) {
2418            $retVal = $$;
2419        }
2420        # Return the result.
2421        return $retVal;
2422    }
2423    
2424    
2425  =head3 TraceParms  =head3 TraceParms
2426    
2427  C<< Tracer::TraceParms($query); >>  C<< Tracer::TraceParms($cgi); >>
2428    
2429  Trace the CGI parameters at trace level CGI => 3 and the environment variables  Trace the CGI parameters at trace level CGI => 3 and the environment variables
2430  at level CGI => 4.  at level CGI => 4.
2431    
2432  =over 4  =over 4
2433    
2434  =item query  =item cgi
2435    
2436  CGI query object containing the parameters to trace.  CGI query object containing the parameters to trace.
2437    
# Line 1948  Line 2441 
2441    
2442  sub TraceParms {  sub TraceParms {
2443      # Get the parameters.      # Get the parameters.
2444      my ($query) = @_;      my ($cgi) = @_;
2445      if (T(CGI => 3)) {      if (T(CGI => 3)) {
2446          # Here we want to trace the parameter data.          # Here we want to trace the parameter data.
2447          my @names = $query->param;          my @names = $cgi->param;
2448          for my $parmName (sort @names) {          for my $parmName (sort @names) {
2449              # Note we skip "Trace", which is for our use only.              # Note we skip the Trace parameters, which are for our use only.
2450              if ($parmName ne 'Trace') {              if ($parmName ne 'Trace' && $parmName ne 'TF') {
2451                  my @values = $query->param($parmName);                  my @values = $cgi->param($parmName);
2452                  Trace("CGI: $parmName = " . join(", ", @values));                  Trace("CGI: $parmName = " . join(", ", @values));
2453              }              }
2454          }          }
         # Now output a GET-style URL for this query.  
         my $getURL = $query->url(-relative => 1, -query => 1);  
         # Strip out the Trace parameters.  
         $getURL =~ s/Trace=\d[^;&]+[;&]//;  
         $getURL =~ s/TF=\d[;&]//;  
         # Output the URL.  
         Trace("URL: ../FIG/$getURL");  
2455          # Display the request method.          # Display the request method.
2456          my $method = $query->request_method();          my $method = $cgi->request_method();
2457          Trace("Method: $method");          Trace("Method: $method");
2458      }      }
2459      if (T(CGI => 4)) {      if (T(CGI => 4)) {
# Line 2002  Line 2488 
2488      use FIG;      use FIG;
2489      # ... more uses ...      # ... more uses ...
2490    
2491      my ($query, $varHash) = ScriptSetup();      my ($cgi, $varHash) = ScriptSetup();
2492      eval {      eval {
2493          # ... get data from $query, put it in $varHash ...          # ... get data from $cgi, put it in $varHash ...
2494      };      };
2495      if ($@) {      if ($@) {
2496          Trace("Script Error: $@") if T(0);          Trace("Script Error: $@") if T(0);
# Line 2052  Line 2538 
2538          $outputString = $webData;          $outputString = $webData;
2539      }      }
2540      # Check for trace messages.      # Check for trace messages.
2541      if ($Destination eq "QUEUE") {      if ($Destination ne "NONE" && $TraceLevel > 0) {
2542          # We have trace messages, so we want to put them at the end of the body. This          # We have trace messages, so we want to put them at the end of the body. This
2543          # is either at the end of the whole string or at the beginning of the BODY          # is either at the end of the whole string or at the beginning of the BODY
2544          # end-tag.          # end-tag.
# Line 2060  Line 2546 
2546          if ($outputString =~ m#</body>#gi) {          if ($outputString =~ m#</body>#gi) {
2547              $pos = (pos $outputString) - 7;              $pos = (pos $outputString) - 7;
2548          }          }
2549          substr $outputString, $pos, 0, QTrace('Html');          # If the trace messages were queued, we unroll them. Otherwise, we display the
2550            # destination.
2551            my $traceHtml;
2552            if ($Destination eq "QUEUE") {
2553                $traceHtml = QTrace('Html');
2554            } elsif ($Destination =~ /^>>(.+)$/) {
2555                # Here the tracing output it to a file. We code it as a hyperlink so the user
2556                # can copy the file name into the clipboard easily.
2557                my $actualDest = $1;
2558                $traceHtml = "<p>Tracing output to $actualDest.</p>\n";
2559            } else {
2560                # Here we have one of the special destinations.
2561                $traceHtml = "<P>Tracing output type is $Destination.</p>\n";
2562            }
2563            substr $outputString, $pos, 0, $traceHtml;
2564      }      }
2565      # Write the output string.      # Write the output string.
2566      print $outputString;      print $outputString;
# Line 2085  Line 2585 
2585  sub Insure {  sub Insure {
2586      my ($dirName) = @_;      my ($dirName) = @_;
2587      if (! -d $dirName) {      if (! -d $dirName) {
2588          Trace("Creating $dirName directory.") if T(2);          Trace("Creating $dirName directory.") if T(File => 2);
2589          eval { mkpath $dirName; };          eval { mkpath $dirName; };
2590          if ($@) {          if ($@) {
2591              Confess("Error creating $dirName: $@");              Confess("Error creating $dirName: $@");
# Line 2114  Line 2614 
2614      if (! -d $dirName) {      if (! -d $dirName) {
2615          Confess("Cannot change to directory $dirName: no such directory.");          Confess("Cannot change to directory $dirName: no such directory.");
2616      } else {      } else {
2617          Trace("Changing to directory $dirName.") if T(4);          Trace("Changing to directory $dirName.") if T(File => 4);
2618          my $okFlag = chdir $dirName;          my $okFlag = chdir $dirName;
2619          if (! $okFlag) {          if (! $okFlag) {
2620              Confess("Error switching to directory $dirName.");              Confess("Error switching to directory $dirName.");
# Line 2293  Line 2793 
2793          my $gid = getgrnam($group);          my $gid = getgrnam($group);
2794          # Get the mask for tracing.          # Get the mask for tracing.
2795          my $traceMask = sprintf("%04o", $mask) . "($mask)";          my $traceMask = sprintf("%04o", $mask) . "($mask)";
2796          Trace("Fixing permissions for directory $dirName using group $group($gid) and mask $traceMask.") if T(2);          Trace("Fixing permissions for directory $dirName using group $group($gid) and mask $traceMask.") if T(File => 2);
2797          my $fixCount = 0;          my $fixCount = 0;
2798          my $lookCount = 0;          my $lookCount = 0;
2799          # @dirs will be a stack of directories to be processed.          # @dirs will be a stack of directories to be processed.
# Line 2308  Line 2808 
2808              if ($dir =~ m!/([^/]+)$!) {              if ($dir =~ m!/([^/]+)$!) {
2809                  $simpleName = $1;                  $simpleName = $1;
2810              }              }
2811              Trace("Simple directory name for $dir is $simpleName.") if T(4);              Trace("Simple directory name for $dir is $simpleName.") if T(File => 4);
2812              # Search for a match.              # Search for a match.
2813              my $match = 0;              my $match = 0;
2814              my $i;              my $i;
# Line 2333  Line 2833 
2833                      Trace("Checking member $thisMem.") if T(4);                      Trace("Checking member $thisMem.") if T(4);
2834                      $lookCount++;                      $lookCount++;
2835                      if ($lookCount % 1000 == 0) {                      if ($lookCount % 1000 == 0) {
2836                          Trace("$lookCount members examined. Current is $thisMem. Mask is $traceMask") if T(3);                          Trace("$lookCount members examined. Current is $thisMem. Mask is $traceMask") if T(File => 3);
2837                      }                      }
2838                      # Fix the group.                      # Fix the group.
2839                      chown -1, $gid, $thisMem;                      chown -1, $gid, $thisMem;
# Line 2360  Line 2860 
2860                  }                  }
2861              }              }
2862          }          }
2863          Trace("$lookCount files and directories processed, $fixCount fixed.") if T(2);          Trace("$lookCount files and directories processed, $fixCount fixed.") if T(File => 2);
2864      };      };
2865      # Check for an error.      # Check for an error.
2866      if ($@) {      if ($@) {
# Line 2463  Line 2963 
2963      my ($handle) = @_;      my ($handle) = @_;
2964      # Declare the return variable.      # Declare the return variable.
2965      my @retVal = ();      my @retVal = ();
2966        Trace("File position is " . tell($handle) . ". EOF flag is " . eof($handle) . ".") if T(File => 4);
2967      # Read from the file.      # Read from the file.
2968      my $line = <$handle>;      my $line = <$handle>;
2969      # Only proceed if we found something.      # Only proceed if we found something.
2970      if (defined $line) {      if (defined $line) {
2971          # Remove the new-line.          # Remove the new-line. We are a bit over-cautious here because the file may be coming in via an
2972          chomp $line;          # upload control and have a nonstandard EOL combination.
2973            $line =~ s/(\r|\n)+$//;
2974            # Here we do some fancy tracing to help in debugging complicated EOL marks.
2975            if (T(File => 4)) {
2976                my $escapedLine = $line;
2977                $escapedLine =~ s/\n/\\n/g;
2978                $escapedLine =~ s/\r/\\r/g;
2979                $escapedLine =~ s/\t/\\t/g;
2980                Trace("Line read: -->$escapedLine<--");
2981            }
2982          # If the line is empty, return a single empty string; otherwise, parse          # If the line is empty, return a single empty string; otherwise, parse
2983          # it into fields.          # it into fields.
2984          if ($line eq "") {          if ($line eq "") {
# Line 2476  Line 2986 
2986          } else {          } else {
2987              push @retVal, split /\t/,$line;              push @retVal, split /\t/,$line;
2988          }          }
2989        } else {
2990            # Trace the reason the read failed.
2991            Trace("End of file: $!") if T(File => 3);
2992      }      }
2993      # Return the result.      # Return the result.
2994      return @retVal;      return @retVal;
# Line 2483  Line 2996 
2996    
2997  =head3 PutLine  =head3 PutLine
2998    
2999  C<< Tracer::PutLine($handle, \@fields); >>  C<< Tracer::PutLine($handle, \@fields, $eol); >>
3000    
3001  Write a line of data to a tab-delimited file. The specified field values will be  Write a line of data to a tab-delimited file. The specified field values will be
3002  output in tab-separated form, with a trailing new-line.  output in tab-separated form, with a trailing new-line.
# Line 2498  Line 3011 
3011    
3012  List of field values.  List of field values.
3013    
3014    =item eol (optional)
3015    
3016    End-of-line character (default is "\n").
3017    
3018  =back  =back
3019    
3020  =cut  =cut
3021    
3022  sub PutLine {  sub PutLine {
3023      # Get the parameters.      # Get the parameters.
3024      my ($handle, $fields) = @_;      my ($handle, $fields, $eol) = @_;
3025      # Write the data.      # Write the data.
3026      print $handle join("\t", @{$fields}) . "\n";      print $handle join("\t", @{$fields}) . ($eol || "\n");
3027  }  }
3028    
3029  =head3 GenerateURL  =head3 GenerateURL
# Line 2521  Line 3038 
3038    
3039  would return  would return
3040    
3041      form.cgi?type=1&string=%22high%20pass%22%20or%20highway      form.cgi?type=1;string=%22high%20pass%22%20or%20highway
3042    
3043  =over 4  =over 4
3044    
# Line 2551  Line 3068 
3068      my @parmList = map { "$_=" . uri_escape($parameters{$_}) } keys %parameters;      my @parmList = map { "$_=" . uri_escape($parameters{$_}) } keys %parameters;
3069      # If the list is nonempty, tack it on.      # If the list is nonempty, tack it on.
3070      if (@parmList) {      if (@parmList) {
3071          $retVal .= "?" . join("&", @parmList);          $retVal .= "?" . join(";", @parmList);
3072        }
3073        # Return the result.
3074        return $retVal;
3075    }
3076    
3077    =head3 ApplyURL
3078    
3079    C<< Tracer::ApplyURL($table, $target, $url); >>
3080    
3081    Run through a two-dimensional table (or more accurately, a list of lists), converting the
3082    I<$target> column to HTML text having a hyperlink to a URL in the I<$url> column. The
3083    URL column will be deleted by this process and the target column will be HTML-escaped.
3084    
3085    This provides a simple way to process the results of a database query into something
3086    displayable by combining a URL with text.
3087    
3088    =over 4
3089    
3090    =item table
3091    
3092    Reference to a list of lists. The elements in the containing list will be updated by
3093    this method.
3094    
3095    =item target
3096    
3097    The index of the column to be converted into HTML.
3098    
3099    =item url
3100    
3101    The index of the column containing the URL. Note that the URL must have a recognizable
3102    C<http:> at the beginning.
3103    
3104    =back
3105    
3106    =cut
3107    
3108    sub ApplyURL {
3109        # Get the parameters.
3110        my ($table, $target, $url) = @_;
3111        # Loop through the table.
3112        for my $row (@{$table}) {
3113            # Apply the URL to the target cell.
3114            $row->[$target] = CombineURL($row->[$target], $row->[$url]);
3115            # Delete the URL from the row.
3116            delete $row->[$url];
3117        }
3118    }
3119    
3120    =head3 CombineURL
3121    
3122    C<< my $combinedHtml = Tracer::CombineURL($text, $url); >>
3123    
3124    This method will convert the specified text into HTML hyperlinked to the specified
3125    URL. The hyperlinking will only take place if the URL looks legitimate: that is, it
3126    is defined and begins with an C<http:> header.
3127    
3128    =over 4
3129    
3130    =item text
3131    
3132    Text to return. This will be HTML-escaped automatically.
3133    
3134    =item url
3135    
3136    A URL to be hyperlinked to the text. If it does not look like a URL, then the text
3137    will be returned without any hyperlinking.
3138    
3139    =item RETURN
3140    
3141    Returns the original text, HTML-escaped, with the URL hyperlinked to it. If the URL
3142    doesn't look right, the HTML-escaped text will be returned without any further
3143    modification.
3144    
3145    =back
3146    
3147    =cut
3148    
3149    sub CombineURL {
3150        # Get the parameters.
3151        my ($text, $url) = @_;
3152        # Declare the return variable.
3153        my $retVal = CGI::escapeHTML($text);
3154        # Verify the URL.
3155        if (defined($url) && $url =~ m!http://!i) {
3156            # It's good, so we apply it to the text.
3157            $retVal = "<a href=\"$url\">$retVal</a>";
3158      }      }
3159      # Return the result.      # Return the result.
3160      return $retVal;      return $retVal;

Legend:
Removed from v.1.67  
changed lines
  Added in v.1.82

MCS Webmaster
ViewVC Help
Powered by ViewVC 1.0.3