psql: Add documentation URL to \help output

Add a link to the specific command's reference web page to the bottom
of its \help output.

Discussion: https://www.postgresql.org/message-id/flat/40179bd0-fa7d-4108-1991-a20ae9ad5667%402ndquadrant.com

diff --git a/src/bin/psql/create_help.pl b/src/bin/psql/create_help.pl
index 96cf3d37ef01ca8b82f6a738a28fe8101b28bcef..d8e6671e6893ee0510584f6dfe42eab25faa120e 100644 (file)
--- a/src/bin/psql/create_help.pl
+++ b/src/bin/psql/create_help.pl
@@ -64,6 +64,7 @@ struct _helpStruct
 {
    const char     *cmd;        /* the command name */
    const char     *help;       /* the help associated with it */
+   const char     *docbook_id; /* DocBook XML id (for generating URL) */
    void (*syntaxfunc)(PQExpBuffer);    /* function that prints the syntax associated with it */
    int             nl_count;   /* number of newlines in syntax (for pager) */
 };
@@ -92,7 +93,7 @@ my %entries;
 
 foreach my $file (sort readdir DIR)
 {
-   my (@cmdnames, $cmddesc, $cmdsynopsis);
+   my ($cmdid, @cmdnames, $cmddesc, $cmdsynopsis);
    $file =~ /\.sgml$/ or next;
 
    open(my $fh, '<', "$docdir/$file") or next;
@@ -104,6 +105,9 @@ foreach my $file (sort readdir DIR)
      m!<refmiscinfo>\s*SQL - Language Statements\s*</refmiscinfo>!i
      or next;
 
+   $filecontent =~ m!<refentry id="([a-z-]+)">!
+     and $cmdid = $1;
+
    # Collect multiple refnames
   LOOP:
    {
@@ -116,7 +120,7 @@ foreach my $file (sort readdir DIR)
    $filecontent =~ m!<synopsis>\s*(.+?)\s*</synopsis>!is
      and $cmdsynopsis = $1;
 
-   if (@cmdnames && $cmddesc && $cmdsynopsis)
+   if (@cmdnames && $cmddesc && $cmdid && $cmdsynopsis)
    {
        s/\"/\\"/g foreach @cmdnames;
 
@@ -144,6 +148,7 @@ foreach my $file (sort readdir DIR)
        foreach my $cmdname (@cmdnames)
        {
            $entries{$cmdname} = {
+               cmdid       => $cmdid,
                cmddesc     => $cmddesc,
                cmdsynopsis => $cmdsynopsis,
                params      => \@params,
@@ -186,6 +191,7 @@ foreach (sort keys %entries)
    $id =~ s/ /_/g;
    print $cfile_handle "    { \"$_\",
       N_(\"$entries{$_}{cmddesc}\"),
+      \"$entries{$_}{cmdid}\",
       sql_help_$id,
       $entries{$_}{nl_count} },
 

diff --git a/src/bin/psql/help.c b/src/bin/psql/help.c
index 6bac9e47fd7c42ba6b720ff1775de90f7dffe999..6fc4ebab1e8205f2f1ecba208f98e55c51ad1fb8 100644 (file)
--- a/src/bin/psql/help.c
+++ b/src/bin/psql/help.c
@@ -623,16 +623,23 @@ helpSQL(const char *topic, unsigned short int pager)
                    strcmp(topic, "*") == 0)
                {
                    PQExpBufferData buffer;
+                   char       *url;
 
                    initPQExpBuffer(&buffer);
                    QL_HELP[i].syntaxfunc(&buffer);
                    help_found = true;
+                   url = psprintf("https://www.postgresql.org/docs/%s/%s.html",
+                                  strstr(PG_VERSION, "devel") ? "devel" : PG_MAJORVERSION,
+                                  QL_HELP[i].docbook_id);
                    fprintf(output, _("Command:     %s\n"
                                      "Description: %s\n"
-                                     "Syntax:\n%s\n\n"),
+                                     "Syntax:\n%s\n\n"
+                                     "URL: %s\n\n"),
                            QL_HELP[i].cmd,
                            _(QL_HELP[i].help),
-                           buffer.data);
+                           buffer.data,
+                           url);
+                   free(url);
                    /* If we have an exact match, exit.  Fixes \h SELECT */
                    if (pg_strcasecmp(topic, QL_HELP[i].cmd) == 0)
                        break;