[pve-devel] [PATCH common v4 2/3] add print_text_table, print_entry to CLIHandler

[Stoiko Ivanov]

These two function could serve as a generic output sub for various CLI
utilities
 * print_text_table prints an array of objects in a tabular fashion,
   the formating is passed as an array containg hashes with titles, maximal
   lengths and default values. This way we can stay extensible, by adding other
   keys to the formatting options
 * print_entry prints out a single entry, handling array-refs as properties

Signed-off-by: Stoiko Ivanov <s.ivanov at proxmox.com>
---
 src/PVE/CLIHandler.pm | 59 +++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 59 insertions(+)

diff --git a/src/PVE/CLIHandler.pm b/src/PVE/CLIHandler.pm
index acdeffe..a4f63ee 100644
--- a/src/PVE/CLIHandler.pm
+++ b/src/PVE/CLIHandler.pm
@@ -399,6 +399,65 @@ my $print_bash_completion = sub {
     &$print_result(@option_list);
 };
 
+# prints a formatted table with a title row.
+# $formatopts is an array of hashes, with the following keys:
+# 'key' - the key in the data-objects to use for this column
+# 'title' - the title to print above the column, defaults to 'key' - always gets printed in full
+# 'cutoff' - the maximal length of the data, overlong values will be truncated
+# 'default' - an optional default value for the column
+# the last column always gets printed in full
+sub print_text_table {
+    my ($formatopts, $data) = @_;
+    my ($formatstring, @keys, @titles, %cutoffs, %defaults, $last_col);
+
+    $last_col = $formatopts->[$#{$formatopts}];
+    foreach my $col ( @$formatopts ) {
+	my ($key, $title, $cutoff, $default) = @$col{ qw(key title cutoff default)};
+	$title //= $key;
+
+	push @keys, $key;
+	push @titles, $title;
+	$defaults{$key} = $default;
+
+	#calculate maximal print width and cutoff
+	my $titlelen = length($title);
+
+	my $longest = $titlelen;
+	foreach my $entry (@$data) {
+	    my $len = length($entry->{$key}) // 0;
+	    $longest = $len if $len > $longest;
+	}
+
+	$cutoff = (defined($cutoff) && $cutoff < $longest) ? $cutoff : $longest;
+	$cutoffs{$key} = $cutoff;
+
+	my $printalign = $cutoff > $titlelen ? '-' : '';
+	if ($col == $last_col) {
+	    $formatstring .= "%${printalign}${titlelen}s\n";
+	} else {
+	    $formatstring .= "%${printalign}${cutoff}s ";
+	}
+    }
+
+    printf $formatstring, @titles;
+
+    foreach my $entry (sort { $a->{$keys[0]} cmp $b->{$keys[0]} } @$data){
+        printf $formatstring, map { substr(($entry->{$_} // $defaults{$_}), 0 , $cutoffs{$_}) } @keys;
+    }
+}
+
+sub print_entry {
+    my $entry = shift;
+    #TODO: handle objects/hashes as well
+    foreach my $item (sort keys %$entry) {
+	if (ref($entry->{$item}) eq 'ARRAY'){
+	    printf "%s: [ %s ]\n", $item, join(", ", @{$entry->{$item}});
+	} else {
+	    printf "%s: %s\n", $item, $entry->{$item};
+	}
+    }
+}
+
 sub verify_api {
     my ($class) = @_;
 
-- 
2.11.0