I suspect this is a bit of a longshot...but...

Has anyone had any dealings with reading a Geo Package .gpkg file using Perl. I cannot find anything in CPAN that might help.

A .gpkg file is a SQLite3 DB file. Of course, Perl can handle this. I have used DBD::SQLite to access the Geo Package. The file I am trying to use only has one layer so it only has one row in the gpkg_contents table. This defines the content I need as being in the openUSRN table.

I've used this code to peek at this table.... 

use DBD::SQLite;
use Data::Dumper;

use strict;
use warnings;

my $dbh = DBI->connect("dbi:SQLite:uri=file:osopenusrn_202203.gpkg?mod
+e=rwc");

my $tab = $dbh->prepare("SELECT * FROM openUSRN");
$tab->execute;
while (my $n = $tab->fetchrow_hashref) {
    print Dumper $n;
}

[download]

There are four fields in the table. Three are human-readable text. However, the one I am most interested in, geometry, is gobbledegook. A quick look at the specification seems to show that it is not going to be trivial to work out how to decode this from scratch. So I am hopeful that someone has trodden this path before to give me a head start or even a solution.

I suspect that the geometry is actually a linestring. I am only interested in getting the co-ordinates of the start and the end of the linestring.

Here is a sample of the output... 

$VAR1 = {
          'geometry' => 'GP ♣4l  ►Îú░ü~▬A ]m&#
+9827;↓⌂▬A└¯╔├☼$→A&#94
+92;╚v■[$→A                ☺Ý♥  ☻ 
+  ☺Û♥  ☻    ]m♣↓⌂▬A└&
+#9562;v■[$→A        ░¡Ï▀¤~▬A└¯&#9
+556;├☼$→A        ☺Û♥  ☻   ►
+Îú░ü~▬A`©▲E+$→A        ░¡Ï▀¤~&#96
+44;A└¯╔├☼$→A        ',
          'usrn' => 2900534,
          'id' => 1497,
          'street_type' => 'Designated Street Name'
        };

[download]

In reply to Geo Package files by Bod

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