libpq: Add "servicefile" connection optionHEADmaster

This commit adds the possibility to specify a service file in a
connection string, using a new option called "servicefile".  The parsing
of the service file happens so as things are done in this order of
priority:
- The servicefile connection option.
- Environment variable PGSERVICEFILE.
- Default path, depending on the HOME environment.

Note that in the last default case, we need to fill in "servicefile" for
the connection's PQconninfoOption to let clients know which service file
has been used for the connection.  Some TAP tests are added, with a few
tweaks required for Windows when using URIs or connection option values,
for the location paths.

Author: Torsten Förtsch <tfoertsch123@gmail.com>
Co-authored-by: Ryo Kanbayashi <kanbayashi.dev@gmail.com>
Discussion: https://postgr.es/m/CAKkG4_nCjx3a_F3gyXHSPWxD8Sd8URaM89wey7fG_9g7KBkOCQ@mail.gmail.com

1 files changed, 77 insertions, 2 deletions

diff --git a/src/interfaces/libpq/t/006_service.pl b/src/interfaces/libpq/t/006_service.pl
index d896558a6cc..797e6232b8f 100644
--- a/src/interfaces/libpq/t/006_service.pl
+++ b/src/interfaces/libpq/t/006_service.pl
@@ -53,6 +53,13 @@ copy($srvfile_valid, $srvfile_nested)
   or die "Could not copy $srvfile_valid to $srvfile_nested: $!";
 append_to_file($srvfile_nested, 'service=invalid_srv' . $newline);
 
+# Service file with nested "servicefile" defined.
+my $srvfile_nested_2 = "$td/pg_service_nested_2.conf";
+copy($srvfile_valid, $srvfile_nested_2)
+  or die "Could not copy $srvfile_valid to $srvfile_nested_2: $!";
+append_to_file($srvfile_nested_2,
+	'servicefile=' . $srvfile_default . $newline);
+
 # Set the fallback directory lookup of the service file to the temporary
 # directory of this test.  PGSYSCONFDIR is used if the service file
 # defined in PGSERVICEFILE cannot be found, or when a service file is
@@ -158,9 +165,77 @@ local $ENV{PGSERVICEFILE} = "$srvfile_empty";
 
 	$dummy_node->connect_fails(
 		'service=my_srv',
-		'connection with nested service file',
+		'connection with "service" in nested service file',
+		expected_stderr =>
+		  qr/nested "service" specifications not supported in service file/);
+
+	local $ENV{PGSERVICEFILE} = $srvfile_nested_2;
+
+	$dummy_node->connect_fails(
+		'service=my_srv',
+		'connection with "servicefile" in nested service file',
 		expected_stderr =>
-		  qr/nested service specifications not supported in service file/);
+		  qr/nested "servicefile" specifications not supported in service file/
+	);
+}
+
+# Properly escape backslashes in the path, to ensure the generation of
+# correct connection strings.
+my $srvfile_win_cared = $srvfile_valid;
+$srvfile_win_cared =~ s/\\/\\\\/g;
+
+# Checks that the "servicefile" option works as expected
+{
+	$dummy_node->connect_ok(
+		q{service=my_srv servicefile='} . $srvfile_win_cared . q{'},
+		'connection with valid servicefile in connection string',
+		sql => "SELECT 'connect3_1'",
+		expected_stdout => qr/connect3_1/);
+
+	# Encode slashes and backslash
+	my $encoded_srvfile = $srvfile_valid =~ s{([\\/])}{
+		$1 eq '/' ? '%2F' : '%5C'
+	}ger;
+
+	# Additionally encode a colon in servicefile path of Windows
+	$encoded_srvfile =~ s/:/%3A/g;
+
+	$dummy_node->connect_ok(
+		'postgresql:///?service=my_srv&servicefile=' . $encoded_srvfile,
+		'connection with valid servicefile in URI',
+		sql => "SELECT 'connect3_2'",
+		expected_stdout => qr/connect3_2/);
+
+	local $ENV{PGSERVICE} = 'my_srv';
+	$dummy_node->connect_ok(
+		q{servicefile='} . $srvfile_win_cared . q{'},
+		'connection with PGSERVICE and servicefile in connection string',
+		sql => "SELECT 'connect3_3'",
+		expected_stdout => qr/connect3_3/);
+
+	$dummy_node->connect_ok(
+		'postgresql://?servicefile=' . $encoded_srvfile,
+		'connection with PGSERVICE and servicefile in URI',
+		sql => "SELECT 'connect3_4'",
+		expected_stdout => qr/connect3_4/);
+}
+
+# Check that the "servicefile" option takes priority over the PGSERVICEFILE
+# environment variable.
+{
+	local $ENV{PGSERVICEFILE} = 'non-existent-file.conf';
+
+	$dummy_node->connect_fails(
+		'service=my_srv',
+		'connection with invalid PGSERVICEFILE',
+		expected_stderr =>
+		  qr/service file "non-existent-file\.conf" not found/);
+
+	$dummy_node->connect_ok(
+		q{service=my_srv servicefile='} . $srvfile_win_cared . q{'},
+		'connection with both servicefile and PGSERVICEFILE',
+		sql => "SELECT 'connect4_1'",
+		expected_stdout => qr/connect4_1/);
 }
 
 $node->teardown_node;