fix(cgi-bin): add request body parsing to set_membership

cgi-bin/set_membership

@@ -1,6 +1,6 @@
 #!/usr/bin/perl
 #
-# Accepts a HTTP PUT request to set the cluster membership of a node.
+# Accepts a HTTP PUT request to set the cluster membership of a host.
 #
 
 use strict;
@@ -20,8 +20,40 @@ if (($running_directory =~ /^\./) && ($ENV{PWD}))
 
 my $anvil = Anvil::Tools->new();
 
+sub alter_host_membership
+{
+	# Expects the first of positional parameters to be a hash.
+	my $parameters   = shift;
+	my $host_uuid    = $parameters->{host_uuid};
+	my $join_cluster = $parameters->{join_cluster};
+
+	$anvil->Log->variables({
+		source => $THIS_FILE,
+		line   => __LINE__,
+		level  => 2,
+		list   => {
+			host_membership_status => Dumper($anvil->data->{hosts}{host_uuid}{$host_uuid})
+		}
+	});
+}
+
+# Re-adds a host to its anvil cluster.
+#
+# Note: not to be confused wtih adding a new host the an anvil.
+#sub join_cluster
+#{}
+
+# Removes a host from its anvil cluster.
+#
+# Note: does not permanently remove the host; can be re-added.
+#sub leave_cluster
+#{}
+
 $anvil->Get->switches;
 
+# TODO: remove when done; temporarily set log level to 2
+$anvil->Log->level({ set => 2 });
+
 $anvil->Database->connect;
 $anvil->Log->entry({source => $THIS_FILE, line => __LINE__, level => 2, secure => 0, key => "log_0132"});
 if (not $anvil->data->{sys}{database}{connections})
@@ -41,4 +73,49 @@ print $anvil->Template->get({file => "shared.html", name => "json_headers", show
 
 my $response_body = {};
 
+my $request_body;
+
+my $is_decode_json_success = eval {
+	$request_body = decode_json($anvil->data->{cgi}{PUTDATA}{value});
+};
+
+if (not $is_decode_json_success)
+{
+	$anvil->Log->entry({
+		source    => $THIS_FILE,
+		line      => __LINE__,
+		level     => 0,
+		'print'   => 1,
+		priority  => "err",
+		key       => "error_0304",
+		variables => { request_body_string => $anvil->data->{cgi}{PUTDATA}{value}, json_decode_error => $_ }
+	});
+	$anvil->nice_exit({ exit_code => 1 });
+}
+
+my $host_uuid = exists $request_body->{host_uuid} ? $request_body->{host_uuid} : "";
+# Defaults to join; will check whether host is already part of its anvil cluster.
+my $is_member = exists $request_body->{is_member} ? $request_body->{is_member} : 1;
+
+if ($host_uuid)
+{
+	if (exists $anvil->data->{hosts}{host_uuid}{$host_uuid})
+	{
+		alter_host_membership({ host_uuid => $host_uuid, join_cluster => $is_member });
+	}
+	else
+	{
+		$anvil->Log->entry({
+			source    => $THIS_FILE,
+			line      => __LINE__,
+			level     => 0,
+			'print'   => 1,
+			priority  => "err",
+			key       => "error_0160",
+			variables => { name => "host UUID", uuid => $host_uuid }
+		});
+		$anvil->nice_exit({ exit_code => 1 });
+	}
+}
+
 print JSON->new->utf8->encode($response_body)."\n";