introducing semantic versions for the Meadow interface

modules/Bio/EnsEMBL/Hive/Meadow.pm

@@ -39,6 +39,37 @@ use warnings;
 use base ('Bio::EnsEMBL::Hive::Configurable');
 
 
+# -------------------------------------- <versioning of the Meadow interface> -------------------------------------------------------
+
+our $MEADOW_MAJOR_VERSION = '1';                # Make sure you change this number whenever an incompatible change is introduced
+
+
+sub get_meadow_major_version {
+
+    return $MEADOW_MAJOR_VERSION;               # fetch the declared $MEADOW_MAJOR_VERSION of the interface
+}
+
+
+sub get_meadow_version {
+    my $self = shift @_;
+
+    return $self->VERSION // 'unversioned';     # fetch the declared $VERSION of a specific Meadow implementation
+}
+
+
+sub check_version_compatibility {
+    my $self = shift @_;
+
+    my $mmv = $self->get_meadow_major_version();
+    my $mv  = $self->get_meadow_version();
+#    warn "$self :  MVC='$mmv', MV='$mv'\n";
+
+    return ($mv=~/^$mmv\./) ? 1 : 0;
+}
+
+# -------------------------------------- </versioning of the Meadow interface> ------------------------------------------------------
+
+
 sub new {
     my ($class, $config) = @_;
 

modules/Bio/EnsEMBL/Hive/Meadow/LOCAL.pm

@@ -37,6 +37,11 @@ use Sys::Hostname;
 use base ('Bio::EnsEMBL::Hive::Meadow');
 
 
+our $VERSION = '1.0';       # Semantic version of the Meadow interface:
+                            #   change the Major version whenever an incompatible change is introduced,
+                            #   change the Minor version whenever the interface is extended, but compatibility is retained.
+
+
 sub name {  # also called to check for availability; for the moment assume LOCAL meadow is always available
 
     return (split(/\./, hostname))[0];     # only take the first name

modules/Bio/EnsEMBL/Hive/Meadow/LSF.pm

@@ -38,6 +38,11 @@ use Bio::EnsEMBL::Hive::Utils ('split_for_bash');
 use base ('Bio::EnsEMBL::Hive::Meadow');
 
 
+our $VERSION = '1.0';       # Semantic version of the Meadow interface:
+                            #   change the Major version whenever an incompatible change is introduced,
+                            #   change the Minor version whenever the interface is extended, but compatibility is retained.
+
+
 sub name {  # also called to check for availability; assume LSF is available if LSF cluster_name can be established
     my $mcni = 'My cluster name is';
     my $cmd = "lsid 2>/dev/null | grep '$mcni'";

modules/Bio/EnsEMBL/Hive/Utils.pm

@@ -55,6 +55,8 @@ package Bio::EnsEMBL::Hive::Utils;
 use strict;
 use warnings;
 use Data::Dumper;
+use Bio::EnsEMBL::Hive::Meadow;
+use Bio::EnsEMBL::Hive::Valley;
 use Bio::EnsEMBL::Hive::Version;
 use Bio::EnsEMBL::Hive::DBSQL::SqlSchemaAdaptor;
 use Bio::EnsEMBL::Hive::DBSQL::DBConnection;
@@ -358,6 +360,22 @@ sub go_figure_dbc {
 sub report_versions {
     print "CodeVersion\t".Bio::EnsEMBL::Hive::Version->get_code_version()."\n";
     print "CompatibleHiveDatabaseSchemaVersion\t".Bio::EnsEMBL::Hive::DBSQL::SqlSchemaAdaptor->get_code_sql_schema_version()."\n";
+
+    print "MeadowInterfaceVersion\t".Bio::EnsEMBL::Hive::Meadow->get_meadow_major_version()."\n";
+    my $meadow_class_path = Bio::EnsEMBL::Hive::Valley->meadow_class_path;
+    foreach my $meadow_class (@{ Bio::EnsEMBL::Hive::Valley->loaded_meadow_drivers }) {
+        $meadow_class=~/^${meadow_class_path}::(.+)$/;
+        my $meadow_driver   = $1;
+        my $meadow_version  = $meadow_class->get_meadow_version;
+        my $compatible      = $meadow_class->check_version_compatibility;
+        my $status          = $compatible
+                                ? ( $meadow_class->name
+                                    ? 'available'
+                                    : 'unavailable'
+                                   )
+                                : 'incompatible';
+        print '',join("\t", 'Meadow::'.$meadow_driver, $meadow_version, $status)."\n";
+    }
 }
 
 1;

modules/Bio/EnsEMBL/Hive/Valley.pm

@@ -49,6 +49,19 @@ sub meadow_class_path {
 }
 
 
+our $_loaded_meadow_drivers;
+
+sub loaded_meadow_drivers {
+
+    unless( $_loaded_meadow_drivers ) {
+        foreach my $meadow_class (@{ $_loaded_meadow_drivers = Bio::EnsEMBL::Hive::Utils::find_submodules( meadow_class_path() ) }) {
+            eval "require $meadow_class";
+        }
+    }
+    return $_loaded_meadow_drivers;
+}
+
+
 sub new {
     my ($class, $config, $default_meadow_type, $pipeline_name) = @_;
 
@@ -59,10 +72,12 @@ sub new {
 
     my $amh = $self->available_meadow_hash( {} );
 
-        # make sure modules are loaded and available ones are checked prior to setting the current one
-    foreach my $meadow_class (@{ find_submodules( $self->meadow_class_path ) }) {
-        eval "require $meadow_class";
-        if($meadow_class->name) {
+        # make sure modules are loaded and available ones are checked prior to setting the current one:
+    foreach my $meadow_class (@{ $self->loaded_meadow_drivers }) {
+
+        if( $meadow_class->check_version_compatibility
+        and $meadow_class->name) {      # the assumption is if we can get a name, it is available
+
             my $meadow_object            = $meadow_class->new( $config );
 
             $meadow_object->pipeline_name( $pipeline_name ) if($pipeline_name);