Bug 1985621: trigger uplift changes when hash of last form changes

Author: cgsheeh

extensions/PhabBugz/Extension.pm

@@ -125,6 +125,13 @@ sub db_schema_abstract_schema {
       user_phid     => {TYPE => 'VARCHAR(255)', NOTNULL => 1,},
     ]
   };
+  $args->{'schema'}->{'phab_uplift_form_state'} = {
+    FIELDS => [
+      id               => {TYPE => 'INTSERIAL',    NOTNULL => 1, PRIMARYKEY => 1,},
+      revision_phid    => {TYPE => 'VARCHAR(255)', NOTNULL => 1,},
+      uplift_form_hash => {TYPE => 'VARCHAR(255)', NOTNULL => 1,},
+    ]
+  };
 }
 
 sub install_filesystem {

extensions/PhabBugz/lib/Feed.pm

@@ -354,13 +354,67 @@ sub group_query {
   }
 }
 
-sub _is_uplift_request_form_change {
-  # Return `true` if the story text is an uplift request change.
+sub get_last_uplift_hash {
+  my ($revision_phid) = @_;
+  INFO('Retrieving last uplift form hash for revision ' . $revision_phid);
+
+  return Bugzilla->dbh->selectrow_array(
+    'SELECT uplift_form_hash FROM phab_uplift_form_state WHERE revision_phid = ?',
+    undef,
+    $revision_phid
+  );
+}
+
+sub update_last_uplift_hash {
+  my ($revision_phid, $uplift_hash) = @_;
+  my $dbh = Bugzilla->dbh;
+
+  INFO(
+    'Updating last uplift hash' . $uplift_hash . ' for revision' . $revision_phid
+  );
+
+  $dbh->do(
+    'DELETE FROM phab_uplift_form_state WHERE revision_phid = ?',
+    undef,
+    $revision_phid
+  );
+  $dbh->do(
+    'INSERT INTO phab_uplift_form_state (revision_phid, uplift_form_hash) VALUES (?, ?)',
+    undef,
+    $revision_phid,
+    $uplift_hash
+  );
+}
+
+sub is_uplift_request_form_story_change {
+  # Return `true` if the uplift request form has changed since last check.
   my ($story_text) = @_;
 
   return $story_text =~ /\s+uplift request field/;
 }
 
+sub has_uplift_request_form_changed {
+  # Return `true` if the uplift request form has changed since last check.
+  my ($revision) = @_;
+
+  # Take no action if the form is empty.
+  if (ref $revision->uplift_request ne 'HASH'
+    || !keys %{$revision->uplift_request})
+  {
+    INFO('Uplift request form field empty, ignoring.');
+    return;
+  }
+
+  my $previous_hash = get_last_uplift_hash($revision->phid);
+  if (!$previous_hash) {
+    # If the form is not empty and there is no previous hash,
+    # the form has changed.
+    return 1;
+  }
+
+  return $revision->uplift_hash ne $previous_hash;
+}
+
 sub readable_answer {
   my ($answer) = @_;
 
@@ -414,14 +468,6 @@ sub process_uplift_request_form_change {
   my ($timestamp) = Bugzilla->dbh->selectrow_array('SELECT NOW()');
   my $phab_bot_user = Bugzilla::User->new({name => PHAB_AUTOMATION_USER});
 
-  # Take no action if the form is empty.
-  if (ref $revision->uplift_request ne 'HASH'
-    || !keys %{$revision->uplift_request})
-  {
-    INFO('Uplift request form field cleared, ignoring.');
-    return;
-  }
-
   INFO('Commenting the uplift form on the bug.');
 
   my $comment_content = format_uplift_request_as_markdown(
@@ -515,6 +561,7 @@ sub process_uplift_request_form_change {
   }
 
   INFO("Finished processing uplift request form change for $revision_phid.");
+  update_last_uplift_hash($revision->phid, $revision->uplift_hash);
 }
 
 sub process_revision_change {
@@ -554,9 +601,13 @@ sub process_revision_change {
   my $restore_prev_user = set_phab_user();
   my $bug               = $revision->bug;
 
-  # Change is a submission of the uplift request form.
-  if (_is_uplift_request_form_change($story_text)) {
-    return process_uplift_request_form_change($revision, $bug);
+  # Process uplift request form changes if the hash has changed since phab-bot last
+  # saw it.
+  if (has_uplift_request_form_changed($revision)) {
+    process_uplift_request_form_change($revision, $bug);
+
+    # Return early if updating from a story change.
+    return if is_uplift_request_form_story_change($story_text);
   }
 
   # Check to make sure bug id is valid and author can see it

extensions/PhabBugz/lib/Revision.pm

@@ -10,7 +10,8 @@ package Bugzilla::Extension::PhabBugz::Revision;
 use 5.10.1;
 use Moo;
 
-use Mojo::JSON qw(true);
+use Digest::SHA qw(sha1_hex);
+use Mojo::JSON qw(encode_json true);
 use Scalar::Util qw(blessed weaken);
 use Types::Standard -all;
 use Type::Utils;
@@ -321,6 +322,14 @@ sub secured_title {
   return $self->is_private ? '(secure)' : $self->title;
 }
 
+sub uplift_hash {
+  my ($self) = @_;
+
+  # Mojo's `encode_json` should sort keys by default.
+  my $uplift_json_encoded = encode_json($self->uplift_request);
+  return sha1_hex($uplift_json_encoded);
+}
+
 #########################
 #      Builders         #
 #########################