Merge pull request #1 from tedaford/add_postgres_patch

Experiment to add a patch for postgres

lib/faulty/patch/postgres.rb

@@ -0,0 +1,56 @@
+# frozen_string_literal: true
+
+require 'pg'
+
+class Faulty
+  module Patch
+    # Patch for the Postgres gem
+    module Postgres
+      include Base
+
+      Patch.define_circuit_errors(self, ::PG::ConnectionBad)
+
+      QUERY_WHITELIST = [
+        %r{\A(?:/\*.*?\*/)?\s*ROLLBACK}i,
+        %r{\A(?:/\*.*?\*/)?\s*COMMIT}i,
+        %r{\A(?:/\*.*?\*/)?\s*RELEASE\s+SAVEPOINT}i
+      ].freeze
+
+      def initialize(opts = {})
+        @faulty_circuit = Patch.circuit_from_hash(
+          'pg',
+          opts[:faulty],
+          errors: [
+            ::PG::ConnectionBad,
+            ::PG::UnableToSend
+          ],
+          patched_error_mapper: Faulty::Patch::Postgres
+        )
+
+        super
+      end
+
+      def ping
+        faulty_run { super }
+      rescue Faulty::Patch::Postgres::FaultyError
+        false
+      end
+
+      def connect(*args)
+        faulty_run { super }
+      end
+
+      def query(*args)
+        return super if QUERY_WHITELIST.any? { |r| !r.match(args.first).nil? }
+
+        faulty_run { super }
+      end
+    end
+  end
+end
+
+module PG
+  class Connection
+    prepend Faulty::Patch::Postgres
+  end
+end