Begin PIS implementation

dbAccess/pis.go

@@ -0,0 +1,26 @@
+package dbAccess
+
+import (
+	"context"
+	"errors"
+
+	"git.fjla.uk/owlboard/go-types/pkg/database"
+	"go.mongodb.org/mongo-driver/bson"
+	"go.mongodb.org/mongo-driver/mongo"
+)
+
+func GetPisMetadata() (*database.PisMetadata, error) {
+	coll := MongoClient.Database(DatabaseName).Collection(MetaCollection)
+
+	filter := bson.M{"type": "PisMetadata"}
+	var result database.PisMetadata
+	err := coll.FindOne(context.Background(), filter).Decode(&result)
+	if err != nil {
+		if errors.Is(err, mongo.ErrNoDocuments) {
+			return nil, nil
+		}
+		return nil, err
+	}
+
+	return &result, nil
+}