Query chaining done

aql/convertQuery.go

@@ -59,10 +59,11 @@ createQuery generates a query based on the json file provided
 	Return: *string, a string containing the corresponding AQL query and an error
 */
 func createQuery(JSONQuery *entity.IncomingQueryJSON) *string {
-	query := "LET result = {\"vertices\":[],\"edges\":[]}\n"
+	query := ""
 	for list := range listoflists {
 		for index := range listoflists[list] {
 			element := listoflists[list][index]
+			fmt.Println(element.typename)
 			switch element.typename {
 			case "entity":
 				entity := JSONQuery.Entities[element.pointer]
@@ -79,13 +80,26 @@ func createQuery(JSONQuery *entity.IncomingQueryJSON) *string {
 			}
 		}
 	}
+	unusedRelations := findUnusedRelations(JSONQuery)
+	if len(unusedRelations) >= 0 {
+		query += "LET nodes = first(RETURN UNION_DISTINCT("
+		for i := range unusedRelations {
+			query += "flatten(" + unusedRelations[i] + "[**].vertices),"
+		}
+		query += "[],[]))\n"
+		query += "LET edges = first(RETURN UNION_DISTINCT("
+		for i := range unusedRelations {
+			query += "flatten(" + unusedRelations[i] + "[**].edges),"
+		}
+		query += "[],[]))\nRETURN {\"vertices\":nodes, \"edges\":edges }"
+	}
 	return &query
 }
 
 func entityToQuery(element entity.QueryEntityStruct, JSONQuery *entity.IncomingQueryJSON) string {
 	thisname := fmt.Sprintf("e%v", element.ID)
 	ret := createLetFor(thisname, element.Name)
-	ret += "\tRETURN x\n)"
+	ret += "\tRETURN x\n)\n"
 	return ret
 }
 
@@ -114,10 +128,10 @@ func relationToQuery(element entity.QueryRelationStruct, JSONQuery *entity.Incom
 		ret += fmt.Sprintf("\tFOR z in %v%v\n", typeToPrefix(element.ToType), element.ToID)
 	}
 	ret += "\tFILTER x._from == y._id AND x._to == z._id\n"
-	ret += "\tLET nodes = APPEND(result.vertices, [y, z])\n"
+	ret += "\tLET nodes = APPEND([], [y, z])\n"
 	ret += "\tRETURN DISTINCT {\n"
 	ret += "\t\"edges\": x,\n"
-	ret += "\t\"vertices\": nodes\n\t}\n)"
+	ret += "\t\"vertices\": nodes\n\t}\n)\n"
 	return ret
 }
 
@@ -131,7 +145,7 @@ func filterToQuery(element entity.QueryFilterStruct, JSONQuery *entity.IncomingQ
 	thisname := fmt.Sprintf("f%v", element.ID)
 	ret := createLetFor(thisname, fmt.Sprintf("%v%v", typeToPrefix(element.FromType), element.FromID))
 	ret += fmt.Sprintf("\tFILTER x.%v %v %v\n", element.Attribute, wordsToLogicalSign((element.MatchType)), element.Value)
-	ret += "\tRETURN x\n)"
+	ret += "\tRETURN x\n)\n"
 	return ret
 }
 
@@ -196,14 +210,14 @@ func getTupleVar(element entity.QueryGroupByStruct, JSONQuery *entity.IncomingQu
 	result := ""
 	thisname := fmt.Sprintf("gt%v", element.ID)
 	result += createLetFor(thisname, JSONQuery.Relations[element.RelationID].Name)
-	result += createSubVariable("variable_0", "variable_1", fmt.Sprintf("r%v", element.RelationID), "_id", "r._to", element.ByAttribute)
-	result += createSubVariable("variable_2", "variable_3", fmt.Sprintf("%v%v", typeToPrefix(element.GroupType), element.GroupID), "_id", "r._to", element.GroupAttribute)
+	result += createSubVariable("variable_0", "variable_1", fmt.Sprintf("r%v[**].vertices[1]", element.RelationID), "_id", "x._to", "_id")
+	result += createSubVariable("variable_2", "variable_3", fmt.Sprintf("%v%v", typeToPrefix(element.GroupType), element.GroupID), "_id", "x._to", element.GroupAttribute)
 	result += "\tRETURN {\n\t\t\"variable_0\": variable_1, \n\t\t\"variable_1\": variable_3\n\t}\n)\n"
 	return result
 }
 
 func createSubVariable(variableName string, variableName2 string, forName string, filter1 string, filter2 string, returnValue string) string {
-	result := "\tLET " + variableName + " = (\n\tFOR y IN " + forName + "\n"
+	result := "\tLET " + variableName + " = (\n\t\tFOR y IN " + forName + "\n"
 	return result + "\t\tFILTER y." + filter1 + " == " + filter2 + "\n\t\tRETURN y." + returnValue + "\n\t) " +
 		"\n\tLET " + variableName2 + " = " + variableName + "[0] \n"
 }
@@ -220,18 +234,36 @@ func createGroupBy(element entity.QueryGroupByStruct, JSONQuery *entity.Incoming
 		}
 	}
 	if final {
-		result += fmt.Sprintf("\tRETURN {\n\tname: c,\n\t%v: variable_0\n\t}\n)", element.GroupAttribute)
+		result += fmt.Sprintf("\tRETURN {\n\tname: c,\n\t%v: variable_0\n\t}\n)\n", element.GroupAttribute)
 	} else {
-		result += "\tRETURN c\n)"
+		result += "\tRETURN c\n)\n"
 	}
 	return result
 }
 
 func createCollect(element entity.QueryGroupByStruct) string {
-	return "\tCOLLECT c = x.variable_0 INTO groups = x.variable_1\n\t\t" +
+	return "\tCOLLECT c = x.variable_0 INTO groups = x.variable_1\n\t" +
 		"LET variable_0 = " + element.AppliedModifier + "(groups) \n"
 }
 
 func createFilter(filter entity.QueryFilterStruct) string {
 	return "\tFILTER variable_0 " + wordsToLogicalSign(filter.MatchType) + " " + filter.Value + " \n"
 }
+
+func findUnusedRelations(JSONQuery *entity.IncomingQueryJSON) []string {
+	var unused []string
+	for i := range JSONQuery.Relations {
+		relationUnused := true
+		relation := JSONQuery.Relations[i]
+		for j := range JSONQuery.GroupBys {
+			groupBy := JSONQuery.GroupBys[j]
+			if groupBy.RelationID == relation.ID {
+				relationUnused = false
+			}
+		}
+		if relationUnused {
+			unused = append(unused, fmt.Sprintf("r%v", relation.ID))
+		}
+	}
+	return unused
+}