Documentation of the functions in the query service

internal/usecases/convertquery/aql.go

@@ -5,58 +5,10 @@ import (
 	"fmt"
 )
 
-// Service is a model for the convertquery use case
-type Service struct {
-}
-
-// NewService creates a new convertquery service
-func NewService() *Service {
-	return &Service{}
-}
-
-// Constraint datatypes
-// text		  MatchTypes: exact/contains/startswith/endswith
-// number   MatchTypes: GT/LT/EQ
-// bool     MatchTypes: EQ/NEQ
-
-// Ranges dus tussen 10 half 5 bijv.
-
-// Struct used for JSON conversion
-type parsedJSON struct {
-	Return    returnStruct     //`json:"return"`
-	Entities  []entityStruct   //`json:"entities"`
-	Relations []relationStruct //`json:"relations"`
-}
-
-type returnStruct struct {
-	Entities  []int //`json:"entities"`
-	Relations []int //`json:"relation"`
-}
-
-type entityStruct struct {
-	Type        string             //`json:"type"`
-	Constraints []constraintStruct //`json:"constraints"`
-}
-type relationStruct struct {
-	Type        string //`json:"type"`
-	EntityFrom  int
-	EntityTo    int
-	Depth       searchDepthStruct
-	Constraints []constraintStruct
-}
-type searchDepthStruct struct {
-	Min int
-	Max int
-}
+/* ConvertQuery converts a json string to an AQL query
+Parameters: jsonMsg is the JSON file directly outputted by the drag and drop query builder in the frontend
 
-type constraintStruct struct {
-	Attribute string //`json:"attribute"`
-	Value     string //`json:"value"`
-	DataType  string //`json:"dataType"`
-	MatchType string //`json:"matchType"`
-}
-
-// ConvertQuery converts a json string to an AQL query
+Return: a string containing the corresponding AQL query and an error */
 func (s *Service) ConvertQuery(jsonMsg *[]byte) (*string, error) {
 
 	jsonStruct, err := convertJSONToStruct(jsonMsg)
@@ -69,7 +21,11 @@ func (s *Service) ConvertQuery(jsonMsg *[]byte) (*string, error) {
 	return result, nil
 }
 
-//convertJSONtoStruct reads a JSON file and sorts the data into the appropriate structs
+/*convertJSONtoStruct reads a JSON file and sorts the data into the appropriate structs
+Parameters: jsonMsg is the JSON file directly outputted by the drag and drop query builder in the frontend
+
+Return: parsedJSON is a struct with the same structure and holding the same data as jsonMsg
+*/
 func convertJSONToStruct(jsonMsg *[]byte) (*parsedJSON, error) {
 	jsonStruct := parsedJSON{}
 	err := json.Unmarshal(*jsonMsg, &jsonStruct)
@@ -81,7 +37,11 @@ func convertJSONToStruct(jsonMsg *[]byte) (*parsedJSON, error) {
 	return &jsonStruct, nil
 }
 
-//createQuery generates a query based on the json file provided
+/* createQuery generates a query based on the json file provided
+Parameters: jsonQuery is a parsedJSON struct holding all the data needed to form a query
+
+Return: a string containing the corresponding AQL query and an error
+*/
 func createQuery(jsonQuery *parsedJSON) *string {
 	// GROTE SIDENOTE:
 	// Vrij zeker dat een query waar alléén edges worden opgevraagd (#4)
@@ -144,6 +104,7 @@ func createQuery(jsonQuery *parsedJSON) *string {
 	}
 
 	// Create UNION statements that create unique lists of all the nodes and relations
+	// Thus removing all duplicates
 	nodeUnion = "\nLET nodes = first(RETURN UNION_DISTINCT("
 	for _, relation := range relationsToReturn {
 		nodeUnion += fmt.Sprintf("flatten(%v[**].vertices), ", relation)
@@ -166,7 +127,12 @@ func createQuery(jsonQuery *parsedJSON) *string {
 	return &ret
 }
 
-//createNodeLet generates a 'LET' statement for a node related query
+/* createNodeLet generates a 'LET' statement for a node related query
+Parameters: node is an entityStruct containing the information of a single node,
+name is the autogenerated name of the node consisting of "n" + the index of the node
+
+Return: a string containing a single LET-statement in AQL
+*/
 func createNodeLet(node *entityStruct, name *string) *string {
 	header := fmt.Sprintf("LET %v = (\n\tFOR x IN %v \n", *name, node.Type)
 	footer := "\tRETURN x\n)\n"
@@ -176,7 +142,13 @@ func createNodeLet(node *entityStruct, name *string) *string {
 	return &ret
 }
 
-//createRelationLetWithFromEntity generates a 'LET' statement for relations with an 'EntityFrom' property
+/* createRelationLetWithFromEntity generates a 'LET' statement for relations with an 'EntityFrom' property and optionally an 'EntitiyTo' property
+Parameters: relation is a relation struct containing the information of a single relation,
+name is the autogenerated name of the node consisting of "r" + the index of the relation,
+entities is a list of entityStructs that are needed to form the relation LET-statement
+
+Return: a string containing a single LET-statement in AQL
+*/
 func createRelationLetWithFromEntity(relation *relationStruct, name string, entities *[]entityStruct) *string {
 	header := fmt.Sprintf("LET %v = (\n\tFOR x IN n%v \n", name, relation.EntityFrom)
 	forStatement := fmt.Sprintf("\tFOR v, e, p IN %v..%v OUTBOUND x %s \n", relation.Depth.Min, relation.Depth.Max, relation.Type)
@@ -204,7 +176,13 @@ func createRelationLetWithFromEntity(relation *relationStruct, name string, enti
 	return &ret
 }
 
-//createRelationLetWithOnlyToEntity generates a 'LET' statement for relations with only an 'EntityTo' property
+/* createRelationLetWithOnlyToEntity generates a 'LET' statement for relations with only an 'EntityTo' property
+Parameters: relation is a relation struct containing the information of a single relation,
+name is the autogenerated name of the node consisting of "r" + the index of the relation,
+entities is a list of entityStructs that are needed to form the relation LET-statement
+
+Return: a string containing a single LET-statement in AQL
+*/
 func createRelationLetWithOnlyToEntity(relation *relationStruct, name string, entities *[]entityStruct) *string {
 	header := fmt.Sprintf("LET %v = (\n\tFOR x IN n%v \n", name, relation.EntityTo)
 	forStatement := fmt.Sprintf("\tFOR v, e, p IN %v..%v INBOUND x %s \n", relation.Depth.Min, relation.Depth.Max, relation.Type)

internal/usecases/convertquery/aqlStructs.go

+package convertquery
+
+// Service is a model for the convertquery use case
+type Service struct {
+}
+
+// NewService creates a new convertquery service
+func NewService() *Service {
+	return &Service{}
+}
+
+// Constraint datatypes
+// text		  MatchTypes: exact/contains/startswith/endswith
+// number   MatchTypes: GT/LT/EQ
+// bool     MatchTypes: EQ/NEQ
+
+// Ranges dus tussen 10 half 5 bijv.
+
+// Struct used for JSON conversion of the incoming byte array
+type parsedJSON struct {
+	Return    returnStruct     //`json:"return"`
+	Entities  []entityStruct   //`json:"entities"`
+	Relations []relationStruct //`json:"relations"`
+}
+
+// returnStruct holds the indices of the entities and relations that need to be returned
+type returnStruct struct {
+	Entities  []int //`json:"entities"`
+	Relations []int //`json:"relation"`
+}
+
+// entityStruct encapsulates a single entity with its corresponding constraints
+type entityStruct struct {
+	Type        string             //`json:"type"`
+	Constraints []constraintStruct //`json:"constraints"`
+}
+
+// relationStruct encapsulates a single relation with its corresponding constraints
+type relationStruct struct {
+	Type        string //`json:"type"`
+	EntityFrom  int
+	EntityTo    int
+	Depth       searchDepthStruct
+	Constraints []constraintStruct
+}
+
+// searchDepthStruct holds the range of traversals for the relation
+type searchDepthStruct struct {
+	Min int
+	Max int
+}
+
+// constraintStruct holds the information of the constraint
+type constraintStruct struct {
+	Attribute string //`json:"attribute"`
+	Value     string //`json:"value"`
+	DataType  string //`json:"dataType"`
+	MatchType string //`json:"matchType"`
+}

internal/usecases/convertquery/createConstraints.go

@@ -2,7 +2,13 @@ package convertquery
 
 import "fmt"
 
-// createConstraintStatements generates the appropriate amount of constraint lines calling createConstraingBoolExpression
+/* createConstraintStatements generates the appropriate amount of constraint lines calling createConstraingBoolExpression
+Parameters: constraints is a list of constraintStructs that specify the constraints of a node or relation,
+name is the id of the corresponding relation/node,
+isRelation is a boolean specifying if this constraint comes from a node or relation
+
+Return: a string containing a FILTER-statement with all the constraints
+*/
 func createConstraintStatements(constraints *[]constraintStruct, name string, isRelation bool) *string {
 	s := ""
 	if len(*constraints) == 0 {
@@ -19,8 +25,15 @@ func createConstraintStatements(constraints *[]constraintStruct, name string, is
 	return &s
 }
 
-// createConstraintBoolExpression generates a bool expression, e.g. {name}.city == "New York".
-// when isRelation is true, {name}.edges[*] ALL == "New York"
+/* createConstraintBoolExpression generates a single boolean expression,
+e.g. {name}.city == "New York".
+
+Parameters: constraint is a single constraint of a node or relation,
+name is the id of the corresponding relation/node,
+isRelation is a boolean specifying if this constraint comes from a node or relation, that changes the structure of the expression
+
+Return: a string containing an boolean expression of a single constraint
+*/
 func createConstraintBoolExpression(constraint *constraintStruct, name string, isRelation bool) *string {
 	var (
 		match string
@@ -28,7 +41,6 @@ func createConstraintBoolExpression(constraint *constraintStruct, name string, i
 		line  string
 	)
 
-	//Wicked switches letsgo
 	switch constraint.DataType {
 	case "text":
 		value = fmt.Sprintf("\"%s\"", constraint.Value)