POC: implement complexity calculation of engine [TT-10595]

[kofoworola]

Description

POC to show the implementation of the complexity calculation algorithm in the engine

Related Issue

Motivation and Context

How This Has Been Tested

Screenshots (if appropriate)

Types of changes

• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)
• [ ] Refactoring or add test (improvements in base code or adds test coverage to functionality)

Checklist

• [ ] I ensured that the documentation is up to date
• [ ] I explained why this PR updates go.mod in detail with reasoning why it's required
• [ ] I would like a code coverage CI quality gate exception and have explained why

[github-actions[bot]]

API Changes

--- prev.txt	2024-01-18 09:11:12.829427376 +0000
+++ current.txt	2024-01-18 09:11:09.741409760 +0000
@@ -805,7 +805,46 @@
                     "required": [
                         "enabled"
                     ]
-                }
+                },
+				 "complexity": {
+          			"type": ["object","null"],
+          			"properties": {
+            			"enabled": {
+              				"type": "boolean"
+            			},
+            			"max_nodes": {
+              				"type": "integer"
+						},
+						"max_depth": {
+							"type": "integer"
+						},
+						"max_complexity": {
+							"type": "integer"
+						},
+						"fields": {
+              				"type": ["array","null"],
+              				"required": ["type_name", "field_name"],
+							"properties": {
+				                "type_name": {
+									"type": "string"
+				                },
+                				"field_name": {
+									"type": "string"
+				                },
+                				"max_nodes": {
+									"type": "integer"
+				                },
+                				"max_depth": {
+				                  "type": "integer"
+                				},
+				                "max_complexity": {
+									"type": "integer"
+				                }
+							}
+			            }
+          			},
+          			"required": ["enabled"]
+				}
             },
             "required": [
                 "enabled"
@@ -1189,9 +1228,6 @@
 	PersistGraphQL          []PersistGraphQLMeta  `bson:"persist_graphql" json:"persist_graphql"`
 }
 
-func (e *ExtendedPathsSet) Clear()
-    Clear omits values that have OAS API definition conversions in place.
-
 type ExternalOAuth struct {
 	Enabled   bool       `bson:"enabled" json:"enabled"`
 	Providers []Provider `bson:"providers" json:"providers"`
@@ -1215,6 +1251,14 @@
 	SymbolName string `bson:"func_name" json:"func_name"`
 }
 
+type GraphQLComplexityConfig struct {
+	Enabled       bool                           `bson:"enabled" json:"enabled"`
+	MaxNodes      int                            `bson:"max_nodes" json:"max_nodes"`
+	MaxDepth      int                            `bson:"max_depth" json:"max_depth"`
+	MaxComplexity int                            `bson:"max_complexity" json:"max_complexity"`
+	Fields        []GraphQLFieldComplexityConfig `bson:"fields" json:"fields"`
+}
+
 type GraphQLConfig struct {
 	// Enabled indicates if GraphQL should be enabled.
 	Enabled bool `bson:"enabled" json:"enabled"`
@@ -1240,6 +1284,8 @@
 	Supergraph GraphQLSupergraphConfig `bson:"supergraph" json:"supergraph"`
 	// Introspection holds the configuration for GraphQL Introspection
 	Introspection GraphQLIntrospectionConfig `bson:"introspection" json:"introspection"`
+	// Complexity holds the configuration for graphql complexity and limitation
+	Complexity GraphQLComplexityConfig `bson:"complexity" json:"complexity"`
 }
     GraphQLConfig is the root config object for a GraphQL API.
 
@@ -1314,6 +1360,14 @@
 	// GraphQLExecutionModeSupergraph is the mode where an API is able to use subgraphs to build a supergraph in GraphQL federation.
 	GraphQLExecutionModeSupergraph GraphQLExecutionMode = "supergraph"
 )
+type GraphQLFieldComplexityConfig struct {
+	TypeName      string `bson:"type_name" json:"type_name"`
+	FieldName     string `bson:"field_name" json:"field_name"`
+	MaxNodes      int    `bson:"max_nodes" json:"max_nodes"`
+	MaxComplexity int    `bson:"max_complexity" json:"max_complexity"`
+	MaxDepth      int    `bson:"max_depth" json:"max_depth"`
+}
+
 type GraphQLFieldConfig struct {
 	TypeName              string   `bson:"type_name" json:"type_name"`
 	FieldName             string   `bson:"field_name" json:"field_name"`
@@ -6731,8 +6785,10 @@
 	ErrNoMatchingKIDFound    = errors.New("no matching KID could be found")
 )
 var (
-	ProxyingRequestFailedErr     = errors.New("there was a problem proxying the request")
-	GraphQLDepthLimitExceededErr = errors.New("depth limit exceeded")
+	ProxyingRequestFailedErr          = errors.New("there was a problem proxying the request")
+	GraphQLDepthLimitExceededErr      = errors.New("depth limit exceeded")
+	GraphQLNodeLimitExceededErr       = errors.New("max number of nodes exceeded")
+	GraphQLComplexityLimitExceededErr = errors.New("max graphql complexity reached")
 )
 var (
 	ErrNoSuitableUserIDClaimFound = errors.New("no suitable claims for user ID were found")

[sweep-ai[bot]]

Fixing PR: track the progress here.

I'm currently fixing this PR to address the following:

[Sweep GHA Fix] The GitHub Actions run failed with the following error logs:

✨ Created Pull Request: https://github.com/TykTechnologies/tyk/pull/5954

[sweep-ai[bot]]

Fixing PR: track the progress here.

I'm currently fixing this PR to address the following:

[Sweep GHA Fix] The GitHub Actions run failed with the following error logs:

[!CAUTION]

An error has occurred: Sweep could not find any files to modify (tracking ID: 4d60f486f4)

[sweep-ai[bot]]

Fixing PR: track the progress here.

I'm currently fixing this PR to address the following:

[Sweep GHA Fix] The GitHub Actions run failed with the following error logs:

✨ Created Pull Request: https://github.com/TykTechnologies/tyk/pull/5953

[sweep-ai[bot]]

Fixing PR: track the progress here.

I'm currently fixing this PR to address the following:

[Sweep GHA Fix] The GitHub Actions run failed with the following error logs:

✨ Created Pull Request: https://github.com/TykTechnologies/tyk/pull/5952