Merge pull request #1170 from sgayangi/sgayangi-header-modifier

[APK] Add implementation for HTTPRoute filters

apim-apk-agent/pkg/managementserver/rest_server.go

@@ -27,7 +27,6 @@ import (
 	"github.com/gin-gonic/gin"
 	"github.com/wso2/product-apim-tooling/apim-apk-agent/config"
 	logger "github.com/wso2/product-apim-tooling/apim-apk-agent/pkg/loggers"
-
 	"github.com/wso2/product-apim-tooling/apim-apk-agent/pkg/utils"
 	"gopkg.in/yaml.v2"
 )
@@ -312,20 +311,58 @@ func createDeployementYaml(vhost string) string {
 
 // APIOperation represents the desired struct format for each API operation
 type APIOperation struct {
-	ID                string   `yaml:"id"`
-	Target            string   `yaml:"target"`
-	Verb              string   `yaml:"verb"`
-	AuthType          string   `yaml:"authType"`
-	ThrottlingPolicy  string   `yaml:"throttlingPolicy"`
-	Scopes            []string `yaml:"scopes"`
-	UsedProductIDs    []string `yaml:"usedProductIds"`
-	OperationPolicies struct {
-		Request  []string `yaml:"request"`
-		Response []string `yaml:"response"`
-		Fault    []string `yaml:"fault"`
-	} `yaml:"operationPolicies"`
+	ID                string            `yaml:"id"`
+	Target            string            `yaml:"target"`
+	Verb              string            `yaml:"verb"`
+	AuthType          string            `yaml:"authType"`
+	ThrottlingPolicy  string            `yaml:"throttlingPolicy"`
+	Scopes            []string          `yaml:"scopes"`
+	UsedProductIDs    []string          `yaml:"usedProductIds"`
+	OperationPolicies OperationPolicies `yaml:"operationPolicies"`
+}
+
+// OperationPolicies contains the request, response and fault policies for an operation
+type OperationPolicies struct {
+	Request  []OperationPolicy `yaml:"request"`
+	Response []OperationPolicy `yaml:"response"`
+	Fault    []string          `yaml:"fault"`
+}
+
+// OperationPolicy represents the desired struct format for an Operation Policy
+type OperationPolicy struct {
+	PolicyName    string           `yaml:"policyName"`
+	PolicyVersion string           `yaml:"policyVersion"`
+	PolicyID      string           `yaml:"policyId,omitempty"`
+	Parameters    FilterParameters `yaml:"parameters"`
+}
+
+// FilterParameters interface is used to define the type of parameters that can be used in an operation policy.
+type FilterParameters interface {
+	isFilterParameters()
+}
+
+func (h Header) isFilterParameters() {}
+
+// Header contains the request and response header modifier information
+type Header struct {
+	Name  string `json:"headerName" yaml:"headerName"`
+	Value string `json:"headerValue,omitempty" yaml:"headerValue,omitempty"`
 }
 
+// RedirectRequest contains the url to send the redirected request
+type RedirectRequest struct {
+	URL string `json:"url"`
+}
+
+func (r RedirectRequest) isFilterParameters() {}
+
+// MirrorRequest contains the url to mirror the request to
+type MirrorRequest struct {
+	URL string `json:"url"`
+}
+
+func (m MirrorRequest) isFilterParameters() {}
+
 // OpenAPIPaths represents the structure of the OpenAPI specification YAML file
 type OpenAPIPaths struct {
 	Paths map[string]map[string]interface{} `yaml:"paths"`
@@ -364,6 +401,8 @@ type Scope struct {
 
 func extractOperations(event APICPEvent) ([]APIOperation, []ScopeWrapper, error) {
 	var apiOperations []APIOperation
+	var requestOperationPolicies []OperationPolicy
+	var responseOperationPolicies []OperationPolicy
 	scopewrappers := map[string]ScopeWrapper{}
 	if strings.ToUpper(event.API.APIType) == "GRAPHQL" {
 		for _, operation := range event.API.Operations {
@@ -401,12 +440,115 @@ func extractOperations(event APICPEvent) ([]APIOperation, []ScopeWrapper, error)
 						Shared: false,
 					}
 				}
+				// Process filters
+				for _, operationLevelFilter := range operationFromDP.Filters {
+					switch filter := operationLevelFilter.(type) {
+					// Header modification policies
+					case *APKHeaders:
+						requestHeaders := filter.RequestHeaders
+						// Add headers
+						if requestHeaders.AddHeaders != nil && len(requestHeaders.AddHeaders) > 0 {
+							logger.LoggerMgtServer.Debugf("Processing request filter for header addition")
+							for _, requestHeader := range requestHeaders.AddHeaders {
+								operationPolicy := OperationPolicy{
+									PolicyName:    "ccAddHeader",
+									PolicyVersion: "v2",
+									Parameters: Header{
+										Name:  requestHeader.Name,
+										Value: requestHeader.Value,
+									},
+								}
+								requestOperationPolicies = append(requestOperationPolicies, operationPolicy)
+							}
+						}
+
+						// Remove headers
+						if requestHeaders.RemoveHeaders != nil && len(requestHeaders.RemoveHeaders) > 0 {
+							logger.LoggerMgtServer.Debugf("Processing request filter for header removal")
+							for _, requestHeader := range requestHeaders.RemoveHeaders {
+								operationPolicy := OperationPolicy{
+									PolicyName:    "ccRemoveHeader",
+									PolicyVersion: "v2",
+									Parameters: Header{
+										Name: requestHeader,
+									},
+								}
+								requestOperationPolicies = append(responseOperationPolicies, operationPolicy)
+							}
+						}
+
+						responseHeaders := filter.ResponseHeaders
+						// Add headers
+						if responseHeaders.AddHeaders != nil && len(responseHeaders.AddHeaders) > 0 {
+							logger.LoggerMgtServer.Debugf("Processing response filter for header addition")
+							for _, responseHeader := range responseHeaders.AddHeaders {
+								operationPolicy := OperationPolicy{
+									PolicyName:    "ccAddHeader",
+									PolicyVersion: "v2",
+									Parameters: Header{
+										Name:  responseHeader.Name,
+										Value: responseHeader.Value,
+									},
+								}
+								responseOperationPolicies = append(responseOperationPolicies, operationPolicy)
+							}
+						}
+
+						// Remove headers
+						if responseHeaders.RemoveHeaders != nil && len(responseHeaders.RemoveHeaders) > 0 {
+							logger.LoggerMgtServer.Debugf("Processing response filter for header removal")
+							for _, responseHeader := range responseHeaders.RemoveHeaders {
+								operationPolicy := OperationPolicy{
+									PolicyName:    "ccRemoveHeader",
+									PolicyVersion: "v2",
+									Parameters: Header{
+										Name: responseHeader,
+									},
+								}
+								responseOperationPolicies = append(responseOperationPolicies, operationPolicy)
+							}
+						}
+					// Mirror request
+					case *APKMirrorRequest:
+						logger.LoggerMgtServer.Debugf("Processing request filter for request mirroring")
+						for _, url := range filter.URLs {
+							operationPolicy := OperationPolicy{
+								PolicyName:    "ccMirrorRequest",
+								PolicyVersion: "v1",
+								Parameters: MirrorRequest{
+									URL: url,
+								},
+							}
+							requestOperationPolicies = append(requestOperationPolicies, operationPolicy)
+						}
+
+					// Redirect request
+					case *APKRedirectRequest:
+						logger.LoggerMgtServer.Debugf("Processing request filter for request redirection")
+						operationPolicy := OperationPolicy{
+							PolicyName:    "ccRedirectRequest",
+							PolicyVersion: "v1",
+							Parameters: MirrorRequest{
+								URL: filter.URL,
+							},
+						}
+						requestOperationPolicies = append(requestOperationPolicies, operationPolicy)
+
+					default:
+						logger.LoggerMgtServer.Errorf("Unknown filter type ")
+					}
+				}
+
 				apiOp := APIOperation{
 					Target:           path,
 					Verb:             verb,
 					AuthType:         "Application & Application User",
 					ThrottlingPolicy: "Unlimited",
 					Scopes:           scopes,
+					OperationPolicies: OperationPolicies{
+						Request:  requestOperationPolicies,
+						Response: responseOperationPolicies,
+					},
 				}
 				apiOperations = append(apiOperations, apiOp)
 			}

apim-apk-agent/pkg/managementserver/types.go

@@ -146,13 +146,74 @@ type API struct {
 	Operations       []OperationFromDP `json:"operations"`
 }
 
+// APKHeaders contains the request and response header modifier information
+type APKHeaders struct {
+	Policy
+	RequestHeaders  APKHeaderModifier `json:"requestHeaders"`
+	ResponseHeaders APKHeaderModifier `json:"responseHeaders"`
+}
+
+// APKHeaderModifier contains header modifier values
+type APKHeaderModifier struct {
+	AddHeaders    []APKHeader `json:"addHeaders"`
+	RemoveHeaders []string    `json:"removeHeaders"`
+}
+
+// APKHeader contains the header information
+type APKHeader struct {
+	Name  string `json:"headerName" yaml:"headerName"`
+	Value string `json:"headerValue,omitempty" yaml:"headerValue,omitempty"`
+}
+
 // OperationFromDP holds the path, verb, throttling and interceptor policy
 type OperationFromDP struct {
-	Path   string   `json:"path"`
-	Verb   string   `json:"verb"`
-	Scopes []string `json:"scopes"`
+	Path    string   `json:"path"`
+	Verb    string   `json:"verb"`
+	Scopes  []string `json:"scopes"`
+	Filters []Filter `json:"filters"`
 }
 
+// Policy holds the policy name and version
+type Policy struct {
+	PolicyName    string `json:"policyName"`
+	PolicyVersion string `json:"policyVersion"`
+}
+
+// Filter interface is used to define the type of parameters that can be used in an operation policy
+type Filter interface {
+	GetPolicyName() string
+	GetPolicyVersion() string
+	isFilter()
+}
+
+// GetPolicyName returns the name of the policy sent to the APIM
+func (p *Policy) GetPolicyName() string {
+	return p.PolicyName
+}
+
+// GetPolicyVersion returns the version of the policy sent to the APIM
+func (p *Policy) GetPolicyVersion() string {
+	return p.PolicyVersion
+}
+
+func (h APKHeaders) isFilter() {}
+
+// APKRedirectRequest defines the parameters of a redirect request policy sent from the APK
+type APKRedirectRequest struct {
+	Policy
+	URL string `json:"url"`
+}
+
+func (r APKRedirectRequest) isFilter() {}
+
+// APKMirrorRequest defines the parameters of a mirror request policy sent from the APK
+type APKMirrorRequest struct {
+	Policy
+	URLs []string `json:"urls"`
+}
+
+func (m APKMirrorRequest) isFilter() {}
+
 // CORSPolicy hold cors configs
 type CORSPolicy struct {
 	AccessControlAllowCredentials bool     `json:"accessControlAllowCredentials,omitempty"`

apim-apk-agent/pkg/transformer/api_model.go

@@ -83,8 +83,41 @@ type Parameter interface {
 	isParameter()
 }
 
+// URLList contains the urls for mirror and redirect request policies
+type URLList struct {
+	URL  string   `json:"url,omitempty" yaml:"url,omitempty"`
+	URLs []string `json:"urls,omitempty" yaml:"urls,omitempty"`
+}
+
+func (u URLList) isParameter() {}
+
+// HeaderList contains the list of headers for header modification
+type HeaderList struct {
+	Headers []Header
+	Names   []string
+}
+
+// MarshalYAML for both []Header and []string
+func (h HeaderList) MarshalYAML() (interface{}, error) {
+	if len(h.Headers) > 0 {
+		return map[string]interface{}{"headers": h.Headers}, nil
+	}
+	if len(h.Names) > 0 {
+		return map[string]interface{}{"headers": h.Names}, nil
+	}
+	return nil, nil
+}
+
+// Header contains the information for header modification
+type Header struct {
+	HeaderName  string `yaml:"name"`
+	HeaderValue string `yaml:"value,omitempty"`
+}
+
+func (h HeaderList) isParameter() {}
+
 // InterceptorService holds configuration details for configuring interceptor
-// for a aperticular API requests or responses.
+// for particular API requests or responses.
 type InterceptorService struct {
 	BackendURL      string `yaml:"backendUrl,omitempty"`
 	HeadersEnabled  bool   `yaml:"headersEnabled,omitempty"`

apim-apk-agent/pkg/transformer/constants.go

@@ -64,4 +64,51 @@ const (
 	// Optionality constants
 	mandatory = "mandatory"
 	optional  = "optional"
+
+	// APIM Mediation constants
+	interceptorService = "ccCallInterceptorService"
+	backendJWT         = "BackEndJWT"
+	addHeader          = "ccAddHeader"
+	removeHeader       = "ccRemoveHeader"
+	mirrorRequest      = "ccMirrorRequest"
+	redirectRequest    = "ccRedirectRequest"
+
+	// Interceptor constants
+	requestHeader                 = "request_header"
+	requestBody                   = "request_body"
+	requestTrailers               = "request_trailers"
+	requestContext                = "request_context"
+	includes                      = "includes"
+	interceptorServiceURL         = "interceptorServiceURL"
+	https                         = "https"
+	requestInterceptorSecretName  = "request-interceptor-tls-secret"
+	responseInterceptorSecretName = "response-interceptor-tls-secret"
+	tlsKey                        = "tls.crt"
+
+	// BackendJWT constants
+	encoding         = "encoding"
+	header           = "header"
+	signingAlgorithm = "signingAlgorithm"
+	tokenTTL         = "tokenTTL"
+	base64Url        = "Base64Url"
+
+	// APK Operation Policy constants
+	interceptorPolicy     = "Interceptor"
+	backendJWTPolicy      = "BackendJwt"
+	addHeaderPolicy       = "AddHeaders"
+	removeHeaderPolicy    = "RemoveHeaders"
+	requestRedirectPolicy = "RequestRedirect"
+	requestMirrorPolicy   = "RequestMirror"
+
+	// APK BackendJWT parameter constants
+	base64url = "Base64url"
+
+	// APK header modification parameter constants
+	url         = "url"
+	headerName  = "headerName"
+	headerValue = "headerValue"
+
+	// Version constants
+	v1 = "v1"
+	v2 = "v2"
 )