designing authorization provider

Author: michaeldcanady

internal/authorization_handler.go

@@ -0,0 +1,14 @@
+package internal
+
+type AuthorizationHandler struct {
+	handler  BaseHandler
+	provider AuthorizationProvider
+}
+
+func (a *AuthorizationHandler) Handle(request RequestInformation) error {
+	err := a.provider.AuthorizeRequest(request)
+	if err != nil {
+		return err
+	}
+	return a.handler.Handle(request)
+}

internal/authorization_provider.go

@@ -0,0 +1,24 @@
+package internal
+
+const (
+	AuthorizationHeader = "Authorization"
+)
+
+type Credential interface {
+	GetAuthentication() (string, error)
+}
+
+type AuthorizationProvider interface {
+	AuthorizeRequest(request RequestInformation) error
+}
+
+type BasicAuthorizationProvider struct {
+	credential Credential
+}
+
+func (b *BasicAuthorizationProvider) AuthorizeRequest(request RequestInformation) error {
+	header, err := b.credential.GetAuthentication()
+	if err != nil {
+		return err
+	}
+}

internal/errors.go

@@ -21,4 +21,7 @@ var (
 	ErrWrongResponseType = errors.New("incorrect Response Type")
 	ErrParsing           = errors.New("parsing nextLink url failed")
 	ErrNilCallback       = errors.New("callback can't be nil")
+
+	//Authorization Provider
+	ErrNilRequest = errors.New("request can't be nil")
 )

internal/helper.go

@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"io"
 	"net/http"
+	"reflect"
 )
 
 // FromJSON[T] Unmarshalls response body into v
@@ -40,3 +41,9 @@ func ParseResponse[T Response](response *http.Response, value T) error {
 
 	return nil
 }
+
+// IsNil checks if a value is nil or a nil interface
+func IsNil(a interface{}) bool {
+	defer func() { _ = recover() }()
+	return a == nil || reflect.ValueOf(a).IsNil()
+}

internal/request_handlers.go

@@ -0,0 +1,27 @@
+package internal
+
+type RequestHandler interface {
+	Handle(RequestInformation) error
+	SetNext(RequestHandler)
+	Next() RequestHandler
+}
+
+type BaseHandler struct {
+	next RequestHandler
+}
+
+// SetNext method for BaseHandler
+func (b *BaseHandler) SetNext(handler RequestHandler) {
+	b.next = handler
+}
+
+func (b *BaseHandler) Next() RequestHandler {
+	return b.next
+}
+
+func (b *BaseHandler) Handle(request RequestInformation) error {
+	if !IsNil(b.Next()) {
+		return b.Next().Handle(request)
+	}
+	return nil
+}

internal/request_information.go

@@ -0,0 +1,19 @@
+package internal
+
+import (
+	"bytes"
+	"context"
+	"net/http"
+	"net/url"
+)
+
+type RequestInformation interface {
+	SetStreamContent(content []byte)
+	AddQueryParameters(source interface{}) error
+	getContentReader() *bytes.Reader
+	SetUri(url *url.URL)  //nolint:stylecheck
+	Url() (string, error) //nolint:stylecheck
+	ToRequest() (*http.Request, error)
+	ToRequestWithContext(ctx context.Context) (*http.Request, error)
+	AddHeaders(rawHeaders interface{}) error
+}