github.com/cloudwego/kitex@v0.9.0/pkg/acl/acl.go (about)

     1  /*
     2   * Copyright 2021 CloudWeGo Authors
     3   *
     4   * Licensed under the Apache License, Version 2.0 (the "License");
     5   * you may not use this file except in compliance with the License.
     6   * You may obtain a copy of the License at
     7   *
     8   *     http://www.apache.org/licenses/LICENSE-2.0
     9   *
    10   * Unless required by applicable law or agreed to in writing, software
    11   * distributed under the License is distributed on an "AS IS" BASIS,
    12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13   * See the License for the specific language governing permissions and
    14   * limitations under the License.
    15   */
    16  
    17  // Package acl implements ACL functionality.
    18  package acl
    19  
    20  import (
    21  	"context"
    22  	"errors"
    23  
    24  	"github.com/cloudwego/kitex/pkg/endpoint"
    25  	"github.com/cloudwego/kitex/pkg/kerrors"
    26  )
    27  
    28  // RejectFunc judges if to reject a request by the given context and request.
    29  // Returns a reason if rejected, otherwise returns nil.
    30  type RejectFunc func(ctx context.Context, request interface{}) (reason error)
    31  
    32  // NewACLMiddleware creates a new ACL middleware using the provided reject funcs.
    33  func NewACLMiddleware(rules []RejectFunc) endpoint.Middleware {
    34  	if len(rules) == 0 {
    35  		return endpoint.DummyMiddleware
    36  	}
    37  	return func(next endpoint.Endpoint) endpoint.Endpoint {
    38  		return func(ctx context.Context, request, response interface{}) error {
    39  			for _, r := range rules {
    40  				if e := r(ctx, request); e != nil {
    41  					if !errors.Is(e, kerrors.ErrACL) {
    42  						e = kerrors.ErrACL.WithCause(e)
    43  					}
    44  					return e
    45  				}
    46  			}
    47  			return next(ctx, request, response)
    48  		}
    49  	}
    50  }