github.com/letsencrypt/trillian@v1.1.2-0.20180615153820-ae375a99d36a/quota/noop.go (about)

     1  // Copyright 2017 Google Inc. All Rights Reserved.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package quota
    16  
    17  import (
    18  	"context"
    19  	"fmt"
    20  )
    21  
    22  type noopManager struct{}
    23  
    24  const (
    25  	noopUser = "noopQuotaUser" // arbitrary string
    26  )
    27  
    28  // Noop returns a noop implementation of Manager. It allows all requests without restriction.
    29  func Noop() Manager {
    30  	return &noopManager{}
    31  }
    32  
    33  func (n noopManager) GetUser(ctx context.Context, req interface{}) string {
    34  	return noopUser
    35  }
    36  
    37  func (n noopManager) GetTokens(ctx context.Context, numTokens int, specs []Spec) error {
    38  	if err := validateNumTokens(numTokens); err != nil {
    39  		return err
    40  	}
    41  	return validateSpecs(specs)
    42  }
    43  
    44  func (n noopManager) PeekTokens(ctx context.Context, specs []Spec) (map[Spec]int, error) {
    45  	if err := validateSpecs(specs); err != nil {
    46  		return nil, err
    47  	}
    48  	tokens := make(map[Spec]int)
    49  	for _, spec := range specs {
    50  		tokens[spec] = MaxTokens
    51  	}
    52  	return tokens, nil
    53  }
    54  
    55  func (n noopManager) PutTokens(ctx context.Context, numTokens int, specs []Spec) error {
    56  	if err := validateNumTokens(numTokens); err != nil {
    57  		return err
    58  	}
    59  	return validateSpecs(specs)
    60  }
    61  
    62  func (n noopManager) ResetQuota(ctx context.Context, specs []Spec) error {
    63  	return validateSpecs(specs)
    64  }
    65  
    66  func (n noopManager) SetupInitialQuota(ctx context.Context, treeID int64) error {
    67  	return nil
    68  }
    69  
    70  func validateNumTokens(numTokens int) error {
    71  	if numTokens <= 0 {
    72  		return fmt.Errorf("invalid numTokens: %v (>0 required)", numTokens)
    73  	}
    74  	return nil
    75  }
    76  
    77  func validateSpecs(specs []Spec) error {
    78  	for _, spec := range specs {
    79  		switch {
    80  		case spec.Group == User && spec.User != noopUser:
    81  			return fmt.Errorf("invalid quota user: %v (expected %v)", spec.User, noopUser)
    82  		case spec.Group == Tree && spec.TreeID <= 0:
    83  			return fmt.Errorf("invalid tree ID: %v (expected >=0)", spec.TreeID)
    84  		}
    85  	}
    86  	return nil
    87  }