go.chromium.org/luci@v0.0.0-20240309015107-7cdc2e660f33/auth/internal/proc_cache.go (about)

     1  // Copyright 2017 The LUCI Authors.
     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 internal
    16  
    17  import (
    18  	"sync"
    19  )
    20  
    21  var (
    22  	// ProcTokenCache is shared in-process cache to use if disk cache is disabled.
    23  	ProcTokenCache TokenCache = &MemoryTokenCache{}
    24  )
    25  
    26  // MemoryTokenCache implements TokenCache on top of in-process memory.
    27  type MemoryTokenCache struct {
    28  	lock  sync.RWMutex
    29  	cache map[string]Token
    30  }
    31  
    32  // GetToken reads the token from cache.
    33  func (c *MemoryTokenCache) GetToken(key *CacheKey) (*Token, error) {
    34  	k := key.ToMapKey()
    35  	c.lock.RLock()
    36  	tok, ok := c.cache[k]
    37  	c.lock.RUnlock()
    38  	if ok {
    39  		return &tok, nil
    40  	}
    41  	return nil, nil
    42  }
    43  
    44  // PutToken writes the token to cache.
    45  func (c *MemoryTokenCache) PutToken(key *CacheKey, tok *Token) error {
    46  	k := key.ToMapKey()
    47  	c.lock.Lock()
    48  	if c.cache == nil {
    49  		c.cache = make(map[string]Token, 1)
    50  	}
    51  	c.cache[k] = *tok
    52  	c.lock.Unlock()
    53  	return nil
    54  }
    55  
    56  // DeleteToken removes the token from cache.
    57  func (c *MemoryTokenCache) DeleteToken(key *CacheKey) error {
    58  	k := key.ToMapKey()
    59  	c.lock.Lock()
    60  	delete(c.cache, k)
    61  	c.lock.Unlock()
    62  	return nil
    63  }