From 3bff555e0004d36b4e3fce18be0256dbfd2d0619 Mon Sep 17 00:00:00 2001 From: dongming Date: Wed, 14 Dec 2022 16:09:09 +0800 Subject: [PATCH] l-28 --- .../tools/cache/thread_safe_store.go | 29 +++++++++++++++---- 1 file changed, 24 insertions(+), 5 deletions(-) diff --git a/vendor/k8s.io/client-go/tools/cache/thread_safe_store.go b/vendor/k8s.io/client-go/tools/cache/thread_safe_store.go index 1182ea1..1799147 100644 --- a/vendor/k8s.io/client-go/tools/cache/thread_safe_store.go +++ b/vendor/k8s.io/client-go/tools/cache/thread_safe_store.go @@ -62,12 +62,13 @@ type ThreadSafeStore interface { // threadSafeMap implements ThreadSafeStore type threadSafeMap struct { lock sync.RWMutex - items map[string]interface{} + items map[string]interface{} // 真正存储数据的地方，加入，删除，更新都是操作这里的数据 // indexers maps a name to an IndexFunc - indexers Indexers + indexers Indexers // 存储的是索引的字段到获取索引的方法。如查询Pods的时候，按照namespace来查询，namespace就是这和索引字段 + // indices maps a name to an Index - indices Indices + indices Indices // 存储的是索引的字段到索引对象的方法。索引对象是从索引的具体值到存储数据的key值的映射 } func (c *threadSafeMap) Add(key string, obj interface{}) { @@ -79,6 +80,7 @@ func (c *threadSafeMap) Update(key string, obj interface{}) { defer c.lock.Unlock() oldObject := c.items[key] c.items[key] = obj + // 更新数据后，造成了索引的失效，所以需要更新 c.updateIndices(oldObject, obj, key) } @@ -86,7 +88,7 @@ func (c *threadSafeMap) Delete(key string) { c.lock.Lock() defer c.lock.Unlock() if obj, exists := c.items[key]; exists { - c.updateIndices(obj, nil, key) + c.updateIndices(obj, nil, key) // 删除造成索引变更，所以要更新索引 delete(c.items, key) } } @@ -120,11 +122,13 @@ func (c *threadSafeMap) ListKeys() []string { return list } +// 用新的数据，整个替换掉老的数据 func (c *threadSafeMap) Replace(items map[string]interface{}, resourceVersion string) { c.lock.Lock() defer c.lock.Unlock() c.items = items + // 重建索引 // rebuild any index c.indices = Indices{} for key, item := range c.items { @@ -132,12 +136,16 @@ func (c *threadSafeMap) Replace(items map[string]interface{}, resourceVersion st } } +// 通过索引来查询数据 // Index returns a list of items that match the given object on the index function. // Index is thread-safe so long as you treat all items as immutable. func (c *threadSafeMap) Index(indexName string, obj interface{}) ([]interface{}, error) { c.lock.RLock() defer c.lock.RUnlock() + // key 指的是找到“索引”的key + // “索引”是存储 key 到 items中key的映射 + // 通过索引名称，获取索引的值（就是key） indexFunc := c.indexers[indexName] if indexFunc == nil { return nil, fmt.Errorf("Index with name %s does not exist", indexName) @@ -147,8 +155,11 @@ func (c *threadSafeMap) Index(indexName string, obj interface{}) ([]interface{}, if err != nil { return nil, err } + + // 通过索引名称，获取索引（key-》对象的key） index := c.indices[indexName] + // 取得要查询的对象在 items 中的 key值的集合 var storeKeySet sets.String if len(indexedValues) == 1 { // In majority of cases, there is exactly one value matching. @@ -165,6 +176,7 @@ func (c *threadSafeMap) Index(indexName string, obj interface{}) ([]interface{}, } } + // 用过 key 的集合，取得数据 list := make([]interface{}, 0, storeKeySet.Len()) for storeKey := range storeKeySet { list = append(list, c.items[storeKey]) @@ -172,6 +184,7 @@ func (c *threadSafeMap) Index(indexName string, obj interface{}) ([]interface{}, return list, nil } +// 和Index作用相同，只是查询的参数不是 object，而是使用索引的值，这个值能在indeices中获取正确的索引对象 // ByIndex returns a list of the items whose indexed values in the given index include the given indexed value func (c *threadSafeMap) ByIndex(indexName, indexedValue string) ([]interface{}, error) { c.lock.RLock() @@ -193,6 +206,7 @@ func (c *threadSafeMap) ByIndex(indexName, indexedValue string) ([]interface{}, return list, nil } +// 仅仅返索引中的key，并没有去items中查询真正的数据 // IndexKeys returns a list of the Store keys of the objects whose indexed values in the given index include the given indexed value. // IndexKeys is thread-safe so long as you treat all items as immutable. func (c *threadSafeMap) IndexKeys(indexName, indexedValue string) ([]string, error) { @@ -247,6 +261,10 @@ func (c *threadSafeMap) AddIndexers(newIndexers Indexers) error { return nil } +// 更新方法包含： +// 新建： 只有 newObj 值，oldObj 值为 nil +// 更新： newObj，oldObj 都有值 +// 删除： 只有 oldObj，newObj 值为 nil // updateIndices modifies the objects location in the managed indexes: // - for create you must provide only the newObj // - for update you must provide both the oldObj and the newObj @@ -259,7 +277,7 @@ func (c *threadSafeMap) updateIndices(oldObj interface{}, newObj interface{}, ke if oldObj != nil { oldIndexValues, err = indexFunc(oldObj) } else { - oldIndexValues = oldIndexValues[:0] + oldIndexValues = oldIndexValues[:0] // 相当于清空 } if err != nil { panic(fmt.Errorf("unable to calculate an index entry for key %q on index %q: %v", key, name, err)) @@ -282,6 +300,7 @@ func (c *threadSafeMap) updateIndices(oldObj interface{}, newObj interface{}, ke if len(indexValues) == 1 && len(oldIndexValues) == 1 && indexValues[0] == oldIndexValues[0] { // We optimize for the most common case where indexFunc returns a single value which has not been changed + // 新老对象完全相同，就不操作 continue }