Page History

...

1. As CollectionAlias works as an extra pointer to the existing collection in the RootCoordinator, we can implement collection hot reloading at a low cost.
2. When AddAlias, DropAlias and AlterAlias, the change of relationship between alias and collection should not affect the operations online, i.e. these operations shoud use the relationship when the task begin to excute.
3. When AddAlias, DropAlias and AlterAlias, all proxy should receive the change in the same timestamp to ensure the atomicity between the proxy cache and the rootcoord data.
4. Users can't drop the collection if the collection is referenced by an alias, which can simplify the operation and make it easier to ensure the atomicity property about alias changes.

Public Interfaces

Change to Existing APIs

• Metatable now add ts2alias2name and newestAliasTs member variables

type immutablemap_string2string struct{
    storemap    map[string]string
}

func (imstr2str * immutablemap_string2string) get(key string) (string, error){
    rstr,ok := imstr2str.storemap[key]
    if(!ok){
        return nil, fmt.Errorf("key not exist")
    }
    return rstr, nil
}

func (imstr2str * immutablemap_string2string) put(key string, val string) (string, error){
    return nil, fmt.Errorf("not allowed put in immutablemap")
}

type metatable struct{
    ...
    ts2alias2name map[Timestamp]immutablemap_string2string
    newestAliasTs Timestamp
    ...
}