If you want the same functionality as go-ds-flatfs, use sharding with fs.
constFsStore=require('datastore-fs')constShardingStore=require('datastore-core').ShardingDatastoreconstNextToLast=require('datastore-core').shard.NextToLastconstfs=newFsStore('path/to/store')// flatfs now works like go-flatfsconstflatfs=awaitShardingStore.createOrOpen(fs,newNextToLast(2))
Adapter
An adapter is made available to make implementing your own datastore easier:
const{ Adapter }=require('interface-datastore')classMyDatastoreextendsAdapter{constructor(){super()}asyncput(key,val){// your implementation here}asyncget(key){// your implementation here}// etc...}
Most API methods accept an AbortSignal as part of an options object. Implementations may listen for an abort event emitted by this object, or test the signal.aborted property. When received implementations should tear down any long-lived requests or resources created.
Concurrency
The streaming (put|get|delete)Many methods are intended to be used with modules such as it-parallel-batch to allow calling code to control levels of parallelisation. The batching method ensures results are returned in the correct order, but interface implementations should be thread safe.
constbatch=require('it-parallel-batch')constsource=[{key: ..,value: ..}]// put values into the datastore concurrently, max 10 at a timeforawait(const{ key, data }ofbatch(store.putMany(source),10)){console.info(`Put ${key}`)}
Keys
To allow a better abstraction on how to address values, there is a Key class which is used as identifier. It's easy to create a key from a Uint8Array or a string.
The key scheme is inspired by file systems and Google App Engine key model. Keys are meant to be unique across a system. They are typically hierarchical, incorporating more and more specific namespaces. Thus keys can be deemed 'children' or 'ancestors' of other keys:
new Key('/Comedy')
new Key('/Comedy/MontyPython')
Also, every namespace can be parameterized to embed relevant object information. For example, the Key name (most specific namespace) could include the object type:
new Key('/Comedy/MontyPython/Actor:JohnCleese')
new Key('/Comedy/MontyPython/Sketch:CheeseShop')
new Key('/Comedy/MontyPython/Sketch:CheeseShop/Character:Mousebender')
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