The architecture of PouchDB is designed to support offline-first applications and seamless data synchronization between client-side and server-side databases. Here's an overview of its architecture:
Client-Side Database :
* At its core, PouchDB is a JavaScript database that runs within web browsers and other JavaScript runtime environments such as Node.js.
* PouchDB provides an API for storing, querying, and manipulating documents locally on the user's device.
* The client-side database is typically used to store application data and provide offline access to users.
Storage Backends :
* PouchDB supports multiple storage backends, including IndexedDB, WebSQL, and LevelDB, depending on the browser and environment.
* These storage backends provide the underlying mechanism for storing data persistently on the user's device.
Replication :
* One of the key features of PouchDB is its replication capability, which enables bidirectional synchronization of data between the client-side and server-side databases.
* PouchDB uses CouchDB's replication protocol to synchronize data with compatible databases, such as Apache CouchDB or other databases that support the replication protocol.
* Replication can occur in real-time, ensuring that changes made to the data on either side are quickly propagated to the other side once a network connection is available.
Conflict Resolution :
* PouchDB provides mechanisms for handling conflicts that may arise during data replication, such as conflicting updates to the same document on multiple devices.
* By default, PouchDB uses a Last-Write-Wins (LWW) conflict resolution strategy, where the most recent change takes precedence.
* Developers can implement custom conflict resolution policies based on their application's requirements to handle conflicts more effectively.
Eventual Consistency :
* PouchDB aims to achieve eventual consistency between the client-side and server-side databases, meaning that over time, all changes made to the data will be replicated and applied consistently across all devices.
* The replication process may involve multiple rounds of synchronization to ensure that all changes are eventually propagated to all replicas.
Integration with Front-End Frameworks :
* PouchDB can be easily integrated with various front-end frameworks and libraries, such as React, Angular, or Vue.js, to build offline-first web applications.
* Developers can use PouchDB's APIs within their application code to manage data storage, replication, and synchronization seamlessly.
