MongoDB is a NoSQL database systemdocument-oriented, life-changing for many developers, allowing them to build applications faster than relational databases. However, MongoDB has abandoned its open source roots, changing the license to SSPL, making it unusable for many commercial and open source projects.
Before this, MangoDB was presented, which is a perfect solution for those looking for a MongoDB development experience, as MangoDB offers a layer with the document-oriented MongoDB protocol implementation that runs on top of PostgreSQL.
The project aims to provide the ability to migrate MongoDB applications to PostgreSQL and a fully open software stack. The code is written in the Go language and is distributed under the Apache 2.0 license.
Keep in mind that MongoDB is a document-oriented database administration system It can be distributed over any number of computers and does not require a predefined data schema. Which allows to handle structured objects in BSON format (binary JSON), without a default schema.
In other words, keys can be added at any time "on the fly", without reconfiguring the base. The data takes the form of documents which are in turn stored in collections, a collection containing any number of documents. Collections are like tables and documents are like records in relational databases.
The server-side public license (SSPL) is a proprietary software license developed by MongoDB Inc. According to MongoDB, the SSPL is based on the AGPL3 license, with the addition of a new section that "clearly and explicitly establishes the terms for distributing the licensed program as a third-party service," requiring that all source code be available when the software is made available to the public as part of a service.
This change was rolled out in October 2018, to which the Debian, Red Hat Enterprise Linux, and Fedora distributions subsequently abandoned MongoDB, citing concerns about SSPL. Amazon released a supported but proprietary service called DocumentDB, and it appeared that SSPL was unable to increase cloud revenue for MongoDB. Most MongoDB users don't need the many advanced features that MongoDB offers, but they do need an open source database solution and this is where MangoDB comes into play.
The core of our solution is a stateless proxy, which converts MongoDB protocol queries to SQL and uses PostgreSQL as the database engine. It will be compatible with MongoDB drivers and in many cases it should work as a direct replacement for MongoDB.
MangoDB aims to become the de facto open source alternative to MongoDB. MangoDB is an open source proxy, which converts MongoDB wired protocol queries to SQL and uses PostgreSQL as the database engine. MangoDB will be compatible with MongoDB drivers and will work as a direct replacement for MongoDB in many cases.
The program works as a proxy that translates calls to MangoDB into SQL queries to PostgreSQL, using PostgreSQL as real storage. The project supports drivers for MongoDB, but it is still in the prototype stage and does not support the advanced features of the MongoDB protocol, although it is already suitable for translating simple applications.
The need to avoid the use of the MongoDB DBMS may arise due to the transition of the project to a non-free SSPL license, which is based on the AGPLv3 license, but is not open, as it contains a discriminatory requirement to supply under SSPL not only the code of the application itself, but also the source codes of all the components involved in the provision of cloud services.
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