Best way to connect an Qt/C++ model to GLSP frontend ?

[timwelapt]

Hello, can I get some guidance here what are reasonable options to get my Qt/C++/MySQL model connected to the GLSP framework ?

I am currently scanning the sources and following the GLSP documentation (https://eclipse.dev/glsp/documentation/sourcemodel/) to find out how to bind customs models, but for me JS/TS is completely new and so it is hard to see solutions to connect the functions properly between GLSP and C++ application. Are there concrete hints or examples known for C++ Apps ?

Do you see roadblocks for interconnecting ?

Background/JFYI: I want to evaluate an Service-Oriented-Architecture on a System-Level approach, it is just a Proof-of-Concept, so the effort for this activity needs to stay small. I thought using GLSP might be a good path to go for a modern and maintained web/cloud frontend approach, instead of extending some Qt-Widgets on my own. Continuing using 100% Qt might get some Diagram-HMI, but very limited and slow to extend. On the other side, using 100% JS/TS also for the model and probably a more JS-like database, would be very hard porting as I am new in JS/TS.

[planger]

Hi,

Connecting your Qt/C++/MySQL model to the GLSP framework should doable, and you have several options depending on how tightly you want to couple your C++ application with the GLSP server.

The GLSP server processes model data and transforms it into a form that the GLSP client can render. This involves:

• Reading the Source Model: Accessing your data from the source (C++ application/MySQL database).
• Transforming the Model: Using a GModelFactory to transform the data into the GModel format.
• Handling Operations: Implementing operation handlers to modify the source model if needed.

Options for Integration

1. Direct Database Connection

If your data is stored in a MySQL database, you can connect directly from the GLSP server:

• Set Up the GLSP Server: Use a Java or TypeScript-based GLSP server.
• Database Access: Use JDBC (for Java) or a Node.js MySQL client (for TypeScript) to access the database.
• SourceModelStorage and GModelFactory Implementation: In your custom SourceModelStorage implementation, you can query the data from the database and put it into your model state (see source model documentation). Then you'd need to implement a factory that translates this data it into the GModel specifying what to render on the client

2. Inter-Process Communication (IPC)

For leveraging significant business logic in your C++ application, use IPC mechanisms like REST APIs or sockets:

• REST API: Implement a REST API in your C++ application and fetch data from the GLSP server.
• Socket Communication: Establish a socket connection for real-time data exchange between your C++ application and the GLSP server.

3. File-Based Integration

Write data from your C++ application to a JSON file and have the GLSP server read this file:

• Write Data to JSON: Your C++ application writes the model data to a JSON file.
• Read JSON in GLSP Server: The GLSP server reads and transforms the JSON data into the GModel format.

Synchronization and Editing

To support editing operations, implement GLSP operation handlers that sync changes back to your source model. This could involve updating the database directly or sending changes back to the C++ application via IPC or writing into the shared file.

Conclusion

For a quick proof-of-concept, directly connecting to the MySQL database from the GLSP server is a straightforward approach. If you need to leverage existing business logic in your C++ application, consider using IPC mechanisms.

Refer to the GLSP Documentation for more details on hooking up your data, implementing the GModelFactory, and handling operations.