About OCCI

Open CAD Components Interface (OCCI) brings parametric components to all by using script CAD engines like CadQuery and Archiyou. Script CAD is very suitable to deliver platform-independant 'open design' parametric CAD content and we hope that OCCI will contribute to that.

The simplest way to try OCCI is with our FreeCAD plugin. You can find the OCCI design principles and spec here.

OCCI server

This repository contains a reference server stack that allows CAD scripts (currently we support CadQuery and Archiyou scripts) to be quickly turned into an OCCI API.

Use cases:

• You have a CAD script for which you want to build a viewing/configurator web-application
• You have a lot of CAD scripts that you want to share with other online

Developer Quickstart

The stack is fully dockerized. To start up a local OCCI server with a default CadQuery worker:

1. git clone https://github.com/occi-cad/occi-server.git
2. Add a .env file to the main directory based on env.example
3. Add scripts into the 'scriptlibrary' directory in format ./scriptlibrary/{org}/{name}/{version}/{name}.py|js and {name}.json for the config file. There is an OCCI example library to get you started. Make sure you are in the root directory:

git clone https://github.com/occi-cad/scriptlibrary

4. Go into a terminal and run:

    docker-compose up

5. Once everything is started up and connected go to localhost:8090 to see the OCCI server basic information
6. Get your first parametric model from OCCI example library. Go to url: http://localhost:8090/tests/box. This will give you a parametric box in STEP file. Use http://localhost:8090/tests/box?output=full to see more information.

Using an OCCI API

We have auto-generated API docs. Go to http://localhost:8090/docs on your OCCI server for all query possibilities. Here are the basics:

1. Get script: {ROOT}/{org}/{name} - Access the default version of a script
   • format=step|stl|gltf - File format of model (GLTF not supported in CQ for now!)
   • output=full|model - return a full JSON response or just the model file in given format (default=STEP)
2. Search: {ROOT}/search?q={search_string}

Manage and configure your CAD scripts

To quickly turn your CAD scripts into an API:

1. Create a directory scriptlibrary if not exists
2. Place your scripts (for example mybox.py for Cadquery) in a folder structure like this: scriptlibrary/{org/author}/{scriptname}/{version}/{scriptname}.py for example: scriptlibrary/mycadcompany/mybox/0.5/mybox.py
3. Also add a simple configuration JSON file called mybox.json in that directory with the following basic information:

{
    "description" : "A simple test box",
    "params" : { 
        "size" : {
            "type": "number",
            "start" : 1,
            "end" : 100,
            "default" : 50,
            "description" : "The size of the box",
            "units" : "mm"
        }
    },
    "param_presets": {
        "small": { "size" : 5 },
        "medium": { "size" : 50 },
        "big": { "size" : 100 }
    },
    "license" : "CC0"
}

This will make the box parametric and enable OCCI API to check inputs

4. If you run the occi-server stack (see Developer Quickstart) your script should be available at localhost:8090/mycadcompany/mybox/0.5/mybox

You can configure the parameters to your scripts in multiple ways. Currently these parameter types are supported:

• number - 'start' to 'end' with 'step'
• boolean
• text - optional: 'max_length', 'min_length'
• options - with 'values' with a list of strings

For more information on optional content of the *.json config file see CadScript.py in occilib/

Deploy in Production

Use 'docker-compose.prod.yml' if you want to host a OCCI server with a HTTPS certificate and Nginx webserver:

1. Go to nginx.conf and fill in your domain information

    server_name myocci.server.org;

    # Load the certificate files.
    ssl_certificate         /etc/letsencrypt/live/myocci.server.org/fullchain.pem;
    ssl_certificate_key     /etc/letsencrypt/live/myocci.server.org/privkey.pem;
    ssl_trusted_certificate /etc/letsencrypt/live/myocci.server.org/chain.pem;

2. Make sure the URL in nginx.conf works and resolves to your current server
3. Start the OCCI server:

 docker-compose -f docker-compose.prod.yml up -d

4. The stack should start, a certificate is obtained and the server would start much as in local development

Open Toolchain Foundation

This project is supported by the Open Toolchain Foundation (OTF) and has contributors from the CadQuery and Archiyou teams.

Licence

Apache2