Camel: Basic CAM features for OnShape

Introduction

Camel is a suite of CAM (Computer Aided Manufacturing) features for OnShape implemented in FeatureScript. It's an experimental hobby project that provides basic features for generating tool paths for driving CNC machines from within a Part Studio.

If you don't already have the Camel features installed, get them here.

Web application

This repository contains the Camel web application to help you download G-Code files generated by Camel from a right-side element panel in your OnShape Part Studios. Once you've downloaded the G-Code files, you can preview the results with a G-Code simulator such as Camotics or load them into your CNC software to begin manufacturing right away!

To use the Camel web application, you must subscribe to it in the OnShape App Store. It's free and open source.

Once you've subscribed to the application, you will find the new Camel panel in the right side of your OnShape Part Studios.

Permissions

Here's an explanation of the permissions requested by the application:

• Read from your documents: Only used to read variables that contain files generated by Camel features in your Part Studios.

How it works

Camel's post processor stores each file that it generates into a separate variable in your Part Studio named camelFile###. It also stores an index of these files in a variable named camelFileIndex.

You can see these variables in the OnShape variable view. Unfortunately, OnShape truncates long variables in that view so we need a different way to download their contents.

Each time you open the Camel panel, OnShape sends a request to this application to render the content to show in the panel. If necessary at the start of a session, this application sends a request back to OnShape to request authorization to use the OnShape API on your behalf. You will be prompted to grant permissions to this application at that time if you haven't already done so.

Once this application has received authorization, it calls Feature Script functions within your Part Studio to retrieve the file index and it presents a list of links to download or view the files.

Only you can access your own files. Your authorization tokens are only stored in the server's memory for the duration of your session; they are never stored anywhere else and they are never shared with anyone else.

Alternatives

If you choose not to use this web application, you can instead choose to copy-paste files directly from the OnShape Notices area. Simply enable the Write output to notices checkbox in the CAM Post process feature, save your changes, then open the Notices area to find your files.

Or you could use 'curl' or a similar program to download your files from the command-line using the OnShape API in your own way.

How to set up your own instance

If you don't want to use the production instance of Camel or if you'd like to make contributions, you can run your own instance. Here's how to do it.

You'll need to be familiar with Docker and with how to set up a web server.

• Visit the OnShape Developer Portal and click Create new OAuth application. You'll need to provide some information to identify your application. When finished, you will receive an OAuth2 client id and secret, save them for later and keep them private!
  • Name: A unique name for your instance. The production instance is called Camel.
  • production format: A unique identifier for your instance. The production instance is identified as camel.brownstudios.dev.
  • Redirect URLs: https://example.com/oauth/redirect (edit for your host name).
  • OAuth URL: https://example.com/oauth/signin (edit for your host name).
  • Permissions: Only needs read your documents.
• In the Extensions tab of the portal, click Add extension to add the necessary extensions.
  • Panel
    • Name: CAM panel
    • Location: Element right panel
    • Context: Inside part studio
    • Action URL: https://example.com/action/d/{$documentId}/{$workspaceOrVersion}/{$workspaceOrVersionId}/e/{$elementId}/panel?configuration={$configuration} (edit for your host name).
    • Icon: Upload icons/camel.svg.
• In the Details tab of the portal, click Create store entry to publish the application to the OnShape App Store. Fill in the form as required.
• Download the application's source code.
• Copy .env.example to .env.
• Edit .env as follows.
  • SESSION_ID_COOKIE_SECRET: Set this variable to a randomly generated string and keep it secret.
  • ONSHAPE_APP_CLIENT_ID: Set this variable to the OAuth2 client identifier you received from the OnShape Developer Portal. Make sure to copy the string precisely, including any trailing = signs.
  • ONSHAPE_APP_CLIENT_SECRET: Set this variable to the OAuth2 client secret you received from the OnShape Developer Portal and keep it secret. Make sure to copy the string precisely, including any trailing = signs.
  • EXTERNAL_HOSTNAME: Set this variable to the host name of the web server you will run the application on. The production instance is at camel.brownstudios.dev.
• Obtain an SSL certificate for your host name using a method of your choice and copy your certificate to data/certs/cert.pem and your private key to data/certs/privkey.pem. If you have certbot installed, you can run the update-certs.sh shell script to automatically obtain an SSL certificate from Let's Encrypt and store it in the correct location.
• Build the Docker image: docker-compose build.
• Run the Docker image: docker-compose up.
• A few months later when it's time to renew your SSL certificates, run the restart-with-updated-certs.sh script to stop the service, update your certificates from Let's Encrypt, and start the service again.

Then visit your app's page in the OnShape App Store, subscribe to your shiny new app, grant it permissions, and have fun!