I have seen your question about the MovieDB application that I have used for exploring the features of Dropsource at long time ago.
For further information, I used TMDb’s API as mentioned above, followed their documentation and used Swagger Editor to generate the JSON file for upload to Dropsource. I have tried my best to look for the json file, but I have failed (a year already), sorry.
So, my suggest - if you still want to explore my source with Dropsource - then you could follow their document and generate new JSON file for upload. I just used GET APIs for videos listing and video detail.
P/s: I have follow @seanhoots’s suggestion. Yes, it seems Stoplight is a better tool to integrate 3rd party’s APIs for Dropsource. I should try it on next project.