Reload mock server on example changes

[lehphyro]

User story.
As a developer, I can change a referenced example file, so that I can see the changes after a request to prism.

Is your feature request related to a problem?
Prism only watches the spec file for changes and even if it changes, it doesn't reload referenced examples. This is useful because spec files can get extremely big so $ref usage is a must to keep it manageable.

Describe the solution you'd like
Given a spec like this:

/test:
  get:
    ...
    responses:
      '200':
        ...
        examples:
          example1:
            value:
              $ref: examples/test1.json

Prism should watch examples/test1.json for changes and reload it or restart itself so that the changes are returned by it in the next request.

[XVincentX]

Oh ok I understand your use case. I'm not too sure wether we can make it happen with the current architecture.

The CLI does not resolve the file content, making a little bit hard to track all the files on the disk and react accordingly. I do see the value in the feature though. I'm going to try to have a look at it.

[philsturgeon]

@lehphyro I would love to see this, great idea!

@XVincentX The new ref resolver is working on a way to keep track of what the old files were pre-resolve. APIDevTools/json-schema-ref-parser#173

When we switch to that ref resolver, maybe we can use this new feature in order to keep track of the initial files, then place a watch on all of them to look for changes and reload?

[XVincentX]

@philsturgeon Prism is already using the new resolved, it would just probably matter of using the feature correctly in it. At the moment Prism-Http is making the assumption that the document is fully resolved, and that prevents us in general to take care of references after it has started.

In order to make this correctly we will probably have to rethink this concept and make the http package a little bit smarter.

[InfoSec812]

I too would like to see this, and further it would be great if Prism would update on ANY change to a local Spec file.

[InfoSec812]

Oh hey! I just found a nice workaround for this... Try this:

{​​​​​​​
  "name": "angular-openapi-prism",
  "version": "0.0.1",
  "scripts": {​​​​​​​
    "prism": "nodemon -w openapi.yml --exec 'prism mock -d --cors openapi.yml'",
    "openapi": "openapi-generator-cli generate -g typescript-angular -i openapi.yml -o src/sdk/"
  }​​​​​​​,
  "watch": {​​​​​​​
    "openapi": "openapi.yml"
  }​​​​​​​,
  "devDependencies": {​​​​​​​
    "nodemon": "^2.0.7",
    "npm-watch": "^0.7.0",
    "@openapitools/openapi-generator-cli": "^2.1.25",
    "@stoplight/prism-cli": "^4.1.2",
  }​​​​​​​
}​​​​​​​

This will use nodemon to "watch" the OpenAPI Spec and restart prism when there is a change.

[philsturgeon]

Autoreload on change was added in #689.