Integrate OpenAPI 3 into Dredd

[kylef]

This issue is tracking integrating OpenAPI 3 support into Dredd.

Caveats

The current support is not finished but we want to get OpenAPI 3 to you as quick as we can. We're doing this in the open which allows you to follow the progress, give us early feedback and allows you to contribute desired functionality.

There are some caveats with Dredd support in the current release, most should be addressed next week:

• Validation of response body is done from an example value(s) in content. Includes schemas are not used for validation.

See below for a working example of current functionality.

Important Missing Functionality

• Generating JSON Schema from OpenAPI 3 Schema

See our status page for furher information on supported functionality.

Examples

Success

openapi: '3.0.0'
info:
  title: HTTPBin
  version: 0.1.0
paths:
  /get:
    get:
      responses:
        '200':
          content:
            application/json:
              example:
                args: {}
                headers:
                  Connection: close
                  Host: httpbin.org
                  User-Agent: Dredd/0.0.0-semantically-released (Darwin 18.2.0; x64)
                origin: '::1'
                url: https://httpbin.org/get

$ dredd httpbin.yaml https://httpbin.org/
info: Beginning Dredd testing...
info: Found Hookfiles:
pass: GET (200) /get duration: 526ms
complete: 1 passing, 0 failing, 0 errors, 0 skipped, 1 total
complete: Tests took 529ms

Failure

openapi: '3.0.0'
info:
  title: HTTPBin
  version: 0.1.0
paths:
  /get:
    get:
      responses:
        '200':
          content:
            application/json:
              example:
                something: that is not found in response

$ dredd httpbin-failure.yaml  https://httpbin.org/
info: Beginning Dredd testing...
info: Found Hookfiles:
fail: GET (200) /get duration: 605ms
info: Displaying failed tests...
fail: GET (200) /get duration: 605ms
fail: body: At '/something' Missing required property: something

request:
method: GET
uri: /get
body:



expected:
headers:
    Content-Type: application/json

body:
{
  "something": "else"
}
statusCode: 200


actual:
statusCode: 200

bodyEncoding: utf-8
body:
{
  "args": {},
  "headers": {
    "Connection": "close",
    "Host": "httpbin.org",
    "User-Agent": "Dredd/0.0.0-semantically-released (Darwin 18.2.0; x64)"
  },
  "origin": "81.109.249.166",
  "url": "https://httpbin.org/get"
}



complete: 0 passing, 1 failing, 0 errors, 0 skipped, 1 total
complete: Tests took 609ms

[kurko]

Can I suggest a checklist in the description so we can follow along how far we've got and how long we still have to go?

[gap777]

A checklist would be helpful to understand better the work done, the work remaining, and the status of the OpenAPI3 support.