I test my Api with DREDD against it's specification (written in Openapi3 considering, painfull limitations of Support by Dredd considered). No I have one endpoint, which produces CSV-data if the Accept-header is set so.
'/my-endpoint':
summary: ...
description: ...
get:
# parameters:
# -
# in: header
# name: Accept
# description: "Response format: application/json or text/csv"
# example: "text/csv"
responses:
'200':
description: ...
content:
text/csv:
schema:
type: string
example:
summary: 'csv table'
value: 'cell1, cell2'
When I run the test with Dredd the test fails with
expected:
headers:
body:
[
{
"key": "summary",
"value": "csv table"
},
{
"key": "value",
"value": "cell1, cell2"
}
]
statusCode: 200
Clearly there is something misunderstood and Dredd expects still JSON. Also the API is not told to produce the CSV Version. If I commit in the Accept header in the code abvoe I get the very same result - the expecetd result above and as actual result the JSON version of the my-endpoint-data and also ad warning:
warn: API description parser warning in .../tmp/transformed.specs.yml: 'Parameter Object' 'name' in location 'header' should not be 'Accept', 'Content-Type' or 'Authorization'
I read here and here: Header parameters named Accept, Content-Type and Authorization are not allowed. To describe these headers, use the corresponding OpenAPI keywords - but what are they? According to this and this page it seems to be enough to specify a response of the given type but that is clearly not enough to tell Dredd to produce such a header.
You got an error because the value of the example key is meant to be a literal example value. So in your case it's treated as an object with the summary and value properties.
Change your definition to:
content:
text/csv:
schema:
type: string
example: 'cell1, cell2'
Or if you want to provide a summary/description for an example, use examples instead:
content:
text/csv:
schema:
type: string
examples:
csv table:
summary: A CSV table with 2 cells
value: 'cell1, cell2'