How to define an optional parameter in path using swagger

Question

There is a function in my REST web service working with GET method and it has two optional parameters.

I tried to define it in Swagger but I encountered an error, Not a valid parameter definition, after I set the required as false.

I found out that if I set the required value as true the error will be gone. Here is a sample of my Swagger code.

...
paths:
  '/get/{param1}/{param2}':
    get:
      ...
      parameters:
      - name: param1
        in: path
        description: 'description regarding param1'
        required: false
        type: string
      - name: param2
        in: path
        description: 'description regarding param2'
        required: false
        type: string

I didn't experience this with parameters in body or the the ones in query. I think this problem is only related to parameters in path. I could not find any solution in swagger specification files either.

Is there any other way to define optional parameters in Swagger or do I have any mistake in my code?

Any help would be appreciated.

Answer 1

Given that path parameter must be required according to the OpenAPI/Swagger spec, you can consider adding 2 separate endpoints with the following paths:

• /get/{param1}/{param2} when param2 is provided
• /get/{param1}/ when param2 is not provided

Answer 2

It it likely blowing up because you cannot have a base uri parameter optional, only query string values (in the case of a url).

For example:

• GET /products/{id}/pricing?foo=bar
• ** If foo is optional then your IN parameter needs to be "query" not "path"
• ** If {id} is optional then something is wrong. {id} can't be optional because it is contained within the base uri.

This should work:

{
"in":"query",
"required":false
}

This should not work

{
"in":"path",
"required":false
}

change your "in" property to be "query" instead of "path" and it should work.