Array query parameter

[javier-sierra-sngular]

What happened?

The query parameter of type array is not transformed into an array in the request URL.
[GET] /?singleParameter=true&arrayParameter=true - Incorrect
[GET] /?singleParameter=true&arrayParameter[]=true - Correct

What did you expect to happen?

If the value is of type array, the URL should contains the appropiate syntax to indicate it.

Version

2.7.2

Environment

Node v18.18.0

How can we reproduce this bug?

Using this workflow will result in the request [GET] /?singleParameter=true&arrayParameter=true, where arrayParameter is not an array as specified in the workflow

version: "1.0"
name: My API
config:
  http:
    baseURL: http://localhost:1235
tests:
  default:
    name: Default
    steps:
      - http:
          url: /
          method: GET
          params:
            singleParameter: false
            arrayParameter:
              - true
          check:
            status: 0

Relevant log output

No response

Would you be interested in working on a bugfix for this issue?

• Yes! Assign me

[javier-sierra-sngular]

/filter?fruits=apple&fruits=banana

It is a bit strange because the same workflow you have provided results me in different output than yours:
/filter?fruits=apple%2Cbanana.

This is usually interpreted as single string apple,banana rather than an array of two elements.

This is the complete workflow I used for this test

version: '1.0'
name: My API
config:
  http:
    baseURL: http://localhost:1235
tests:
  default:
    name: Default
    steps:
      - http:
          url: /filter
          method: GET
          params:
            fruits:
              - apple
              - banana
          check:
            status: 0

And Step CI version is 2.7.2

[javier-sierra-sngular]

The main problem is when you specify a single element array.

The fact is when a workflow is built using a single array parameter, Step CI make the request and the resulting URL may cause validation errors in the API. Because it is waiting for an array but a single string value is received.

I know there are many ways to represent arrays in a query string and some of them are ambiguous when there are a single element only.

This is an example of how express.js parse url query parameters

/filter?fruits=apple%2Cbanana
{ fruits: 'apple,banana' } // single string :S, this is related to previous comment

/filter?fruits=apple&fruits=banana
{ fruits: [ 'apple', 'banana' ] } // ok when 2+ elements

/filter?fruits=apple
{ fruits: 'apple' } // it is not a single element array

/filter?fruits[]=apple    // this is the best representation IMHO
{ fruits: [ 'apple' ] } 

I debugged the application and I see that the parameter searchString is passed as URLSearchParams to got library. I tested URLSearchParams.toString() and it returns the values separated by comma. I wonder if here is the problem.
I also tested to replace URLSearchParams by custom string 'fruits[]=apple' and it worked like a charm. (src/index.ts:730)

This point to the possible solution commented here sindresorhus/got#1559 (comment) to use like /filter?fruits[]=apple representation
You could also use https://github.com/sindresorhus/query-string and just pass the stringified query parameters to searchParams.

Ps. you can still define it manually, no need to use the params shortcut

I am not writing the workflow manually, it is generated by plugin-openapi that uses params

[mishushakov]

Would you be able to contribute a fix?

[javier-sierra-sngular]

Sure, I will work in a PR

[mishushakov]

My example above was incorrect

http:
  url: /filter
  method: GET
  params:
    fruits:
      - apple
      - banana  

produces:

/filter?fruits=apple%2Cbanana

while this:

http:
  url: /filter
  method: GET
  params:
    -
      - 'fruits'
      - 'apple'
    -
      - 'fruits'
      - 'banana'

produces:

/filter?fruits=apple&fruits=banana

[mishushakov]

Here's a less weirder way to express the above

params:
  - ['fruits', 'apples']
  - ['fruits', 'bananas']

[mishushakov]

Will reopen it as the issue still exists

[alenaksu]

My two cents: I don't think the syntax 'parameter[]' should be considered correct because it is not a standard syntax. Instead, it's just a common way to represent arrays. Even though it is natively supported by some languages/frameworks, like PHP, it doesn't necessarily mean that every framework follows this convention.

I believe a better way to handle this would be to explicitly add the brackets in the parameter name in the YAML.

So, following the example @mishushakov provided, it may look like this:

params:
  - ['fruits[]', 'apples']
  - ['fruits[]', 'bananas']

[mishushakov]

Agree with @alenaksu fully. Moved to discussions for now

[RemiBardon]

I agree with @alenaksu, the [] are non-standard and query params should be repeated. @javier-sierra-sngular It's up to your server's parser to map it to an array if you ask it to.

[RemiBardon]

However I also agree with @javier-sierra-sngular in saying that /filter?fruits=apple%2Cbanana is non-standard. It should be /filter?fruits=apple&fruits=banana.

[mishushakov]

From what I have seen, /filter?fruits=apple,banana is the most common, not the other ones.

[RemiBardon]

I agree it's common, but it's not standard. IMO Step CI shouldn't make this assumption and stick to standards. If you want you can add a config flag, but default behavior shouldn't be opinionated.

[mishushakov]

Whatever is the standard should be the standard in Step CI 👍