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9087 :: jsFetch fetch

• domogled (orginal) [2022-04-07T00:52:31+02:00] view original

  Hello,

  I am experimenting with js fetch API in Nim language (devel, jsfetch is experimental).

  proc ajaxOptions(metoda: HttpMethod = HttpGet): FetchOptions =
    
    let headers = newHeaders()
    headers.add("key", "value")
    
    result = newFetchOptions(
      metod =  metoda,
      mode = fmNoCors,
      cache = fchNoCache,
      credentials = fcOmit,
      headers = headers,
      redirect = frFollow,
      referrerPolicy = frpNoReferrer,
      body = "".cstring,
      keepalive = false
      
      # referrer = "client".cstring,
      # integrity = "".cstring
    )
  
  
  
  proc ajaxGet*(url: cstring):Future[Response] {.async.} =
    
    result = url.fetch ajaxOptions(metoda = HttpGet)
  
  
  
  
  proc ajaxPost*(url: cstring):Future[Response] {.async.} =
    
    # result = url.fetch ajaxOptions(metoda = HttpPost)
    
    let options = ajaxOptions(metoda = HttpPost)
    
    result = url.fetch options
  
  
  
  
  Run

  When I call fetch without FetchOptions parameter, url.fetch() the query works well.

  When I add options fetch(url, options), there is an error running compiled javascript.

  
  Uncaught (in promise) TypeError: Window.fetch: 'headers' member of RequestInit could not be converted to any of: sequence<sequence<ByteString>>, record<ByteString, ByteString>.
      ajaxPost_1224736842 http://localhost:8081/wedos/app.js:5016
      example_822083600 http://localhost:8081/wedos/app.js:5085
      onLoad_822083597 http://localhost:8081/wedos/app.js:5145
      EventListener.handleEvent* http://localhost:8081/wedos/app.js:5157
  app.js:5016:25
      example_822083600 http://localhost:8081/wedos/app.js:5131
      AsyncFunctionThrow self-hosted:642
      (Async: async)
      onLoad_822083597 http://localhost:8081/wedos/app.js:5145
      (Async: EventListener.handleEvent)
      <anonymous> http://localhost:8081/wedos/app.js:5157
  Run

  Where is the problem?

  thanks

  Petr Živoslav Bolf

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• domogled (orginal) [2022-04-12T09:54:47+02:00] view original

  Solved. I think, that is it bug in js compiler.

  result.headers is null. I I add result.headers = headers, its work.

  proc ajaxOptions(metoda: HttpMethod = HttpGet): FetchOptions =
    
    let headers = newHeaders()
    headers.add("key", "value")
    
    result = newFetchOptions(
      metod =  metoda,
      mode = fmNoCors,
      cache = fchNoCache,
      credentials = fcOmit,
      headers = headers,
      redirect = frFollow,
      referrerPolicy = frpNoReferrer,
      body = "".cstring,
      keepalive = false
      
      # referrer = "client".cstring,
      # integrity = "".cstring
    )
  # if I add this line, it works and return headers with correct value
  result.headers = headers
  
  
  
  Run

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• z_____________ (orginal) [2022-04-12T12:42:13+02:00] view original

  Looks to me like an unintentional omission in std/jsfetch:

  func newfetchOptions*(metod: HttpMethod; body: cstring;
      mode: FetchModes; credentials: FetchCredentials; cache: FetchCaches; referrerPolicy: FetchReferrerPolicies;
      keepalive: bool; redirect = frFollow; referrer = "client".cstring; integrity = "".cstring,
      headers: Headers = newHeaders()): FetchOptions =
    ## Constructor for `FetchOptions`.
    result = FetchOptions(
      body: body, mode: cstring($mode), credentials: cstring($credentials), cache: cstring($cache), referrerPolicy: cstring($referrerPolicy),
      keepalive: keepalive, redirect: cstring($redirect), referrer: referrer, integrity: integrity,
      metod: (case metod
        of HttpHead:   "HEAD".cstring
        of HttpGet:    "GET".cstring
        of HttpPost:   "POST".cstring
        of HttpPut:    "PUT".cstring
        of HttpDelete: "DELETE".cstring
        of HttpPatch:  "PATCH".cstring
        else:          "GET".cstring
      )
    )
  Run

  newfetchOptions takes headers as a parameter but doesn't use it when initializing FetchOptions.

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