PureBasic

Manually Follow HTTP Redirects

See more HTTP Examples

Demonstrates how to manually follow redirects for an HTTP GET. PureBasic

IncludeFile "CkHttpResponse.pb"
IncludeFile "CkHttp.pb"

Procedure ChilkatExample()

    success.i = 0

    ; This example requires the Chilkat API to have been previously unlocked.
    ; See Global Unlock Sample for sample code.

    http.i = CkHttp::ckCreate()
    If http.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ; The FollowRedirects property controls whether redirects
    ; are automatically followed.  The default behavior is to
    ; automatically follow redirects.

    ; Explicitly set FollowRedirects so that redirects are NOT automatically taken:
    CkHttp::setCkFollowRedirects(http, 0)

    resp.i = CkHttpResponse::ckCreate()
    If resp.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success = CkHttp::ckHttpNoBody(http,"GET","http://yandex.ru/",resp)
    If success = 0
        Debug CkHttp::ckLastErrorText(http)
        CkHttp::ckDispose(http)
        CkHttpResponse::ckDispose(resp)
        ProcedureReturn
    EndIf

    status.i = CkHttpResponse::ckStatusCode(resp)
    Debug "HTTP Response Status: " + Str(status)

    ; The FinalRedirectUrl property will contain the redirect URL
    ; If FollowRedirects was equal to 1, then all of the 
    ; intermediate redirects (if any) would be followed until
    ; there were no more redirects.  However, because 
    ; FollowRedirects is not 1, FinalRedirectUrl contains
    ; the next redirect URL.

    loopCount.i = 0

    While (status = 302)

        Debug "Redirect URL: " + CkHttp::ckFinalRedirectUrl(http)

        nextUrl.s = CkHttp::ckFinalRedirectUrl(http)
        success = CkHttp::ckHttpNoBody(http,"GET",nextUrl,resp)
        If success = 0
            Debug CkHttp::ckLastErrorText(http)
            CkHttp::ckDispose(http)
            CkHttpResponse::ckDispose(resp)
            ProcedureReturn
        EndIf

        status = CkHttpResponse::ckStatusCode(resp)
        Debug "HTTP Response Status: " + Str(status)

        ; For safety, prevent infinite loops by
        ; keeping a loopCount and only allows following a max 
        ; of 10 redirects:
        loopCount = loopCount + 1
        If loopCount > 10
            Debug "Too many redirects."
            CkHttp::ckDispose(http)
            CkHttpResponse::ckDispose(resp)
            ProcedureReturn
        EndIf

    Wend


    CkHttp::ckDispose(http)
    CkHttpResponse::ckDispose(resp)


    ProcedureReturn
EndProcedure