I was under the incorrect impression that net/url did not support HTTP 1.1. 
I suspect I stumbled upon some out of date information on stackoverflow. 
Thanks for pointing me in the right direction. Using net/url, net/cookies, 
and json, I hacked the following code (please be gentle, it is literally 
the first lines of Racket I've ever written). There are two key problems 
with this code:

   1. Because cookies handling is not part of net/url, my use of 
   get-pure-port/headers is not able to see cookies, and thus save them, in 
   any of the 3xx redirect responses.
   2. I need a post-pure-port/headers equivalent, so I can post data and 
   reuse the connection. It looks like you can only reuse connections in 
   net/url with only get-pure-port/headers.

Am I missing any other libraries out there?

#lang racket

(require json

(define (get-json-request url #:connection conn)
  (define req-headers
    (let ([cookies (cookie-header url)])
      (cond [(false? cookies) '()]
            [else (list (format "Cookie: ~a" cookies))])))
  (display (format "Headers sent were:\n ~a\n" req-headers))
    (in-port resp-headers)
    (get-pure-port/headers url req-headers #:connection conn #:redirections 
  (extract-and-save-cookies! (map string->bytes/utf-8 (string-split 
resp-headers "\r\n")) url)
  (display (format "\nReceived headers were:\n ~a" resp-headers))
  (read-json in-port))

;; Start a session
(define conn (make-http-connection))

;; Make a request that will force server to set cookies
(displayln (jsexpr->string
             #:connection conn)))

;; Make another request to see what cookies we sent server
(displayln "\n--------------------------------------\n")
(displayln (jsexpr->string
             (string->url "https://postman-echo.com/cookies";)
             #:connection conn)))

;; Close session
(http-connection-close conn)


On Sunday, May 17, 2020 at 4:44:32 AM UTC-5, evdubs wrote:
> Have you taken a look at net/url 
> <https://docs.racket-lang.org/net/url.html?q=net%2Furl>? From there, I 
> see:
>    - make-http-connection 
> <https://docs.racket-lang.org/net/url.html?q=net%2Furl#%28def._%28%28lib._net%2Furl..rkt%29._make-http-connection%29%29>,
>    which can allow calls to get-pure-port/headers to stay connected if 
>    the server allows it.
>    - current-proxy-servers 
> <https://docs.racket-lang.org/net/url.html?q=net%2Furl#%28def._%28%28lib._net%2Furl..rkt%29._current-proxy-servers%29%29>
>    and current-no-proxy-servers, which show they respect http_proxy, 
>    https_proxy, and no_proxy.
> There are also get-pure-port 
> <https://docs.racket-lang.org/net/url.html?q=net%2Furl#%28def._%28%28lib._net%2Furl..rkt%29._get-pure-port%2Fheaders%29%29>
> related functions that allow setting headers, which I think should let you 
> set your cookies? For JSON, you can take look at the json 
> <https://docs.racket-lang.org/json/index.html?q=json> docs if you're 
> interested in converting the HTTP response bodies into a JSON expression. 
> These expressions can then be treated like any other expression where you 
> can map/filter/fold over lists and access map elements with hash table 
> functions.
> To find this stuff, I just searched for "http" and "json" using the ". . . 
> search manuals . . ." box at the top right of the docs. The search looks 
> through all of the Racket API as well as many user-contributed packages. It 
> makes it very easy to find whatever you might be interested in.
> Evan
> On Saturday, May 16, 2020 at 7:45:08 AM UTC-10, fixpoint wrote:
>> I'm on the search for a new programming language to learn, so I thought 
>> I'd check out Racket, but I'm having a hard time trying to do a very common 
>> task that would make Racket practical for my use at work:
>>    - Make a series of HTTP requests to an API that returns JSON responses
>>    - Reuse the HTTP connection to avoid creating new TCP connections for 
>>    each request
>>    - Honors the `http_proxy`, `https_proxy`, and `no_proxy` environment 
>>    variables
>>    - Maintains a "session" where cookies set by the server are sent back 
>>    in subsequent requests
>> My daily driver is Python, so I'm used to its `requests` library. Go and 
>> Rust have similar libraries. While I don't mind piecing some of this 
>> together, I'm struggling as a new user to figure out what libraries are 
>> recommended and, more importantly, how to put them together to accomplish 
>> the above points.
>> Thank you.
>> p.s. The Racket documentation is by far the best looking documentation 
>> I've read in any language. It's quite amazing!

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