Re: Why Emacs shows ^M at the end of some lines in sh code blocks that use curl?

[Rodrigo Morales <rodrigo-mailing-lists@morales.pe>]

Bruno Barbier <brubar.cs@gmail.com> writes:

> it's not related to Org (HTTP headers use '\r\n', your JSON

Thanks for pointing me in the right direction. I searched related
information on the Internet and I found out there is an specific section
in Request for Comments (RFC2616) that explicitly states that '\r\n'
should be used as the line break for HTTP headers. I learned this from
https://stackoverflow.com/a/5757349

> You could include a translation step. For example, using 'tr':
>
>    #+begin_src shell :results raw
>      curl --include --silent https://filesampleshub.com/download/code/json/sample1.json | tr -d '\r'
>    #+end_src
>
> If you are fetching arbitrary data, you do not want to do that though.
> You may ask curl to dump the headers in a file, and translate only
> that file (using --dump-header).

I agree with you on not using tr -d '\r' for both the response body and
the response headers. Starting from now, when I feel the need to show
the response headers in my notes, I'll dump the headers to a file and
then show pass that file to 'tr' as shown below:

#+begin_src sh
curl --dump-header /tmp/curl-header.txt --silent --request GET 'https://filesampleshub.com/download/code/json/sample1.json'
echo '----'
cat /tmp/curl-header.txt | tr -d '\r'
#+end_src

#+RESULTS:
#+begin_example
{
    "fear": "quiet",
    "chest": -1477429467,
    "how": false,
    "graph": false,
    "camp": 929234312,
    "plural": "settle"
  }----
HTTP/2 200 
accept-ranges: bytes
access-control-allow-origin: *
age: 3641498
cache-control: public, max-age=0, must-revalidate
content-disposition: inline; filename="sample1.json"
content-type: application/json; charset=utf-8
date: Fri, 18 Oct 2024 22:43:39 GMT
etag: "c4b4a9669841a9ab437f5dce6c9c9230"
last-modified: Fri, 06 Sep 2024 19:12:01 GMT
server: Vercel
strict-transport-security: max-age=63072000
x-matched-path: /download/code/json/sample1.json
x-vercel-cache: HIT
x-vercel-id: gru1::9cdc6-1729291419743-bcee78204a79
content-length: 136

#+end_example

Sometimes when I want to focus on the behavior of an API and don't write
such long command due to that technical detail, I could simply use
restclient. See example below (in my system, the header lines shown by
restclient don't show the ^M character)

#+begin_src restclient
GET https://filesampleshub.com/download/code/json/sample1.json
#+end_src

#+RESULTS:
#+BEGIN_SRC js
{
  "fear": "quiet",
  "chest": -1477429467,
  "how": false,
  "graph": false,
  "camp": 929234312,
  "plural": "settle"
}
// GET https://filesampleshub.com/download/code/json/sample1.json
// HTTP/1.1 200 OK
// Accept-Ranges: bytes
// Access-Control-Allow-Origin: *
// Age: 3641582
// Cache-Control: public, max-age=0, must-revalidate
// Content-Disposition: inline; filename="sample1.json"
// Content-Length: 136
// Content-Type: application/json; charset=utf-8
// Date: Fri, 18 Oct 2024 22:45:03 GMT
// Etag: "c4b4a9669841a9ab437f5dce6c9c9230"
// Last-Modified: Fri, 06 Sep 2024 19:12:01 GMT
// Server: Vercel
// Strict-Transport-Security: max-age=63072000
// X-Matched-Path: /download/code/json/sample1.json
// X-Vercel-Cache: HIT
// X-Vercel-Id: gru1::4ktmb-1729291503557-396fe6c0ce31
// Request duration: 0.258368s
#+END_SRC