I got it to work! I believe akkartik was right. Using command (-c) did the trick, which I assume ensured disconnecting from the database.

  (system "psql -U root -d root -c 'SELECT * FROM items'")

  item_id | name | type | description | created | location ---------+--------+------+-------------------------------------+----------------------------+---------------------------------------------------- 1 | marble | tool | A small, translucent orange bauble. | 2022-02-23 17:59:45.480545 | 0101000020E610000012C2A38D239A5EC040683D7C99E44240 (1 row)

btw I caught a misspelled 'password' in postgresql-secure-connect:

  (mac postgresql-secure-connect (user db ssl-protocol (o passowrd nil))

  (= dbconn (postgresql-connect "root" "root" password))
  (table-exists? dbconn "items")

It's a new project. However, Hubski has been using postgres for a few years, but it's currently an amalgam of Arc and Racket. I didn't write the db code, and am trying to start fresh. The Hubski racket connection looks like:

  (define db-conn
  (virtual-connection
   (connection-pool
    (lambda () (postgresql-connect
           #:user db-user
           #:password db-pass
           #:database db-database
           #:server db-server
           )))))

  (define db-user     "user")
  (define db-pass     "password")
  (define db-database "hubski")
  (define db-server   "localhost")

Here's my test code that works in the command line, and the response. (I named my db "root" atm and will change that and the user once I get it working. I'm running the app as root.):

  arc> (tostring (pipe-to (system "psql -U root -d root") (prn "SELECT * FROM items WHERE name = 'marble';"))                                     )
  " item_id |  name  | type |             description             |          created           |                                                           
  location                      \n---------+--------+------+-------------------------------------+--                                     ------------ 
  --------------+----------------------------------------------------\n       1 | marble | tool | A small, translucent orange bauble. | 2022-02-23 
  17:59:45.480545 | 0101000020E610000012C2A38D239A5EC040683D7C99E44240\n(1 row)\n\n"
  arc>

I even tried to specify the host and port:

  (pipe-to (system "psql -U root -h 159.203.186.97 -p 5432 -d root") (prn "SELECT * FROM items WHERE name = 'marble';"))

  host    all             root            159.203.186.97:5432      trust

  root@Xyrth:/home/xapp# netstat -tulnp | grep 5432
  tcp        0      0 159.203.186.97:5432     0.0.0.0:*               LISTEN      124232/postgres

BTW, I am using the domain xyrth.com with a nginx reverse proxy. I just had the thought it may be my nginx configuration. It probably needs to listen explicity on 5432? Here's my current sites-enabled:

  server {
    listen 80;
    server_name xyrth.com;
    return 301 https://xyrth.com$request_uri;
  }

  server {
    	listen              443 ssl;
    	server_name         xyrth.com;
        ssl_certificate "/etc/letsencrypt/live/xyrth.com/fullchain.pem";
        ssl_certificate_key "/etc/letsencrypt/live/xyrth.com/privkey.pem";
        ssl_session_cache shared:SSL:5m;
        ssl_session_timeout  10m;

        proxy_redirect      off;
        proxy_set_header    X-Real-IP $remote_addr;
        proxy_set_header    X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header    Host $http_host;

        location / {
                proxy_buffers 16 4k;
                proxy_buffer_size 2k;
                proxy_pass http://159.203.186.97:8080;
		proxy_set_header Host xyrth.com;
        }

        location ~* \.(png|jpg|tif|ico|ttf|woff|svg|eot|otf|mp3|ogg|wav)$ {
        root /home/xapp/static;
        expires max;
        }

        location ~ ^/(xyrth.css) {
                root /home/xapp/static;
                expires max;
        }

  }

Maybe it isn't disconnecting?

  (tostring (system "psql -V"))

  psql (PostgreSQL) 12.9 (Ubuntu 12.9-0ubuntu0.20.04.1)

I did. :)

Even so, I think it's also worth considering that libraries also represent learning opportunities for some (like myself). For whatever reason, perhaps because it isn't my core strength, the only approach to programming that I have found to work for me is to continually try to do something. I seem only to be able to truly absorb the finer points when they are encountered in the context of a whole.

how difficult would it be to add open-id, facebook, twitter, g+ integration?

That depends on how integrated you want to get. It's fairly trivial to be able to add a 'like' or '+1' button, but if you want deeper integration, you'd have to be specific about what you want to do. I haven't tried open-id. I'm sure it's doable.

how does hubski distinguish text submissions vs videos and so on? How do I group/categorize all of them?

For videos, it is a matter of identifying the url as a video url, etc. For example with findsubseq, you can pick out if contains "youtube" "youtu.be", etc. Text submissions are those that lack a url, and don't have an empty text field, etc. No quick fix here. news.arc wasn't made to sort them that way, I had to do that.

how do I add tags to submissions or allow admins to add tags?

There are a number of ways you might go about that. I added the tag as an additional story key/value pair. Depending on your tagging structure, you might want to make each tag it's own template, containing the ids of stories carrying that tag.

how do i decrease the karma required to downvote?

I think there is downvote-threshold* in news.arc, -just change the value. I don't use karma or downvotes with Hubski. So I don't have that code anymore. :)

how do i mimic HN's job page, ie: no name of the poster and no comment field- just link and text. How to group all such posts?

Shouldn't be too difficult. Each story could have a 'job' key with a value of nil or t. If it is t, then opt not to show the comment tree, name, etc.

- If I want to start hacking into the news code, is news.arc the only file I start with? I would also like to change the css, make email field compulsory, send email confirmation and so on. If you could show me some direction, it would be very helpful.

- by integration with other services, I mean allowing likes, +1, commenting, log-in etc. I think I will have to look into the code to start understanding this more, so it is related to the above point.

- about identifying video URLs- how would you recommend expanding something like, say a bit.ly link?

- Yes, I haven't done anything with the code yet because it looks a little unfamiliar at this point. But I'd love to.

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