http-sh

Overview

GET: Hello world

$ http-sh :5000 -- echo Hello world
$ curl -s localhost:5000
Hello world

POST: echo

$ http-sh :5000 -- cat
$ curl -s -d Hai localhost:5000
Hai

Request metadata

The Request metadata is available as JSON on file descriptor 3.

Pairs well with jq

$ http-sh :5000 -- bash -c 'jq <&3'
$ curl -s localhost:5000
{
  "headers": {
    "accept": "*/*",
    "host": "localhost:5000",
    "user-agent": "curl/7.79.1"
  },
  "method": "GET",
  "path": "/",
  "proto": "HTTP/1.1",
  "query": {},
  "remote_ip": "127.0.0.1",
  "remote_port": 51435,
  "request_id": "0391ND23LWW4KVCZ00G30BZAG",
  "uri": "/"
}

$ http-sh :5000 -- bash -c 'echo hello: $(jq -r .path <&3)'
$ curl -s localhost:5000/yello
hello: /yello

Response metadata

You can set the Response metadata by writing JSON on file descriptor 4. Currently you can set the Response status and headers.

Pairs well with jo

$ http-sh :5000 -- bash -c 'jo status=404 >&4; echo sorry, eh'
$ curl -si localhost:5000
HTTP/1.1 404 Not Found
content-type: text/plain
transfer-encoding: chunked
date: Sat, 25 Feb 2023 05:20:48 GMT

sorry, eh

Note, for streaming responses, you'll want to close fd 4, so the Response is initiated.

$ http-sh :5000 -- bash -c 'exec 4>&-; while true ; do date; sleep 1; done'
$ curl -s localhost:5000
Sat Feb 25 00:31:41 EST 2023
Sat Feb 25 00:31:43 EST 2023
Sat Feb 25 00:31:44 EST 2023
Sat Feb 25 00:31:45 EST 2023
Sat Feb 25 00:31:46 EST 2023
...

server-sent events

Pairs well with xcat

$ http-sh :5000 -- bash -c '
    jo headers="$(jo "content-type"="text/event-stream")" >&4
    exec 4>&-
    tail -F source.json | xcat -- bash -c "sed '\''s/^/data: /g'\''; echo;"
'

# simulate generating events in a seperate process
$ while true; do jo date="$(date)" ; sleep 1 ; done >> source.json

$ curl -si localhost:5000/
HTTP/1.1 200 OK
content-type: text/event-stream
transfer-encoding: chunked
date: Sat, 25 Feb 2023 18:13:37 GMT

data: {"date":"Sat Feb 25 13:13:35 EST 2023"}

data: {"date":"Sat Feb 25 13:13:36 EST 2023"}

data: {"date":"Sat Feb 25 13:13:37 EST 2023"}

data: {"date":"Sat Feb 25 13:13:38 EST 2023"}

data: {"date":"Sat Feb 25 13:13:39 EST 2023"}

...

Direct Testing of Script

While http-sh provides a convenient way to serve HTTP requests and interact with the associated metadata, there might be times when you wish to directly test the script you intend to use with http-sh without the HTTP layer.

To simulate the environment in which http-sh invokes your script, you can use the following command:

echo "Hai" | ./root.sh 3</tmp/req.json 4>&1

Here's a breakdown of what's happening:

1. echo "Hai": Simulates sending the request body.
2. ./root.sh: Your script that processes the input.
3. 3</tmp/req.json: Mimics the JSON metadata that http-sh provides on file descriptor 3. To obtain this JSON metadata for testing, check the log line of a specific request from the http-sh logs, which are structured in JSON format.
4. 4>&1: Redirects output from file descriptor 4 to stdout, so you can see the response metadata and main response together in the terminal.

This method allows you to bypass http-sh during development and testing phases, ensuring that your script behaves as expected before integrating it with the HTTP server.