rust-echo-server

Usage

docker run --rm --init -p 3000:3000 -e RUST_LOG=debug sstc/echo-server

Api

System api

All system api are prefix with /_/

curl localhost:3000/_/version # Server version

curl localhost:3000/_/foo # Unknown api would response 404

Echo api

• It would echo request body if request without prefix of system api (works with all http verbs, except OPTIONS and HEAD).

  curl -v localhost:3000/foo -d '{"a":123}'

  ...
  * Connection #0 to host localhost left intact
  {"a":123}

• It would response the requested status by the header x-echo-status.

  curl -v localhost:3000/foo -H "x-echo-status: 400"

  * Connected to localhost (127.0.0.1) port 3000 (#0)
  > GET /foo HTTP/1.1
  > Host: localhost:3000
  > User-Agent: curl/7.81.0
  > Accept: */*
  > x-echo-status: 400
  > 
  * Mark bundle as not supporting multiuse
  < HTTP/1.1 400 Bad Request
  < content-length: 0
  < date: Wed, 09 Feb 2022 21:05:23 GMT
  < 
  * Connection #0 to host localhost left intact

• It would response 400 and x-echo-status-error if header x-echo-status is invalid.

  curl -v localhost:3000/foo -H "x-echo-status: bar"

  ...
  > x-echo-status: bar
  ...
  
  ...
  < HTTP/1.1 400 Bad Request
  < x-echo-status-error: invalid digit found in string
  ...

• It would response content-type if request path with extension name.

  curl -v localhost:3000/foo.json -d '{"a":123}'

  ...
  < content-type: application/json
  ...

Exceptions

• The OPTIONS (preflight) handle CORS (won't echo).

  curl -v localhost:3000/foo \
    -XOPTIONS \
    -H "Origin: http://foo.bar" \
    -H "Access-Control-Request-Method: FOOMETHOD" \
    -H "Access-Control-Request-Headers: BAR"

  * Connected to localhost (127.0.0.1) port 3000 (#0)
  > OPTIONS /foo HTTP/1.1
  > Host: localhost:3000
  > User-Agent: curl/7.81.0
  > Accept: */*
  > Origin: http://foo.bar
  > Access-Control-Request-Method: FOOMETHOD
  > Access-Control-Request-Headers: BAR
  > 
  * Mark bundle as not supporting multiuse
  < HTTP/1.1 200 OK
  < access-control-allow-origin: http://foo.bar
  < access-control-allow-methods: FOOMETHOD
  < access-control-allow-headers: BAR
  < content-length: 0
  < date: Wed, 09 Feb 2022 21:02:17 GMT
  < 
  * Connection #0 to host localhost left intact

• The HEAD (body-less) would response with empty body (won't echo).

  curl -v localhost:3000/foo \
    -XHEAD \
    -d '{"a":123}'

  * Connected to localhost (127.0.0.1) port 3000 (#0)
  > HEAD /foo HTTP/1.1
  > Host: localhost:3000
  > User-Agent: curl/7.64.0
  > Accept: */*
  > Content-Length: 9
  > Content-Type: application/x-www-form-urlencoded
  >
  * upload completely sent off: 9 out of 9 bytes
  < HTTP/1.1 200 OK
  < content-length: 0
  < date: Sat, 16 Feb 2019 08:20:28 GMT
  <
  * Connection #0 to host localhost left intact

Dev memo

RUST_LOG="debug" cargo watch -x run -w src

Bump version

• cargo bump patch
• Commit and push

About

The chinese translation of this app is "複讀機" （meme)

Why? It's human nature.

因為這是人類本質。