web-echo

The web-echo service is an immutable JSON data recording service.

This service allows you to easily define on the fly JSON recorders which can be fed by remote services using either the dynamically generated webhook or the websockets URL you've provided. Then, at any time you can check/get what has been sent by the remote services.

The storage implementation is using a blockchain approach to ensure data integrity; when data has been sent to the service, it always provides back a receipt proof.

Quick local start

Use scala-cli to download and start a web-echo service on port 8080 with API documentation on http://127.0.0.1:8080/docs :

scala-cli --dep fr.janalyse::web-echo:2.1.0 -e 'webecho.Main.main(args)'

Quick test

Quick test once the web-service is started and running on port 8080

Testing with webhooks

ENDPOINT=http://127.0.0.1:8080/api/v2
# create a new recorder and get its ID
ID=$(curl -X POST $ENDPOINT/recorder  -H 'accept: application/json' | jq -r .id)

# simulate some data sent by a remote service
curl -s "$ENDPOINT/recorder/$ID?name=joe&age=42"  | jq
curl -s -X PUT $ENDPOINT/recorder/$ID -H 'accept: application/json' -d '{"name":"jane","age":24}' | jq
curl -s -X POST $ENDPOINT/recorder/$ID -H 'accept: application/json' -d '{"name":"john","age":12}' | jq

# then check the recorded content
curl -s "$ENDPOINT/recorder/$ID/records" | jq

Testing with websockets

First, starts a simple websocket server that just send ticks :

scala-cli basic-wss-server.sc -- 8888
# OR
scala-cli https://raw.githubusercontent.com/dacr/web-echo/refs/heads/master/basic-wss-server.sc -- 8888

Then

ENDPOINT=http://127.0.0.1:8080/api/v2

# create a new recorder and get its ID
ID=$(curl -X POST $ENDPOINT/recorder  -H 'accept: application/json' | jq -r .id)

# then register the websocket server to the recorder
curl -s -X POST $ENDPOINT/recorder/$ID/websocket -H 'accept: application/json' -d '{
  "uri": "ws://127.0.0.1:8888",
  "expire": "60 seconds"
}'

# then check the recorded content
curl -s "$ENDPOINT/recorder/$ID/records?limit=10" | jq .data.tick

Configuration

Environment variable	Description	default value
WEB_ECHO_LISTEN_IP	Listening network interface	"0.0.0.0"
WEB_ECHO_LISTEN_PORT	Listening port	8080
WEB_ECHO_PREFIX	Add a prefix to all defined routes	""
WEB_ECHO_URL	How this service is known from outside	"http://127.0.0.1:8080"
WEB_ECHO_STORE_PATH	Where data are stored	"/tmp/web-echo-cache-data"
WEB_ECHO_WEBSOCKETS_DEFAULT_DURATION	Default duration for websockets connection	15m
WEB_ECHO_WEBSOCKETS_MAX_DURATION	Maximum duration for websockets connection	4h
WEB_ECHO_SHA_GOAL	Difficulty level for Proof of Work (0=off)	0