solution: docs for WebSocket support

README.adoc

@@ -24,7 +24,7 @@ It automatically verifies their availability and the current status of the netwo
 
 Provides:
 
-- Standard Bitcoin and Ethereum JSON RPC API
+- Standard Bitcoin and Ethereum JSON RPC API over HTTP and WebSocket
 - Enhanced gRPC-based API, with upstream selection, async execution, etc
 - **Secure** TLS with optional client authentication
 - Blockchain-aware edge **caching**, in memory and Redis
@@ -107,12 +107,12 @@ Which sets the following:
 
 - gRPC access through 0.0.0.0:2449
 ** TLS security is disabled (_please don't use in production!_)
-- JSON RPC access through 0.0.0.0:8545
+- JSON RPC access through 0.0.0.0:8545 (both HTTP and WebsScket)
 ** proxy requests to Ethereum and Kovan upstreams
 ** request path for Ethereum Mainnet is `/eth`, `/kovan` for Kovan Testnet, and `/btc` for bitcoin
 ** i.e. call Ethereum Mainnet by `POST http://127.0.0.0:8545/eth` with JSON RPC payload
 - two upstreams, one for Ethereum Mainnet and another for Kovan Testnet (both upstreams are configured to use Infura endpoint)
-- for Ethereum Mainnet it connects using JSON RPC and Websockets connections,
+- for Ethereum Mainnet it connects using JSON RPC and WebSocket connections,
 - for Bitcoin Mainet only JSON RPC is used
 - `${INFURA_USER}` will be provided through environment variable
 
@@ -146,7 +146,7 @@ Tools such as https://github.com/fullstorydev/grpcurl[gRPCurl] can automatically
 
 Alternatively you can connect to port 8545 with traditional JSON RPC requests
 
-==== Access using JSON RPC
+==== Access using JSON RPC over HTTP
 
 Dshackle implements standard JSON RPC interface, providing additional caching layer, upstream readiness/liveness checks, retry and other features for building Fault Tolerant services.
 
@@ -165,6 +165,24 @@ curl --request POST \
 {"jsonrpc":"2.0","id":1,"result":"0x72fa5e0181"}
 ----
 
+==== Access using JSON RPC over WebSocket
+
+Or the same Proxy URL can be accessed through WebSocket
+
+[source,bash]
+----
+websocat ws://localhost:8545/eth
+----
+
+Then make RPC calls or subscriptions:
+
+----
+> | {"jsonrpc":"2.0", "id": 1, "method": "eth_subscribe", "params": ["newHeads"]}
+
+< | {"jsonrpc":"2.0","id":1,"result":"1f8"}
+< | {"jsonrpc":"2.0","method":"eth_subscription","params":{"result":{....},"subscription":"1f8"}}
+----
+
 ==== Access using gRPC
 
 NOTE: It's not necessary to use gRPC, as Dshackle can provide standard JSON RPC proxy, but Dshackle gRPC interface improves performance and provides additional features.

docs/03-server-config.adoc

@@ -62,6 +62,10 @@ a| `upstreams`
 
 === Enabling JSON RPC proxy
 
+In addition to the gRPC protocol, Dshackle provides access compatible with Bitcoin and Ethereum JSON RPC.
+The same server can be accessible as an HTTP JSON RPC and WebSocket JSON RPC.
+For Ethereum, besides the standard RPC calls, it provides RPC subscriptions with `eth_subscribe` method.
+
 .Example proxy:
 [source,yaml]
 ----
@@ -82,7 +86,9 @@ cluster:
 With that configuration Dshackle starts a JSON RPC proxy:
 
 - JSON RPC server is listening on `0.0.0.0:8080`
-- `http://0.0.0.0:8080/eth` provides access to Ethereum API routed to an available upstream
+- `http://0.0.0.0:8080/eth` (and `ws://0.0.0.0:8080/eth`) provides access to Ethereum API routed to an available upstream
+
+NOTE: Same URL should be used to access both HTTP RPC and WebSocket RPC
 
 .Full configuration:
 [source,yaml]

docs/reference-configuration.adoc

@@ -50,6 +50,7 @@ cache:
 proxy:
   host: 0.0.0.0
   port: 8080
+  websocket: true
   tls:
     enabled: true
     server:
@@ -373,20 +374,26 @@ proxy:
 
 | `host`
 | `127.0.0.0`
-| Host to bind gRPC server
+| Host to bind HTTP server
 
 | `port`
-| `2449`
-| Port to bind gRPC server
+| `8080`
+| Port to bind HTT server
 
+| `websocket`
+| `true`
+| Enable WebSocket Proxy
 
 | `tls`
 |
-| Setup TLS configuration for the Proxy server. See <<tls>> section
+| Setup TLS configuration for the Proxy server.
+See <<tls>> section
 
 | `routes`
 |
-a| Routing paths for Proxy.The proxy will handle requests as `https://${HOST}:${PORT}/${ROUTE_ID}` (or `http://` if TLS is not enabled)
+a| Routing paths for Proxy.
+The proxy will handle requests as `https://${HOST}:${PORT}/${ROUTE_ID}` (or `http://` if TLS is not enabled).
+For WebSocket it's `wss` / `ws`, accordingly.
 |===
 
 .Route config
@@ -663,14 +670,14 @@ rpc:
 ----
 
 | `ws.url`
-| Websocket URL to connect to.
+| WebSocket URL to connect to.
 Optional, but optimizes performance if it's available.
 
 | `ws.origin`
-| HTTP `Origin` if required by Websocket remote server.
+| HTTP `Origin` if required by WebSocket remote server.
 
 | `ws.basic-auth` + ...
-| Websocket Basic Auth configuration, if required by the remote server
+| WebSocket Basic Auth configuration, if required by the remote server
 
 | `ws.frameSize`
 | WebSocket frame size limit.