lua-resty-sse

Lua Server Side Events client cosocket driver for OpenResty.

Synopsis:

    location /sse_proxy {
      lua_check_client_abort on;
      content_by_lua_block {
        local sse = require("sse")
    
        local function my_cleanup()
          -- need config lua_check_client_abort on;
          ngx.log(ngx.NOTICE, "onabort exit 499")
          ngx.exit(499)
        end
    
        local ok, err0 = ngx.on_abort(my_cleanup)
        if not ok then
          ngx.log(ngx.ERR, "failed to register the on_abort callback: ", err0)
        end
    
        local conn, err = sse.new()
        if not conn then
          ngx.log(ngx.ERR, "failed to get connection: ", err)
          return
        end
        --conn:set_timeout(50000)
        local path = 'http://127.0.0.1:8080/events/123'
    
        local res, err2, is_sse_resp = conn:request_uri(path, {
          ssl_verify = false
        })
        if not res then
          ngx.log(ngx.ERR, "failed to request: ", err2)
          return
        end
    
        conn:transfer_encoding_is_chunked() --process Transfer-Encoding:chunked
        for k, v in pairs(res.headers) do
          ngx.header[k] = v
        end
    
        while is_sse_resp
        do
          local event, err3 = conn:receive()
          if err3 then
            ngx.log(ngx.ERR, "sse request over" .. err3)
            return ngx.exit(ngx.HTTP_OK)
          end
          if event then
            ngx.log(ngx.NOTICE, "sse received success, event=" .. event)
            ngx.print(event)
            ngx.flush()   -- must flush
          end
        end
        ngx.say(res.body)
        return ngx.exit(ngx.status)
      }
    }