[FIX] Remove premature call on socket close

Project.toml

@@ -1,7 +1,7 @@
 name = "Jedis"
 uuid = "b89ccfe0-2c5f-46f6-b89b-da3e1c2e286f"
 authors = ["Jack Chan <[email protected]>"]
-version = "0.3.0"
+version = "0.3.1"
 
 [deps]
 MbedTLS = "739be429-bea8-5141-9913-cc70e7f3736d"

src/client.jl

@@ -87,20 +87,20 @@ function Client(; host="127.0.0.1", port=6379, database=0, password="", username
         keepalive_delay
     )
 
-    prepare(client)
+    prepare!(client)
     return client
 end
 
 """
-    prepare(client::Client)
+    prepare!(client::Client)
 
 Prepares a new client, involves pre-pinging the server, logging in with the correct username
 and password, selecting the chosen database, and setting keepalive if applicable.
 
 Pinging the server is to test connection and set socket status to Base.StatusPaused (i.e. a ready state).
 Raw execution is used to bypass locks and retries
 """
-function prepare(client::Client)
+function prepare!(client::Client)
     write(client.socket, resp(["PING"]))
     recv(client.socket)
 
@@ -238,7 +238,7 @@ Reconnects the input client socket connection.
 function reconnect!(client::Client)
     disconnect!(client)
     client.socket = isnothing(client.ssl_config) ? connect(client.host, client.port) : ssl_connect(connect(client.host, client.port), client.host, client.ssl_config)
-    prepare(client)
+    prepare!(client)
     return client
 end
 

src/stream.jl

@@ -21,7 +21,85 @@ Returns non-zero if the handle is active, zero if it’s inactive. Is active whe
 something that involves i/o, like reading, writing, connecting, accepting new connections, etc.
 """
 isactive(socket::TCPSocket) = ccall(:uv_is_active, Cint, (Ptr{Cvoid},), socket.handle)
-
+
+"""
+    netstat(port::Int)::Vector
+
+Calls CLI tool `netstat` to get TCP connection statistics over a specific port.
+Returns a vector os lines, each line represents (Proto, Recv-Q, Send-Q, Local Address, Foreign Address, state).
+"""
+function netstat(port::Int)::Vector
+    try
+        return [split(line) for line in readlines(pipeline(`netstat -na`, `grep $port`))]
+    catch
+        # Catches null pipeline
+    end
+    return
+end
+
+"""
+    tcpstate(src_host::String, src_port::Int, dst_host::String, dst_port::Int)
+
+Returns the TCP state given source and destination host and ports.
+"""
+function tcpstate(src_host::String, src_port::Int, dst_host::String, dst_port::Int)
+    stats = netstat(src_port)
+    isempty(stats) && return
+    for (_, _, _, src_addr, dst_addr, state) in stats
+        if (
+            occursin(src_host, src_addr) &&
+            occursin(string(src_port), src_addr) &&
+            occursin(dst_host, dst_addr) &&
+            occursin(string(dst_port), dst_addr)
+        )
+            return state
+        end
+    end
+    return
+end
+
+"""
+    tcpstate(socket::TCPSocket)
+
+Returns TCP state given a socket object.
+"""
+function tcpstate(socket::TCPSocket)
+    src_host, src_port = hostport(socket)
+    dst_host, dst_port = peerhostport(socket)
+    return tcpstate(src_host, src_port, dst_host, dst_port)
+end
+
+"""
+    hostport(socket::TCPSocket)
+
+Returns host and port given a socket object.
+"""
+function hostport(socket::TCPSocket)
+    host, port = getsockname(socket)
+    return string(host), Int(port)
+end
+
+"""
+    hostport(socket::TCPSocket)
+
+Returns host and port for a peer given a socket object.
+"""
+function peerhostport(socket::TCPSocket)
+    host, port = getpeername(socket)
+    return string(host), Int(port)
+end
+
+"""
+    tryclose(socket::TCPSocket)
+
+Closes a TCP socket connection if the TCP state is `CLOSE_WAIT`.
+"""
+function tryclose(socket::TCPSocket)
+    if isactive(socket) == 0 tcpstate(socket) == "CLOSE_WAIT"
+        close(socket)
+    end
+end
+
 """
     _uv_readcb(handle::Ptr{Cvoid}, nread::Cssize_t, buf::Ptr{Cvoid})
 
@@ -83,8 +161,10 @@ function _uv_readcb(handle::Ptr{Cvoid}, nread::Cssize_t, buf::Ptr{Cvoid})
 
 
             # Line added to close socket when server connection breaks
+            # Closes the connection if the TCP state is CLOSE_WAIT
             # Must be called asynchronously
-            @async begin isactive(stream) == 0 && close(stream) end
+            # TODO: Differentiate UV_ENOBUFS event with server close event
+            # @async tryclose(stream)
         end
         nothing
     end