MINOR: filters/lua: Support the HTTP filtering from filters written in lua

Now an HTTPMessage class is available to manipulate HTTP message from a filter
it is possible to bind HTTP filters callback function on lua functions. Thus,
following methods may now be defined by a lua filter:

  * Filter:http_headers(txn, http_msg)
  * Filter:http_payload(txn, http_msg, offset, len)
  * Filter:http_end(txn, http_msg)

http_headers() and http_end() may return one of the constant filter.CONTINUE,
filter.WAIT or filter.ERROR. If nothing is returned, filter.CONTINUE is used as
the default value. On its side, http_payload() may return the amount of data to
forward. If nothing is returned, all incoming data are forwarded.

For now, these functions are not allowed to yield because this interferes with
the filter workflow.

diff --git a/src/hlua.c b/src/hlua.c
index cd539d05f4aa8ca84afb42140ef3b17de758e4c4..be95a97296c97b15b7363215d3960d555a2cacb8 100644 (file)
--- a/src/hlua.c
+++ b/src/hlua.c
@@ -6253,13 +6253,12 @@ __LJMP static int hlua_http_msg_is_eom(lua_State *L)
 __LJMP static int hlua_http_msg_get_in_len(lua_State *L)
 {
        struct http_msg *msg;
-       struct htx *htx;
+       size_t output, input;
 
        MAY_LJMP(check_args(L, 1, "input"));
        msg = MAY_LJMP(hlua_checkhttpmsg(L, 1));
-
-       htx = htxbuf(&msg->chn->buf);
-       lua_pushinteger(L, htx->data - co_data(msg->chn));
+       hlua_http_msg_filter(L, 1, msg, &output, &input);
+       lua_pushinteger(L, input);
        return 1;
 }
 
@@ -6269,11 +6268,12 @@ __LJMP static int hlua_http_msg_get_in_len(lua_State *L)
 __LJMP static int hlua_http_msg_get_out_len(lua_State *L)
 {
        struct http_msg *msg;
+       size_t output, input;
 
        MAY_LJMP(check_args(L, 1, "output"));
        msg = MAY_LJMP(hlua_checkhttpmsg(L, 1));
-
-       lua_pushinteger(L, co_data(msg->chn));
+       hlua_http_msg_filter(L, 1, msg, &output, &input);
+       lua_pushinteger(L, output);
        return 1;
 }
 
@@ -10154,7 +10154,16 @@ static int hlua_filter_callback(struct stream *s, struct filter *filter, const c
                        flt_hlua->nargs++;
                }
                else if (flags & HLUA_FLT_CB_ARG_HTTP_MSG) {
-                       /* XXX: Not implemented yey */
+                       if (dir == SMP_OPT_DIR_REQ)
+                               lua_getfield(flt_hlua->T, -1, "http_req");
+                       else
+                               lua_getfield(flt_hlua->T, -1, "http_res");
+                       if (lua_type(flt_hlua->T, -1) == LUA_TTABLE) {
+                               lua_pushstring(flt_hlua->T, "__filter");
+                               lua_pushlightuserdata(flt_hlua->T, filter);
+                               lua_settable(flt_hlua->T, -3);
+                       }
+                       flt_hlua->nargs++;
                }
 
                /* Check stack size. */
@@ -10257,6 +10266,52 @@ static int  hlua_filter_end_analyze(struct stream *s, struct filter *filter, str
                                    (HLUA_FLT_CB_FINAL | HLUA_FLT_CB_RETVAL | HLUA_FLT_CB_ARG_CHN));
 }
 
+static int  hlua_filter_http_headers(struct stream *s, struct filter *filter, struct http_msg *msg)
+{
+       struct hlua_flt_ctx *flt_ctx = filter->ctx;
+
+       flt_ctx->flags &= ~HLUA_FLT_CTX_FL_PAYLOAD;
+       return hlua_filter_callback(s, filter, "http_headers",
+                                   (!(msg->chn->flags & CF_ISRESP) ? SMP_OPT_DIR_REQ : SMP_OPT_DIR_RES),
+                                   (HLUA_FLT_CB_FINAL | HLUA_FLT_CB_RETVAL | HLUA_FLT_CB_ARG_HTTP_MSG));
+}
+
+static int  hlua_filter_http_payload(struct stream *s, struct filter *filter, struct http_msg *msg,
+                                    unsigned int offset, unsigned int len)
+{
+       struct hlua_flt_ctx *flt_ctx = filter->ctx;
+       struct hlua *flt_hlua;
+       int dir = (!(msg->chn->flags & CF_ISRESP) ? SMP_OPT_DIR_REQ : SMP_OPT_DIR_RES);
+       int idx = (dir == SMP_OPT_DIR_REQ ? 0 : 1);
+       int ret;
+
+       flt_hlua = flt_ctx->hlua[idx];
+       flt_ctx->cur_off[idx] = offset;
+       flt_ctx->cur_len[idx] = len;
+       flt_ctx->flags |= HLUA_FLT_CTX_FL_PAYLOAD;
+       ret = hlua_filter_callback(s, filter, "http_payload", dir, (HLUA_FLT_CB_FINAL | HLUA_FLT_CB_ARG_HTTP_MSG));
+       if (ret != -1) {
+               ret = flt_ctx->cur_len[idx];
+               if (lua_gettop(flt_hlua->T) > 0) {
+                       ret = lua_tointeger(flt_hlua->T, -1);
+                       if (ret > flt_ctx->cur_len[idx])
+                               ret = flt_ctx->cur_len[idx];
+                       lua_settop(flt_hlua->T, 0); /* Empty the stack. */
+               }
+       }
+       return ret;
+}
+
+static int  hlua_filter_http_end(struct stream *s, struct filter *filter, struct http_msg *msg)
+{
+       struct hlua_flt_ctx *flt_ctx = filter->ctx;
+
+       flt_ctx->flags &= ~HLUA_FLT_CTX_FL_PAYLOAD;
+       return hlua_filter_callback(s, filter, "http_end",
+                                   (!(msg->chn->flags & CF_ISRESP) ? SMP_OPT_DIR_REQ : SMP_OPT_DIR_RES),
+                                   (HLUA_FLT_CB_FINAL | HLUA_FLT_CB_RETVAL | HLUA_FLT_CB_ARG_HTTP_MSG));
+}
+
 static int  hlua_filter_tcp_payload(struct stream *s, struct filter *filter, struct channel *chn,
                                    unsigned int offset, unsigned int len)
 {
@@ -10321,6 +10376,15 @@ static int hlua_filter_parse_fct(char **args, int *cur_arg, struct proxy *px,
        if (lua_getfield(L, -1, "end_analyze") == LUA_TFUNCTION)
                hlua_flt_ops->channel_end_analyze = hlua_filter_end_analyze;
        lua_pop(L, 1);
+       if (lua_getfield(L, -1, "http_headers") == LUA_TFUNCTION)
+               hlua_flt_ops->http_headers = hlua_filter_http_headers;
+       lua_pop(L, 1);
+       if (lua_getfield(L, -1, "http_payload") == LUA_TFUNCTION)
+               hlua_flt_ops->http_payload = hlua_filter_http_payload;
+       lua_pop(L, 1);
+       if (lua_getfield(L, -1, "http_end") == LUA_TFUNCTION)
+               hlua_flt_ops->http_end = hlua_filter_http_end;
+       lua_pop(L, 1);
        if (lua_getfield(L, -1, "tcp_payload") == LUA_TFUNCTION)
                hlua_flt_ops->tcp_payload = hlua_filter_tcp_payload;
        lua_pop(L, 1);