feature: allow use of ngx.exit() in the context of body_filter_by_lua

Author: rainingmaster

README.markdown

@@ -5223,7 +5223,7 @@ ngx.exit
 --------
 **syntax:** *ngx.exit(status)*
 
-**context:** *rewrite_by_lua*, access_by_lua*, content_by_lua*, header_filter_by_lua*, ngx.timer.*, balancer_by_lua*, ssl_certificate_by_lua*, ssl_session_fetch_by_lua*, ssl_session_store_by_lua**
+**context:** *rewrite_by_lua*, access_by_lua*, content_by_lua*, header_filter_by_lua*, body_filter_by_lua*, ngx.timer.*, balancer_by_lua*, ssl_certificate_by_lua*, ssl_session_fetch_by_lua*, ssl_session_store_by_lua**
 
 When `status >= 200` (i.e., `ngx.HTTP_OK` and above), it will interrupt the execution of the current request and return status code to nginx.
 

src/ngx_http_lua_bodyfilterby.c

@@ -87,11 +87,15 @@ ngx_http_lua_body_filter_by_chunk(lua_State *L, ngx_http_request_t *r,
     ngx_chain_t *in)
 {
     ngx_int_t        rc;
+    ngx_chain_t     *cl;
     u_char          *err_msg;
     size_t           len;
 #if (NGX_PCRE)
     ngx_pool_t      *old_pool;
 #endif
+    ngx_http_lua_ctx_t          *ctx;
+
+    ctx = ngx_http_get_module_ctx(r, ngx_http_lua_module);
 
     dd("initialize nginx context in Lua VM, code chunk at stack top  sp = 1");
     ngx_http_lua_body_filter_by_lua_env(L, r, in);
@@ -114,6 +118,8 @@ ngx_http_lua_body_filter_by_chunk(lua_State *L, ngx_http_request_t *r,
     ngx_http_lua_pcre_malloc_done(old_pool);
 #endif
 
+    dd("rc == %d", (int) rc);
+
     if (rc != 0) {
 
         /*  error occurred */
@@ -140,6 +146,19 @@ ngx_http_lua_body_filter_by_chunk(lua_State *L, ngx_http_request_t *r,
 
     lua_settop(L, 0);
 
+    if (ctx->body_exited) {
+        /* send last content */
+        for (cl = in; cl->next; cl = cl->next) {
+            /* do nothing */
+        }
+        /* make ngx_http_write_filter_module happy */
+        cl->buf->last_buf = 1;
+
+        ctx->eof = 1;
+
+        return NGX_OK;
+    }
+
     if (rc == NGX_ERROR || rc >= NGX_HTTP_SPECIAL_RESPONSE) {
         return NGX_ERROR;
     }
@@ -169,15 +188,9 @@ ngx_http_lua_body_filter_inline(ngx_http_request_t *r, ngx_chain_t *in)
         return NGX_ERROR;
     }
 
-    rc = ngx_http_lua_body_filter_by_chunk(L, r, in);
+    dd("calling body filter by chunk");
 
-    dd("body filter by chunk returns %d", (int) rc);
-
-    if (rc != NGX_OK) {
-        return NGX_ERROR;
-    }
-
-    return NGX_OK;
+    return ngx_http_lua_body_filter_by_chunk(L, r, in);
 }
 
 
@@ -218,13 +231,7 @@ ngx_http_lua_body_filter_file(ngx_http_request_t *r, ngx_chain_t *in)
     /*  make sure we have a valid code chunk */
     ngx_http_lua_assert(lua_isfunction(L, -1));
 
-    rc = ngx_http_lua_body_filter_by_chunk(L, r, in);
-
-    if (rc != NGX_OK) {
-        return NGX_ERROR;
-    }
-
-    return NGX_OK;
+    return ngx_http_lua_body_filter_by_chunk(L, r, in);
 }
 
 
@@ -264,6 +271,10 @@ ngx_http_lua_body_filter(ngx_http_request_t *r, ngx_chain_t *in)
         }
     }
 
+    if (ctx->body_exited) {
+        return NGX_OK;
+    }
+
     if (ctx->seen_last_in_filter) {
         for (/* void */; in; in = in->next) {
             dd("mark the buf as consumed: %d", (int) ngx_buf_size(in->buf));

src/ngx_http_lua_common.h

@@ -487,6 +487,8 @@ typedef struct ngx_http_lua_ctx_s {
 
     unsigned         exited:1;
 
+    unsigned         body_exited:1;
+
     unsigned         eof:1;             /*  1: last_buf has been sent;
                                             0: last_buf not sent yet */
 

src/ngx_http_lua_control.c

@@ -319,11 +319,18 @@ ngx_http_lua_ngx_exit(lua_State *L)
                                | NGX_HTTP_LUA_CONTEXT_CONTENT
                                | NGX_HTTP_LUA_CONTEXT_TIMER
                                | NGX_HTTP_LUA_CONTEXT_HEADER_FILTER
+                               | NGX_HTTP_LUA_CONTEXT_BODY_FILTER
                                | NGX_HTTP_LUA_CONTEXT_BALANCER
                                | NGX_HTTP_LUA_CONTEXT_SSL_CERT
                                | NGX_HTTP_LUA_CONTEXT_SSL_SESS_STORE
                                | NGX_HTTP_LUA_CONTEXT_SSL_SESS_FETCH);
 
+    /* rc is useless in bodyfilter phase */
+    if (ctx->context & NGX_HTTP_LUA_CONTEXT_BODY_FILTER) {
+        ctx->body_exited = 1;
+        return 0;
+    }
+
     rc = (ngx_int_t) luaL_checkinteger(L, 1);
 
     if (ctx->context & (NGX_HTTP_LUA_CONTEXT_SSL_CERT
@@ -470,6 +477,7 @@ ngx_http_lua_ffi_exit(ngx_http_request_t *r, int status, u_char *err,
                                        | NGX_HTTP_LUA_CONTEXT_CONTENT
                                        | NGX_HTTP_LUA_CONTEXT_TIMER
                                        | NGX_HTTP_LUA_CONTEXT_HEADER_FILTER
+                                       | NGX_HTTP_LUA_CONTEXT_BODY_FILTER
                                        | NGX_HTTP_LUA_CONTEXT_BALANCER
                                        | NGX_HTTP_LUA_CONTEXT_SSL_CERT
                                        | NGX_HTTP_LUA_CONTEXT_SSL_SESS_STORE
@@ -541,6 +549,7 @@ ngx_http_lua_ffi_exit(ngx_http_request_t *r, int status, u_char *err,
                    "lua exit with code %i", ctx->exit_code);
 
     if (ctx->context & (NGX_HTTP_LUA_CONTEXT_HEADER_FILTER
+                        | NGX_HTTP_LUA_CONTEXT_BODY_FILTER
                         | NGX_HTTP_LUA_CONTEXT_BALANCER))
     {
         return NGX_DONE;

t/082-body-filter.t

@@ -10,7 +10,7 @@ log_level('debug');
 
 repeat_each(2);
 
-plan tests => repeat_each() * (blocks() * 3 + 11);
+plan tests => repeat_each() * (blocks() * 3 + 8);
 
 #no_diff();
 no_long_string();
@@ -837,3 +837,73 @@ GET /lua
 --- ignore_response
 --- error_log
 API disabled in the context of body_filter_by_lua*
+
+
+
+=== TEST 27: exit 444
+--- config
+    location = /t {
+        content_by_lua_block {
+            ngx.say("111")
+            ngx.say("222")
+            ngx.say("333")
+        }
+
+        body_filter_by_lua_block {
+            ngx.exit(444)
+        }
+    }
+--- request
+    GET /t
+--- response_body
+111
+--- error_code: 200
+--- no_error_log
+
+
+
+=== TEST 28: exit OK
+--- config
+    location = /t {
+        content_by_lua_block {
+            ngx.say("111")
+            ngx.say("222")
+            ngx.say("333")
+        }
+
+        body_filter_by_lua_block {
+            ngx.exit(200)
+        }
+    }
+--- request
+    GET /t
+--- response_body
+111
+--- error_code: 200
+--- no_error_log
+
+
+
+=== TEST 29: in 2nd times
+--- config
+    location = /t {
+        content_by_lua_block {
+            ngx.say("111")
+            ngx.say("222")
+            ngx.say("333")
+        }
+
+        body_filter_by_lua_block {
+            ngx.ctx.times = (ngx.ctx.times or 0) + 1
+            if ngx.ctx.times == 2 then
+                ngx.exit(444)
+            end
+        }
+    }
+--- request
+    GET /t
+--- response_body
+111
+222
+--- error_code: 200
+--- no_error_log