feat: allow not pass trailers in nginx upstream

Author: bzp2010

lib/resty/apisix/upstream.lua

@@ -5,6 +5,7 @@ local get_phase = ngx.get_phase
 local C = ffi.C
 local NGX_ERROR = ngx.ERROR
 local NGX_OK = ngx.OK
+local type = type
 
 
 base.allows_subsystem("http")
@@ -15,6 +16,8 @@ typedef intptr_t        ngx_int_t;
 ngx_int_t ngx_http_apisix_upstream_set_cert_and_key(ngx_http_request_t *r, void *cert, void *key);
 ngx_int_t ngx_http_apisix_upstream_set_ssl_trusted_store(ngx_http_request_t *r, void *store);
 int ngx_http_apisix_upstream_set_ssl_verify(ngx_http_request_t *r, int verify);
+
+ngx_int_t ngx_http_apisix_set_upstream_pass_trailers(ngx_http_request_t *r, int on);
 ]])
 local _M = {}
 
@@ -106,4 +109,19 @@ end
 _M.set_ssl_verify = set_ssl_verify
 
 
+function _M.set_pass_trailers(on)
+    if type(on) ~= 'boolean' then
+        return nil, "on expects a boolean but found " .. type(on)
+    end
+
+    local r = get_request()
+    local ret = C.ngx_http_apisix_set_upstream_pass_trailers(r, on and 1 or 0)
+    if ret == NGX_ERROR then
+        return nil, "error while setting upstream pass_trailers"
+    end
+
+    return true
+end
+
+
 return _M

patch/1.25.3.1/nginx-upstream_pass_trailer.patch

@@ -0,0 +1,27 @@
+diff --git a/src/http/ngx_http_upstream.c b/src/http/ngx_http_upstream.c
+index d29e503cb..014082d30 100644
+--- a/src/http/ngx_http_upstream.c
++++ b/src/http/ngx_http_upstream.c
+@@ -8,6 +8,9 @@
+ #include <ngx_config.h>
+ #include <ngx_core.h>
+ #include <ngx_http.h>
++#if (NGX_HTTP_APISIX)
++#include <ngx_http_apisix_module.h>
++#endif
+ 
+ 
+ #if (NGX_HTTP_CACHE)
+@@ -2977,6 +2980,12 @@ ngx_http_upstream_process_trailers(ngx_http_request_t *r,
+         return NGX_OK;
+     }
+ 
++#if (NGX_HTTP_APISIX)
++    if (!ngx_http_apisix_is_upstream_pass_trailers(r)) {
++        return NGX_OK;
++    }
++#endif
++
+     part = &u->headers_in.trailers.part;
+     h = part->elts;
+ 

patch/1.27.1.1/nginx-upstream_pass_trailer.patch

@@ -0,0 +1,27 @@
+diff --git a/src/http/ngx_http_upstream.c b/src/http/ngx_http_upstream.c
+index d29e503cb..014082d30 100644
+--- a/src/http/ngx_http_upstream.c
++++ b/src/http/ngx_http_upstream.c
+@@ -8,6 +8,9 @@
+ #include <ngx_config.h>
+ #include <ngx_core.h>
+ #include <ngx_http.h>
++#if (NGX_HTTP_APISIX)
++#include <ngx_http_apisix_module.h>
++#endif
+ 
+ 
+ #if (NGX_HTTP_CACHE)
+@@ -2977,6 +2980,12 @@ ngx_http_upstream_process_trailers(ngx_http_request_t *r,
+         return NGX_OK;
+     }
+ 
++#if (NGX_HTTP_APISIX)
++    if (!ngx_http_apisix_is_upstream_pass_trailers(r)) {
++        return NGX_OK;
++    }
++#endif
++
+     part = &u->headers_in.trailers.part;
+     h = part->elts;
+ 

src/ngx_http_apisix_module.c

@@ -1048,3 +1048,34 @@ ngx_http_apisix_error_log_request_id(ngx_conf_t *cf, ngx_command_t *cmd, void *c
     return NGX_CONF_OK;
 }
 
+
+ngx_int_t
+ngx_http_apisix_set_upstream_pass_trailers(ngx_http_request_t *r, int on)
+{
+    ngx_http_apisix_ctx_t       *ctx;
+
+    ctx = ngx_http_apisix_get_module_ctx(r);
+
+    if (ctx == NULL) {
+        return NGX_ERROR;
+    }
+
+    ctx->upstream_pass_trailers = on;
+    ctx->upstream_pass_trailers_set = 1;
+    return NGX_OK;
+}
+
+
+ngx_int_t
+ngx_http_apisix_is_upstream_pass_trailers(ngx_http_request_t *r)
+{
+    ngx_http_apisix_ctx_t          *ctx;
+
+    ctx = ngx_http_apisix_get_module_ctx(r);
+
+    if (ctx != NULL && ctx->upstream_pass_trailers_set) {
+        return ctx->upstream_pass_trailers;
+    }
+
+    return 1;
+}

src/ngx_http_apisix_module.h

@@ -37,6 +37,8 @@ typedef struct {
     unsigned             body_filter_by_lua_skipped:1;
     unsigned             upstream_ssl_verify:1;
     unsigned             upstream_ssl_verify_set:1;
+    unsigned             upstream_pass_trailers:1;
+    unsigned             upstream_pass_trailers_set:1;
 } ngx_http_apisix_ctx_t;
 
 

t/upstream_pass_trailers.t

@@ -0,0 +1,94 @@
+use t::APISIX_NGINX 'no_plan';
+
+run_tests();
+
+add_block_preprocessor(sub {
+    my ($block) = @_;
+
+    if (!$block->request) {
+        $block->set_value("request", "");
+    }
+});
+
+__DATA__
+
+=== TEST 1: pass upstream trailers to downstream
+This is the default behavior in the nginx upstream unless we change it.
+--- config
+location /up {
+    # The trailer exists, but the Trailer header does not, which is an invalid response.
+    add_trailer "foo" "bar";
+    echo "hello";
+}
+location /t {
+    content_by_lua_block {
+        local sock = ngx.socket.tcp()
+
+        local ok, err = sock:connect("127.0.0.1", ngx.var.server_port)
+        if not ok then
+            ngx.say("failed to connect: ", err)
+            return
+        end
+        
+        local _, err = sock:send("GET /up HTTP/1.1\r\nHost: 127.0.0.1:1984\r\nUser-Agent: curl/8.5.0\r\nAccept: */*\r\nConnection: close\r\n\r\n")
+        if err then
+            ngx.say("failed to send: ", err)
+            return
+        end
+
+        local data, err, partial = sock:receive("*a")
+        if err then
+            ngx.say("failed to receive: ", err)
+            return
+        end
+
+        assert(string.find(data, "HTTP/1.1 200 OK", 1, true), "status not 200")
+        assert(not string.find(data, "Trailer: foo", 1, true), "exist trailer header")
+        assert(string.find(data, "foo: bar", 1, true), "missing trailer")
+    }
+}
+--- request
+GET /t
+
+
+
+=== TEST 2: do not pass upstream trailers to downstream
+--- config
+location /up {
+    add_trailer "foo" "bar";
+    echo "hello";
+}
+location /t {
+    access_by_lua_block {
+        local upstream = require("resty.apisix.upstream")
+        assert(upstream.set_pass_trailers(false))
+    }
+
+    content_by_lua_block {
+        local sock = ngx.socket.tcp()
+
+        local ok, err = sock:connect("127.0.0.1", ngx.var.server_port)
+        if not ok then
+            ngx.say("failed to connect: ", err)
+            return
+        end
+        
+        local _, err = sock:send("GET /up HTTP/1.1\r\nHost: 127.0.0.1:1984\r\nUser-Agent: curl/8.5.0\r\nAccept: */*\r\nConnection: close\r\n\r\n")
+        if err then
+            ngx.say("failed to send: ", err)
+            return
+        end
+
+        local data, err, partial = sock:receive("*a")
+        if err then
+            ngx.say("failed to receive: ", err)
+            return
+        end
+
+        assert(string.find(data, "HTTP/1.1 200 OK", 1, true), "status not 200")
+        assert(not string.find(data, "Trailer: foo", 1, true), "exist trailer header")
+        assert(not string.find(data, "foo: bar", 1, true), "exist trailer")
+    }
+}
+--- request
+GET /t