[nginx] Upstream: proxy_next_upstream non_idempotent.

[Maxim Dounin]

details:   http://hg.nginx.org/nginx/rev/91c8d990fb45
branches:  
changeset: 6467:91c8d990fb45
user:      Maxim Dounin <mdounin at mdounin.ru>
date:      Mon Mar 28 19:50:19 2016 +0300
description:
Upstream: proxy_next_upstream non_idempotent.

By default, requests with non-idempotent methods (POST, LOCK, PATCH)
are no longer retried in case of errors if a request was already sent
to a backend.  Previous behaviour can be restored by using
"proxy_next_upstream ... non_idempotent".

diffstat:

 src/http/modules/ngx_http_fastcgi_module.c |  1 +
 src/http/modules/ngx_http_proxy_module.c   |  1 +
 src/http/modules/ngx_http_scgi_module.c    |  1 +
 src/http/modules/ngx_http_uwsgi_module.c   |  1 +
 src/http/ngx_http_upstream.c               |  8 +++++++-
 src/http/ngx_http_upstream.h               |  1 +
 6 files changed, 12 insertions(+), 1 deletions(-)

diffs (74 lines):

diff --git a/src/http/modules/ngx_http_fastcgi_module.c b/src/http/modules/ngx_http_fastcgi_module.c
--- a/src/http/modules/ngx_http_fastcgi_module.c
+++ b/src/http/modules/ngx_http_fastcgi_module.c
@@ -206,6 +206,7 @@ static ngx_conf_bitmask_t  ngx_http_fast
     { ngx_string("error"), NGX_HTTP_UPSTREAM_FT_ERROR },
     { ngx_string("timeout"), NGX_HTTP_UPSTREAM_FT_TIMEOUT },
     { ngx_string("invalid_header"), NGX_HTTP_UPSTREAM_FT_INVALID_HEADER },
+    { ngx_string("non_idempotent"), NGX_HTTP_UPSTREAM_FT_NON_IDEMPOTENT },
     { ngx_string("http_500"), NGX_HTTP_UPSTREAM_FT_HTTP_500 },
     { ngx_string("http_503"), NGX_HTTP_UPSTREAM_FT_HTTP_503 },
     { ngx_string("http_403"), NGX_HTTP_UPSTREAM_FT_HTTP_403 },
diff --git a/src/http/modules/ngx_http_proxy_module.c b/src/http/modules/ngx_http_proxy_module.c
--- a/src/http/modules/ngx_http_proxy_module.c
+++ b/src/http/modules/ngx_http_proxy_module.c
@@ -213,6 +213,7 @@ static ngx_conf_bitmask_t  ngx_http_prox
     { ngx_string("error"), NGX_HTTP_UPSTREAM_FT_ERROR },
     { ngx_string("timeout"), NGX_HTTP_UPSTREAM_FT_TIMEOUT },
     { ngx_string("invalid_header"), NGX_HTTP_UPSTREAM_FT_INVALID_HEADER },
+    { ngx_string("non_idempotent"), NGX_HTTP_UPSTREAM_FT_NON_IDEMPOTENT },
     { ngx_string("http_500"), NGX_HTTP_UPSTREAM_FT_HTTP_500 },
     { ngx_string("http_502"), NGX_HTTP_UPSTREAM_FT_HTTP_502 },
     { ngx_string("http_503"), NGX_HTTP_UPSTREAM_FT_HTTP_503 },
diff --git a/src/http/modules/ngx_http_scgi_module.c b/src/http/modules/ngx_http_scgi_module.c
--- a/src/http/modules/ngx_http_scgi_module.c
+++ b/src/http/modules/ngx_http_scgi_module.c
@@ -77,6 +77,7 @@ static ngx_conf_bitmask_t ngx_http_scgi_
     { ngx_string("error"), NGX_HTTP_UPSTREAM_FT_ERROR },
     { ngx_string("timeout"), NGX_HTTP_UPSTREAM_FT_TIMEOUT },
     { ngx_string("invalid_header"), NGX_HTTP_UPSTREAM_FT_INVALID_HEADER },
+    { ngx_string("non_idempotent"), NGX_HTTP_UPSTREAM_FT_NON_IDEMPOTENT },
     { ngx_string("http_500"), NGX_HTTP_UPSTREAM_FT_HTTP_500 },
     { ngx_string("http_503"), NGX_HTTP_UPSTREAM_FT_HTTP_503 },
     { ngx_string("http_403"), NGX_HTTP_UPSTREAM_FT_HTTP_403 },
diff --git a/src/http/modules/ngx_http_uwsgi_module.c b/src/http/modules/ngx_http_uwsgi_module.c
--- a/src/http/modules/ngx_http_uwsgi_module.c
+++ b/src/http/modules/ngx_http_uwsgi_module.c
@@ -109,6 +109,7 @@ static ngx_conf_bitmask_t ngx_http_uwsgi
     { ngx_string("error"), NGX_HTTP_UPSTREAM_FT_ERROR },
     { ngx_string("timeout"), NGX_HTTP_UPSTREAM_FT_TIMEOUT },
     { ngx_string("invalid_header"), NGX_HTTP_UPSTREAM_FT_INVALID_HEADER },
+    { ngx_string("non_idempotent"), NGX_HTTP_UPSTREAM_FT_NON_IDEMPOTENT },
     { ngx_string("http_500"), NGX_HTTP_UPSTREAM_FT_HTTP_500 },
     { ngx_string("http_503"), NGX_HTTP_UPSTREAM_FT_HTTP_503 },
     { ngx_string("http_403"), NGX_HTTP_UPSTREAM_FT_HTTP_403 },
diff --git a/src/http/ngx_http_upstream.c b/src/http/ngx_http_upstream.c
--- a/src/http/ngx_http_upstream.c
+++ b/src/http/ngx_http_upstream.c
@@ -3989,8 +3989,14 @@ ngx_http_upstream_next(ngx_http_request_
 
     timeout = u->conf->next_upstream_timeout;
 
+    if (u->request_sent
+        && (r->method & (NGX_HTTP_POST|NGX_HTTP_LOCK|NGX_HTTP_PATCH)))
+    {
+        ft_type |= NGX_HTTP_UPSTREAM_FT_NON_IDEMPOTENT;
+    }
+
     if (u->peer.tries == 0
-        || !(u->conf->next_upstream & ft_type)
+        || ((u->conf->next_upstream & ft_type) != ft_type)
         || (u->request_sent && r->request_body_no_buffering)
         || (timeout && ngx_current_msec - u->peer.start_time >= timeout))
     {
diff --git a/src/http/ngx_http_upstream.h b/src/http/ngx_http_upstream.h
--- a/src/http/ngx_http_upstream.h
+++ b/src/http/ngx_http_upstream.h
@@ -29,6 +29,7 @@
 #define NGX_HTTP_UPSTREAM_FT_UPDATING        0x00000400
 #define NGX_HTTP_UPSTREAM_FT_BUSY_LOCK       0x00000800
 #define NGX_HTTP_UPSTREAM_FT_MAX_WAITING     0x00001000
+#define NGX_HTTP_UPSTREAM_FT_NON_IDEMPOTENT  0x00002000
 #define NGX_HTTP_UPSTREAM_FT_NOLIVE          0x40000000
 #define NGX_HTTP_UPSTREAM_FT_OFF             0x80000000