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[nginx] Upstream: construct upstream peers from DNS SRV records.

Anonymous User
November 07, 2024 11:00AM
details: https://github.com/nginx/nginx/commit/9fe119b431c957824d7bed75fce47dfbda74ca33
branches: master
commit: 9fe119b431c957824d7bed75fce47dfbda74ca33
user: Dmitry Volyntsev <xeioex@nginx.com>
date: Thu, 17 Mar 2016 18:42:31 +0300
description:
Upstream: construct upstream peers from DNS SRV records.


---
src/http/modules/ngx_http_upstream_zone_module.c | 183 ++++++++++++++++++----
src/http/ngx_http_upstream.c | 38 +++++
src/http/ngx_http_upstream.h | 3 +-
src/http/ngx_http_upstream_round_robin.c | 12 +-
src/http/ngx_http_upstream_round_robin.h | 3 +-
src/stream/ngx_stream_upstream.c | 45 +++++-
src/stream/ngx_stream_upstream.h | 4 +-
src/stream/ngx_stream_upstream_round_robin.c | 12 +-
src/stream/ngx_stream_upstream_round_robin.h | 3 +-
src/stream/ngx_stream_upstream_zone_module.c | 184 +++++++++++++++++++----
10 files changed, 420 insertions(+), 67 deletions(-)

diff --git a/src/http/modules/ngx_http_upstream_zone_module.c b/src/http/modules/ngx_http_upstream_zone_module.c
index 355df39ab..e3ede9268 100644
--- a/src/http/modules/ngx_http_upstream_zone_module.c
+++ b/src/http/modules/ngx_http_upstream_zone_module.c
@@ -359,6 +359,18 @@ ngx_http_upstream_zone_copy_peer(ngx_http_upstream_rr_peers_t *peers,
dst->host->name.len = src->host->name.len;
ngx_memcpy(dst->host->name.data, src->host->name.data,
src->host->name.len);
+
+ if (src->host->service.len) {
+ dst->host->service.data = ngx_slab_alloc_locked(pool,
+ src->host->service.len);
+ if (dst->host->service.data == NULL) {
+ goto failed;
+ }
+
+ dst->host->service.len = src->host->service.len;
+ ngx_memcpy(dst->host->service.data, src->host->service.data,
+ src->host->service.len);
+ }
}
}

@@ -367,6 +379,10 @@ ngx_http_upstream_zone_copy_peer(ngx_http_upstream_rr_peers_t *peers,
failed:

if (dst->host) {
+ if (dst->host->name.data) {
+ ngx_slab_free_locked(pool, dst->host->name.data);
+ }
+
ngx_slab_free_locked(pool, dst->host);
}

@@ -510,6 +526,7 @@ ngx_http_upstream_zone_resolve_timer(ngx_event_t *event)
ctx->handler = ngx_http_upstream_zone_resolve_handler;
ctx->data = host;
ctx->timeout = uscf->resolver_timeout;
+ ctx->service = host->service;
ctx->cancelable = 1;

if (ngx_resolve_name(ctx) == NGX_OK) {
@@ -522,15 +539,28 @@ retry:
}


+#define ngx_http_upstream_zone_addr_marked(addr) \
+ ((uintptr_t) (addr)->sockaddr & 1)
+
+#define ngx_http_upstream_zone_mark_addr(addr) \
+ (addr)->sockaddr = (struct sockaddr *) ((uintptr_t) (addr)->sockaddr | 1)
+
+#define ngx_http_upstream_zone_unmark_addr(addr) \
+ (addr)->sockaddr = \
+ (struct sockaddr *) ((uintptr_t) (addr)->sockaddr & ~((uintptr_t) 1))
+
static void
ngx_http_upstream_zone_resolve_handler(ngx_resolver_ctx_t *ctx)
{
time_t now;
+ u_short min_priority;
in_port_t port;
+ ngx_str_t *server;
ngx_msec_t timer;
- ngx_uint_t i, j;
+ ngx_uint_t i, j, backup, addr_backup;
ngx_event_t *event;
ngx_resolver_addr_t *addr;
+ ngx_resolver_srv_name_t *srv;
ngx_http_upstream_host_t *host;
ngx_http_upstream_rr_peer_t *peer, *template, **peerp;
ngx_http_upstream_rr_peers_t *peers;
@@ -546,11 +576,32 @@ ngx_http_upstream_zone_resolve_handler(ngx_resolver_ctx_t *ctx)

now = ngx_time();

+ for (i = 0; i < ctx->nsrvs; i++) {
+ srv = &ctx->srvs[i];
+
+ if (srv->state) {
+ ngx_log_error(NGX_LOG_ERR, event->log, 0,
+ "%V could not be resolved (%i: %s) "
+ "while resolving service %V of %V",
+ &srv->name, srv->state,
+ ngx_resolver_strerror(srv->state), &ctx->service,
+ &ctx->name);
+ }
+ }
+
if (ctx->state) {
- ngx_log_error(NGX_LOG_ERR, event->log, 0,
- "%V could not be resolved (%i: %s)",
- &ctx->name, ctx->state,
- ngx_resolver_strerror(ctx->state));
+ if (ctx->service.len) {
+ ngx_log_error(NGX_LOG_ERR, event->log, 0,
+ "service %V of %V could not be resolved (%i: %s)",
+ &ctx->service, &ctx->name, ctx->state,
+ ngx_resolver_strerror(ctx->state));
+
+ } else {
+ ngx_log_error(NGX_LOG_ERR, event->log, 0,
+ "%V could not be resolved (%i: %s)",
+ &ctx->name, ctx->state,
+ ngx_resolver_strerror(ctx->state));
+ }

if (ctx->state != NGX_RESOLVE_NXDOMAIN) {
ngx_http_upstream_rr_peers_unlock(peers);
@@ -566,6 +617,13 @@ ngx_http_upstream_zone_resolve_handler(ngx_resolver_ctx_t *ctx)
ctx->naddrs = 0;
}

+ backup = 0;
+ min_priority = 65535;
+
+ for (i = 0; i < ctx->naddrs; i++) {
+ min_priority = ngx_min(ctx->addrs[i].priority, min_priority);
+ }
+
#if (NGX_DEBUG)
{
u_char text[NGX_SOCKADDR_STRLEN];
@@ -573,14 +631,20 @@ ngx_http_upstream_zone_resolve_handler(ngx_resolver_ctx_t *ctx)

for (i = 0; i < ctx->naddrs; i++) {
len = ngx_sock_ntop(ctx->addrs[i].sockaddr, ctx->addrs[i].socklen,
- text, NGX_SOCKADDR_STRLEN, 0);
+ text, NGX_SOCKADDR_STRLEN, 1);

- ngx_log_debug3(NGX_LOG_DEBUG_HTTP, event->log, 0,
- "name %V was resolved to %*s", &host->name, len, text);
+ ngx_log_debug7(NGX_LOG_DEBUG_HTTP, event->log, 0,
+ "name %V was resolved to %*s "
+ "s:\"%V\" n:\"%V\" w:%d %s",
+ &host->name, len, text, &host->service,
+ &ctx->addrs[i].name, ctx->addrs[i].weight,
+ ctx->addrs[i].priority != min_priority ? "backup" : "");
}
}
#endif

+again:
+
for (peerp = &peers->peer; *peerp; /* void */ ) {
peer = *peerp;

@@ -592,14 +656,39 @@ ngx_http_upstream_zone_resolve_handler(ngx_resolver_ctx_t *ctx)

addr = &ctx->addrs[j];

- if (addr->name.len == 0
- && ngx_cmp_sockaddr(peer->sockaddr, peer->socklen,
- addr->sockaddr, addr->socklen, 0)
- == NGX_OK)
+ addr_backup = (addr->priority != min_priority);
+ if (addr_backup != backup) {
+ continue;
+ }
+
+ if (ngx_http_upstream_zone_addr_marked(addr)) {
+ continue;
+ }
+
+ if (ngx_cmp_sockaddr(peer->sockaddr, peer->socklen,
+ addr->sockaddr, addr->socklen,
+ host->service.len != 0)
+ != NGX_OK)
{
- addr->name.len = 1;
- goto next;
+ continue;
+ }
+
+ if (host->service.len) {
+ if (addr->name.len != peer->server.len
+ || ngx_strncmp(addr->name.data, peer->server.data,
+ addr->name.len))
+ {
+ continue;
+ }
+
+ if (template->weight == 1 && addr->weight != peer->weight) {
+ continue;
+ }
}
+
+ ngx_http_upstream_zone_mark_addr(addr);
+
+ goto next;
}

*peerp = peer->next;
@@ -618,8 +707,13 @@ ngx_http_upstream_zone_resolve_handler(ngx_resolver_ctx_t *ctx)

addr = &ctx->addrs[i];

- if (addr->name.len == 1) {
- addr->name.len = 0;
+ addr_backup = (addr->priority != min_priority);
+ if (addr_backup != backup) {
+ continue;
+ }
+
+ if (ngx_http_upstream_zone_addr_marked(addr)) {
+ ngx_http_upstream_zone_unmark_addr(addr);
continue;
}

@@ -631,21 +725,14 @@ ngx_http_upstream_zone_resolve_handler(ngx_resolver_ctx_t *ctx)
ngx_log_error(NGX_LOG_ERR, event->log, 0,
"cannot add new server to upstream \"%V\", "
"memory exhausted", peers->name);
- break;
+ goto done;
}

ngx_memcpy(peer->sockaddr, addr->sockaddr, addr->socklen);

- port = ((struct sockaddr_in *) template->sockaddr)->sin_port;
-
- switch (peer->sockaddr->sa_family) {
-#if (NGX_HAVE_INET6)
- case AF_INET6:
- ((struct sockaddr_in6 *) peer->sockaddr)->sin6_port = port;
- break;
-#endif
- default: /* AF_INET */
- ((struct sockaddr_in *) peer->sockaddr)->sin_port = port;
+ if (host->service.len == 0) {
+ port = ngx_inet_get_port(template->sockaddr);
+ ngx_inet_set_port(peer->sockaddr, port);
}

peer->socklen = addr->socklen;
@@ -654,9 +741,30 @@ ngx_http_upstream_zone_resolve_handler(ngx_resolver_ctx_t *ctx)
peer->name.data, NGX_SOCKADDR_STRLEN, 1);

peer->host = template->host;
- peer->server = template->server;

- peer->weight = template->weight;
+ server = host->service.len ? &addr->name : &template->server;
+
+ peer->server.data = ngx_slab_alloc(peers->shpool, server->len);
+ if (peer->server.data == NULL) {
+ ngx_http_upstream_rr_peer_free(peers, peer);
+
+ ngx_log_error(NGX_LOG_ERR, event->log, 0,
+ "cannot add new server to upstream \"%V\", "
+ "memory exhausted", peers->name);
+ goto done;
+ }
+
+ peer->server.len = server->len;
+ ngx_memcpy(peer->server.data, server->data, server->len);
+
+ if (host->service.len == 0) {
+ peer->weight = template->weight;
+
+ } else {
+ peer->weight = (template->weight != 1 ? template->weight
+ : addr->weight);
+ }
+
peer->effective_weight = peer->weight;
peer->max_conns = template->max_conns;
peer->max_fails = template->max_fails;
@@ -675,8 +783,25 @@ ngx_http_upstream_zone_resolve_handler(ngx_resolver_ctx_t *ctx)
ngx_http_upstream_zone_set_single(uscf);
}

+ if (host->service.len && peers->next) {
+ ngx_http_upstream_rr_peers_unlock(peers);
+
+ peers = peers->next;
+ backup = 1;
+
+ ngx_http_upstream_rr_peers_wlock(peers);
+
+ goto again;
+ }
+
+done:
+
ngx_http_upstream_rr_peers_unlock(peers);

+ while (++i < ctx->naddrs) {
+ ngx_http_upstream_zone_unmark_addr(&ctx->addrs[i]);
+ }
+
timer = (ngx_msec_t) 1000 * (ctx->valid > now ? ctx->valid - now + 1 : 1);

ngx_resolve_name_done(ctx);
diff --git a/src/http/ngx_http_upstream.c b/src/http/ngx_http_upstream.c
index efe772439..d090d1618 100644
--- a/src/http/ngx_http_upstream.c
+++ b/src/http/ngx_http_upstream.c
@@ -6306,6 +6306,19 @@ ngx_http_upstream_server(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
resolve = 1;
continue;
}
+
+ if (ngx_strncmp(value[i].data, "service=", 8) == 0) {
+
+ us->service.len = value[i].len - 8;
+ us->service.data = &value[i].data[8];
+
+ if (us->service.len == 0) {
+ ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "service is empty");
+ return NGX_CONF_ERROR;
+ }
+
+ continue;
+ }
#endif

goto invalid;
@@ -6321,6 +6334,15 @@ ngx_http_upstream_server(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
/* resolve at run time */
u.no_resolve = 1;
}
+
+ if (us->service.len && !resolve) {
+ ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
+ "service upstream \"%V\" requires "
+ "\"resolve\" parameter",
+ &u.url);
+ return NGX_CONF_ERROR;
+ }
+
#endif

if (ngx_parse_url(cf->pool, &u) != NGX_OK) {
@@ -6336,6 +6358,22 @@ ngx_http_upstream_server(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)

#if (NGX_HTTP_UPSTREAM_ZONE)

+ if (us->service.len && !u.no_port) {
+ ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
+ "service upstream \"%V\" may not have port",
+ &us->name);
+
+ return NGX_CONF_ERROR;
+ }
+
+ if (us->service.len && u.naddrs) {
+ ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
+ "service upstream \"%V\" requires domain name",
+ &us->name);
+
+ return NGX_CONF_ERROR;
+ }
+
if (resolve && u.naddrs == 0) {
ngx_addr_t *addr;

diff --git a/src/http/ngx_http_upstream.h b/src/http/ngx_http_upstream.h
index 0922021bd..57ee06f8d 100644
--- a/src/http/ngx_http_upstream.h
+++ b/src/http/ngx_http_upstream.h
@@ -106,9 +106,10 @@ typedef struct {

#if (NGX_HTTP_UPSTREAM_ZONE)
ngx_str_t host;
+ ngx_str_t service;
#endif

- NGX_COMPAT_BEGIN(4)
+ NGX_COMPAT_BEGIN(2)
NGX_COMPAT_END
} ngx_http_upstream_server_t;

diff --git a/src/http/ngx_http_upstream_round_robin.c b/src/http/ngx_http_upstream_round_robin.c
index cc1b6d1a2..5dbd4e626 100644
--- a/src/http/ngx_http_upstream_round_robin.c
+++ b/src/http/ngx_http_upstream_round_robin.c
@@ -176,6 +176,7 @@ ngx_http_upstream_init_round_robin(ngx_conf_t *cf,
}

peer[n].host->name = server[i].host;
+ peer[n].host->service = server[i].service;

peer[n].sockaddr = server[i].addrs[0].sockaddr;
peer[n].socklen = server[i].addrs[0].socklen;
@@ -245,7 +246,15 @@ ngx_http_upstream_init_round_robin(ngx_conf_t *cf,
}
}

- if (n + r == 0) {
+ if (n == 0
+#if (NGX_HTTP_UPSTREAM_ZONE)
+ && !resolve
+#endif
+ ) {
+ return NGX_OK;
+ }
+
+ if (n + r == 0 && !(us->flags & NGX_HTTP_UPSTREAM_BACKUP)) {
return NGX_OK;
}

@@ -293,6 +302,7 @@ ngx_http_upstream_init_round_robin(ngx_conf_t *cf,
}

peer[n].host->name = server[i].host;
+ peer[n].host->service = server[i].service;

peer[n].sockaddr = server[i].addrs[0].sockaddr;
peer[n].socklen = server[i].addrs[0].socklen;
diff --git a/src/http/ngx_http_upstream_round_robin.h b/src/http/ngx_http_upstream_round_robin.h
index 06437f405..084b0b886 100644
--- a/src/http/ngx_http_upstream_round_robin.h
+++ b/src/http/ngx_http_upstream_round_robin.h
@@ -24,6 +24,7 @@ typedef struct {
ngx_event_t event; /* must be first */
ngx_uint_t worker;
ngx_str_t name;
+ ngx_str_t service;
ngx_http_upstream_rr_peers_t *peers;
ngx_http_upstream_rr_peer_t *peer;
} ngx_http_upstream_host_t;
@@ -150,7 +151,7 @@ ngx_http_upstream_rr_peer_free_locked(ngx_http_upstream_rr_peers_t *peers,
ngx_slab_free_locked(peers->shpool, peer->sockaddr);
ngx_slab_free_locked(peers->shpool, peer->name.data);

- if (peer->server.data && (peer->host == NULL || peer->host->peer == peer)) {
+ if (peer->server.data) {
ngx_slab_free_locked(peers->shpool, peer->server.data);
}

diff --git a/src/stream/ngx_stream_upstream.c b/src/stream/ngx_stream_upstream.c
index a251cca00..be4f13016 100644
--- a/src/stream/ngx_stream_upstream.c
+++ b/src/stream/ngx_stream_upstream.c
@@ -523,6 +523,19 @@ ngx_stream_upstream_server(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
resolve = 1;
continue;
}
+
+ if (ngx_strncmp(value[i].data, "service=", 8) == 0) {
+
+ us->service.len = value[i].len - 8;
+ us->service.data = &value[i].data[8];
+
+ if (us->service.len == 0) {
+ ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "service is empty");
+ return NGX_CONF_ERROR;
+ }
+
+ continue;
+ }
#endif

goto invalid;
@@ -537,6 +550,15 @@ ngx_stream_upstream_server(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
/* resolve at run time */
u.no_resolve = 1;
}
+
+ if (us->service.len && !resolve) {
+ ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
+ "service upstream \"%V\" requires "
+ "\"resolve\" parameter",
+ &u.url);
+ return NGX_CONF_ERROR;
+ }
+
#endif

if (ngx_parse_url(cf->pool, &u) != NGX_OK) {
@@ -548,7 +570,12 @@ ngx_stream_upstream_server(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
return NGX_CONF_ERROR;
}

- if (u.no_port) {
+ if (u.no_port
+#if (NGX_STREAM_UPSTREAM_ZONE)
+ && us->service.len == 0
+#endif
+ )
+ {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"no port in upstream \"%V\"", &u.url);
return NGX_CONF_ERROR;
@@ -558,6 +585,22 @@ ngx_stream_upstream_server(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)

#if (NGX_STREAM_UPSTREAM_ZONE)

+ if (us->service.len && !u.no_port) {
+ ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
+ "service upstream \"%V\" may not have port",
+ &us->name);
+
+ return NGX_CONF_ERROR;
+ }
+
+ if (us->service.len && u.naddrs) {
+ ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
+ "service upstream \"%V\" requires domain name",
+ &us->name);
+
+ return NGX_CONF_ERROR;
+ }
+
if (resolve && u.naddrs == 0) {
ngx_addr_t *addr;

diff --git a/src/stream/ngx_stream_upstream.h b/src/stream/ngx_stream_upstream.h
index 686e9269c..c581aa0be 100644
--- a/src/stream/ngx_stream_upstream.h
+++ b/src/stream/ngx_stream_upstream.h
@@ -65,10 +65,8 @@ typedef struct {

#if (NGX_STREAM_UPSTREAM_ZONE)
ngx_str_t host;
+ ngx_str_t service;
#endif
-
- NGX_COMPAT_BEGIN(2)
- NGX_COMPAT_END
} ngx_stream_upstream_server_t;


diff --git a/src/stream/ngx_stream_upstream_round_robin.c b/src/stream/ngx_stream_upstream_round_robin.c
index a18171a39..e1903b3d2 100644
--- a/src/stream/ngx_stream_upstream_round_robin.c
+++ b/src/stream/ngx_stream_upstream_round_robin.c
@@ -183,6 +183,7 @@ ngx_stream_upstream_init_round_robin(ngx_conf_t *cf,
}

peer[n].host->name = server[i].host;
+ peer[n].host->service = server[i].service;

peer[n].sockaddr = server[i].addrs[0].sockaddr;
peer[n].socklen = server[i].addrs[0].socklen;
@@ -251,7 +252,15 @@ ngx_stream_upstream_init_round_robin(ngx_conf_t *cf,
}
}

- if (n + r == 0) {
+ if (n == 0
+#if (NGX_STREAM_UPSTREAM_ZONE)
+ && !resolve
+#endif
+ ) {
+ return NGX_OK;
+ }
+
+ if (n + r == 0 && !(us->flags & NGX_STREAM_UPSTREAM_BACKUP)) {
return NGX_OK;
}

@@ -299,6 +308,7 @@ ngx_stream_upstream_init_round_robin(ngx_conf_t *cf,
}

peer[n].host->name = server[i].host;
+ peer[n].host->service = server[i].service;

peer[n].sockaddr = server[i].addrs[0].sockaddr;
peer[n].socklen = server[i].addrs[0].socklen;
diff --git a/src/stream/ngx_stream_upstream_round_robin.h b/src/stream/ngx_stream_upstream_round_robin.h
index 5002200c2..707a9889d 100644
--- a/src/stream/ngx_stream_upstream_round_robin.h
+++ b/src/stream/ngx_stream_upstream_round_robin.h
@@ -24,6 +24,7 @@ typedef struct {
ngx_event_t event; /* must be first */
ngx_uint_t worker;
ngx_str_t name;
+ ngx_str_t service;
ngx_stream_upstream_rr_peers_t *peers;
ngx_stream_upstream_rr_peer_t *peer;
} ngx_stream_upstream_host_t;
@@ -148,7 +149,7 @@ ngx_stream_upstream_rr_peer_free_locked(ngx_stream_upstream_rr_peers_t *peers,
ngx_slab_free_locked(peers->shpool, peer->sockaddr);
ngx_slab_free_locked(peers->shpool, peer->name.data);

- if (peer->server.data && (peer->host == NULL || peer->host->peer == peer)) {
+ if (peer->server.data) {
ngx_slab_free_locked(peers->shpool, peer->server.data);
}

diff --git a/src/stream/ngx_stream_upstream_zone_module.c b/src/stream/ngx_stream_upstream_zone_module.c
index d731baf31..0d6ab89f3 100644
--- a/src/stream/ngx_stream_upstream_zone_module.c
+++ b/src/stream/ngx_stream_upstream_zone_module.c
@@ -356,6 +356,18 @@ ngx_stream_upstream_zone_copy_peer(ngx_stream_upstream_rr_peers_t *peers,
dst->host->name.len = src->host->name.len;
ngx_memcpy(dst->host->name.data, src->host->name.data,
src->host->name.len);
+
+ if (src->host->service.len) {
+ dst->host->service.data = ngx_slab_alloc_locked(pool,
+ src->host->service.len);
+ if (dst->host->service.data == NULL) {
+ goto failed;
+ }
+
+ dst->host->service.len = src->host->service.len;
+ ngx_memcpy(dst->host->service.data, src->host->service.data,
+ src->host->service.len);
+ }
}
}

@@ -364,6 +376,10 @@ ngx_stream_upstream_zone_copy_peer(ngx_stream_upstream_rr_peers_t *peers,
failed:

if (dst->host) {
+ if (dst->host->name.data) {
+ ngx_slab_free_locked(pool, dst->host->name.data);
+ }
+
ngx_slab_free_locked(pool, dst->host);
}

@@ -508,6 +524,7 @@ ngx_stream_upstream_zone_resolve_timer(ngx_event_t *event)
ctx->handler = ngx_stream_upstream_zone_resolve_handler;
ctx->data = host;
ctx->timeout = uscf->resolver_timeout;
+ ctx->service = host->service;
ctx->cancelable = 1;

if (ngx_resolve_name(ctx) == NGX_OK) {
@@ -520,15 +537,28 @@ retry:
}


+#define ngx_stream_upstream_zone_addr_marked(addr) \
+ ((uintptr_t) (addr)->sockaddr & 1)
+
+#define ngx_stream_upstream_zone_mark_addr(addr) \
+ (addr)->sockaddr = (struct sockaddr *) ((uintptr_t) (addr)->sockaddr | 1)
+
+#define ngx_stream_upstream_zone_unmark_addr(addr) \
+ (addr)->sockaddr = \
+ (struct sockaddr *) ((uintptr_t) (addr)->sockaddr & ~((uintptr_t) 1))
+
static void
ngx_stream_upstream_zone_resolve_handler(ngx_resolver_ctx_t *ctx)
{
time_t now;
+ u_short min_priority;
in_port_t port;
+ ngx_str_t *server;
ngx_msec_t timer;
- ngx_uint_t i, j;
+ ngx_uint_t i, j, backup, addr_backup;
ngx_event_t *event;
ngx_resolver_addr_t *addr;
+ ngx_resolver_srv_name_t *srv;
ngx_stream_upstream_host_t *host;
ngx_stream_upstream_rr_peer_t *peer, *template, **peerp;
ngx_stream_upstream_rr_peers_t *peers;
@@ -544,11 +574,32 @@ ngx_stream_upstream_zone_resolve_handler(ngx_resolver_ctx_t *ctx)

now = ngx_time();

+ for (i = 0; i < ctx->nsrvs; i++) {
+ srv = &ctx->srvs[i];
+
+ if (srv->state) {
+ ngx_log_error(NGX_LOG_ERR, event->log, 0,
+ "%V could not be resolved (%i: %s) "
+ "while resolving service %V of %V",
+ &srv->name, srv->state,
+ ngx_resolver_strerror(srv->state), &ctx->service,
+ &ctx->name);
+ }
+ }
+
if (ctx->state) {
- ngx_log_error(NGX_LOG_ERR, event->log, 0,
- "%V could not be resolved (%i: %s)",
- &ctx->name, ctx->state,
- ngx_resolver_strerror(ctx->state));
+ if (ctx->service.len) {
+ ngx_log_error(NGX_LOG_ERR, event->log, 0,
+ "service %V of %V could not be resolved (%i: %s)",
+ &ctx->service, &ctx->name, ctx->state,
+ ngx_resolver_strerror(ctx->state));
+
+ } else {
+ ngx_log_error(NGX_LOG_ERR, event->log, 0,
+ "%V could not be resolved (%i: %s)",
+ &ctx->name, ctx->state,
+ ngx_resolver_strerror(ctx->state));
+ }

if (ctx->state != NGX_RESOLVE_NXDOMAIN) {
ngx_stream_upstream_rr_peers_unlock(peers);
@@ -564,6 +615,13 @@ ngx_stream_upstream_zone_resolve_handler(ngx_resolver_ctx_t *ctx)
ctx->naddrs = 0;
}

+ backup = 0;
+ min_priority = 65535;
+
+ for (i = 0; i < ctx->naddrs; i++) {
+ min_priority = ngx_min(ctx->addrs[i].priority, min_priority);
+ }
+
#if (NGX_DEBUG)
{
u_char text[NGX_SOCKADDR_STRLEN];
@@ -571,14 +629,20 @@ ngx_stream_upstream_zone_resolve_handler(ngx_resolver_ctx_t *ctx)

for (i = 0; i < ctx->naddrs; i++) {
len = ngx_sock_ntop(ctx->addrs[i].sockaddr, ctx->addrs[i].socklen,
- text, NGX_SOCKADDR_STRLEN, 0);
+ text, NGX_SOCKADDR_STRLEN, 1);

- ngx_log_debug3(NGX_LOG_DEBUG_STREAM, event->log, 0,
- "name %V was resolved to %*s", &host->name, len, text);
+ ngx_log_debug7(NGX_LOG_DEBUG_STREAM, event->log, 0,
+ "name %V was resolved to %*s "
+ "s:\"%V\" n:\"%V\" w:%d %s",
+ &host->name, len, text, &host->service,
+ &ctx->addrs[i].name, ctx->addrs[i].weight,
+ ctx->addrs[i].priority != min_priority ? "backup" : "");
}
}
#endif

+again:
+
for (peerp = &peers->peer; *peerp; /* void */ ) {
peer = *peerp;

@@ -590,14 +654,39 @@ ngx_stream_upstream_zone_resolve_handler(ngx_resolver_ctx_t *ctx)

addr = &ctx->addrs[j];

- if (addr->name.len == 0
- && ngx_cmp_sockaddr(peer->sockaddr, peer->socklen,
- addr->sockaddr, addr->socklen, 0)
- == NGX_OK)
+ addr_backup = (addr->priority != min_priority);
+ if (addr_backup != backup) {
+ continue;
+ }
+
+ if (ngx_stream_upstream_zone_addr_marked(addr)) {
+ continue;
+ }
+
+ if (ngx_cmp_sockaddr(peer->sockaddr, peer->socklen,
+ addr->sockaddr, addr->socklen,
+ host->service.len != 0)
+ != NGX_OK)
{
- addr->name.len = 1;
- goto next;
+ continue;
}
+
+ if (host->service.len) {
+ if (addr->name.len != peer->server.len
+ || ngx_strncmp(addr->name.data, peer->server.data,
+ addr->name.len))
+ {
+ continue;
+ }
+
+ if (template->weight == 1 && addr->weight != peer->weight) {
+ continue;
+ }
+ }
+
+ ngx_stream_upstream_zone_mark_addr(addr);
+
+ goto next;
}

*peerp = peer->next;
@@ -616,33 +705,32 @@ ngx_stream_upstream_zone_resolve_handler(ngx_resolver_ctx_t *ctx)

addr = &ctx->addrs[i];

- if (addr->name.len == 1) {
- addr->name.len = 0;
+ addr_backup = (addr->priority != min_priority);
+ if (addr_backup != backup) {
+ continue;
+ }
+
+ if (ngx_stream_upstream_zone_addr_marked(addr)) {
+ ngx_stream_upstream_zone_unmark_addr(addr);
continue;
}

ngx_shmtx_lock(&peers->shpool->mutex);
peer = ngx_stream_upstream_zone_copy_peer(peers, NULL);
ngx_shmtx_unlock(&peers->shpool->mutex);
+
if (peer == NULL) {
ngx_log_error(NGX_LOG_ERR, event->log, 0,
"cannot add new server to upstream \"%V\", "
"memory exhausted", peers->name);
- break;
+ goto done;
}

ngx_memcpy(peer->sockaddr, addr->sockaddr, addr->socklen);

- port = ((struct sockaddr_in *) template->sockaddr)->sin_port;
-
- switch (peer->sockaddr->sa_family) {
-#if (NGX_HAVE_INET6)
- case AF_INET6:
- ((struct sockaddr_in6 *) peer->sockaddr)->sin6_port = port;
- break;
-#endif
- default: /* AF_INET */
- ((struct sockaddr_in *) peer->sockaddr)->sin_port = port;
+ if (host->service.len == 0) {
+ port = ngx_inet_get_port(template->sockaddr);
+ ngx_inet_set_port(peer->sockaddr, port);
}

peer->socklen = addr->socklen;
@@ -651,9 +739,30 @@ ngx_stream_upstream_zone_resolve_handler(ngx_resolver_ctx_t *ctx)
peer->name.data, NGX_SOCKADDR_STRLEN, 1);

peer->host = template->host;
- peer->server = template->server;

- peer->weight = template->weight;
+ server = host->service.len ? &addr->name : &template->server;
+
+ peer->server.data = ngx_slab_alloc(peers->shpool, server->len);
+ if (peer->server.data == NULL) {
+ ngx_stream_upstream_rr_peer_free(peers, peer);
+
+ ngx_log_error(NGX_LOG_ERR, event->log, 0,
+ "cannot add new server to upstream \"%V\", "
+ "memory exhausted", peers->name);
+ goto done;
+ }
+
+ peer->server.len = server->len;
+ ngx_memcpy(peer->server.data, server->data, server->len);
+
+ if (host->service.len == 0) {
+ peer->weight = template->weight;
+
+ } else {
+ peer->weight = (template->weight != 1 ? template->weight
+ : addr->weight);
+ }
+
peer->effective_weight = peer->weight;
peer->max_conns = template->max_conns;
peer->max_fails = template->max_fails;
@@ -672,8 +781,25 @@ ngx_stream_upstream_zone_resolve_handler(ngx_resolver_ctx_t *ctx)
ngx_stream_upstream_zone_set_single(uscf);
}

+ if (host->service.len && peers->next) {
+ ngx_stream_upstream_rr_peers_unlock(peers);
+
+ peers = peers->next;
+ backup = 1;
+
+ ngx_stream_upstream_rr_peers_wlock(peers);
+
+ goto again;
+ }
+
+done:
+
ngx_stream_upstream_rr_peers_unlock(peers);

+ while (++i < ctx->naddrs) {
+ ngx_stream_upstream_zone_unmark_addr(&ctx->addrs[i]);
+ }
+
timer = (ngx_msec_t) 1000 * (ctx->valid > now ? ctx->valid - now + 1 : 1);

ngx_resolve_name_done(ctx);
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[nginx] Upstream: construct upstream peers from DNS SRV records.

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