MINOR: stats: store the parent proxy in stats ctx (http)

Some HTTP related stats functions need to know the parent proxy, mainly
to get a pointer on the related uri_auth set by the proxy or to check
scope settings.

The current design (probably historical as only the http context existed
by then) took the other approach: it propagates the uri pointer from the
http context deep down the calling stack up to the relevant functions.
For non-http contexts (cli), the pointer is set to NULL.

Doing so is not very pretty and not easy to maintain. Moreover, there were
still some places in the code were the uri pointer was learned directly
from the stream proxy because the argument was not available as argument
from those functions. This is error-prone, because if one day we decide to
change the source proxy in the parent function, we might still have some
functions down the stack that ignore the top most argument and still do
on their own, and we'll probably end up with inconsistencies.

So in this patch, we take a safer approach: the caller responsible for
creating the stats applet should set the http_px pointer so that any stats
function running under the applet that needs to know if it's running in
http context or needs to access parent proxy info may do so thanks to
the dedicated ctx->http_px pointer.

diff --git a/include/haproxy/stats-t.h b/include/haproxy/stats-t.h
index b6feabd158cca9d5fd85bab0f1c10b1a6a9abcdc..34a4cc256aca0d42ca96257397bf7c7ffa832673 100644 (file)
--- a/include/haproxy/stats-t.h
+++ b/include/haproxy/stats-t.h
@@ -550,6 +550,7 @@ enum stats_domain_px_cap {
 
 /* the context of a "show stat" command in progress on the CLI or the stats applet */
 struct show_stat_ctx {
+       struct proxy *http_px;  /* parent proxy of the current applet (only relevant for HTTP applet) */
        void *obj1;             /* context pointer used in stats dump */
        void *obj2;             /* context pointer used in stats dump */
        uint32_t domain;        /* set the stats to used, for now only proxy stats are supported */

diff --git a/src/http_ana.c b/src/http_ana.c
index fc0922ccc28f37db65c87a9635e3caf0fed474c6..9532be4a36778f243f31549bdeb52f3f11fe789f 100644 (file)
--- a/src/http_ana.c
+++ b/src/http_ana.c
@@ -3875,6 +3875,7 @@ static int http_handle_stats(struct stream *s, struct channel *req)
        appctx->st1 = 0;
        ctx->state = STAT_STATE_INIT;
        ctx->st_code = STAT_STATUS_INIT;
+       ctx->http_px = s->be;
        ctx->flags |= uri_auth->flags;
        ctx->flags |= STAT_FMT_HTML; /* assume HTML mode by default */
        if ((msg->flags & HTTP_MSGF_VER_11) && (txn->meth != HTTP_METH_HEAD))

diff --git a/src/stats.c b/src/stats.c
index bcc70cb36ebed66312435499a46baf8cea59a4eb..b4c35b37044227c43ef492873399d9404d630352 100644 (file)
--- a/src/stats.c
+++ b/src/stats.c
@@ -2991,8 +2991,8 @@ static int stats_dump_be_stats(struct stconn *sc, struct proxy *px)
 }
 
 /* Dumps the HTML table header for proxy <px> to the local trash buffer for and
- * uses the state from stream connector <sc> and per-uri parameters <uri>. The
- * caller is responsible for clearing the local trash buffer if needed.
+ * uses the state from stream connector <sc>. The caller is responsible for
+ * clearing the local trash buffer if needed.
  */
 static void stats_dump_html_px_hdr(struct stconn *sc, struct proxy *px)
 {
@@ -3146,20 +3146,22 @@ static void stats_dump_html_px_end(struct stconn *sc, struct proxy *px)
  * input buffer. Returns 0 if it had to stop dumping data because of lack of
  * buffer space, or non-zero if everything completed. This function is used
  * both by the CLI and the HTTP entry points, and is able to dump the output
- * in HTML or CSV formats. If the later, <uri> must be NULL.
+ * in HTML or CSV formats.
  */
 int stats_dump_proxy_to_buffer(struct stconn *sc, struct htx *htx,
-                              struct proxy *px, struct uri_auth *uri)
+                              struct proxy *px)
 {
        struct appctx *appctx = __sc_appctx(sc);
        struct show_stat_ctx *ctx = appctx->svcctx;
-       struct stream *s = __sc_strm(sc);
        struct channel *rep = sc_ic(sc);
        struct server *sv, *svs;        /* server and server-state, server-state=server or server->track */
        struct listener *l;
+       struct uri_auth *uri = NULL;
        int current_field;
        int px_st = ctx->px_st;
 
+       if (ctx->http_px)
+               uri = ctx->http_px->uri_auth;
        chunk_reset(&trash_chunk);
 more:
        current_field = ctx->field;
@@ -3181,7 +3183,7 @@ more:
                                        break;
 
                                /* match '.' which means 'self' proxy */
-                               if (strcmp(scope->px_id, ".") == 0 && px == s->be)
+                               if (strcmp(scope->px_id, ".") == 0 && px == ctx->http_px)
                                        break;
                                scope = scope->next;
                        }
@@ -3401,13 +3403,17 @@ more:
        return 0;
 }
 
-/* Dumps the HTTP stats head block to the local trash buffer for and uses the
- * per-uri parameters <uri>. The caller is responsible for clearing the local
- * trash buffer if needed.
+/* Dumps the HTTP stats head block to the local trash buffer and uses the
+ * per-uri parameters from the parent proxy. The caller is responsible for
+ * clearing the local trash buffer if needed.
  */
-static void stats_dump_html_head(struct appctx *appctx, struct uri_auth *uri)
+static void stats_dump_html_head(struct appctx *appctx)
 {
        struct show_stat_ctx *ctx = appctx->svcctx;
+       struct uri_auth *uri;
+
+       BUG_ON(!ctx->http_px);
+       uri = ctx->http_px->uri_auth;
 
        /* WARNING! This must fit in the first buffer !!! */
        chunk_appendf(&trash_chunk,
@@ -3570,20 +3576,24 @@ static void stats_dump_html_head(struct appctx *appctx, struct uri_auth *uri)
                      );
 }
 
-/* Dumps the HTML stats information block to the local trash buffer for and uses
- * the state from stream connector <sc> and per-uri parameters <uri>. The caller
- * is responsible for clearing the local trash buffer if needed.
+/* Dumps the HTML stats information block to the local trash buffer and uses
+ * the state from stream connector <sc> and per-uri parameter from the parent
+ * proxy. The caller is responsible for clearing the local trash buffer if
+ * needed.
  */
-static void stats_dump_html_info(struct stconn *sc, struct uri_auth *uri)
+static void stats_dump_html_info(struct stconn *sc)
 {
        struct appctx *appctx = __sc_appctx(sc);
        struct show_stat_ctx *ctx = appctx->svcctx;
        unsigned int up = ns_to_sec(now_ns - start_time_ns);
        char scope_txt[STAT_SCOPE_TXT_MAXLEN + sizeof STAT_SCOPE_PATTERN];
        const char *scope_ptr = stats_scope_ptr(appctx, sc);
+       struct uri_auth *uri;
        unsigned long long bps;
        int thr;
 
+       BUG_ON(!ctx->http_px);
+       uri = ctx->http_px->uri_auth;
        for (bps = thr = 0; thr < global.nbthread; thr++)
                bps += 32ULL * read_freq_ctr(&ha_thread_ctx[thr].out_32bps);
 
@@ -3860,8 +3870,7 @@ static void stats_dump_json_end()
  * a pointer to the current server/listener.
  */
 static int stats_dump_proxies(struct stconn *sc,
-                              struct htx *htx,
-                              struct uri_auth *uri)
+                              struct htx *htx)
 {
        struct appctx *appctx = __sc_appctx(sc);
        struct show_stat_ctx *ctx = appctx->svcctx;
@@ -3890,7 +3899,7 @@ static int stats_dump_proxies(struct stconn *sc,
                 */
                if (!(px->flags & PR_FL_DISABLED) && px->uuid > 0 &&
                    (px->cap & (PR_CAP_FE | PR_CAP_BE)) && !(px->cap & PR_CAP_INT)) {
-                       if (stats_dump_proxy_to_buffer(sc, htx, px, uri) == 0)
+                       if (stats_dump_proxy_to_buffer(sc, htx, px) == 0)
                                return 0;
                }
 
@@ -3906,14 +3915,12 @@ static int stats_dump_proxies(struct stconn *sc,
 }
 
 /* This function dumps statistics onto the stream connector's read buffer in
- * either CSV or HTML format. <uri> contains some HTML-specific parameters that
- * are ignored for CSV format (hence <uri> may be NULL there). It returns 0 if
- * it had to stop writing data and an I/O is needed, 1 if the dump is finished
- * and the stream must be closed, or -1 in case of any error. This function is
- * used by both the CLI and the HTTP handlers.
+ * either CSV or HTML format. It returns 0 if it had to stop writing data and
+ * an I/O is needed, 1 if the dump is finished and the stream must be closed,
+ * or -1 in case of any error. This function is used by both the CLI and the
+ * HTTP handlers.
  */
-static int stats_dump_stat_to_buffer(struct stconn *sc, struct htx *htx,
-                                    struct uri_auth *uri)
+static int stats_dump_stat_to_buffer(struct stconn *sc, struct htx *htx)
 {
        struct appctx *appctx = __sc_appctx(sc);
        struct show_stat_ctx *ctx = appctx->svcctx;
@@ -3928,7 +3935,7 @@ static int stats_dump_stat_to_buffer(struct stconn *sc, struct htx *htx,
 
        case STAT_STATE_HEAD:
                if (ctx->flags & STAT_FMT_HTML)
-                       stats_dump_html_head(appctx, uri);
+                       stats_dump_html_head(appctx);
                else if (ctx->flags & STAT_JSON_SCHM)
                        stats_dump_json_schema(&trash_chunk);
                else if (ctx->flags & STAT_FMT_JSON)
@@ -3948,7 +3955,7 @@ static int stats_dump_stat_to_buffer(struct stconn *sc, struct htx *htx,
 
        case STAT_STATE_INFO:
                if (ctx->flags & STAT_FMT_HTML) {
-                       stats_dump_html_info(sc, uri);
+                       stats_dump_html_info(sc);
                        if (!stats_putchk(appctx, htx))
                                goto full;
                }
@@ -3974,7 +3981,7 @@ static int stats_dump_stat_to_buffer(struct stconn *sc, struct htx *htx,
                case STATS_DOMAIN_PROXY:
                default:
                        /* dump proxies */
-                       if (!stats_dump_proxies(sc, htx, uri))
+                       if (!stats_dump_proxies(sc, htx))
                                return 0;
                        break;
                }
@@ -4353,12 +4360,15 @@ static int stats_process_http_post(struct stconn *sc)
 static int stats_send_http_headers(struct stconn *sc, struct htx *htx)
 {
        struct stream *s = __sc_strm(sc);
-       struct uri_auth *uri = s->be->uri_auth;
+       struct uri_auth *uri;
        struct appctx *appctx = __sc_appctx(sc);
        struct show_stat_ctx *ctx = appctx->svcctx;
        struct htx_sl *sl;
        unsigned int flags;
 
+       BUG_ON(!ctx->http_px);
+       uri = ctx->http_px->uri_auth;
+
        flags = (HTX_SL_F_IS_RESP|HTX_SL_F_VER_11|HTX_SL_F_XFER_ENC|HTX_SL_F_XFER_LEN|HTX_SL_F_CHNK);
        sl = htx_add_stline(htx, HTX_BLK_RES_SL, flags, ist("HTTP/1.1"), ist("200"), ist("OK"));
        if (!sl)
@@ -4408,12 +4418,15 @@ static int stats_send_http_redirect(struct stconn *sc, struct htx *htx)
 {
        char scope_txt[STAT_SCOPE_TXT_MAXLEN + sizeof STAT_SCOPE_PATTERN];
        struct stream *s = __sc_strm(sc);
-       struct uri_auth *uri = s->be->uri_auth;
+       struct uri_auth *uri;
        struct appctx *appctx = __sc_appctx(sc);
        struct show_stat_ctx *ctx = appctx->svcctx;
        struct htx_sl *sl;
        unsigned int flags;
 
+       BUG_ON(!ctx->http_px);
+       uri = ctx->http_px->uri_auth;
+
        /* scope_txt = search pattern + search query, ctx->scope_len is always <= STAT_SCOPE_TXT_MAXLEN */
        scope_txt[0] = 0;
        if (ctx->scope_len) {
@@ -4510,7 +4523,7 @@ static void http_stats_io_handler(struct appctx *appctx)
                 * make sure to perform this call on an empty buffer
                 */
                trash_chunk.size = buf_room_for_htx_data(&trash_chunk);
-               if (stats_dump_stat_to_buffer(sc, res_htx, s->be->uri_auth))
+               if (stats_dump_stat_to_buffer(sc, res_htx))
                        appctx->st0 = STAT_HTTP_DONE;
        }
 
@@ -5171,6 +5184,7 @@ static int cli_parse_show_stat(char **args, char *payload, struct appctx *appctx
 
        ctx->scope_str = 0;
        ctx->scope_len = 0;
+       ctx->http_px = NULL; // not under http context
        ctx->flags = STAT_SHNODE | STAT_SHDESC;
 
        if ((strm_li(appctx_strm(appctx))->bind_conf->level & ACCESS_LVL_MASK) >= ACCESS_LVL_OPER)
@@ -5239,7 +5253,7 @@ static int cli_io_handler_dump_info(struct appctx *appctx)
 static int cli_io_handler_dump_stat(struct appctx *appctx)
 {
        trash_chunk = b_make(trash.area, trash.size, 0, 0);
-       return stats_dump_stat_to_buffer(appctx_sc(appctx), NULL, NULL);
+       return stats_dump_stat_to_buffer(appctx_sc(appctx), NULL);
 }
 
 static int cli_io_handler_dump_json_schema(struct appctx *appctx)