[WIP] feat(proxy-wasm/metrics) counters and gauges

config

@@ -141,7 +141,8 @@ NGX_WASMX_DEPS="\
     $ngx_addon_dir/src/common/proxy_wasm/ngx_proxy_wasm_properties.h \
     $ngx_addon_dir/src/common/shm/ngx_wasm_shm.h \
     $ngx_addon_dir/src/common/shm/ngx_wasm_shm_kv.h \
-    $ngx_addon_dir/src/common/shm/ngx_wasm_shm_queue.h"
+    $ngx_addon_dir/src/common/shm/ngx_wasm_shm_queue.h \
+    $ngx_addon_dir/src/common/ngx_wa_metrics.h"
 
 NGX_WASMX_SRCS="\
     $ngx_addon_dir/src/ngx_wasmx.c \
@@ -155,7 +156,8 @@ NGX_WASMX_SRCS="\
     $ngx_addon_dir/src/common/proxy_wasm/ngx_proxy_wasm_util.c \
     $ngx_addon_dir/src/common/shm/ngx_wasm_shm.c \
     $ngx_addon_dir/src/common/shm/ngx_wasm_shm_kv.c \
-    $ngx_addon_dir/src/common/shm/ngx_wasm_shm_queue.c"
+    $ngx_addon_dir/src/common/shm/ngx_wasm_shm_queue.c \
+    $ngx_addon_dir/src/common/ngx_wa_metrics.c"
 
 # wasm
 

docs/DIRECTIVES.md

@@ -16,6 +16,7 @@ By alphabetical order:
 - [resolver_timeout](#resolver_timeout)
 - [shm_kv](#shm_kv)
 - [shm_queue](#shm_queue)
+- [slab_size](#slab_size)
 - [socket_buffer_size](#socket_buffer_size)
 - [socket_buffer_reuse](#socket_buffer_reuse)
 - [socket_connect_timeout](#socket_connect_timeout)
@@ -57,6 +58,8 @@ By context:
     - [tls_trusted_certificate](#tls_trusted_certificate)
     - [tls_verify_cert](#tls_verify_cert)
     - [tls_verify_host](#tls_verify_host)
+    - `metrics{}`
+        - [slab_size](#slab_size)
     - `wasmtime{}`
         - [cache_config](#cache-config)
         - [flag](#flag)
@@ -525,6 +528,19 @@ policy, and writes will fail when the allocated memory slab is full.
 
 [Back to TOC](#directives)
 
+shm_queue
+---------
+
+**usage**    | `slab_size <size>;`
+------------:|:----------------------------------------------------------------
+**contexts** | `metrics{}`
+**default**  | `12m`
+**example**  | `slab_size 5m;`
+
+Set the `size` of the shared memory slab dedicated to metrics storage.
+
+[Back to TOC](#directives)
+
 socket_buffer_reuse
 -------------------
 

docs/PROXY_WASM.md

@@ -536,10 +536,10 @@ SDK ABI `0.2.1`) and their present status in ngx_wasm_module:
 `proxy_enqueue_shared_queue`          | :heavy_check_mark:  | No automatic eviction mechanism if the queue is full.
 `proxy_resolve_shared_queue`          | :x:                 |
 *Stats/metrics*                       |                     |
-`proxy_define_metric`                 | :x:                 |
-`proxy_get_metric`                    | :x:                 |
-`proxy_record_metric`                 | :x:                 |
-`proxy_increment_metric`              | :x:                 |
+`proxy_define_metric`                 | :heavy_check_mark:  | Support for histograms NYI.
+`proxy_get_metric`                    | :heavy_check_mark:  |
+`proxy_record_metric`                 | :heavy_check_mark:  |
+`proxy_increment_metric`              | :heavy_check_mark:  |
 *Custom extension points*             |                     |
 `proxy_call_foreign_function`         | :x:                 |