feat: support command cas, stats $memc_value

README.markdown

@@ -20,13 +20,15 @@ Table of Contents
     * [replace $memc_key $memc_flags $memc_exptime $memc_value](#replace-memc_key-memc_flags-memc_exptime-memc_value)
     * [append $memc_key $memc_flags $memc_exptime $memc_value](#append-memc_key-memc_flags-memc_exptime-memc_value)
     * [prepend $memc_key $memc_flags $memc_exptime $memc_value](#prepend-memc_key-memc_flags-memc_exptime-memc_value)
+    * [cas $memc_key $memc_flags $memc_exptime $memc_value $memc_unique_token](#cas-memc_key-memc_flags-memc_exptime-memc_value-memc_unique_token)
     * [delete $memc_key](#delete-memc_key)
     * [delete $memc_key $memc_exptime](#delete-memc_key-memc_exptime)
     * [incr $memc_key $memc_value](#incr-memc_key-memc_value)
     * [decr $memc_key $memc_value](#decr-memc_key-memc_value)
     * [flush_all](#flush_all)
     * [flush_all $memc_exptime](#flush_all-memc_exptime)
     * [stats](#stats)
+    * [stats $memc_value](#stats-memc_value)
     * [version](#version)
 * [Directives](#directives)
     * [memc_pass](#memc_pass)
@@ -324,6 +326,13 @@ Similar to the [append command](#append-memc_key-memc_flags-memc_exptime-memc_va
 
 [Back to TOC](#table-of-contents)
 
+cas $memc_key $memc_flags $memc_exptime $memc_value $memc_unique_token
+-------------------------------------------------------
+
+Similar to the [set command](#set-memc_key-memc_flags-memc_exptime-memc_value).
+
+[Back to TOC](#table-of-contents)
+
 delete $memc_key
 ----------------
 
@@ -425,6 +434,28 @@ The raw `stats` command output from the upstream memcached server will be put in
 
 [Back to TOC](#table-of-contents)
 
+stats $memc_value
+-----
+
+Causes the memcached server to output general-purpose statistics and settings
+
+```nginx
+
+   location /foo {
+       set $memc_cmd stats;
+       set $memc_value items;
+       memc_pass 127.0.0.1:11211;
+   }
+```
+
+Returns `200 OK` if the request succeeds, or 502 for `ERROR`, `CLIENT_ERROR`, or `SERVER_ERROR`.
+
+Possible `$memc_value` argument values are `items`, `sizes`, `slabs`, among others.
+
+The raw `stats` command output from the upstream memcached server will be put into the response body. 
+
+[Back to TOC](#table-of-contents)
+
 version
 -------
 
@@ -748,7 +779,7 @@ Some parts of the test suite requires modules [rewrite](http://nginx.org/en/docs
 TODO
 ====
 
-* add support for the memcached commands `cas`, `gets` and `stats $memc_value`.
+* add support for the memcached commands `gets`.
 * add support for the `noreply` option.
 
 [Back to TOC](#table-of-contents)

src/ngx_http_memc_handler.c

@@ -36,6 +36,7 @@ static ngx_str_t  ngx_http_memc_cmd = ngx_string("memc_cmd");
 static ngx_str_t  ngx_http_memc_value = ngx_string("memc_value");
 static ngx_str_t  ngx_http_memc_flags = ngx_string("memc_flags");
 static ngx_str_t  ngx_http_memc_exptime = ngx_string("memc_exptime");
+static ngx_str_t  ngx_http_memc_unique_token = ngx_string("memc_unique_token");
 
 
 static ngx_int_t ngx_http_memc_add_more_variables(ngx_conf_t *cf);
@@ -68,6 +69,7 @@ ngx_http_memc_handler(ngx_http_request_t *r)
     ngx_http_variable_value_t      *value_vv;
     ngx_http_variable_value_t      *flags_vv;
     ngx_http_variable_value_t      *exptime_vv;
+    ngx_http_variable_value_t      *unique_token_vv;
 
     ngx_http_memc_cmd_t             memc_cmd;
     ngx_flag_t                      is_storage_cmd = 0;
@@ -257,9 +259,13 @@ ngx_http_memc_handler(ngx_http_request_t *r)
         u->input_filter_init = ngx_http_memc_empty_filter_init;
         u->input_filter = ngx_http_memc_empty_filter;
 
-    } else if (memc_cmd == ngx_http_memc_cmd_version
-               || memc_cmd == ngx_http_memc_cmd_stats)
-    {
+    } else if (memc_cmd == ngx_http_memc_cmd_stats) {
+        u->create_request = ngx_http_memc_create_stats_cmd_request;
+        u->process_header = ngx_http_memc_process_simple_header;
+
+        u->input_filter_init = ngx_http_memc_empty_filter_init;
+        u->input_filter = ngx_http_memc_empty_filter;
+    } else if (memc_cmd == ngx_http_memc_cmd_version) {
         u->create_request = ngx_http_memc_create_noarg_cmd_request;
         u->process_header = ngx_http_memc_process_simple_header;
 
@@ -344,6 +350,7 @@ ngx_http_memc_handler(ngx_http_request_t *r)
 
     if (is_storage_cmd
         || memc_cmd == ngx_http_memc_cmd_incr
+        || memc_cmd == ngx_http_memc_cmd_stats
         || memc_cmd == ngx_http_memc_cmd_decr)
     {
         value_vv = ngx_http_get_indexed_variable(r, mmcf->value_index);
@@ -376,6 +383,31 @@ ngx_http_memc_handler(ngx_http_request_t *r)
         ctx->memc_value_vv = value_vv;
     }
 
+    if (memc_cmd == ngx_http_memc_cmd_cas) {
+        unique_token_vv = ngx_http_get_indexed_variable(r, mmcf->unique_token_index);
+        if (unique_token_vv == NULL) {
+            return NGX_HTTP_INTERNAL_SERVER_ERROR;
+        }
+
+        if (unique_token_vv->not_found || unique_token_vv->len == 0) {
+            ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
+                          "the \"$memc_unique_token\" variable is required for "
+                          "command \"%V\"", &ctx->cmd_str);
+
+            return NGX_HTTP_BAD_REQUEST;
+        }
+
+        if (!ngx_http_memc_valid_uint32_str(unique_token_vv->data, 
+                                            unique_token_vv->len)) {
+            ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
+                          "variable \"$memc_unique_token\" takes invalid value: %v",
+                          unique_token_vv);
+
+            return NGX_HTTP_BAD_REQUEST;
+        }
+        ctx->memc_unique_token_vv = unique_token_vv;
+    }
+
     rc = ngx_http_read_client_request_body(r, ngx_http_upstream_init);
 
     if (rc == NGX_ERROR || rc > NGX_OK) {
@@ -512,6 +544,11 @@ ngx_http_memc_init(ngx_conf_t *cf)
         return NGX_ERROR;
     }
 
+    mmcf->unique_token_index = ngx_http_memc_add_variable(cf, &ngx_http_memc_unique_token);
+    if (mmcf->unique_token_index == NGX_ERROR) {
+        return NGX_ERROR;
+    }
+
     return ngx_http_memc_add_more_variables(cf);
 }
 

src/ngx_http_memc_module.h

@@ -19,7 +19,7 @@ typedef enum {
     ngx_http_memc_cmd_replace,
     ngx_http_memc_cmd_append,
     ngx_http_memc_cmd_prepend,
-    /* ngx_http_memc_cmd_cas, */
+    ngx_http_memc_cmd_cas,
 
     ngx_http_memc_cmd_get,
     /* ngx_http_memc_cmd_gets, */
@@ -57,6 +57,7 @@ typedef struct {
     ngx_int_t       value_index;
     ngx_int_t       flags_index;
     ngx_int_t       exptime_index;
+    ngx_int_t       unique_token_index;
     ngx_int_t       module_used;
 } ngx_http_memc_main_conf_t;
 
@@ -78,6 +79,7 @@ typedef struct {
     ngx_http_variable_value_t  *memc_key_vv;
     ngx_http_variable_value_t  *memc_flags_vv;
     ngx_http_variable_value_t  *memc_exptime_vv;
+    ngx_http_variable_value_t  *memc_unique_token_vv;
 
     ngx_flag_t                 is_storage_cmd;
 

src/ngx_http_memc_request.c

@@ -31,6 +31,7 @@ ngx_http_memc_create_storage_cmd_request(ngx_http_request_t *r)
     ngx_http_variable_value_t      *flags_vv;
     ngx_http_variable_value_t      *exptime_vv;
     ngx_http_variable_value_t      *memc_value_vv;
+    ngx_http_variable_value_t      *unique_token_vv;
 
     u_char                          bytes_buf[NGX_UINT32_LEN];
 
@@ -124,6 +125,12 @@ ngx_http_memc_create_storage_cmd_request(ngx_http_request_t *r)
         + bytes_len
         + sizeof(CRLF) - 1;
 
+
+    unique_token_vv = ctx->memc_unique_token_vv;
+    if (ctx->cmd == ngx_http_memc_cmd_cas) {
+        len += unique_token_vv->len + sizeof(" ") - 1;
+    }
+
     b = ngx_create_temp_buf(r->pool, len);
     if (b == NULL) {
         return NGX_ERROR;
@@ -182,6 +189,12 @@ ngx_http_memc_create_storage_cmd_request(ngx_http_request_t *r)
 
     b->last = ngx_copy(b->last, bytes_buf, bytes_len);
 
+    /* copy cas unique token */
+    if (ctx->cmd == ngx_http_memc_cmd_cas) {
+        *b->last++ = ' ';
+        b->last = ngx_copy(b->last, unique_token_vv->data, unique_token_vv->len);
+    }
+
     *b->last++ = CR; *b->last++ = LF;
 
     if (memc_value_vv) {
@@ -325,6 +338,53 @@ ngx_http_memc_create_get_cmd_request(ngx_http_request_t *r)
     return NGX_OK;
 }
 
+
+ngx_int_t
+ngx_http_memc_create_stats_cmd_request(ngx_http_request_t *r)
+{
+    size_t                          len;
+    ngx_buf_t                      *b;
+    ngx_http_memc_ctx_t            *ctx;
+    ngx_chain_t                    *cl;
+    ngx_http_variable_value_t      *value_vv;
+
+    ctx = ngx_http_get_module_ctx(r, ngx_http_memc_module);
+
+    len = ctx->cmd_str.len + sizeof(CRLF) - 1;
+
+    value_vv = ctx->memc_value_vv;
+    if (value_vv && value_vv->not_found == 0 && value_vv->len) {
+        len += value_vv->len + sizeof(" ") - 1;
+    }
+
+    b = ngx_create_temp_buf(r->pool, len);
+    if (b == NULL) {
+        return NGX_ERROR;
+    }
+
+    cl = ngx_alloc_chain_link(r->pool);
+    if (cl == NULL) {
+        return NGX_ERROR;
+    }
+
+    cl->buf = b;
+    cl->next = NULL;
+
+    r->upstream->request_bufs = cl;
+
+    b->last = ngx_copy(b->last, ctx->cmd_str.data, ctx->cmd_str.len);
+
+    if (value_vv && value_vv->not_found == 0 && value_vv->len) {
+        *b->last++ = ' ';
+        b->last = ngx_copy(b->last, value_vv->data, value_vv->len);
+    }
+
+    *b->last++ = CR; *b->last++ = LF;
+
+    return NGX_OK;
+}
+
+
 ngx_int_t
 ngx_http_memc_create_noarg_cmd_request(ngx_http_request_t *r)
 {

src/ngx_http_memc_request.h

@@ -16,6 +16,8 @@ ngx_int_t ngx_http_memc_create_storage_cmd_request(ngx_http_request_t *r);
 
 ngx_int_t ngx_http_memc_create_noarg_cmd_request(ngx_http_request_t *r);
 
+ngx_int_t ngx_http_memc_create_stats_cmd_request(ngx_http_request_t *r);
+
 ngx_int_t ngx_http_memc_create_flush_all_cmd_request(ngx_http_request_t *r);
 
 ngx_int_t ngx_http_memc_create_delete_cmd_request(ngx_http_request_t *r);

src/ngx_http_memc_util.c

@@ -27,12 +27,10 @@ ngx_http_memc_parse_cmd(u_char *data, size_t len, ngx_flag_t *is_storage_cmd)
             return ngx_http_memc_cmd_add;
         }
 
-        /*
-        if (ngx_str3cmp(data, 'c', 'a', 's')) {
+        if (ngx_http_memc_strcmp_const(data, "cas") == 0) {
             *is_storage_cmd = 1;
             return ngx_http_memc_cmd_cas;
         }
-        */
 
         if (ngx_http_memc_strcmp_const(data, "get") == 0) {
             return ngx_http_memc_cmd_get;

t/cmd.t

@@ -142,3 +142,69 @@ STORED\r
 get big2
 nice to meet you!"
 
+
+
+=== TEST 9: cas cmd $memc_unique_token variable dont't set
+--- config
+    location /foo {
+        set $memc_cmd "cas";
+        set $memc_key "test";
+        set $memc_value "value";
+        memc_pass 127.0.0.1:$TEST_NGINX_MEMCACHED_PORT;
+    }
+--- request
+    GET /foo
+--- response_body_like: 400 Bad Request
+--- error_code: 400
+
+
+
+=== TEST 10: cas cmd key not exists. memc response NOT_FOUND
+--- config
+    location /main {
+        echo 'flush all';
+        echo_location '/foo?cmd=flush_all';
+
+        echo 'cas foo new value';
+        echo_location '/foo?key=foo&cmd=cas&val=newvalue&token=123';
+    }
+    location /foo {
+        set $memc_cmd $arg_cmd;
+        set $memc_key $arg_key;
+        set $memc_value $arg_val;
+        set $memc_unique_token $arg_token;
+        memc_pass 127.0.0.1:$TEST_NGINX_MEMCACHED_PORT;
+    }
+--- request
+    GET /main
+--- response_body_like
+^flush all
+OK\r
+cas foo new value
+<html>.*?404 Not Found.*$
+
+
+
+=== TEST 10: cas cmd key exists. memc response EXISTS
+--- config
+    location /main {
+        echo 'set foo val ok';
+        echo_location '/foo?cmd=set&val=value&key=foo';
+
+        echo 'cas foo new value';
+        echo_location '/foo?key=foo&cmd=cas&val=newvalue&token=123';
+    }
+    location /foo {
+        set $memc_cmd $arg_cmd;
+        set $memc_key $arg_key;
+        set $memc_value $arg_val;
+        set $memc_unique_token $arg_token;
+        memc_pass 127.0.0.1:$TEST_NGINX_MEMCACHED_PORT;
+    }
+--- request
+    GET /main
+--- response_body eval
+"set foo val ok
+STORED\r
+cas foo new value
+EXISTS\r\n"

t/stats.t

@@ -43,3 +43,16 @@ __DATA__
 --- timeout: 1
 --- error_code: 504
 
+
+
+=== TEST 3: stats slabs
+--- timeout: 5
+--- config
+    location /stats {
+        set $memc_cmd stats;
+        set $memc_value slabs;
+        memc_pass 127.0.0.1:$TEST_NGINX_MEMCACHED_PORT;
+    }
+--- request
+    GET /stats
+--- response_body_like: ^(?:STAT [^\r]*\r\n)*END\r\n$