Merge db0cb30 into 21732b1

lib/resty/wasmx.lua

@@ -15,10 +15,14 @@ ffi.cdef [[
         ngx_str_t       *config;
     } ngx_wasm_filter_t;
 
+    typedef intptr_t                      ngx_int_t;
     typedef unsigned char                 u_char;
     typedef struct ngx_wavm_t             ngx_wasm_vm_t;
     typedef struct ngx_wasm_ops_plan_t    ngx_wasm_plan_t;
 
+    typedef ngx_int_t (*ngx_wasm_host_prop_fn_t)(void *data, ngx_str_t *key,
+        ngx_str_t *value);
+
     ngx_wasm_vm_t *ngx_wasm_ffi_main_vm();
 ]]
 

lib/resty/wasmx/proxy_wasm.lua

@@ -8,9 +8,11 @@ local C = ffi.C
 local ngx = ngx
 local error = error
 local type = type
+local pcall = pcall
 local ffi_gc = ffi.gc
 local ffi_new = ffi.new
 local ffi_str = ffi.string
+local tostring = tostring
 local subsystem = ngx.config.subsystem
 local get_request = wasmx.get_request
 local get_err_ptr = wasmx.get_err_ptr
@@ -38,23 +40,32 @@ local _M = {
 
 if subsystem == "http" then
     ffi.cdef [[
-        int ngx_http_wasm_ffi_plan_new(ngx_wasm_vm_t *vm,
-                                       ngx_wasm_filter_t *filters,
-                                       size_t n_filters,
-                                       ngx_wasm_plan_t **out,
-                                       u_char *err, size_t *errlen);
-        int ngx_http_wasm_ffi_plan_free(ngx_wasm_plan_t *plan);
-        int ngx_http_wasm_ffi_plan_load(ngx_wasm_plan_t *plan);
-        int ngx_http_wasm_ffi_plan_attach(ngx_http_request_t *r,
-                                          ngx_wasm_plan_t *plan,
-                                          unsigned int isolation);
-        int ngx_http_wasm_ffi_start(ngx_http_request_t *r);
-        int ngx_http_wasm_ffi_set_property(ngx_http_request_t *r,
-                                           ngx_str_t *key,
-                                           ngx_str_t *value);
-        int ngx_http_wasm_ffi_get_property(ngx_http_request_t *r,
-                                           ngx_str_t *key,
-                                           ngx_str_t *out);
+        ngx_int_t ngx_http_wasm_ffi_plan_new(ngx_wasm_vm_t *vm,
+                                             ngx_wasm_filter_t *filters,
+                                             size_t n_filters,
+                                             ngx_wasm_plan_t **out,
+                                             u_char *err, size_t *errlen);
+        ngx_int_t ngx_http_wasm_ffi_plan_free(ngx_wasm_plan_t *plan);
+        ngx_int_t ngx_http_wasm_ffi_plan_load(ngx_wasm_plan_t *plan);
+        ngx_int_t ngx_http_wasm_ffi_plan_attach(ngx_http_request_t *r,
+                                                ngx_wasm_plan_t *plan,
+                                                unsigned int isolation);
+        ngx_int_t ngx_http_wasm_ffi_start(ngx_http_request_t *r);
+        ngx_int_t ngx_http_wasm_ffi_set_property(ngx_http_request_t *r,
+                                                 ngx_str_t *key,
+                                                 ngx_str_t *value);
+        ngx_int_t ngx_http_wasm_ffi_get_property(ngx_http_request_t *r,
+                                                 ngx_str_t *key,
+                                                 ngx_str_t *out);
+        ngx_int_t ngx_http_wasm_ffi_set_host_property(ngx_http_request_t *r,
+                                                      ngx_str_t *key,
+                                                      ngx_str_t *value,
+                                                      unsigned is_const,
+                                                      unsigned retrieve);
+        ngx_int_t ngx_http_wasm_ffi_set_property_setter(ngx_http_request_t *r,
+                                                        ngx_wasm_host_prop_fn_t fn);
+        ngx_int_t ngx_http_wasm_ffi_set_property_getter(ngx_http_request_t *r,
+                                                        ngx_wasm_host_prop_fn_t fn);
     ]]
 
 else
@@ -229,7 +240,7 @@ function _M.set_property(key, value)
         error("key must be a string", 2)
     end
 
-    if type(value) ~= "string" then
+    if value ~= nil and type(value) ~= "string" then
         error("value must be a string", 2)
     end
 
@@ -238,8 +249,14 @@ function _M.set_property(key, value)
         error("no request found", 2)
     end
 
-    local ckey = ffi_new("ngx_str_t", { data = key, len = #key })
-    local cvalue = ffi_new("ngx_str_t", { data = value, len = #value })
+    local ckey = ffi_new("ngx_str_t", {
+        data = key,
+        len = #key
+    })
+    local cvalue = ffi_new("ngx_str_t", {
+        data = value,
+        len = value and #value or 0
+    })
 
     local rc = C.ngx_http_wasm_ffi_set_property(r, ckey, cvalue)
     if rc == FFI_ERROR then
@@ -280,4 +297,167 @@ function _M.get_property(key)
 end
 
 
+do
+    -- LuaJIT C callbacks are a limited resource:
+    -- We can't create one of these on each request,
+    -- so we prepare these wrappers, which in turn call a Lua function.
+    local lua_prop_setter
+    local lua_prop_getter
+    local c_prop_setter
+    local c_prop_getter
+
+
+    local function update_cvalue(cvalue, lvalue)
+        if lvalue == nil then
+            cvalue.data = nil
+            cvalue.len = 0
+            return
+        end
+
+        local value = tostring(lvalue)
+        cvalue.data = value
+        cvalue.len = #value
+    end
+
+
+    local function jit_wrap(fn)
+        return function(r, ckey, cvalue)
+            jit.off()
+            local rc = fn(r, ckey, cvalue)
+            jit.on()
+            return rc
+        end
+    end
+
+
+    c_prop_setter = ffi.cast("ngx_wasm_host_prop_fn_t",
+                             jit_wrap(function(r, ckey, cvalue)
+        local lkey = ffi_str(ckey.data, ckey.len)
+        local lval
+        if cvalue.data ~= nil then
+            lval = ffi_str(cvalue.data, cvalue.len)
+        end
+
+        local pok, ok, lvalue, is_const = pcall(lua_prop_setter, lkey, lval)
+        if not pok then
+            ngx.log(ngx.ERR, "error setting property from Lua: ", ok)
+            return FFI_ERROR
+        end
+
+        if not ok then
+            local err = lvalue or "unknown error"
+            ngx.log(ngx.ERR, "error setting property: ", err)
+            return FFI_ERROR
+        end
+
+        update_cvalue(cvalue, lvalue)
+
+        return C.ngx_http_wasm_ffi_set_host_property(r, ckey, cvalue,
+                                                     is_const and 1 or 0,
+                                                     0)
+    end))
+
+
+    c_prop_getter = ffi.cast("ngx_wasm_host_prop_fn_t",
+                             jit_wrap(function(r, ckey, cvalue)
+        local lkey = ffi_str(ckey.data, ckey.len)
+
+        local pok, ok, lvalue, is_const = pcall(lua_prop_getter, lkey)
+        if not pok then
+            ngx.log(ngx.ERR, "error getting property from Lua: ", ok)
+            return FFI_ERROR
+        end
+
+        if not ok then
+            if lvalue then
+                ngx.log(ngx.ERR, "error setting property: ", lvalue)
+                return FFI_ERROR
+            end
+
+            return FFI_DECLINED
+        end
+
+        update_cvalue(cvalue, lvalue)
+
+        local rc = C.ngx_http_wasm_ffi_set_host_property(r, ckey, cvalue,
+                                                   is_const and 1 or 0,
+                                                   1)
+        if rc == FFI_OK and lvalue == nil then
+            return FFI_DECLINED
+        end
+
+        return rc
+    end))
+
+
+    ---
+    -- Define a setter function for host-managed properties.
+    --
+    -- @param setter The setter function is the handler for updating properties.
+    -- Its type signature is `function(string, string): boolean, string`,
+    -- where the inputs are the property key and value and the results are:
+    -- * `truthy` - success setting the property
+    -- * `truthy, value` - success, cache property value (useful if hosts
+    --   sets only a setter but not a getter)
+    -- * `truthy, value, truthy` - success, constant property value: further
+    --   requests to the same property during a request are cached by
+    --   ngx_wasm_module and do not invoke the Lua getter.
+    -- * `falsy, err` - failure, and an optional error message
+    -- @return true on success setting the getter, or nil and an error message.
+    function _M.set_property_setter(setter)
+        if type(setter) ~= "function" then
+            error("setter must be a function", 2)
+        end
+
+        local r = get_request()
+        if not r then
+            error("no request found", 2)
+        end
+
+        lua_prop_setter = setter
+
+        local rc = C.ngx_http_wasm_ffi_set_property_setter(r, c_prop_setter)
+        if rc == FFI_OK then
+            return true
+        end
+
+        return nil, "could not set property setter"
+    end
+
+
+    ---
+    -- Define a getter function for host-managed properties.
+    --
+    -- @param getter The getter function is the handler for resolving properties.
+    -- Its type signature is `function(string): boolean, string, boolean`,
+    -- where the input is the property key and the results are:
+    -- * `truthy, value` - success, property value
+    -- * `truthy, value, truthy` - success, constant property value: further
+    --   requests to the same property during a request are cached by
+    --   ngx_wasm_module and do not invoke the Lua getter.
+    -- * `falsy` - property not found
+    -- * `falsy, err` - failure, error message
+    -- @return true on success setting the getter, or nil and an error message.
+    function _M.set_property_getter(getter)
+        if type(getter) ~= "function" then
+            error("getter must be a function", 2)
+        end
+
+        local r = get_request()
+        if not r then
+            error("no request found", 2)
+        end
+
+        lua_prop_getter = getter
+
+        local rc = C.ngx_http_wasm_ffi_set_property_getter(r, c_prop_getter)
+        if rc == FFI_OK then
+            return true
+        end
+
+        return nil, "could not set property getter"
+    end
+end
+
+
 return _M

src/common/lua/ngx_wasm_lua_ffi.c

@@ -180,6 +180,21 @@ ngx_http_wasm_ffi_start(ngx_http_request_t *r)
 }
 
 
+static ngx_inline ngx_proxy_wasm_ctx_t *
+get_pwctx(ngx_http_request_t *r)
+{
+    ngx_http_wasm_req_ctx_t  *rctx;
+
+    if (ngx_http_wasm_rctx(r, &rctx) != NGX_OK) {
+        return NULL;
+    }
+
+    return ngx_proxy_wasm_ctx(NULL, 0,
+                              NGX_PROXY_WASM_ISOLATION_STREAM,
+                              &ngx_http_proxy_wasm, rctx);
+}
+
+
 ngx_int_t
 ngx_http_wasm_ffi_set_property(ngx_http_request_t *r,
     ngx_str_t *key, ngx_str_t *value)
@@ -226,4 +241,47 @@ ngx_http_wasm_ffi_get_property(ngx_http_request_t *r,
 
     return ngx_proxy_wasm_properties_get(pwctx, key, value);
 }
+
+
+ngx_int_t
+ngx_http_wasm_ffi_set_host_property(ngx_http_request_t *r,
+    ngx_str_t *key, ngx_str_t *value, unsigned is_const, unsigned retrieve)
+{
+    ngx_proxy_wasm_ctx_t  *pwctx = get_pwctx(r);
+
+    if (pwctx == NULL) {
+        return NGX_ERROR;
+    }
+
+    return ngx_proxy_wasm_properties_set_host(pwctx, key, value, is_const,
+                                              retrieve);
+}
+
+
+ngx_int_t
+ngx_http_wasm_ffi_set_property_setter(ngx_http_request_t *r,
+    ngx_wasm_host_prop_fn_t fn)
+{
+    ngx_proxy_wasm_ctx_t  *pwctx = get_pwctx(r);
+
+    if (pwctx == NULL) {
+        return NGX_ERROR;
+    }
+
+    return ngx_proxy_wasm_properties_set_host_prop_setter(pwctx, fn, r);
+}
+
+
+ngx_int_t
+ngx_http_wasm_ffi_set_property_getter(ngx_http_request_t *r,
+    ngx_wasm_host_prop_fn_t fn)
+{
+    ngx_proxy_wasm_ctx_t  *pwctx = get_pwctx(r);
+
+    if (pwctx == NULL) {
+        return NGX_ERROR;
+    }
+
+    return ngx_proxy_wasm_properties_set_host_prop_getter(pwctx, fn, r);
+}
 #endif

src/common/lua/ngx_wasm_lua_ffi.h

@@ -33,6 +33,12 @@ ngx_int_t ngx_http_wasm_ffi_set_property(ngx_http_request_t *r,
     ngx_str_t *key, ngx_str_t *value);
 ngx_int_t ngx_http_wasm_ffi_get_property(ngx_http_request_t *r,
     ngx_str_t *key, ngx_str_t *value);
+ngx_int_t ngx_http_wasm_ffi_set_host_property(ngx_http_request_t *r,
+    ngx_str_t *key, ngx_str_t *value, unsigned is_const, unsigned retrieve);
+ngx_int_t ngx_http_wasm_ffi_set_property_setter(ngx_http_request_t *r,
+    ngx_wasm_host_prop_fn_t fn);
+ngx_int_t ngx_http_wasm_ffi_set_property_getter(ngx_http_request_t *r,
+    ngx_wasm_host_prop_fn_t fn);
 #endif
 
 

src/common/proxy_wasm/ngx_proxy_wasm.h

@@ -166,6 +166,9 @@ typedef struct ngx_http_proxy_wasm_dispatch_s  ngx_http_proxy_wasm_dispatch_t;
 
 typedef ngx_str_t  ngx_proxy_wasm_marshalled_map_t;
 
+typedef ngx_int_t (*ngx_wasm_host_prop_fn_t)(void *data, ngx_str_t *key,
+    ngx_str_t *value);
+
 
 typedef struct {
     ngx_queue_t                        busy;
@@ -245,10 +248,14 @@ struct ngx_proxy_wasm_ctx_s {
     ngx_uint_t                         call_code;
     ngx_uint_t                         response_code;
 
-    /* host properties rbtree */
+    /* host properties */
 
     ngx_rbtree_t                       host_props_tree;
     ngx_rbtree_node_t                  host_props_sentinel;
+    ngx_wasm_host_prop_fn_t            host_prop_getter;
+    ngx_wasm_host_prop_fn_t            host_prop_setter;
+    void                              *host_prop_getter_data;
+    void                              *host_prop_setter_data;
 
     /* flags */