feat: replace response header (#32)

Author: spacewander

lib/resty/proxy-wasm.lua

@@ -61,7 +61,10 @@ function _M.on_configure(plugin, conf)
         return nil, "bad plugin"
     end
 
-    conf = conf or ""
+    if type(conf) ~= "string" or conf == "" then
+        return nil, "bad conf"
+    end
+
     local plugin_ctx = C.ngx_http_wasm_on_configure(plugin, conf, #conf)
     if plugin_ctx == nil then
         return nil, "failed to run proxy_on_configure"

proxy_wasm_abi.md

@@ -174,7 +174,22 @@ configuration separately because proxy-wasm-rust-sdk still uses it.
   - `i32 (proxy_result_t) call_result`
 
 
-### `proxy_add_map_value`
+### `proxy_set_map_value` (`proxy_replace_header_map_value`)
+
+* params:
+  - `i32 (proxy_map_type_t) map_type`
+  - `i32 (const char*) key_data`
+  - `i32 (size_t) key_size`
+  - `i32 (const char*) value_data`
+  - `i32 (size_t) value_size`
+* returns:
+  - `i32 (proxy_result_t) call_result`
+
+Set or replace the content of key (`key_data`, `key_size`) to the value (`value_data`, `value_size`)
+in a given map (`map_type`).
+
+
+### `proxy_add_map_value` (`proxy_add_header_map_value`)
 
 * params:
   - `i32 (proxy_map_type_t) map_type`

src/http/ngx_http_wasm_api.c

@@ -10,6 +10,17 @@
 #define FFI_NO_REQ_CTX  -100
 #define FFI_BAD_CONTEXT -101
 
+#define must_get_memory(key, log, key_data, key_len) \
+    key = (char *) ngx_wasm_vm.get_memory((log), (key_data), (key_size)); \
+    if (key == NULL) { \
+        return PROXY_RESULT_INVALID_MEMORY_ACCESS; \
+    }
+#define must_get_req(r) \
+    r = ngx_http_wasm_get_req(); \
+    if (r == NULL) { \
+        return PROXY_RESULT_BAD_ARGUMENT; \
+    }
+
 
 static int (*set_resp_header) (ngx_http_request_t *r,
     const char *key_data, size_t key_len, int is_nil,
@@ -388,6 +399,23 @@ int32_t
 proxy_replace_header_map_value(int32_t type, int32_t key_data, int32_t key_size,
                                int32_t data, int32_t size)
 {
+    ngx_int_t                   rc;
+    ngx_log_t                  *log;
+    ngx_http_request_t         *r;
+    char                       *key, *val;
+
+    log = ngx_http_wasm_get_log();
+    must_get_req(r);
+    must_get_memory(key, log, key_data, key_len);
+    must_get_memory(val, log, data, size);
+
+    if (type == PROXY_MAP_TYPE_HTTP_RESPONSE_HEADERS) {
+        rc = ngx_http_wasm_set_resp_header(r, key, key_size, 0, val, size, 1);
+        if (rc != NGX_OK) {
+            return PROXY_RESULT_BAD_ARGUMENT;
+        }
+    }
+
     return PROXY_RESULT_OK;
 }
 
@@ -402,20 +430,9 @@ proxy_add_header_map_value(int32_t type, int32_t key_data, int32_t key_size,
     char                       *key, *val;
 
     log = ngx_http_wasm_get_log();
-    r = ngx_http_wasm_get_req();
-    if (r == NULL) {
-        return PROXY_RESULT_BAD_ARGUMENT;
-    }
-
-    key = (char *) ngx_wasm_vm.get_memory(log, key_data, key_size);
-    if (key == NULL) {
-        return PROXY_RESULT_INVALID_MEMORY_ACCESS;
-    }
-
-    val = (char *) ngx_wasm_vm.get_memory(log, data, size);
-    if (val == NULL) {
-        return PROXY_RESULT_INVALID_MEMORY_ACCESS;
-    }
+    must_get_req(r);
+    must_get_memory(key, log, key_data, key_len);
+    must_get_memory(val, log, data, size);
 
     if (type == PROXY_MAP_TYPE_HTTP_RESPONSE_HEADERS) {
         rc = ngx_http_wasm_set_resp_header(r, key, key_size, 0, val, size, 0);

t/http_header.t

@@ -17,3 +17,35 @@ location /t {
 }
 --- response_headers
 add: foo, bar
+
+
+
+=== TEST 2: response header set
+--- config
+location /t {
+    return 200;
+    header_filter_by_lua_block {
+        local wasm = require("resty.proxy-wasm")
+        local plugin = assert(wasm.load("plugin", "t/testdata/http_header/main.go.wasm"))
+        local ctx = assert(wasm.on_configure(plugin, 'resp_hdr_set'))
+        assert(wasm.on_http_response_headers(ctx))
+    }
+}
+--- response_headers
+add: bar
+
+
+
+=== TEST 3: response header set empty
+--- config
+location /t {
+    return 200;
+    header_filter_by_lua_block {
+        local wasm = require("resty.proxy-wasm")
+        local plugin = assert(wasm.load("plugin", "t/testdata/http_header/main.go.wasm"))
+        local ctx = assert(wasm.on_configure(plugin, 'resp_hdr_set_empty'))
+        assert(wasm.on_http_response_headers(ctx))
+    }
+}
+--- response_headers
+add:

t/log.t

@@ -11,7 +11,7 @@ location /t {
     content_by_lua_block {
         local wasm = require("resty.proxy-wasm")
         local p = wasm.load("plugin", "t/testdata/log/main.go.wasm")
-        wasm.on_configure(p)
+        wasm.on_configure(p, "blah")
     }
 }
 --- grep_error_log eval

t/plugin_lifecycle.t

@@ -191,3 +191,18 @@ location /t {
 }
 --- shutdown_error_log
 failed to mark context 1 as done
+
+
+
+=== TEST 9: empty configure
+--- config
+location /t {
+    content_by_lua_block {
+        local wasm = require("resty.proxy-wasm")
+        local plugin = wasm.load("plugin", "t/testdata/plugin_lifecycle/main.go.wasm")
+        local _, err = wasm.on_configure(plugin, '')
+        ngx.say(err)
+    }
+}
+--- response_body
+bad conf

t/testdata/http_header/main.go

@@ -42,6 +42,10 @@ func (ctx *httpContext) OnHttpResponseHeaders(numHeaders int, endOfStream bool)
 
 	if action == "resp_hdr_add" {
 		proxywasm.AddHttpResponseHeader("add", "bar")
+	} else if action == "resp_hdr_set" {
+		proxywasm.ReplaceHttpResponseHeader("add", "bar")
+	} else if action == "resp_hdr_set_empty" {
+		proxywasm.ReplaceHttpResponseHeader("add", "")
 	}
 
 	return types.ActionContinue