Add implementation for new ABI proxy_log_destination

vikaschoudhary16 · vikaschoudhary16 · commit c0027204e81f · 2023-03-27T11:03:15.000+05:30
diff --git a/include/proxy-wasm/exports.h b/include/proxy-wasm/exports.h
@@ -67,6 +67,7 @@ namespace exports {
 Word get_configuration(Word value_ptr_ptr, Word value_size_ptr);
 Word get_status(Word code_ptr, Word value_ptr_ptr, Word value_size_ptr);
 Word log(Word level, Word address, Word size);
+Word log_destination(Word dest, Word dest_size, Word level, Word address, Word size);
 Word get_log_level(Word result_level_uint32_ptr);
 Word get_property(Word path_ptr, Word path_size, Word value_ptr_ptr, Word value_size_ptr);
 Word set_property(Word key_ptr, Word key_size, Word value_ptr, Word value_size);
@@ -152,18 +153,19 @@ void emscripten_notify_memory_growth(Word);
 // Support for embedders, not exported to Wasm.
 
 #define FOR_ALL_HOST_FUNCTIONS(_f)                                                                 \
-  _f(log) _f(get_status) _f(set_property) _f(get_property) _f(send_local_response)                 \
-      _f(get_shared_data) _f(set_shared_data) _f(register_shared_queue) _f(resolve_shared_queue)   \
-          _f(dequeue_shared_queue) _f(enqueue_shared_queue) _f(get_header_map_value)               \
-              _f(add_header_map_value) _f(replace_header_map_value) _f(remove_header_map_value)    \
-                  _f(get_header_map_pairs) _f(set_header_map_pairs) _f(get_header_map_size)        \
-                      _f(get_buffer_status) _f(get_buffer_bytes) _f(set_buffer_bytes)              \
-                          _f(http_call) _f(grpc_call) _f(grpc_stream) _f(grpc_close)               \
-                              _f(grpc_cancel) _f(grpc_send) _f(set_tick_period_milliseconds)       \
-                                  _f(get_current_time_nanoseconds) _f(define_metric)               \
-                                      _f(increment_metric) _f(record_metric) _f(get_metric)        \
-                                          _f(set_effective_context) _f(done)                       \
-                                              _f(call_foreign_function)
+  _f(log) _f(log_destination) _f(get_status) _f(set_property) _f(get_property)                     \
+      _f(send_local_response) _f(get_shared_data) _f(set_shared_data) _f(register_shared_queue)    \
+          _f(resolve_shared_queue) _f(dequeue_shared_queue) _f(enqueue_shared_queue)               \
+              _f(get_header_map_value) _f(add_header_map_value) _f(replace_header_map_value)       \
+                  _f(remove_header_map_value) _f(get_header_map_pairs) _f(set_header_map_pairs)    \
+                      _f(get_header_map_size) _f(get_buffer_status) _f(get_buffer_bytes)           \
+                          _f(set_buffer_bytes) _f(http_call) _f(grpc_call) _f(grpc_stream)         \
+                              _f(grpc_close) _f(grpc_cancel) _f(grpc_send)                         \
+                                  _f(set_tick_period_milliseconds)                                 \
+                                      _f(get_current_time_nanoseconds) _f(define_metric)           \
+                                          _f(increment_metric) _f(record_metric) _f(get_metric)    \
+                                              _f(set_effective_context) _f(done)                   \
+                                                  _f(call_foreign_function)
 
 #define FOR_ALL_HOST_FUNCTIONS_ABI_SPECIFIC(_f)                                                    \
   _f(get_configuration) _f(continue_request) _f(continue_response) _f(clear_route_cache)           \
diff --git a/include/proxy-wasm/wasm.h b/include/proxy-wasm/wasm.h
@@ -51,6 +51,7 @@ class WasmBase : public std::enable_shared_from_this<WasmBase> {
   WasmBase(std::unique_ptr<WasmVm> wasm_vm, std::string_view vm_id,
            std::string_view vm_configuration, std::string_view vm_key,
            std::unordered_map<std::string, std::string> envs,
+           std::unordered_map<std::string, std::string> log_dest,
            AllowedCapabilitiesMap allowed_capabilities);
   WasmBase(const std::shared_ptr<WasmHandleBase> &base_wasm_handle, const WasmVmFactory &factory);
   virtual ~WasmBase();
@@ -136,6 +137,9 @@ class WasmBase : public std::enable_shared_from_this<WasmBase> {
   AbiVersion abiVersion() const { return abi_version_; }
 
   const std::unordered_map<std::string, std::string> &envs() { return envs_; }
+  const std::unordered_map<std::string, std::string> &log_destinations() {
+    return log_destinations_;
+  }
 
   // Called to raise the flag which indicates that the context should stop iteration regardless of
   // returned filter status from Proxy-Wasm extensions. For example, we ignore
@@ -222,7 +226,7 @@ class WasmBase : public std::enable_shared_from_this<WasmBase> {
   std::unique_ptr<ShutdownHandle> shutdown_handle_;
   std::unordered_map<std::string, std::string>
       envs_; // environment variables passed through wasi.environ_get
-
+  std::unordered_map<std::string, std::string> log_destinations_;
   WasmCallVoid<0> _initialize_; /* WASI reactor (Emscripten v1.39.17+, Rust nightly) */
   WasmCallVoid<0> _start_;      /* WASI command (Emscripten v1.39.0+, TinyGo) */
 
@@ -394,7 +398,7 @@ inline void *WasmBase::allocMemory(uint64_t size, uint64_t *address) {
   }
   wasm_vm_->setRestrictedCallback(
       true, {// logging (Proxy-Wasm)
-             "env.proxy_log",
+             "env.proxy_log", "env.proxy_log_destination",
              // logging (stdout/stderr)
              "wasi_unstable.fd_write", "wasi_snapshot_preview1.fd_write",
              // time
diff --git a/src/exports.cc b/src/exports.cc
@@ -19,6 +19,8 @@
 
 #include <openssl/rand.h>
 
+#include <fstream>
+#include <iostream>
 #include <utility>
 
 namespace proxy_wasm {
@@ -916,6 +918,41 @@ Word log(Word level, Word address, Word size) {
   return context->log(level, message.value());
 }
 
+Word log_destination(Word destination, Word dest_size, Word level, Word address, Word size) {
+  if (level > static_cast<uint64_t>(LogLevel::Max)) {
+    return WasmResult::BadArgument;
+  }
+  auto *context = contextOrEffectiveContext();
+  const auto &log_destinations = context->wasm()->log_destinations();
+
+  auto message = context->wasmVm()->getMemory(address, size);
+  if (!message) {
+    return WasmResult::InvalidMemoryAccess;
+  }
+  auto dest = context->wasmVm()->getMemory(destination, dest_size);
+  if (!dest) {
+    return WasmResult::InvalidMemoryAccess;
+  }
+  context->log(level, dest.value());
+  // iterate over log_destinations map to check if dest
+  // destination requested by plugin exists
+  for (const auto &e : log_destinations) {
+    if (e.first == dest.value()) {
+      // write message to the file which is the value of the key if it exists
+      std::ofstream log_file;
+      log_file.open(e.second, std::ios::out | std::ios_base::app);
+      if (!log_file) {
+        return WasmResult::InvalidMemoryAccess;
+      }
+      log_file << message.value() << std::endl;
+      log_file.close();
+      return WasmResult::Ok;
+    }
+  }
+  // As a fallback, write to the default log destination.
+  return context->log(level, message.value());
+}
+
 Word get_log_level(Word result_level_uint32_ptr) {
   auto *context = contextOrEffectiveContext();
   uint32_t level = context->getLogLevel();
diff --git a/src/wasm.cc b/src/wasm.cc
@@ -190,6 +190,7 @@ WasmBase::WasmBase(const std::shared_ptr<WasmHandleBase> &base_wasm_handle,
       vm_id_(base_wasm_handle->wasm()->vm_id_), vm_key_(base_wasm_handle->wasm()->vm_key_),
       started_from_(base_wasm_handle->wasm()->wasm_vm()->cloneable()),
       envs_(base_wasm_handle->wasm()->envs()),
+      log_destinations_(base_wasm_handle->wasm()->log_destinations()),
       allowed_capabilities_(base_wasm_handle->wasm()->allowed_capabilities_),
       base_wasm_handle_(base_wasm_handle) {
   if (started_from_ != Cloneable::NotCloneable) {
@@ -207,9 +208,11 @@ WasmBase::WasmBase(const std::shared_ptr<WasmHandleBase> &base_wasm_handle,
 WasmBase::WasmBase(std::unique_ptr<WasmVm> wasm_vm, std::string_view vm_id,
                    std::string_view vm_configuration, std::string_view vm_key,
                    std::unordered_map<std::string, std::string> envs,
+                   std::unordered_map<std::string, std::string> log_dest,
                    AllowedCapabilitiesMap allowed_capabilities)
     : vm_id_(std::string(vm_id)), vm_key_(std::string(vm_key)), wasm_vm_(std::move(wasm_vm)),
-      envs_(std::move(envs)), allowed_capabilities_(std::move(allowed_capabilities)),
+      envs_(std::move(envs)), log_destinations_(std::move(log_dest)),
+      allowed_capabilities_(std::move(allowed_capabilities)),
       vm_configuration_(std::string(vm_configuration)), vm_id_handle_(getVmIdHandle(vm_id)) {
   if (!wasm_vm_) {
     failed_ = FailState::UnableToCreateVm;
@@ -358,7 +361,7 @@ void WasmBase::startVm(ContextBase *root_context) {
   // wasi_snapshot_preview1.clock_time_get
   wasm_vm_->setRestrictedCallback(
       true, {// logging (Proxy-Wasm)
-             "env.proxy_log",
+             "env.proxy_log", "env.proxy_log_destination",
              // logging (stdout/stderr)
              "wasi_unstable.fd_write", "wasi_snapshot_preview1.fd_write",
              // args
diff --git a/test/utility.h b/test/utility.h
@@ -140,7 +140,7 @@ class TestWasm : public WasmBase {
   TestWasm(std::unique_ptr<WasmVm> wasm_vm, std::unordered_map<std::string, std::string> envs = {},
            std::string_view vm_id = "", std::string_view vm_configuration = "",
            std::string_view vm_key = "")
-      : WasmBase(std::move(wasm_vm), vm_id, vm_configuration, vm_key, std::move(envs), {}) {}
+      : WasmBase(std::move(wasm_vm), vm_id, vm_configuration, vm_key, std::move(envs), {}, {}) {}
 
   TestWasm(const std::shared_ptr<WasmHandleBase> &base_wasm_handle, const WasmVmFactory &factory)
       : WasmBase(base_wasm_handle, factory) {}
diff --git a/test/wasm_test.cc b/test/wasm_test.cc
@@ -14,6 +14,7 @@
 
 #include "include/proxy-wasm/wasm.h"
 
+#include <iostream>
 #include <unordered_set>
 
 #include "gtest/gtest.h"
@@ -43,9 +44,9 @@ TEST_P(TestVm, GetOrCreateThreadLocalWasmFailCallbacks) {
   // Define callbacks.
   WasmHandleFactory wasm_handle_factory =
       [this, vm_id, vm_config](std::string_view vm_key) -> std::shared_ptr<WasmHandleBase> {
-    auto base_wasm = std::make_shared<WasmBase>(newVm(), vm_id, vm_config, vm_key,
-                                                std::unordered_map<std::string, std::string>{},
-                                                AllowedCapabilitiesMap{});
+    auto base_wasm = std::make_shared<WasmBase>(
+        newVm(), vm_id, vm_config, vm_key, std::unordered_map<std::string, std::string>{},
+        std::unordered_map<std::string, std::string>{}, AllowedCapabilitiesMap{});
     return std::make_shared<WasmHandleBase>(base_wasm);
   };
 
@@ -171,7 +172,6 @@ TEST_P(TestVm, AlwaysApplyCanary) {
   // For each create Wasm, canary should be done.
   EXPECT_EQ(canary_count, 1);
 
-  std::unordered_set<std::shared_ptr<WasmHandleBase>> reference_holder;
 
   for (const auto &root_id : root_ids) {
     for (const auto &vm_id : vm_ids) {
@@ -209,7 +209,6 @@ TEST_P(TestVm, AlwaysApplyCanary) {
             // Keep the reference of wasm_handle_comp in order to utilize the WasmHandleBase
             // cache of createWasm. If we don't keep the reference, WasmHandleBase and VM will be
             // destroyed for each iteration.
-            reference_holder.insert(wasm_handle_comp);
 
             EXPECT_TRUE(TestContext::isGlobalLogged("onConfigure: " + root_id));
 
