wasm: Add hello world

Signed-off-by: Ryan Northey <ryan@synca.io>

Author: phlax

WORKSPACE

@@ -0,0 +1 @@
+workspace(name = "envoy-modules")

wasm/http-hello-world/BUILD

@@ -0,0 +1,23 @@
+load("@bazel_skylib//lib:selects.bzl", "selects")
+load("@envoy//bazel/wasm:wasm.bzl", "envoy_wasm_cc_binary")
+
+licenses(["notice"])  # Apache 2
+
+exports_files(["module.rst", "module.yaml"])
+
+envoy_wasm_cc_binary(
+    name = "hello.wasm",
+    srcs = ["hello.cc"],
+)
+
+filegroup(
+    name = "files",
+    srcs = glob(["**/*"], exclude = ["module.rst", "module.yaml", "BUILD"]),
+    visibility = ["//visibility:public"],
+)
+
+alias(
+    name = "module",
+    actual = ":hello.wasm",
+    visibility = ["//visibility:public"],
+)

wasm/http-hello-world/hello.cc

@@ -0,0 +1,91 @@
+// NOLINT(namespace-envoy)
+#include <string>
+#include <string_view>
+#include <unordered_map>
+
+#include "proxy_wasm_intrinsics.h"
+
+class ExampleRootContext : public RootContext {
+public:
+  explicit ExampleRootContext(uint32_t id, std::string_view root_id) : RootContext(id, root_id) {}
+
+  bool onStart(size_t) override;
+  bool onConfigure(size_t) override;
+  void onTick() override;
+};
+
+class ExampleContext : public Context {
+public:
+  explicit ExampleContext(uint32_t id, RootContext* root) : Context(id, root) {}
+
+  void onCreate() override;
+  FilterHeadersStatus onRequestHeaders(uint32_t headers, bool end_of_stream) override;
+  FilterDataStatus onRequestBody(size_t body_buffer_length, bool end_of_stream) override;
+  FilterHeadersStatus onResponseHeaders(uint32_t headers, bool end_of_stream) override;
+  FilterDataStatus onResponseBody(size_t body_buffer_length, bool end_of_stream) override;
+  void onDone() override;
+  void onLog() override;
+  void onDelete() override;
+};
+static RegisterContextFactory register_ExampleContext(CONTEXT_FACTORY(ExampleContext),
+                                                      ROOT_FACTORY(ExampleRootContext),
+                                                      "my_root_id");
+
+bool ExampleRootContext::onStart(size_t) {
+  LOG_TRACE("onStart");
+  return true;
+}
+
+bool ExampleRootContext::onConfigure(size_t) {
+  LOG_TRACE("onConfigure");
+  proxy_set_tick_period_milliseconds(1000); // 1 sec
+  return true;
+}
+
+void ExampleRootContext::onTick() { LOG_TRACE("onTick"); }
+
+void ExampleContext::onCreate() { LOG_WARN(std::string("onCreate " + std::to_string(id()))); }
+
+FilterHeadersStatus ExampleContext::onRequestHeaders(uint32_t, bool) {
+  LOG_DEBUG(std::string("onRequestHeaders ") + std::to_string(id()));
+  auto result = getRequestHeaderPairs();
+  auto pairs = result->pairs();
+  LOG_INFO(std::string("headers: ") + std::to_string(pairs.size()));
+  for (auto& p : pairs) {
+    LOG_INFO(std::string(p.first) + std::string(" -> ") + std::string(p.second));
+  }
+  return FilterHeadersStatus::Continue;
+}
+
+FilterHeadersStatus ExampleContext::onResponseHeaders(uint32_t, bool) {
+  LOG_DEBUG(std::string("onResponseHeaders ") + std::to_string(id()));
+  auto result = getResponseHeaderPairs();
+  auto pairs = result->pairs();
+  LOG_INFO(std::string("headers: ") + std::to_string(pairs.size()));
+  for (auto& p : pairs) {
+    LOG_INFO(std::string(p.first) + std::string(" -> ") + std::string(p.second));
+  }
+  addResponseHeader("X-Wasm-custom", "FOO");
+  replaceResponseHeader("content-type", "text/plain; charset=utf-8");
+  removeResponseHeader("content-length");
+  return FilterHeadersStatus::Continue;
+}
+
+FilterDataStatus ExampleContext::onRequestBody(size_t body_buffer_length,
+                                               bool /* end_of_stream */) {
+  auto body = getBufferBytes(WasmBufferType::HttpRequestBody, 0, body_buffer_length);
+  LOG_ERROR(std::string("onRequestBody ") + std::string(body->view()));
+  return FilterDataStatus::Continue;
+}
+
+FilterDataStatus ExampleContext::onResponseBody(size_t body_buffer_length,
+                                                bool /* end_of_stream */) {
+  setBuffer(WasmBufferType::HttpResponseBody, 0, body_buffer_length, "Hello, world\n");
+  return FilterDataStatus::Continue;
+}
+
+void ExampleContext::onDone() { LOG_WARN(std::string("onDone " + std::to_string(id()))); }
+
+void ExampleContext::onLog() { LOG_WARN(std::string("onLog " + std::to_string(id()))); }
+
+void ExampleContext::onDelete() { LOG_WARN(std::string("onDelete " + std::to_string(id()))); }

wasm/http-hello-world/module.rst

@@ -0,0 +1,14 @@
+Download
+--------
+
+
+Running
+-------
+
+
+Configuration
+-------------
+
+
+Building
+--------

wasm/http-hello-world/module.yaml

@@ -0,0 +1,12 @@
+name: wasm-hello-world
+title: Hello world (Wasm)
+description: |
+  Wasm Hello world HTTP filter
+type: wasm
+language: c++
+labels:
+- wasm
+- http
+- hello
+- world
+- c++