Merge branch 'nghttpx-configrevision-api'

doc/nghttpx.h2r

@@ -559,6 +559,9 @@ status
 code
   HTTP status code
 
+Additionally, depending on the API endpoint, ``data`` key may be
+present, and its value contains the API endpoint specific data.
+
 We wrote "normally", since nghttpx may return ordinal HTML response in
 some cases where the error has occurred before reaching API endpoint
 (e.g., header field is too large).
@@ -590,6 +593,23 @@ The one limitation is that only numeric IP address is allowd in
 is used while non numeric hostname is allowed in command-line or
 configuration file is read using :option:`--conf`.
 
+GET /api/v1beta1/configrevision
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+This API returns configuration revision of the current nghttpx.  The
+configuration revision is opaque string, and it changes after each
+reloading by SIGHUP.  With this API, an external application knows
+that whether nghttpx has finished reloading its configuration by
+comparing the configuration revisions between before and after
+reloading.
+
+This API returns response including ``data`` key.  Its value is JSON
+object, and it contains at least the following key:
+
+configRevision
+  The configuration revision of the current nghttpx
+
+
 SEE ALSO
 --------
 

integration-tests/nghttpx_http1_test.go

@@ -974,6 +974,43 @@ backend=127.0.0.1,3011
 	}
 }
 
+// TestH1APIConfigrevision tests configrevision API.
+func TestH1APIConfigrevision(t *testing.T) {
+	st := newServerTesterConnectPort([]string{"-f127.0.0.1,3010;api;no-tls"}, t, func(w http.ResponseWriter, r *http.Request) {
+		t.Fatalf("request should not be forwarded")
+	}, 3010)
+	defer st.Close()
+
+	res, err := st.http1(requestParam{
+		name:   "TestH1APIConfigrevision",
+		path:   "/api/v1beta1/configrevision",
+		method: "GET",
+	})
+	if err != nil {
+		t.Fatalf("Error st.http1() = %v", err)
+	}
+	if got, want := res.status, 200; got != want {
+		t.Errorf("res.status: %v; want = %v", got, want)
+	}
+
+	var apiResp APIResponse
+	d := json.NewDecoder(bytes.NewBuffer(res.body))
+	d.UseNumber()
+	err = d.Decode(&apiResp)
+	if err != nil {
+		t.Fatalf("Error unmarshalling API response: %v", err)
+	}
+	if got, want := apiResp.Status, "Success"; got != want {
+		t.Errorf("apiResp.Status: %v; want %v", got, want)
+	}
+	if got, want := apiResp.Code, 200; got != want {
+		t.Errorf("apiResp.Status: %v; want %v", got, want)
+	}
+	if got, want := apiResp.Data["configRevision"], json.Number("0"); got != want {
+		t.Errorf(`apiResp.Data["configRevision"]: %v %t; want %v`, got, got, want)
+	}
+}
+
 // TestH1APINotFound exercise backendconfig API endpoint routine when
 // API endpoint is not found.
 func TestH1APINotFound(t *testing.T) {

integration-tests/nghttpx_http2_test.go

@@ -1,6 +1,7 @@
 package nghttp2
 
 import (
+	"bytes"
 	"crypto/tls"
 	"encoding/json"
 	"fmt"
@@ -2071,6 +2072,43 @@ backend=127.0.0.1,3011
 	}
 }
 
+// TestH2APIConfigrevision tests configrevision API.
+func TestH2APIConfigrevision(t *testing.T) {
+	st := newServerTesterConnectPort([]string{"-f127.0.0.1,3010;api;no-tls"}, t, func(w http.ResponseWriter, r *http.Request) {
+		t.Fatalf("request should not be forwarded")
+	}, 3010)
+	defer st.Close()
+
+	res, err := st.http2(requestParam{
+		name:   "TestH2APIConfigrevision",
+		path:   "/api/v1beta1/configrevision",
+		method: "GET",
+	})
+	if err != nil {
+		t.Fatalf("Error st.http2() = %v", err)
+	}
+	if got, want := res.status, 200; got != want {
+		t.Errorf("res.status: %v; want = %v", got, want)
+	}
+
+	var apiResp APIResponse
+	d := json.NewDecoder(bytes.NewBuffer(res.body))
+	d.UseNumber()
+	err = d.Decode(&apiResp)
+	if err != nil {
+		t.Fatalf("Error unmarshalling API response: %v", err)
+	}
+	if got, want := apiResp.Status, "Success"; got != want {
+		t.Errorf("apiResp.Status: %v; want %v", got, want)
+	}
+	if got, want := apiResp.Code, 200; got != want {
+		t.Errorf("apiResp.Status: %v; want %v", got, want)
+	}
+	if got, want := apiResp.Data["configRevision"], json.Number("0"); got != want {
+		t.Errorf(`apiResp.Data["configRevision"]: %v %t; want %v`, got, got, want)
+	}
+}
+
 // TestH2APINotFound exercise backendconfig API endpoint routine when
 // API endpoint is not found.
 func TestH2APINotFound(t *testing.T) {

integration-tests/server_tester.go

@@ -801,6 +801,7 @@ func cloneHeader(h http.Header) http.Header {
 func noopHandler(w http.ResponseWriter, r *http.Request) {}
 
 type APIResponse struct {
-	Status string `json:"status,omitempty"`
+	Status string                 `json:"status,omitempty"`
-	Code   int    `json:"code,omitempty"`
+	Code   int                    `json:"code,omitempty"`
+	Data   map[string]interface{} `json:"data,omitempty"`
 }

src/shrpx.cc

@@ -2942,6 +2942,7 @@ void reload_config(WorkerProcess *wp) {
   new_config->daemon = cur_config->daemon;
   // loop is reused, and ev_loop_flags gets ignored
   new_config->ev_loop_flags = cur_config->ev_loop_flags;
+  new_config->config_revision = cur_config->config_revision + 1;
 
   rv = process_options(new_config.get(), suconfig.cmdcfgs);
   if (rv != 0) {

src/shrpx_api_downstream_connection.cc

@@ -33,8 +33,31 @@
 
 namespace shrpx {
 
+namespace {
+// List of API endpoints
+const APIEndpoint apis[] = {
+    APIEndpoint{
+        StringRef::from_lit("/api/v1beta1/backendconfig"), true,
+        (1 << API_METHOD_POST) | (1 << API_METHOD_PUT),
+        &APIDownstreamConnection::handle_backendconfig,
+    },
+    APIEndpoint{
+        StringRef::from_lit("/api/v1beta1/configrevision"), true,
+        (1 << API_METHOD_GET), &APIDownstreamConnection::handle_configrevision,
+    },
+};
+} // namespace
+
+namespace {
+// The method string.  This must be same order of APIMethod.
+constexpr StringRef API_METHOD_STRING[] = {
+    StringRef::from_lit("GET"), StringRef::from_lit("POST"),
+    StringRef::from_lit("PUT"),
+};
+} // namespace
+
 APIDownstreamConnection::APIDownstreamConnection(Worker *worker)
-    : worker_(worker), abandoned_(false) {}
+    : worker_(worker), api_(nullptr), shutdown_read_(false) {}
 
 APIDownstreamConnection::~APIDownstreamConnection() {}
 
@@ -63,8 +86,8 @@ enum {
 };
 
 int APIDownstreamConnection::send_reply(unsigned int http_status,
-                                        int api_status) {
+                                        int api_status, const StringRef &data) {
-  abandoned_ = true;
+  shutdown_read_ = true;
 
   auto upstream = downstream_->get_upstream();
 
@@ -93,7 +116,8 @@ int APIDownstreamConnection::send_reply(unsigned int http_status,
 
   // 3 is the number of digits in http_status, assuming it is 3 digits
   // number.
-  auto buflen = M1.size() + M2.size() + M3.size() + api_status_str.size() + 3;
+  auto buflen = M1.size() + M2.size() + M3.size() + data.size() +
+                api_status_str.size() + 3;
 
   auto buf = make_byte_ref(balloc, buflen);
   auto p = buf.base;
@@ -102,6 +126,7 @@ int APIDownstreamConnection::send_reply(unsigned int http_status,
   p = std::copy(std::begin(api_status_str), std::end(api_status_str), p);
   p = std::copy(std::begin(M2), std::end(M2), p);
   p = util::utos(p, http_status);
+  p = std::copy(std::begin(data), std::end(data), p);
   p = std::copy(std::begin(M3), std::end(M3), p);
 
   buf.len = p - buf.base;
@@ -128,25 +153,68 @@ int APIDownstreamConnection::send_reply(unsigned int http_status,
   return 0;
 }
 
+namespace {
+const APIEndpoint *lookup_api(const StringRef &path) {
+  switch (path.size()) {
+  case 26:
+    switch (path[25]) {
+    case 'g':
+      if (util::streq_l("/api/v1beta1/backendconfi", std::begin(path), 25)) {
+        return &apis[0];
+      }
+      break;
+    }
+    break;
+  case 27:
+    switch (path[26]) {
+    case 'n':
+      if (util::streq_l("/api/v1beta1/configrevisio", std::begin(path), 26)) {
+        return &apis[1];
+      }
+      break;
+    }
+    break;
+  }
+  return nullptr;
+}
+} // namespace
+
 int APIDownstreamConnection::push_request_headers() {
   auto &req = downstream_->request();
-  auto &resp = downstream_->response();
 
   auto path =
       StringRef{std::begin(req.path),
                 std::find(std::begin(req.path), std::end(req.path), '?')};
 
-  if (path != StringRef::from_lit("/api/v1beta1/backendconfig")) {
+  api_ = lookup_api(path);
+
+  if (!api_) {
     send_reply(404, API_FAILURE);
 
     return 0;
   }
 
-  if (req.method != HTTP_POST && req.method != HTTP_PUT) {
+  switch (req.method) {
-    resp.fs.add_header_token(StringRef::from_lit("allow"),
+  case HTTP_GET:
-                             StringRef::from_lit("POST, PUT"), false, -1);
+    if (!(api_->allowed_methods & (1 << API_METHOD_GET))) {
-    send_reply(405, API_FAILURE);
+      error_method_not_allowed();
-
+      return 0;
+    }
+    break;
+  case HTTP_POST:
+    if (!(api_->allowed_methods & (1 << API_METHOD_POST))) {
+      error_method_not_allowed();
+      return 0;
+    }
+    break;
+  case HTTP_PUT:
+    if (!(api_->allowed_methods & (1 << API_METHOD_PUT))) {
+      error_method_not_allowed();
+      return 0;
+    }
+    break;
+  default:
+    error_method_not_allowed();
     return 0;
   }
 
@@ -161,9 +229,42 @@ int APIDownstreamConnection::push_request_headers() {
   return 0;
 }
 
+int APIDownstreamConnection::error_method_not_allowed() {
+  auto &resp = downstream_->response();
+
+  size_t len = 0;
+  for (uint8_t i = 0; i < API_METHOD_MAX; ++i) {
+    if (api_->allowed_methods & (1 << i)) {
+      // The length of method + ", "
+      len += API_METHOD_STRING[i].size() + 2;
+    }
+  }
+
+  assert(len > 0);
+
+  auto &balloc = downstream_->get_block_allocator();
+
+  auto iov = make_byte_ref(balloc, len + 1);
+  auto p = iov.base;
+  for (uint8_t i = 0; i < API_METHOD_MAX; ++i) {
+    if (api_->allowed_methods & (1 << i)) {
+      auto &s = API_METHOD_STRING[i];
+      p = std::copy(std::begin(s), std::end(s), p);
+      p = std::copy_n(", ", 2, p);
+    }
+  }
+
+  p -= 2;
+  *p = '\0';
+
+  resp.fs.add_header_token(StringRef::from_lit("allow"), StringRef{iov.base, p},
+                           false, -1);
+  return send_reply(405, API_FAILURE);
+}
+
 int APIDownstreamConnection::push_upload_data_chunk(const uint8_t *data,
                                                     size_t datalen) {
-  if (abandoned_) {
+  if (shutdown_read_ || !api_->require_body) {
     return 0;
   }
 
@@ -187,10 +288,14 @@ int APIDownstreamConnection::push_upload_data_chunk(const uint8_t *data,
 }
 
 int APIDownstreamConnection::end_upload_data() {
-  if (abandoned_) {
+  if (shutdown_read_) {
     return 0;
   }
 
+  return api_->handler(*this);
+}
+
+int APIDownstreamConnection::handle_backendconfig() {
   auto output = downstream_->get_request_buf();
 
   std::array<struct iovec, 2> iov;
@@ -287,6 +392,25 @@ int APIDownstreamConnection::end_upload_data() {
   return 0;
 }
 
+int APIDownstreamConnection::handle_configrevision() {
+  auto config = get_config();
+  auto &balloc = downstream_->get_block_allocator();
+
+  // Construct the following string:
+  //   ,
+  //   "data":{
+  //     "configRevision": N
+  //   }
+  auto data = concat_string_ref(
+      balloc, StringRef::from_lit(R"(,"data":{"configRevision":)"),
+      util::make_string_ref_uint(balloc, config->config_revision),
+      StringRef::from_lit("}"));
+
+  send_reply(200, API_SUCCESS, data);
+
+  return 0;
+}
+
 void APIDownstreamConnection::pause_read(IOCtrlReason reason) {}
 
 int APIDownstreamConnection::resume_read(IOCtrlReason reason, size_t consumed) {

src/shrpx_api_downstream_connection.h

@@ -26,11 +26,36 @@
 #define SHRPX_API_DOWNSTREAM_CONNECTION_H
 
 #include "shrpx_downstream_connection.h"
+#include "template.h"
+
+using namespace nghttp2;
 
 namespace shrpx {
 
 class Worker;
 
+// If new method is added, don't forget to update API_METHOD_STRING as
+// well.
+enum APIMethod {
+  API_METHOD_GET,
+  API_METHOD_POST,
+  API_METHOD_PUT,
+  API_METHOD_MAX,
+};
+
+class APIDownstreamConnection;
+
+struct APIEndpoint {
+  // Endpoint path.  It must start with "/api/".
+  StringRef path;
+  // true if we evaluate request body.
+  bool require_body;
+  // Allowed methods.  This is bitwise OR of one or more of (1 <<
+  // APIMethod value).
+  uint8_t allowed_methods;
+  std::function<int(APIDownstreamConnection &)> handler;
+};
+
 class APIDownstreamConnection : public DownstreamConnection {
 public:
   APIDownstreamConnection(Worker *worker);
@@ -58,11 +83,21 @@ public:
   get_downstream_addr_group() const;
   virtual DownstreamAddr *get_addr() const;
 
-  int send_reply(unsigned int http_status, int api_status);
+  int send_reply(unsigned int http_status, int api_status,
+                 const StringRef &data = StringRef{});
+  int error_method_not_allowed();
+
+  // Handles backendconfig API request.
+  int handle_backendconfig();
+  // Handles configrevision API request.
+  int handle_configrevision();
 
 private:
   Worker *worker_;
-  bool abandoned_;
+  // This points to the requested APIEndpoint struct.
+  const APIEndpoint *api_;
+  // true if we stop reading request body.
+  bool shutdown_read_;
 };
 
 } // namespace shrpx

src/shrpx_config.h

@@ -850,6 +850,7 @@ struct Config {
         conn{},
         api{},
         dns{},
+        config_revision{0},
         num_worker{0},
         padding{0},
         rlimit_nofile{0},
@@ -883,6 +884,13 @@ struct Config {
   StringRef conf_path;
   StringRef user;
   StringRef mruby_file;
+  // The revision of configuration which is opaque string, and changes
+  // on each configuration reloading.  This does not change on
+  // backendconfig API call.  This value is returned in health check
+  // as "nghttpx-conf-rev" response header field.  The external
+  // program can check this value to know whether reloading has
+  // completed or not.
+  uint64_t config_revision;
   size_t num_worker;
   size_t padding;
   size_t rlimit_nofile;