Partially remove dependency on folly async

Summary:
This change isolates the usage of folly async from Flipper. Is now self-contained in Flipper Folly schedulers.

Users of Flipper can decide not to use the types defined in that header and implement their own.

NOTE: changes are minimal, we are just replacing direct calls to folly event base with a scheduler which simply relays this on to folly.

Reviewed By: fabiomassimo

Differential Revision: D36626483

fbshipit-source-id: add0241caf4af0aa5c3b5c2e7efc2e725f5400ab

xplat/Flipper/FlipperClient.cpp

@@ -8,6 +8,7 @@
 #include "FlipperClient.h"
 #include <fstream>
 #include <iostream>
+#include <sstream>
 #include <stdexcept>
 #include <vector>
 #include "ConnectionContextStore.h"

xplat/Flipper/FlipperClient.h

@@ -8,6 +8,7 @@
 #pragma once
 
 #include <map>
+#include <memory>
 #include <mutex>
 #include <vector>
 #include "FlipperCertificateProvider.h"

xplat/Flipper/FlipperConnectionManagerImpl.cpp

@@ -95,8 +95,8 @@ FlipperConnectionManagerImpl::FlipperConnectionManagerImpl(
       securePort(config.securePort),
       altInsecurePort(config.altInsecurePort),
       altSecurePort(config.altSecurePort),
-      flipperEventBase_(config.callbackWorker),
-      connectionEventBase_(config.connectionWorker),
+      flipperScheduler_(config.callbackWorker),
+      connectionScheduler_(config.connectionWorker),
       contextStore_(contextStore),
       implWrapper_(std::make_shared<FlipperConnectionManagerWrapper>(this)) {
   CHECK_THROW(config.callbackWorker, std::invalid_argument);
@@ -131,13 +131,10 @@ void FlipperConnectionManagerImpl::start() {
 
   auto step = flipperState_->start("Start connection thread");
 
-  folly::makeFuture()
-      .via(flipperEventBase_->getEventBase())
-      .delayed(std::chrono::milliseconds(0))
-      .thenValue([this, step](auto&&) {
-        step->complete();
-        startSync();
-      });
+  flipperScheduler_->schedule([this, step]() {
+    step->complete();
+    startSync();
+  });
 }
 
 void FlipperConnectionManagerImpl::startSync() {
@@ -210,7 +207,7 @@ bool FlipperConnectionManagerImpl::connectAndExchangeCertificate() {
   payload->medium = medium;
 
   auto newClient = FlipperSocketProvider::socketCreate(
-      endpoint, std::move(payload), connectionEventBase_);
+      endpoint, std::move(payload), flipperScheduler_);
   newClient->setEventHandler(ConnectionEvents(implWrapper_));
 
   auto connectingInsecurely = flipperState_->start("Connect insecurely");
@@ -259,7 +256,7 @@ bool FlipperConnectionManagerImpl::connectSecurely() {
   payload->csr_path = contextStore_->getCertificateDirectoryPath().c_str();
 
   auto newClient = FlipperSocketProvider::socketCreate(
-      endpoint, std::move(payload), connectionEventBase_, contextStore_.get());
+      endpoint, std::move(payload), connectionScheduler_, contextStore_.get());
   newClient->setEventHandler(ConnectionEvents(implWrapper_));
   newClient->setMessageHandler([this](const std::string& msg) {
     std::unique_ptr<FireAndForgetBasedFlipperResponder> responder;
@@ -294,10 +291,8 @@ void FlipperConnectionManagerImpl::reconnect() {
     log("Not started");
     return;
   }
-  folly::makeFuture()
-      .via(flipperEventBase_->getEventBase())
-      .delayed(std::chrono::seconds(reconnectIntervalSeconds))
-      .thenValue([this](auto&&) { startSync(); });
+  flipperScheduler_->scheduleAfter(
+      [this]() { startSync(); }, reconnectIntervalSeconds * 1000.0f);
 }
 
 void FlipperConnectionManagerImpl::stop() {
@@ -325,7 +320,7 @@ void FlipperConnectionManagerImpl::setCallbacks(Callbacks* callbacks) {
 }
 
 void FlipperConnectionManagerImpl::sendMessage(const folly::dynamic& message) {
-  flipperEventBase_->add([this, message]() {
+  flipperScheduler_->schedule([this, message]() {
     try {
       if (client_) {
         client_->send(message, []() {});
@@ -457,11 +452,11 @@ void FlipperConnectionManagerImpl::requestSignedCertificate() {
   auto gettingCert = flipperState_->start("Getting cert from desktop");
 
   certificateExchangeCompleted_ = false;
-  flipperEventBase_->add([this, message, gettingCert]() {
+  flipperScheduler_->schedule([this, message, gettingCert]() {
     client_->sendExpectResponse(
         folly::toJson(message),
         [this, gettingCert](const std::string& response, bool isError) {
-          flipperEventBase_->add([this, gettingCert, response, isError]() {
+          flipperScheduler_->schedule([this, gettingCert, response, isError]() {
             this->processSignedCertificateResponse(
                 gettingCert, response, isError);
           });
@@ -471,7 +466,7 @@ void FlipperConnectionManagerImpl::requestSignedCertificate() {
 }
 
 bool FlipperConnectionManagerImpl::isRunningInOwnThread() {
-  return flipperEventBase_->isInEventBaseThread();
+  return flipperScheduler_->isRunningInOwnThread();
 }
 
 } // namespace flipper

xplat/Flipper/FlipperConnectionManagerImpl.h

@@ -7,11 +7,10 @@
 
 #pragma once
 
-#include <folly/Executor.h>
-#include <folly/io/async/EventBase.h>
 #include <mutex>
 #include "FlipperConnectionManager.h"
 #include "FlipperInitConfig.h"
+#include "FlipperScheduler.h"
 #include "FlipperSocket.h"
 #include "FlipperState.h"
 
@@ -64,8 +63,8 @@ class FlipperConnectionManagerImpl : public FlipperConnectionManager {
   int altInsecurePort;
   int altSecurePort;
 
-  folly::EventBase* flipperEventBase_;
-  folly::EventBase* connectionEventBase_;
+  Scheduler* flipperScheduler_;
+  Scheduler* connectionScheduler_;
 
   std::unique_ptr<FlipperSocket> client_;
 

xplat/Flipper/FlipperInitConfig.h

@@ -7,8 +7,8 @@
 
 #pragma once
 
-#include <folly/io/async/EventBase.h>
 #include <map>
+#include "FlipperScheduler.h"
 
 namespace facebook {
 namespace flipper {
@@ -30,14 +30,14 @@ struct FlipperInitConfig {
   DeviceData deviceData;
 
   /**
-  EventBase on which client callbacks should be called.
+  Scheduler on which client callbacks should be called.
   */
-  folly::EventBase* callbackWorker;
+  Scheduler* callbackWorker;
 
   /**
-  EventBase to be used to maintain the network connection.
+  Scheduler to be used to maintain the network connection.
   */
-  folly::EventBase* connectionWorker;
+  Scheduler* connectionWorker;
 
   int insecurePort = 9089;
   int securePort = 9088;

xplat/Flipper/FlipperSocketProvider.cpp

@@ -21,19 +21,19 @@ std::unique_ptr<FlipperSocketProvider> FlipperSocketProvider::shelvedProvider_ =
 std::unique_ptr<FlipperSocket> FlipperSocketProvider::socketCreate(
     FlipperConnectionEndpoint endpoint,
     std::unique_ptr<FlipperSocketBasePayload> payload,
-    folly::EventBase* eventBase) {
-  return provider_->create(std::move(endpoint), std::move(payload), eventBase);
+    Scheduler* scheduler) {
+  return provider_->create(std::move(endpoint), std::move(payload), scheduler);
 }
 
 std::unique_ptr<FlipperSocket> FlipperSocketProvider::socketCreate(
     FlipperConnectionEndpoint endpoint,
     std::unique_ptr<FlipperSocketBasePayload> payload,
-    folly::EventBase* eventBase,
+    Scheduler* scheduler,
     ConnectionContextStore* connectionContextStore) {
   return provider_->create(
       std::move(endpoint),
       std::move(payload),
-      eventBase,
+      scheduler,
       connectionContextStore);
 }
 

xplat/Flipper/FlipperSocketProvider.h

@@ -7,8 +7,8 @@
 
 #pragma once
 
-#include <folly/io/async/EventBase.h>
 #include <memory>
+#include "FlipperScheduler.h"
 
 namespace facebook {
 namespace flipper {
@@ -32,35 +32,37 @@ class FlipperSocketProvider {
    @param endpoint Endpoint to connect to.
    @param payload Any configuration payload to establish a connection with
    the specified endpoint.
-   @param eventBase A folly event base used to execute connection operations.
+   @param scheduler An scheduler used to schedule and execute connection
+   operations.
    */
   virtual std::unique_ptr<FlipperSocket> create(
       FlipperConnectionEndpoint endpoint,
       std::unique_ptr<FlipperSocketBasePayload> payload,
-      folly::EventBase* eventBase) = 0;
+      Scheduler* scheduler) = 0;
   /**
    Create an instance of FlipperSocket.
    @param endpoint Endpoint to connect to.
    @param payload Any configuration payload to establish a connection with
    the specified endpoint.
-   @param eventBase A folly event base used to execute connection operations.
+   @param scheduler An scheduler used to schedule and execute connection
+   operations.
    @param connectionContextStore A connection context store used for obtaining
    the certificate used for secure connections.
    */
   virtual std::unique_ptr<FlipperSocket> create(
       FlipperConnectionEndpoint endpoint,
       std::unique_ptr<FlipperSocketBasePayload> payload,
-      folly::EventBase* eventBase,
+      Scheduler* scheduler,
       ConnectionContextStore* connectionContextStore) = 0;
 
   static std::unique_ptr<FlipperSocket> socketCreate(
       FlipperConnectionEndpoint endpoint,
       std::unique_ptr<FlipperSocketBasePayload> payload,
-      folly::EventBase* eventBase);
+      Scheduler* scheduler);
   static std::unique_ptr<FlipperSocket> socketCreate(
       FlipperConnectionEndpoint endpoint,
       std::unique_ptr<FlipperSocketBasePayload> payload,
-      folly::EventBase* eventBase,
+      Scheduler* scheduler,
       ConnectionContextStore* connectionContextStore);
 
   static void setDefaultProvider(