Mercurial > hg > sv-dependency-builds
diff osx/include/capnp/ez-rpc.h @ 49:3ab5a40c4e3b
Add Capnp and KJ builds for OSX
author | Chris Cannam <cannam@all-day-breakfast.com> |
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date | Tue, 25 Oct 2016 14:48:23 +0100 |
parents | |
children | 0994c39f1e94 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/osx/include/capnp/ez-rpc.h Tue Oct 25 14:48:23 2016 +0100 @@ -0,0 +1,254 @@ +// Copyright (c) 2013-2014 Sandstorm Development Group, Inc. and contributors +// Licensed under the MIT License: +// +// Permission is hereby granted, free of charge, to any person obtaining a copy +// of this software and associated documentation files (the "Software"), to deal +// in the Software without restriction, including without limitation the rights +// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +// copies of the Software, and to permit persons to whom the Software is +// furnished to do so, subject to the following conditions: +// +// The above copyright notice and this permission notice shall be included in +// all copies or substantial portions of the Software. +// +// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN +// THE SOFTWARE. + +#ifndef CAPNP_EZ_RPC_H_ +#define CAPNP_EZ_RPC_H_ + +#if defined(__GNUC__) && !defined(CAPNP_HEADER_WARNINGS) +#pragma GCC system_header +#endif + +#include "rpc.h" +#include "message.h" + +struct sockaddr; + +namespace kj { class AsyncIoProvider; class LowLevelAsyncIoProvider; } + +namespace capnp { + +class EzRpcContext; + +class EzRpcClient { + // Super-simple interface for setting up a Cap'n Proto RPC client. Example: + // + // # Cap'n Proto schema + // interface Adder { + // add @0 (left :Int32, right :Int32) -> (value :Int32); + // } + // + // // C++ client + // int main() { + // capnp::EzRpcClient client("localhost:3456"); + // Adder::Client adder = client.getMain<Adder>(); + // auto request = adder.addRequest(); + // request.setLeft(12); + // request.setRight(34); + // auto response = request.send().wait(client.getWaitScope()); + // assert(response.getValue() == 46); + // return 0; + // } + // + // // C++ server + // class AdderImpl final: public Adder::Server { + // public: + // kj::Promise<void> add(AddContext context) override { + // auto params = context.getParams(); + // context.getResults().setValue(params.getLeft() + params.getRight()); + // return kj::READY_NOW; + // } + // }; + // + // int main() { + // capnp::EzRpcServer server(kj::heap<AdderImpl>(), "*:3456"); + // kj::NEVER_DONE.wait(server.getWaitScope()); + // } + // + // This interface is easy, but it hides a lot of useful features available from the lower-level + // classes: + // - The server can only export a small set of public, singleton capabilities under well-known + // string names. This is fine for transient services where no state needs to be kept between + // connections, but hides the power of Cap'n Proto when it comes to long-lived resources. + // - EzRpcClient/EzRpcServer automatically set up a `kj::EventLoop` and make it current for the + // thread. Only one `kj::EventLoop` can exist per thread, so you cannot use these interfaces + // if you wish to set up your own event loop. (However, you can safely create multiple + // EzRpcClient / EzRpcServer objects in a single thread; they will make sure to make no more + // than one EventLoop.) + // - These classes only support simple two-party connections, not multilateral VatNetworks. + // - These classes only support communication over a raw, unencrypted socket. If you want to + // build on an abstract stream (perhaps one which supports encryption), you must use the + // lower-level interfaces. + // + // Some of these restrictions will probably be lifted in future versions, but some things will + // always require using the low-level interfaces directly. If you are interested in working + // at a lower level, start by looking at these interfaces: + // - `kj::setupAsyncIo()` in `kj/async-io.h`. + // - `RpcSystem` in `capnp/rpc.h`. + // - `TwoPartyVatNetwork` in `capnp/rpc-twoparty.h`. + +public: + explicit EzRpcClient(kj::StringPtr serverAddress, uint defaultPort = 0, + ReaderOptions readerOpts = ReaderOptions()); + // Construct a new EzRpcClient and connect to the given address. The connection is formed in + // the background -- if it fails, calls to capabilities returned by importCap() will fail with an + // appropriate exception. + // + // `defaultPort` is the IP port number to use if `serverAddress` does not include it explicitly. + // If unspecified, the port is required in `serverAddress`. + // + // The address is parsed by `kj::Network` in `kj/async-io.h`. See that interface for more info + // on the address format, but basically it's what you'd expect. + // + // `readerOpts` is the ReaderOptions structure used to read each incoming message on the + // connection. Setting this may be necessary if you need to receive very large individual + // messages or messages. However, it is recommended that you instead think about how to change + // your protocol to send large data blobs in multiple small chunks -- this is much better for + // both security and performance. See `ReaderOptions` in `message.h` for more details. + + EzRpcClient(const struct sockaddr* serverAddress, uint addrSize, + ReaderOptions readerOpts = ReaderOptions()); + // Like the above constructor, but connects to an already-resolved socket address. Any address + // format supported by `kj::Network` in `kj/async-io.h` is accepted. + + explicit EzRpcClient(int socketFd, ReaderOptions readerOpts = ReaderOptions()); + // Create a client on top of an already-connected socket. + // `readerOpts` acts as in the first constructor. + + ~EzRpcClient() noexcept(false); + + template <typename Type> + typename Type::Client getMain(); + Capability::Client getMain(); + // Get the server's main (aka "bootstrap") interface. + + template <typename Type> + typename Type::Client importCap(kj::StringPtr name) + KJ_DEPRECATED("Change your server to export a main interface, then use getMain() instead."); + Capability::Client importCap(kj::StringPtr name) + KJ_DEPRECATED("Change your server to export a main interface, then use getMain() instead."); + // ** DEPRECATED ** + // + // Ask the sever for the capability with the given name. You may specify a type to automatically + // down-cast to that type. It is up to you to specify the correct expected type. + // + // Named interfaces are deprecated. The new preferred usage pattern is for the server to export + // a "main" interface which itself has methods for getting any other interfaces. + + kj::WaitScope& getWaitScope(); + // Get the `WaitScope` for the client's `EventLoop`, which allows you to synchronously wait on + // promises. + + kj::AsyncIoProvider& getIoProvider(); + // Get the underlying AsyncIoProvider set up by the RPC system. This is useful if you want + // to do some non-RPC I/O in asynchronous fashion. + + kj::LowLevelAsyncIoProvider& getLowLevelIoProvider(); + // Get the underlying LowLevelAsyncIoProvider set up by the RPC system. This is useful if you + // want to do some non-RPC I/O in asynchronous fashion. + +private: + struct Impl; + kj::Own<Impl> impl; +}; + +class EzRpcServer { + // The server counterpart to `EzRpcClient`. See `EzRpcClient` for an example. + +public: + explicit EzRpcServer(Capability::Client mainInterface, kj::StringPtr bindAddress, + uint defaultPort = 0, ReaderOptions readerOpts = ReaderOptions()); + // Construct a new `EzRpcServer` that binds to the given address. An address of "*" means to + // bind to all local addresses. + // + // `defaultPort` is the IP port number to use if `serverAddress` does not include it explicitly. + // If unspecified, a port is chosen automatically, and you must call getPort() to find out what + // it is. + // + // The address is parsed by `kj::Network` in `kj/async-io.h`. See that interface for more info + // on the address format, but basically it's what you'd expect. + // + // The server might not begin listening immediately, especially if `bindAddress` needs to be + // resolved. If you need to wait until the server is definitely up, wait on the promise returned + // by `getPort()`. + // + // `readerOpts` is the ReaderOptions structure used to read each incoming message on the + // connection. Setting this may be necessary if you need to receive very large individual + // messages or messages. However, it is recommended that you instead think about how to change + // your protocol to send large data blobs in multiple small chunks -- this is much better for + // both security and performance. See `ReaderOptions` in `message.h` for more details. + + EzRpcServer(Capability::Client mainInterface, struct sockaddr* bindAddress, uint addrSize, + ReaderOptions readerOpts = ReaderOptions()); + // Like the above constructor, but binds to an already-resolved socket address. Any address + // format supported by `kj::Network` in `kj/async-io.h` is accepted. + + EzRpcServer(Capability::Client mainInterface, int socketFd, uint port, + ReaderOptions readerOpts = ReaderOptions()); + // Create a server on top of an already-listening socket (i.e. one on which accept() may be + // called). `port` is returned by `getPort()` -- it serves no other purpose. + // `readerOpts` acts as in the other two above constructors. + + explicit EzRpcServer(kj::StringPtr bindAddress, uint defaultPort = 0, + ReaderOptions readerOpts = ReaderOptions()) + KJ_DEPRECATED("Please specify a main interface for your server."); + EzRpcServer(struct sockaddr* bindAddress, uint addrSize, + ReaderOptions readerOpts = ReaderOptions()) + KJ_DEPRECATED("Please specify a main interface for your server."); + EzRpcServer(int socketFd, uint port, ReaderOptions readerOpts = ReaderOptions()) + KJ_DEPRECATED("Please specify a main interface for your server."); + + ~EzRpcServer() noexcept(false); + + void exportCap(kj::StringPtr name, Capability::Client cap); + // Export a capability publicly under the given name, so that clients can import it. + // + // Keep in mind that you can implicitly convert `kj::Own<MyType::Server>&&` to + // `Capability::Client`, so it's typical to pass something like + // `kj::heap<MyImplementation>(<constructor params>)` as the second parameter. + + kj::Promise<uint> getPort(); + // Get the IP port number on which this server is listening. This promise won't resolve until + // the server is actually listening. If the address was not an IP address (e.g. it was a Unix + // domain socket) then getPort() resolves to zero. + + kj::WaitScope& getWaitScope(); + // Get the `WaitScope` for the client's `EventLoop`, which allows you to synchronously wait on + // promises. + + kj::AsyncIoProvider& getIoProvider(); + // Get the underlying AsyncIoProvider set up by the RPC system. This is useful if you want + // to do some non-RPC I/O in asynchronous fashion. + + kj::LowLevelAsyncIoProvider& getLowLevelIoProvider(); + // Get the underlying LowLevelAsyncIoProvider set up by the RPC system. This is useful if you + // want to do some non-RPC I/O in asynchronous fashion. + +private: + struct Impl; + kj::Own<Impl> impl; +}; + +// ======================================================================================= +// inline implementation details + +template <typename Type> +inline typename Type::Client EzRpcClient::getMain() { + return getMain().castAs<Type>(); +} + +template <typename Type> +inline typename Type::Client EzRpcClient::importCap(kj::StringPtr name) { + return importCap(name).castAs<Type>(); +} + +} // namespace capnp + +#endif // CAPNP_EZ_RPC_H_