sapling/eden/fs/service/EdenServiceHandler.h

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/*
* Copyright (c) 2016-present, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*
*/
#pragma once
#include "common/fb303/cpp/FacebookBase2.h"
Reimplement dirstate used by Eden's Hg extension as a subclass of Hg's dirstate. Summary: This is a major change to Eden's Hg extension. Our initial attempt to implement `edendirstate` was to create a "clean room" implementation that did not share code with `mercurial/dirstate.py`. This was helpful in uncovering the subset of the dirstate API that matters for Eden. It also provided a better safeguard against upstream changes to `dirstate.py` in Mercurial itself. In this implementation, the state transition management was mostly done on the server in `Dirstate.cpp`. We also made a modest attempt to make `Dirstate.cpp` "SCM-agnostic" such that the same APIs could be used for Git at some point. However, as we have tried to support more of the sophisticated functionality in Mercurial, particularly `hg histedit`, achieving parity between the clean room implementation and Mercurial's internals has become more challenging. Ultimately, the clean room implementation is likely the right way to go for Eden, but for now, we need to prioritize having feature parity with vanilla Hg when using Eden. Once we have a more complete set of integration tests in place, we can reimplement Eden's dirstate more aggressively to optimize things. Fortunately, the [[ https://bitbucket.org/facebook/hg-experimental/src/default/sqldirstate/ | sqldirstate ]] extension has already demonstrated that it is possible to provide a faithful dirstate implementation that subclasses the original `dirstate` while using a different storage mechanism. As such, I used `sqldirstate` as a model when implementing the new `eden_dirstate` (distinguishing it from our v1 implementation, `edendirstate`). In particular, `sqldirstate` uses SQL tables as storage for the following private fields of `dirstate`: `_map`, `_dirs`, `_copymap`, `_filefoldmap`, `_dirfoldmap`. Because `_filefoldmap` and `_dirfoldmap` exist to deal with case-insensitivity issues, we do not support them in `eden_dirstate` and add code to ensure the codepaths that would access them in `dirstate` never get exercised. Similarly, we also implemented `eden_dirstate` so that it never accesses `_dirs`. (`_dirs` is a multiset of all directories in the dirstate, which is an O(repo) data structure, so we do not want to maintain it in Eden. It appears to be primarily used for checking whether a path to a file already exists in the dirstate as a directory. We can protect against that in more efficient ways.) That leaves only `_map` and `_copymap` to worry about. `_copymap` contains the set of files that have been marked "copied" in the current dirstate, so it is fairly small and can be stored on disk or in memory with little concern. `_map` is a bit trickier because it is expected to have an entry for every file in the dirstate. In `sqldirstate`, it is stored across two tables: `files` and `nonnormalfiles`. For Eden, we already represent the data analogous to the `files` table in RocksDB/the overlay, so we do not need to create a new equivalent to the `files` table. We do, however, need an equivalent to the `nonnormalfiles` table, which we store in as Thrift-serialized data in an ordinary file along with the `_copymap` data. In our Hg extension, our implementation of `_map` is `eden_dirstate_map`, which is defined in a Python file of the same name. Our implementation of `_copymap` is `dummy_copymap`, which is defined in `eden_dirstate.py`. Both of these collections are simple pass-through data structures that translate their method calls to Thrift server calls. I expect we will want to optimize this in the future via some client-side caching, as well as creating batch APIs for talking to the server via Thrift. One advantage of this new implementation is that it enables us to delete `eden/hg/eden/overrides.py`, which overrode the entry points for `hg add` and `hg remove`. Between the recent implementation of `dirstate.walk()` for Eden and this switch to the real dirstate, we can now use the default implementation of `hg add` and `hg remove` (although we have to play some tricks, like in the implementation of `eden_dirstate.status()` in order to make `hg remove` work). In the course of doing this revision, I discovered that I had to make a minor fix to `EdenMatchInfo.make_glob_list()` because `hg add foo` was being treated as `hg add foo/**/*` even when `foo` was just a file (as opposed to a directory), in which case the glob was not matching `foo`! I also had to do some work in `eden_dirstate.status()` in which the `match` argument was previously largely ignored. It turns out that `dirstate.py` uses `status()` for a number of things with the `match` specified as a filter, so the output of `status()` must be filtered by `match` accordingly. Ultimately, this seems like work that would be better done on the server, but for simplicity, we're just going to do it in Python, for now. For the reasons explained above, this revision deletes a lot of code `Dirstate.cpp`. As such, `DirstateTest.cpp` does not seem worth refactoring, though the scenarios it was testing should probably be converted to integration tests. At a high level, the role of `DirstatePersistence` has not changed, but the exact data it writes is much different. Its corresponding unit test is also disabled, for now. Note that this revision does not change the name of the file where "dirstate data" is written (this is defined as `kDirstateFile` in `ClientConfig.cpp`), so we should blow away any existing instances of this file once this change lands. (It is still early enough in the project that it does not seem worth the overhead of a proper migration.) The true test of the success of this new approach is the ease with which we can write more integration tests for things like `hg histedit` and `hg graft`. Ideally, these should require very few changes to `eden_dirstate.py`. Reviewed By: simpkins Differential Revision: D5071778 fbshipit-source-id: e8fec4d393035d80f36516ac050cad025dc3ba31
2017-05-26 21:51:30 +03:00
#include "eden/fs/inodes/gen-cpp2/hgdirstate_types.h"
#include "eden/fs/service/gen-cpp2/StreamingEdenService.h"
#include "eden/fs/utils/PathFuncs.h"
namespace folly {
template <typename T>
class Future;
}
namespace facebook {
namespace eden {
class Hash;
class EdenServer;
class TreeInode;
/*
* Handler for the EdenService thrift interface
*/
class EdenServiceHandler : virtual public StreamingEdenServiceSvIf,
public facebook::fb303::FacebookBase2 {
public:
explicit EdenServiceHandler(EdenServer* server);
facebook::fb303::cpp2::fb_status getStatus() override;
void mount(std::unique_ptr<MountInfo> info) override;
void unmount(std::unique_ptr<std::string> mountPoint) override;
void listMounts(std::vector<MountInfo>& results) override;
void getParentCommits(
WorkingDirectoryParents& result,
std::unique_ptr<std::string> mountPoint) override;
void checkOutRevision(
std::vector<CheckoutConflict>& results,
std::unique_ptr<std::string> mountPoint,
std::unique_ptr<std::string> hash,
bool force) override;
void resetParentCommits(
std::unique_ptr<std::string> mountPoint,
std::unique_ptr<WorkingDirectoryParents> parents) override;
void getBindMounts(
std::vector<std::string>& out,
std::unique_ptr<std::string> mountPoint) override;
void getSHA1(
std::vector<SHA1Result>& out,
std::unique_ptr<std::string> mountPoint,
std::unique_ptr<std::vector<std::string>> paths) override;
void getCurrentJournalPosition(
JournalPosition& out,
std::unique_ptr<std::string> mountPoint) override;
void getFilesChangedSince(
FileDelta& out,
std::unique_ptr<std::string> mountPoint,
std::unique_ptr<JournalPosition> fromPosition) override;
void getFileInformation(
std::vector<FileInformationOrError>& out,
std::unique_ptr<std::string> mountPoint,
std::unique_ptr<std::vector<std::string>> paths) override;
implement glob thrift method Summary: This is to facilitate the watchman integration and draws on the watchman glob implementation; the approach is to split the glob strings into path components and evaluate the components step by step as the tree is walked. Components that do not include any glob special characters can be handled as a direct lookup from the directory contents (O(1) rather than O(num-entries)). The glob method returns a set of filenames that match a list of of glob patterns. Recursive globs are supported. It is worth noting that a glob like "**/*" will return a list of every entry in the filesystem. This is potentially expensive and should be avoided. simpkins is in favor of disallowing this as a forcing function to encourage tool-makers to adopt patterns that don't rely on a complete listing of the filesystem. For now I'd like to get this in without such a restriction; it's also worth noting that running `find .` in the root of the mount point has a similar effect and we can't prevent that from happening, so the effect of the overly broad glob is something that we need to be able to withstand in any case. Unrestricted recursive globs will make it easier to connect certain watchman queries in the interim, until we have a more expressive thrift API for walking and filtering the list of files. Note: I've removed the wildmatch flags that I'd put in the API when I stubbed it out originally. Since this is built on top of our GlobMatcher code and that doesn't have those flags, I thought it would be simplest to just remove them. If we find that we need them, we can figure out how to add them later. Also Note: the evaluation of the glob is parallel-ready but currently limited to 1 at a time by constraining the folly::window call to 1. We could make this larger but would need a more intelligent constraint. For example, a recursive glob could initiate N concurrent futures per level where N is the number of sub-dirs at a given level. Using a custom Executor for these futures may be a better option to set an upper bound on the number of concurrent jobs allowed for a given glob call. Depends on D4361197 Reviewed By: simpkins Differential Revision: D4371934 fbshipit-source-id: 444735600bc16d2c2185f2277ddc5b51f672600a
2017-01-26 23:45:50 +03:00
void glob(
std::vector<std::string>& out,
std::unique_ptr<std::string> mountPoint,
std::unique_ptr<std::vector<std::string>> globs) override;
void async_tm_subscribe(
std::unique_ptr<apache::thrift::StreamingHandlerCallback<
std::unique_ptr<JournalPosition>>> callback,
std::unique_ptr<std::string> mountPoint) override;
void scmGetStatus(
ThriftHgStatus& out,
std::unique_ptr<std::string> mountPoint,
bool listIgnored) override;
Reimplement dirstate used by Eden's Hg extension as a subclass of Hg's dirstate. Summary: This is a major change to Eden's Hg extension. Our initial attempt to implement `edendirstate` was to create a "clean room" implementation that did not share code with `mercurial/dirstate.py`. This was helpful in uncovering the subset of the dirstate API that matters for Eden. It also provided a better safeguard against upstream changes to `dirstate.py` in Mercurial itself. In this implementation, the state transition management was mostly done on the server in `Dirstate.cpp`. We also made a modest attempt to make `Dirstate.cpp` "SCM-agnostic" such that the same APIs could be used for Git at some point. However, as we have tried to support more of the sophisticated functionality in Mercurial, particularly `hg histedit`, achieving parity between the clean room implementation and Mercurial's internals has become more challenging. Ultimately, the clean room implementation is likely the right way to go for Eden, but for now, we need to prioritize having feature parity with vanilla Hg when using Eden. Once we have a more complete set of integration tests in place, we can reimplement Eden's dirstate more aggressively to optimize things. Fortunately, the [[ https://bitbucket.org/facebook/hg-experimental/src/default/sqldirstate/ | sqldirstate ]] extension has already demonstrated that it is possible to provide a faithful dirstate implementation that subclasses the original `dirstate` while using a different storage mechanism. As such, I used `sqldirstate` as a model when implementing the new `eden_dirstate` (distinguishing it from our v1 implementation, `edendirstate`). In particular, `sqldirstate` uses SQL tables as storage for the following private fields of `dirstate`: `_map`, `_dirs`, `_copymap`, `_filefoldmap`, `_dirfoldmap`. Because `_filefoldmap` and `_dirfoldmap` exist to deal with case-insensitivity issues, we do not support them in `eden_dirstate` and add code to ensure the codepaths that would access them in `dirstate` never get exercised. Similarly, we also implemented `eden_dirstate` so that it never accesses `_dirs`. (`_dirs` is a multiset of all directories in the dirstate, which is an O(repo) data structure, so we do not want to maintain it in Eden. It appears to be primarily used for checking whether a path to a file already exists in the dirstate as a directory. We can protect against that in more efficient ways.) That leaves only `_map` and `_copymap` to worry about. `_copymap` contains the set of files that have been marked "copied" in the current dirstate, so it is fairly small and can be stored on disk or in memory with little concern. `_map` is a bit trickier because it is expected to have an entry for every file in the dirstate. In `sqldirstate`, it is stored across two tables: `files` and `nonnormalfiles`. For Eden, we already represent the data analogous to the `files` table in RocksDB/the overlay, so we do not need to create a new equivalent to the `files` table. We do, however, need an equivalent to the `nonnormalfiles` table, which we store in as Thrift-serialized data in an ordinary file along with the `_copymap` data. In our Hg extension, our implementation of `_map` is `eden_dirstate_map`, which is defined in a Python file of the same name. Our implementation of `_copymap` is `dummy_copymap`, which is defined in `eden_dirstate.py`. Both of these collections are simple pass-through data structures that translate their method calls to Thrift server calls. I expect we will want to optimize this in the future via some client-side caching, as well as creating batch APIs for talking to the server via Thrift. One advantage of this new implementation is that it enables us to delete `eden/hg/eden/overrides.py`, which overrode the entry points for `hg add` and `hg remove`. Between the recent implementation of `dirstate.walk()` for Eden and this switch to the real dirstate, we can now use the default implementation of `hg add` and `hg remove` (although we have to play some tricks, like in the implementation of `eden_dirstate.status()` in order to make `hg remove` work). In the course of doing this revision, I discovered that I had to make a minor fix to `EdenMatchInfo.make_glob_list()` because `hg add foo` was being treated as `hg add foo/**/*` even when `foo` was just a file (as opposed to a directory), in which case the glob was not matching `foo`! I also had to do some work in `eden_dirstate.status()` in which the `match` argument was previously largely ignored. It turns out that `dirstate.py` uses `status()` for a number of things with the `match` specified as a filter, so the output of `status()` must be filtered by `match` accordingly. Ultimately, this seems like work that would be better done on the server, but for simplicity, we're just going to do it in Python, for now. For the reasons explained above, this revision deletes a lot of code `Dirstate.cpp`. As such, `DirstateTest.cpp` does not seem worth refactoring, though the scenarios it was testing should probably be converted to integration tests. At a high level, the role of `DirstatePersistence` has not changed, but the exact data it writes is much different. Its corresponding unit test is also disabled, for now. Note that this revision does not change the name of the file where "dirstate data" is written (this is defined as `kDirstateFile` in `ClientConfig.cpp`), so we should blow away any existing instances of this file once this change lands. (It is still early enough in the project that it does not seem worth the overhead of a proper migration.) The true test of the success of this new approach is the ease with which we can write more integration tests for things like `hg histedit` and `hg graft`. Ideally, these should require very few changes to `eden_dirstate.py`. Reviewed By: simpkins Differential Revision: D5071778 fbshipit-source-id: e8fec4d393035d80f36516ac050cad025dc3ba31
2017-05-26 21:51:30 +03:00
void hgGetDirstateTuple(
hgdirstate::DirstateTuple& out,
std::unique_ptr<std::string> mountPoint,
Reimplement dirstate used by Eden's Hg extension as a subclass of Hg's dirstate. Summary: This is a major change to Eden's Hg extension. Our initial attempt to implement `edendirstate` was to create a "clean room" implementation that did not share code with `mercurial/dirstate.py`. This was helpful in uncovering the subset of the dirstate API that matters for Eden. It also provided a better safeguard against upstream changes to `dirstate.py` in Mercurial itself. In this implementation, the state transition management was mostly done on the server in `Dirstate.cpp`. We also made a modest attempt to make `Dirstate.cpp` "SCM-agnostic" such that the same APIs could be used for Git at some point. However, as we have tried to support more of the sophisticated functionality in Mercurial, particularly `hg histedit`, achieving parity between the clean room implementation and Mercurial's internals has become more challenging. Ultimately, the clean room implementation is likely the right way to go for Eden, but for now, we need to prioritize having feature parity with vanilla Hg when using Eden. Once we have a more complete set of integration tests in place, we can reimplement Eden's dirstate more aggressively to optimize things. Fortunately, the [[ https://bitbucket.org/facebook/hg-experimental/src/default/sqldirstate/ | sqldirstate ]] extension has already demonstrated that it is possible to provide a faithful dirstate implementation that subclasses the original `dirstate` while using a different storage mechanism. As such, I used `sqldirstate` as a model when implementing the new `eden_dirstate` (distinguishing it from our v1 implementation, `edendirstate`). In particular, `sqldirstate` uses SQL tables as storage for the following private fields of `dirstate`: `_map`, `_dirs`, `_copymap`, `_filefoldmap`, `_dirfoldmap`. Because `_filefoldmap` and `_dirfoldmap` exist to deal with case-insensitivity issues, we do not support them in `eden_dirstate` and add code to ensure the codepaths that would access them in `dirstate` never get exercised. Similarly, we also implemented `eden_dirstate` so that it never accesses `_dirs`. (`_dirs` is a multiset of all directories in the dirstate, which is an O(repo) data structure, so we do not want to maintain it in Eden. It appears to be primarily used for checking whether a path to a file already exists in the dirstate as a directory. We can protect against that in more efficient ways.) That leaves only `_map` and `_copymap` to worry about. `_copymap` contains the set of files that have been marked "copied" in the current dirstate, so it is fairly small and can be stored on disk or in memory with little concern. `_map` is a bit trickier because it is expected to have an entry for every file in the dirstate. In `sqldirstate`, it is stored across two tables: `files` and `nonnormalfiles`. For Eden, we already represent the data analogous to the `files` table in RocksDB/the overlay, so we do not need to create a new equivalent to the `files` table. We do, however, need an equivalent to the `nonnormalfiles` table, which we store in as Thrift-serialized data in an ordinary file along with the `_copymap` data. In our Hg extension, our implementation of `_map` is `eden_dirstate_map`, which is defined in a Python file of the same name. Our implementation of `_copymap` is `dummy_copymap`, which is defined in `eden_dirstate.py`. Both of these collections are simple pass-through data structures that translate their method calls to Thrift server calls. I expect we will want to optimize this in the future via some client-side caching, as well as creating batch APIs for talking to the server via Thrift. One advantage of this new implementation is that it enables us to delete `eden/hg/eden/overrides.py`, which overrode the entry points for `hg add` and `hg remove`. Between the recent implementation of `dirstate.walk()` for Eden and this switch to the real dirstate, we can now use the default implementation of `hg add` and `hg remove` (although we have to play some tricks, like in the implementation of `eden_dirstate.status()` in order to make `hg remove` work). In the course of doing this revision, I discovered that I had to make a minor fix to `EdenMatchInfo.make_glob_list()` because `hg add foo` was being treated as `hg add foo/**/*` even when `foo` was just a file (as opposed to a directory), in which case the glob was not matching `foo`! I also had to do some work in `eden_dirstate.status()` in which the `match` argument was previously largely ignored. It turns out that `dirstate.py` uses `status()` for a number of things with the `match` specified as a filter, so the output of `status()` must be filtered by `match` accordingly. Ultimately, this seems like work that would be better done on the server, but for simplicity, we're just going to do it in Python, for now. For the reasons explained above, this revision deletes a lot of code `Dirstate.cpp`. As such, `DirstateTest.cpp` does not seem worth refactoring, though the scenarios it was testing should probably be converted to integration tests. At a high level, the role of `DirstatePersistence` has not changed, but the exact data it writes is much different. Its corresponding unit test is also disabled, for now. Note that this revision does not change the name of the file where "dirstate data" is written (this is defined as `kDirstateFile` in `ClientConfig.cpp`), so we should blow away any existing instances of this file once this change lands. (It is still early enough in the project that it does not seem worth the overhead of a proper migration.) The true test of the success of this new approach is the ease with which we can write more integration tests for things like `hg histedit` and `hg graft`. Ideally, these should require very few changes to `eden_dirstate.py`. Reviewed By: simpkins Differential Revision: D5071778 fbshipit-source-id: e8fec4d393035d80f36516ac050cad025dc3ba31
2017-05-26 21:51:30 +03:00
std::unique_ptr<std::string> relativePath) override;
Reimplement dirstate used by Eden's Hg extension as a subclass of Hg's dirstate. Summary: This is a major change to Eden's Hg extension. Our initial attempt to implement `edendirstate` was to create a "clean room" implementation that did not share code with `mercurial/dirstate.py`. This was helpful in uncovering the subset of the dirstate API that matters for Eden. It also provided a better safeguard against upstream changes to `dirstate.py` in Mercurial itself. In this implementation, the state transition management was mostly done on the server in `Dirstate.cpp`. We also made a modest attempt to make `Dirstate.cpp` "SCM-agnostic" such that the same APIs could be used for Git at some point. However, as we have tried to support more of the sophisticated functionality in Mercurial, particularly `hg histedit`, achieving parity between the clean room implementation and Mercurial's internals has become more challenging. Ultimately, the clean room implementation is likely the right way to go for Eden, but for now, we need to prioritize having feature parity with vanilla Hg when using Eden. Once we have a more complete set of integration tests in place, we can reimplement Eden's dirstate more aggressively to optimize things. Fortunately, the [[ https://bitbucket.org/facebook/hg-experimental/src/default/sqldirstate/ | sqldirstate ]] extension has already demonstrated that it is possible to provide a faithful dirstate implementation that subclasses the original `dirstate` while using a different storage mechanism. As such, I used `sqldirstate` as a model when implementing the new `eden_dirstate` (distinguishing it from our v1 implementation, `edendirstate`). In particular, `sqldirstate` uses SQL tables as storage for the following private fields of `dirstate`: `_map`, `_dirs`, `_copymap`, `_filefoldmap`, `_dirfoldmap`. Because `_filefoldmap` and `_dirfoldmap` exist to deal with case-insensitivity issues, we do not support them in `eden_dirstate` and add code to ensure the codepaths that would access them in `dirstate` never get exercised. Similarly, we also implemented `eden_dirstate` so that it never accesses `_dirs`. (`_dirs` is a multiset of all directories in the dirstate, which is an O(repo) data structure, so we do not want to maintain it in Eden. It appears to be primarily used for checking whether a path to a file already exists in the dirstate as a directory. We can protect against that in more efficient ways.) That leaves only `_map` and `_copymap` to worry about. `_copymap` contains the set of files that have been marked "copied" in the current dirstate, so it is fairly small and can be stored on disk or in memory with little concern. `_map` is a bit trickier because it is expected to have an entry for every file in the dirstate. In `sqldirstate`, it is stored across two tables: `files` and `nonnormalfiles`. For Eden, we already represent the data analogous to the `files` table in RocksDB/the overlay, so we do not need to create a new equivalent to the `files` table. We do, however, need an equivalent to the `nonnormalfiles` table, which we store in as Thrift-serialized data in an ordinary file along with the `_copymap` data. In our Hg extension, our implementation of `_map` is `eden_dirstate_map`, which is defined in a Python file of the same name. Our implementation of `_copymap` is `dummy_copymap`, which is defined in `eden_dirstate.py`. Both of these collections are simple pass-through data structures that translate their method calls to Thrift server calls. I expect we will want to optimize this in the future via some client-side caching, as well as creating batch APIs for talking to the server via Thrift. One advantage of this new implementation is that it enables us to delete `eden/hg/eden/overrides.py`, which overrode the entry points for `hg add` and `hg remove`. Between the recent implementation of `dirstate.walk()` for Eden and this switch to the real dirstate, we can now use the default implementation of `hg add` and `hg remove` (although we have to play some tricks, like in the implementation of `eden_dirstate.status()` in order to make `hg remove` work). In the course of doing this revision, I discovered that I had to make a minor fix to `EdenMatchInfo.make_glob_list()` because `hg add foo` was being treated as `hg add foo/**/*` even when `foo` was just a file (as opposed to a directory), in which case the glob was not matching `foo`! I also had to do some work in `eden_dirstate.status()` in which the `match` argument was previously largely ignored. It turns out that `dirstate.py` uses `status()` for a number of things with the `match` specified as a filter, so the output of `status()` must be filtered by `match` accordingly. Ultimately, this seems like work that would be better done on the server, but for simplicity, we're just going to do it in Python, for now. For the reasons explained above, this revision deletes a lot of code `Dirstate.cpp`. As such, `DirstateTest.cpp` does not seem worth refactoring, though the scenarios it was testing should probably be converted to integration tests. At a high level, the role of `DirstatePersistence` has not changed, but the exact data it writes is much different. Its corresponding unit test is also disabled, for now. Note that this revision does not change the name of the file where "dirstate data" is written (this is defined as `kDirstateFile` in `ClientConfig.cpp`), so we should blow away any existing instances of this file once this change lands. (It is still early enough in the project that it does not seem worth the overhead of a proper migration.) The true test of the success of this new approach is the ease with which we can write more integration tests for things like `hg histedit` and `hg graft`. Ideally, these should require very few changes to `eden_dirstate.py`. Reviewed By: simpkins Differential Revision: D5071778 fbshipit-source-id: e8fec4d393035d80f36516ac050cad025dc3ba31
2017-05-26 21:51:30 +03:00
void hgSetDirstateTuple(
std::unique_ptr<std::string> mountPoint,
Reimplement dirstate used by Eden's Hg extension as a subclass of Hg's dirstate. Summary: This is a major change to Eden's Hg extension. Our initial attempt to implement `edendirstate` was to create a "clean room" implementation that did not share code with `mercurial/dirstate.py`. This was helpful in uncovering the subset of the dirstate API that matters for Eden. It also provided a better safeguard against upstream changes to `dirstate.py` in Mercurial itself. In this implementation, the state transition management was mostly done on the server in `Dirstate.cpp`. We also made a modest attempt to make `Dirstate.cpp` "SCM-agnostic" such that the same APIs could be used for Git at some point. However, as we have tried to support more of the sophisticated functionality in Mercurial, particularly `hg histedit`, achieving parity between the clean room implementation and Mercurial's internals has become more challenging. Ultimately, the clean room implementation is likely the right way to go for Eden, but for now, we need to prioritize having feature parity with vanilla Hg when using Eden. Once we have a more complete set of integration tests in place, we can reimplement Eden's dirstate more aggressively to optimize things. Fortunately, the [[ https://bitbucket.org/facebook/hg-experimental/src/default/sqldirstate/ | sqldirstate ]] extension has already demonstrated that it is possible to provide a faithful dirstate implementation that subclasses the original `dirstate` while using a different storage mechanism. As such, I used `sqldirstate` as a model when implementing the new `eden_dirstate` (distinguishing it from our v1 implementation, `edendirstate`). In particular, `sqldirstate` uses SQL tables as storage for the following private fields of `dirstate`: `_map`, `_dirs`, `_copymap`, `_filefoldmap`, `_dirfoldmap`. Because `_filefoldmap` and `_dirfoldmap` exist to deal with case-insensitivity issues, we do not support them in `eden_dirstate` and add code to ensure the codepaths that would access them in `dirstate` never get exercised. Similarly, we also implemented `eden_dirstate` so that it never accesses `_dirs`. (`_dirs` is a multiset of all directories in the dirstate, which is an O(repo) data structure, so we do not want to maintain it in Eden. It appears to be primarily used for checking whether a path to a file already exists in the dirstate as a directory. We can protect against that in more efficient ways.) That leaves only `_map` and `_copymap` to worry about. `_copymap` contains the set of files that have been marked "copied" in the current dirstate, so it is fairly small and can be stored on disk or in memory with little concern. `_map` is a bit trickier because it is expected to have an entry for every file in the dirstate. In `sqldirstate`, it is stored across two tables: `files` and `nonnormalfiles`. For Eden, we already represent the data analogous to the `files` table in RocksDB/the overlay, so we do not need to create a new equivalent to the `files` table. We do, however, need an equivalent to the `nonnormalfiles` table, which we store in as Thrift-serialized data in an ordinary file along with the `_copymap` data. In our Hg extension, our implementation of `_map` is `eden_dirstate_map`, which is defined in a Python file of the same name. Our implementation of `_copymap` is `dummy_copymap`, which is defined in `eden_dirstate.py`. Both of these collections are simple pass-through data structures that translate their method calls to Thrift server calls. I expect we will want to optimize this in the future via some client-side caching, as well as creating batch APIs for talking to the server via Thrift. One advantage of this new implementation is that it enables us to delete `eden/hg/eden/overrides.py`, which overrode the entry points for `hg add` and `hg remove`. Between the recent implementation of `dirstate.walk()` for Eden and this switch to the real dirstate, we can now use the default implementation of `hg add` and `hg remove` (although we have to play some tricks, like in the implementation of `eden_dirstate.status()` in order to make `hg remove` work). In the course of doing this revision, I discovered that I had to make a minor fix to `EdenMatchInfo.make_glob_list()` because `hg add foo` was being treated as `hg add foo/**/*` even when `foo` was just a file (as opposed to a directory), in which case the glob was not matching `foo`! I also had to do some work in `eden_dirstate.status()` in which the `match` argument was previously largely ignored. It turns out that `dirstate.py` uses `status()` for a number of things with the `match` specified as a filter, so the output of `status()` must be filtered by `match` accordingly. Ultimately, this seems like work that would be better done on the server, but for simplicity, we're just going to do it in Python, for now. For the reasons explained above, this revision deletes a lot of code `Dirstate.cpp`. As such, `DirstateTest.cpp` does not seem worth refactoring, though the scenarios it was testing should probably be converted to integration tests. At a high level, the role of `DirstatePersistence` has not changed, but the exact data it writes is much different. Its corresponding unit test is also disabled, for now. Note that this revision does not change the name of the file where "dirstate data" is written (this is defined as `kDirstateFile` in `ClientConfig.cpp`), so we should blow away any existing instances of this file once this change lands. (It is still early enough in the project that it does not seem worth the overhead of a proper migration.) The true test of the success of this new approach is the ease with which we can write more integration tests for things like `hg histedit` and `hg graft`. Ideally, these should require very few changes to `eden_dirstate.py`. Reviewed By: simpkins Differential Revision: D5071778 fbshipit-source-id: e8fec4d393035d80f36516ac050cad025dc3ba31
2017-05-26 21:51:30 +03:00
std::unique_ptr<std::string> relativePath,
std::unique_ptr<hgdirstate::DirstateTuple> tuple) override;
void hgGetNonnormalFiles(
std::vector<HgNonnormalFile>& out,
std::unique_ptr<std::string> mountPoint) override;
void hgCopyMapPut(
std::unique_ptr<std::string> mountPoint,
std::unique_ptr<std::string> relativePathDest,
std::unique_ptr<std::string> relativePathSource) override;
void hgCopyMapGet(
std::string& relativePathSource,
std::unique_ptr<std::string> mountPoint,
std::unique_ptr<std::string> relativePathDest) override;
void hgCopyMapGetAll(
std::map<std::string, std::string>& copyMap,
std::unique_ptr<std::string> mountPoint) override;
void debugGetScmTree(
std::vector<ScmTreeEntry>& entries,
std::unique_ptr<std::string> mountPoint,
std::unique_ptr<std::string> id,
bool localStoreOnly) override;
void debugGetScmBlob(
std::string& data,
std::unique_ptr<std::string> mountPoint,
std::unique_ptr<std::string> id,
bool localStoreOnly) override;
void debugGetScmBlobMetadata(
ScmBlobMetadata& metadata,
std::unique_ptr<std::string> mountPoint,
std::unique_ptr<std::string> id,
bool localStoreOnly) override;
void debugInodeStatus(
std::vector<TreeInodeDebugInfo>& inodeInfo,
std::unique_ptr<std::string> mountPoint,
std::unique_ptr<std::string> path) override;
void unloadInodeForPath(
std::unique_ptr<std::string> mountPoint,
std::unique_ptr<std::string> path) override;
/**
* When this Thrift handler is notified to shutdown, it notifies the
* EdenServer to shut down, as well.
*/
void shutdown() override;
private:
// Forbidden copy constructor and assignment operator
EdenServiceHandler(EdenServiceHandler const&) = delete;
EdenServiceHandler& operator=(EdenServiceHandler const&) = delete;
folly::Future<Hash> getSHA1ForPath(
folly::StringPiece mountPoint,
folly::StringPiece path);
folly::Future<Hash> getSHA1ForPathDefensively(
folly::StringPiece mountPoint,
folly::StringPiece path) noexcept;
void mountImpl(const MountInfo& info);
AbsolutePath getPathToDirstateStorage(AbsolutePathPiece mountPointPath);
EdenServer* const server_;
};
}
} // facebook::eden