third-party/watchman/src/watchman/saved_state/SavedStateInterface.h

   1 /*
   2  * Copyright (c) Meta Platforms, Inc. and affiliates.
   3  *
   4  * This source code is licensed under the MIT license found in the
   5  * LICENSE file in the root directory of this source tree.
   6  */
   7
   8 #pragma once
   9
  10 #include "watchman/thirdparty/jansson/jansson.h"
  11
  12 namespace watchman {
  13
  14 class Configuration;
  15 class PerfSample;
  16 class SavedStateInterface;
  17 class SCM;
  18
  19 using SavedStateFactory = std::unique_ptr<SavedStateInterface> (*)(
  20     w_string_piece storageType,
  21     const json_ref& savedStateConfig,
  22     const SCM* scm,
  23     Configuration config,
  24     std::function<void(PerfSample&)> extraSampleMetadata);
  25
  26 // An interface that returns information about saved states associated with
  27 // specific source control commits. Clients using scm-aware queries can
  28 // receive information about the most recent known good saved state when the
  29 // mergebase changes, along with the changed files since that saved state. The
  30 // client can then update the current state based on the saved state and the
  31 // modified files since that state's commit, rather than processing all
  32 // changes since the prior mergebase.
  33 class SavedStateInterface {
  34  public:
  35   virtual ~SavedStateInterface();
  36
  37   // The commit ID of a saved state and a JSON blob of information clients can
  38   // use to access the saved state.  The contents of the info varies with the
  39   // storage type.
  40   struct SavedStateResult {
  41     w_string commitId;
  42     std::optional<json_ref> savedStateInfo;
  43   };
  44   // Returns saved state information for the most recent commit prior to and
  45   // including lookupCommitId that has a valid saved state for the specified
  46   // storage key. The contents of the storage key and the return value vary with
  47   // the storage type.
  48   SavedStateResult getMostRecentSavedState(w_string_piece lookupCommitId) const;
  49
  50  protected:
  51   w_string project_;
  52   w_string projectMetadata_;
  53
  54   explicit SavedStateInterface(const json_ref& savedStateConfig);
  55   virtual SavedStateResult getMostRecentSavedStateImpl(
  56       w_string_piece lookupCommitId) const = 0;
  57 };
  58 } // namespace watchman