輸出內容目錄版面配置

回報問題 查看來源 Nightly · 8.3 · 8.2 · 8.1 · 8.0 · 7.6

本頁說明輸出目錄的需求和版面配置。

需求條件

輸出目錄版面配置規定:

  • 如果多位使用者在同一個方塊上建構,不會發生衝突。
  • 支援同時在多個工作區中建構。
  • 支援在同一個工作區中,為多個目標設定建構。
  • 不會與任何其他工具發生衝突。
  • 方便存取。
  • 可輕鬆清除,甚至選擇性清除。
  • 即使使用者在變更為用戶端目錄時依賴符號連結,也不會造成混淆。
  • 每個使用者的所有建構狀態都應位於一個目錄下 (「我想清除所有用戶端的所有 .o 檔案。」)

目前版面配置

目前採用的解決方案:

  • 必須從包含存放區界線檔案的目錄或其子目錄中叫用 Bazel。換句話說,您必須從存放區內叫用 Bazel。否則會回報錯誤。
  • outputRoot 目錄在 Linux 上預設為 ~/.cache/bazel,在 macOS 上預設為 /private/var/tmp,在 Windows 上則預設為 %HOME% (如果已設定),否則為 %USERPROFILE% (如果已設定),否則為呼叫 SHGetKnownFolderPath() 並設定 FOLDERID_Profile 旗標的結果。如果在 Linux 或 macOS 上設定環境變數 $XDG_CACHE_HOME,值 ${XDG_CACHE_HOME}/bazel 會覆寫預設值。如果已設定環境變數 $TEST_TMPDIR (例如在 Bazel 本身的測試中),該值會覆寫所有預設值。
  • Bazel 使用者的建構狀態位於 outputRoot/_bazel_$USER 下方。這個目錄稱為 outputUserRoot
  • outputUserRoot 目錄下方有一個 install 目錄,其中包含一個 installBase 目錄,名稱是 Bazel 安裝資訊清單的 MD5 雜湊值。
  • outputUserRoot 目錄下方,系統也會建立 outputBase 目錄,其名稱是工作區根目錄路徑名稱的 MD5 雜湊值。舉例來說,如果 Bazel 在工作區根目錄 /home/user/src/my-project (或連結至該目錄的目錄) 中執行,系統就會建立名為 /home/user/.cache/bazel/_bazel_user/7ffd56a6e4cb724ea575aba15733d113 的輸出基礎目錄。您也可以在工作區根目錄中執行 echo -n $(pwd) | md5sum 來取得 MD5。
  • 您可以使用 Bazel 的 --output_base 啟動選項,覆寫預設輸出基本目錄。例如 bazel --output_base=/tmp/bazel/output build x/y:z
  • 您也可以使用 Bazel 的 --output_user_root 啟動選項,覆寫預設的安裝基礎和輸出基礎目錄。例如: bazel --output_user_root=/tmp/bazel build x/y:z

「bazel-<workspace-name>」、「bazel-out」、「bazel-testlogs」和「bazel-bin」的符號連結會放在工作區目錄中;這些符號連結會指向輸出目錄中目標專屬目錄內的某些目錄。這些符號連結僅為方便使用者而設,因為 Bazel 本身不會使用這些連結。此外,只有在工作區根目錄可寫入時,才會執行這項操作。

版面配置圖

目錄結構如下:

<workspace-name>/                         <== The workspace root
  bazel-my-project => <..._main>          <== Symlink to execRoot
  bazel-out => <...bazel-out>             <== Convenience symlink to outputPath
  bazel-bin => <...bin>                   <== Convenience symlink to most recent written bin dir $(BINDIR)
  bazel-testlogs => <...testlogs>         <== Convenience symlink to the test logs directory

/home/user/.cache/bazel/                  <== Root for all Bazel output on a machine: outputRoot
  _bazel_$USER/                           <== Top level directory for a given user depends on the user name:
                                              outputUserRoot
    install/
      fba9a2c87ee9589d72889caf082f1029/   <== Hash of the Bazel install manifest: installBase
        _embedded_binaries/               <== Contains binaries and scripts unpacked from the data section of
                                              the bazel executable on first run (such as helper scripts and the
                                              main Java file BazelServer_deploy.jar)
    7ffd56a6e4cb724ea575aba15733d113/     <== Hash of the client's workspace root (such as
                                              /home/user/src/my-project): outputBase
      action_cache/                       <== Action cache directory hierarchy
                                              This contains the persistent record of the file
                                              metadata (timestamps, and perhaps eventually also MD5
                                              sums) used by the FilesystemValueChecker.
      command.log                         <== A copy of the stdout/stderr output from the most
                                              recent bazel command.
      external/                           <== The directory that remote repositories are
                                              downloaded/symlinked into.
      server/                             <== The Bazel server puts all server-related files (such
                                              as socket file, logs, etc) here.
        jvm.out                           <== The debugging output for the server.
      execroot/                           <== The working directory for all actions. For special
                                              cases such as sandboxing and remote execution, the
                                              actions run in a directory that mimics execroot.
                                              Implementation details, such as where the directories
                                              are created, are intentionally hidden from the action.
                                              Every action can access its inputs and outputs relative
                                              to the execroot directory.
        _main/                            <== Working tree for the Bazel build & root of symlink forest: execRoot
          _bin/                           <== Helper tools are linked from or copied to here.

          bazel-out/                      <== All actual output of the build is under here: outputPath
            _tmp/actions/                 <== Action output directory. This contains a file with the
                                              stdout/stderr for every action from the most recent
                                              bazel run that produced output.
            local_linux-fastbuild/        <== one subdirectory per unique target BuildConfiguration instance;
                                              this is currently encoded
              bin/                        <== Bazel outputs binaries for target configuration here: $(BINDIR)
                foo/bar/_objs/baz/        <== Object files for a cc_* rule named //foo/bar:baz
                  foo/bar/baz1.o          <== Object files from source //foo/bar:baz1.cc
                  other_package/other.o   <== Object files from source //other_package:other.cc
                foo/bar/baz               <== foo/bar/baz might be the artifact generated by a cc_binary named
                                              //foo/bar:baz
                foo/bar/baz.runfiles/     <== The runfiles symlink farm for the //foo/bar:baz executable.
                  MANIFEST
                  _main/
                    ...
              genfiles/                   <== Bazel puts generated source for the target configuration here:
                                              $(GENDIR)
                foo/bar.h                     such as foo/bar.h might be a headerfile generated by //foo:bargen
              testlogs/                   <== Bazel internal test runner puts test log files here
                foo/bartest.log               such as foo/bar.log might be an output of the //foo:bartest test with
                foo/bartest.status            foo/bartest.status containing exit status of the test (such as
                                              PASSED or FAILED (Exit 1), etc)
            host/                         <== BuildConfiguration for build host (user's workstation), for
                                              building prerequisite tools, that will be used in later stages
                                              of the build (ex: Protocol Compiler)
        <packages>/                       <== Packages referenced in the build appear as if under a regular workspace

*.runfiles 目錄的版面配置詳情,請參閱 RunfilesSupport 指向的位置。

bazel clean

bazel clean 會對 outputPathaction_cache 目錄執行 rm -rf。工作區符號連結也會一併移除。--expunge 選項會清除整個 outputBase。