如何捕获稍纵即逝的 bazel 控制台输出

Question

在 bazel 构建期间，有一堆文本飞过，这些文本临时显示，然后从屏幕上删除。这发生在整个构建过程中。我尝试了几种重定向技术，将 stderr 重定向到标准输出，但无济于事。我还尝试了 bazel 的详细标志。

问题：有没有办法捕获 bazel 生成的这个稍纵即逝的控制台输出？我想至少在信息被带走之前研究一下所呈现的信息，更多的是作为一种学习练习并获得熟悉。

Answer 1

这些选项应该允许您扩展由操作/任务生成的所有日志消息并将它们重定向到文件。

# .bazelrc
common --color=no
common --curses=yes

build --show_progress_rate_limit=0
build --show_task_finish
build --show_timestamps
build --worker_verbose

设置color=no并show_progress_rate_limit=0导致要在终端中扩展（并保留）的进度消息。 curses=yes影响重定向（至少在我的机器上）。其他标志只是向日志添加更多信息。

示例输出（bash、bazel 1.0.0）

$> bazel build :my_project >& /tmp/bazel_build.log
$> cat /tmp/bazel_build.log

(11:22:46) INFO: Writing tracer profile to '.../command.profile.gz'
(11:22:46) INFO: Current date is 2019-11-01
(11:22:46) Loading: loading...
(11:22:46) Loading: 
(11:22:46) Loading: 0 packages loaded
(11:22:46) Loading: 0 packages loaded
    Fetching @bazel_tools; fetching

(11:22:46) Loading: 0 packages loaded
    Fetching @bazel_tools; fetching

(11:22:46) Loading: 0 packages loaded
    currently loading: path/to/my/project

(11:22:46) Analyzing: target //path/to/my/project:my_project (1 packages l\
oaded)

[...]

(11:22:46) INFO: Analyzed target //path/to/my/project:my_project (14 packages loaded, 670 targets configured).
(11:22:46) 
(11:22:46) INFO: Found 1 target...
(11:22:46) 
(11:22:46) [0 / 1] [Prepa] BazelWorkspaceStatusAction stable-status.txt
(11:22:46) [1 / 13] [Prepa] //path/to/my/project:my_project
(11:22:46) [5 / 12] 3 actions, 0 running
    [Prepa] @deps//:my_dependency

(11:22:46) [10 / 12] [Scann] Compiling path/to/my/project/main.cc
(11:22:46) [10 / 12] [Prepa] Compiling path/to/my/project/main.cc
(11:22:46) [10 / 12] .../project:my_project; 0s processwrapper-sandbox

(11:22:46) [11 / 12] [Prepa] Linking path/to/my/project/my_project
Target //path/to/my/project:my_project up-to-date:
(11:22:46) [12 / 12] checking cached actions
  bazel-bin/path/to/my/project/my_project
(11:22:46) [12 / 12] checking cached actions
(11:22:46) INFO: Elapsed time: 0.493s, Critical Path: 0.29s
(11:22:46) [12 / 12] checking cached actions
(11:22:46) INFO: 2 processes: 2 processwrapper-sandbox.
(11:22:46) [12 / 12] checking cached actions
(11:22:46) INFO: Build completed successfully, 12 total actions
(11:22:46) INFO: Build completed successfully, 12 total actions

希望这可以帮助。