健康检查

健康检查是一种标准化的检查指标。如果将 fuchsia.inspect.Health 子级添加到检查节点，则会为该节点提供包含的运行状况信息。这些信息可以通过系统级健康检查工具进行汇总。

健康检查节点的布局

在任何健康检查节点中，都会导出以下属性和指标：

名称 类型 说明
start_timestamp_nanos int64 初始化此健康节点（即首次变为 STARTING UP）时的单调时钟系统时间戳
message 字符串 如果为 status==UNHEALTHY，则包括可选的失败详情消息。
status 枚举 STARTING_UP：
运行状况节点已初始化，但尚未标记为正在运行。
OK：
向此健康节点报告的子系统正在报告健康状况良好。
UNHEALTHY：
向此运行状况节点报告的子系统正在报告运行状况不佳。

用户指南

以下示例说明了如何使用 ffx inspect 获取有关组件运行状况的信息。

示例：

$ ffx inspect show
core/a:
  root:
    fuchsia.inspect.Health:
      start_timestamp_nanos = ...
      status = OK
    connections:
      0:
        fuchsia.inspect.Health:
          start_timestamp_nanos = ...
          status = STARTING_UP
    optional_database:
      fuchsia.inspect.Health:
        start_timestamp_nanos = ...
        status = UNHEALTHY
        message = "Cannot open local.file"
core/a:
  root:
    fuchsia.inspect.Health:
      start_timestamp_nanos = ...
      status = OK
core/a:
  root:
    fuchsia.inspect.Health:
      start_timestamp_nanos = ...
      status = UNHEALTHY
      message = "Failed to connect to fuchsia.example.RequiredService"

$ ffx inspect show a.cm:root/fuchsia.inspect.Health:status b.cm:root/fuchsia.inspect.Healh:status c.cm:root/fuchsia.inspect.Health:status
a:
  root:
    fuchsia.inspectHealth:
      status = OK
b:
  root:
    fuchsia.inspectHealth:
      status = OK
c:
  root:
    fuchsia.inspectHealth:
      status = UNHEALTHY

在组件中使用健康检查

以下部分介绍了如何在采用各种编程语言编写的 Fuchsia 组件中使用该库。

C++

  #include <lib/async-loop/cpp/loop.h>
  #include <lib/async-loop/default.h>
  #include <lib/sys/cpp/component_context.h>
  #include <lib/inspect/component/cpp/component.h>

  int main(int argc, char** argv) {
    async::Loop loop(&kAsyncLoopConfigAttachToCurrentThread);
    auto context = sys::ComponentContext::CreateAndServeOutgoingDirectory();
    inspect::ComponentInspector inspector(loop.dispatcher(), inspect::PublishOptions{});
    inspector.Health().StartingUp();

    // ...Do startup work...

    inspector.Health().Ok();
    inspector.Health().Unhealthy("I'm not feeling well.");
    inspector.Health().Ok();

    loop.Run();
    return 0;
  }

Rust

  use fuchsia_inspect as inspect;
  use fuchsia_inspect::health;

  fn main() {
    // If you have your own inspector, it's also possible to export its health.

    /* inspector needs to be initialized */
    let inspector = /* ... */
    let mut node = inspector::root();
    let mut health = fuchsia_inspect::health::Node(node);
    // ...
    health.set_ok();
    health.set_unhealthy("I'm not feeling well.");
    health.set_ok();  // The component is healthy again.
  }