persistence/
lib.rs

1// Copyright 2020 The Fuchsia Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5//! `diagnostics-persistence` component persists Inspect VMOs and serves them at the next boot.
6
7mod constants;
8mod fetcher;
9mod file_handler;
10mod inspect_server;
11mod persist_server;
12mod scheduler;
13
14use anyhow::{bail, Error};
15use argh::FromArgs;
16use fetcher::Fetcher;
17use fuchsia_async as fasync;
18use fuchsia_component::server::{ServiceFs, ServiceObj};
19use fuchsia_inspect::component;
20use fuchsia_inspect::health::Reporter;
21use futures::StreamExt;
22use log::*;
23use persist_server::PersistServer;
24use persistence_config::Config;
25use scheduler::Scheduler;
26use zx::BootInstant;
27
28/// The name of the subcommand and the logs-tag.
29pub const PROGRAM_NAME: &str = "persistence";
30pub const PERSIST_NODE_NAME: &str = "persist";
31/// Added after persisted data is fully published
32pub const PUBLISHED_TIME_KEY: &str = "published";
33
34/// Command line args
35#[derive(FromArgs, Debug, PartialEq)]
36#[argh(subcommand, name = "persistence")]
37pub struct CommandLine {}
38
39// on_error logs any errors from `value` and then returns a Result.
40// value must return a Result; error_message must contain one {} to put the error in.
41macro_rules! on_error {
42    ($value:expr, $error_message:expr) => {
43        $value.or_else(|e| {
44            let message = format!($error_message, e);
45            warn!("{}", message);
46            bail!("{}", message)
47        })
48    };
49}
50
51pub async fn main(_args: CommandLine) -> Result<(), Error> {
52    info!("Starting Diagnostics Persistence Service service");
53    let mut health = component::health();
54    let config =
55        on_error!(persistence_config::load_configuration_files(), "Error loading configs: {}")?;
56    let inspector = component::inspector();
57    let _inspect_server_task =
58        inspect_runtime::publish(inspector, inspect_runtime::PublishOptions::default());
59
60    info!("Rotating directories");
61    file_handler::shuffle_at_boot();
62
63    let mut fs = ServiceFs::new();
64
65    // Create the Inspect fetcher
66    let (fetch_requester, _fetcher_task) =
67        on_error!(Fetcher::new(&config), "Error initializing fetcher: {}")?;
68
69    let scheduler = Scheduler::new(fetch_requester, &config);
70
71    // Add a persistence fidl service for each service defined in the config files.
72    let scope = fasync::Scope::new();
73    let service_scope = scope.new_child_with_name("services");
74    spawn_persist_services(&config, &mut fs, scheduler, &service_scope);
75
76    fs.take_and_serve_directory_handle()?;
77    scope.spawn(fs.collect::<()>());
78
79    // Before serving previous data, wait until the post-boot system update check has finished.
80    // Note: We're already accepting persist requests. If we receive a request, store
81    // some data, and then cache is cleared after data is persisted, that data will be lost. This
82    // is correct behavior - we don't want to remember anything from before the cache was cleared.
83    scope.spawn(async move {
84        info!("Waiting for post-boot update check...");
85        match fuchsia_component::client::connect_to_protocol::<fidl_fuchsia_update::ListenerMarker>(
86        ) {
87            Ok(proxy) => match proxy.wait_for_first_update_check_to_complete().await {
88                Ok(()) => {}
89                Err(e) => {
90                    warn!(e:?; "Error waiting for first update check; not publishing.");
91                    return;
92                }
93            },
94            Err(e) => {
95                warn!(
96                    e:?;
97                    "Unable to connect to fuchsia.update.Listener; will publish immediately."
98                );
99            }
100        }
101        // Start serving previous boot data
102        info!("...Update check has completed; publishing previous boot data");
103        inspector.root().record_child(PERSIST_NODE_NAME, |node| {
104            inspect_server::serve_persisted_data(node);
105            health.set_ok();
106            info!("Diagnostics Persistence Service ready");
107        });
108        inspector.root().record_int(PUBLISHED_TIME_KEY, BootInstant::get().into_nanos());
109    });
110
111    scope.await;
112
113    Ok(())
114}
115
116// Takes a config and adds all the persist services defined in those configs to the servicefs of
117// the component.
118fn spawn_persist_services(
119    config: &Config,
120    fs: &mut ServiceFs<ServiceObj<'static, ()>>,
121    scheduler: Scheduler,
122    scope: &fasync::Scope,
123) {
124    let mut started_persist_services = 0;
125
126    for (service_name, tags) in config {
127        info!("Launching persist service for {service_name}");
128        let unique_service_name =
129            format!("{}-{}", constants::PERSIST_SERVICE_NAME_PREFIX, service_name);
130
131        let server = PersistServer::create(
132            service_name.clone(),
133            tags.keys().cloned().collect(),
134            scheduler.clone(),
135            // Fault tolerance if only a subset of the service configs fail to initialize.
136            scope.new_child_with_name(&service_name.clone()),
137        );
138        fs.dir("svc").add_fidl_service_at(unique_service_name, move |stream| {
139            server.spawn(stream);
140        });
141        started_persist_services += 1;
142    }
143
144    info!("Started {} persist services", started_persist_services);
145}
persistence/lib.rs

persistence/
lib.rs
