ic_testkit/pic/
standalone_recipe.rs

1use std::io;
2
3use ic_platform_types::principal::ExternalPrincipal as Principal;
4
5use super::{
6    CachedPocketIcBaseline, CanisterSnapshotTarget, FailureDisposition, PocketIcBaselineRecipe,
7    PreparedBaseline, RebuildReason, ResetPolicies, ResetReceipt, ResetRequirements,
8    SnapshotRestoreFunding, StandaloneCanisterFixture, is_dead_pocket_ic_transport_error,
9};
10
11/// Snapshot-only recipe for one caller-built, installed canister.
12///
13/// Use with [`super::CachedPocketIcBaselinePool`]. The baseline metadata is the
14/// installed canister ID; calls go through the baseline's borrowed `PocketIC`.
15/// The builder owns initialization and readiness before capture and must produce
16/// the same topology and seeded state for every slot of this recipe. It returns
17/// `io::Result<StandaloneCanisterFixture>`; build errors retain their original
18/// cause and are reported at the pool's build stage, without invoking capture.
19///
20/// Only the captured canister is restored. Time, other canisters, pending work
21/// and external resources are not reset. Use a custom recipe or a fresh instance
22/// when those mutations matter. Funding is applied immediately before restore.
23/// This recipe stops/drains its single canister before capture and warm restore,
24/// then starts it at readiness. Automatic progress must remain disabled.
25/// Non-transport restore failures are fatal: the pool discards the affected
26/// baseline before returning the error. Dead transport permits one recovery build.
27pub struct StandaloneCanisterRecipe<B> {
28    requirements: ResetRequirements,
29    build: B,
30}
31
32impl<B> StandaloneCanisterRecipe<B> {
33    /// Describe a single-canister recipe without invoking its builder.
34    ///
35    /// Static suites can initialize the recipe and pool with [`std::sync::LazyLock`].
36    #[must_use]
37    pub fn new(funding: SnapshotRestoreFunding, build: B) -> Self {
38        Self {
39            requirements: ResetRequirements {
40                funding,
41                policies: ResetPolicies::default(),
42            },
43            build,
44        }
45    }
46}
47
48impl<B> PocketIcBaselineRecipe for StandaloneCanisterRecipe<B>
49where
50    B: Fn() -> io::Result<StandaloneCanisterFixture> + Send + Sync + 'static,
51{
52    type Metadata = Principal;
53    // Retain the typed snapshot/contract cause without another error vocabulary.
54    type Error = io::Error;
55
56    fn reset_requirements(&self) -> &ResetRequirements {
57        &self.requirements
58    }
59
60    fn build(&self) -> Result<CachedPocketIcBaseline<Principal>, io::Error> {
61        let (pocket_ic, canister_id) = (self.build)()?.into_parts();
62        pocket_ic
63            .instance()
64            .stop_canister(canister_id, None)
65            .map_err(|source| {
66                io::Error::other(super::ControllerSnapshotError::CaptureFailed {
67                    canister_id,
68                    sender: None,
69                    source: Box::new(source),
70                    cleanup_failures: Vec::new(),
71                })
72            })?;
73        let baseline = CachedPocketIcBaseline::capture(
74            pocket_ic,
75            [CanisterSnapshotTarget {
76                canister_id,
77                sender: None,
78            }],
79            canister_id,
80        )
81        .map_err(io::Error::other)?;
82        self.drive_to_readiness(&baseline)?;
83        Ok(baseline)
84    }
85
86    fn reset_non_snapshot_state(
87        &self,
88        _baseline: &CachedPocketIcBaseline<Principal>,
89    ) -> Result<ResetReceipt, io::Error> {
90        Ok(ResetReceipt::default())
91    }
92
93    fn prepare_restore(
94        &self,
95        baseline: &CachedPocketIcBaseline<Principal>,
96    ) -> Result<(), io::Error> {
97        baseline
98            .pocket_ic()
99            .stop_canister(*baseline.metadata(), None)
100            .map_err(io::Error::other)
101    }
102
103    fn drive_to_readiness(
104        &self,
105        baseline: &CachedPocketIcBaseline<Principal>,
106    ) -> Result<(), io::Error> {
107        baseline
108            .pocket_ic()
109            .start_canister(*baseline.metadata(), None)
110            .map_err(io::Error::other)
111    }
112
113    fn validate(
114        &self,
115        _baseline: &CachedPocketIcBaseline<Principal>,
116        _preparation: &PreparedBaseline,
117    ) -> Result<(), io::Error> {
118        Ok(())
119    }
120
121    fn classify_failure(
122        &self,
123        _stage: super::BaselinePreparationStage,
124        error: &(dyn std::error::Error + 'static),
125    ) -> FailureDisposition {
126        if is_dead_pocket_ic_transport_error(error) {
127            FailureDisposition::Rebuild(RebuildReason::DeadPocketIcTransport)
128        } else {
129            FailureDisposition::Fatal
130        }
131    }
132}
133
134#[cfg(test)]
135mod tests {
136    use std::num::NonZeroUsize;
137
138    use super::*;
139    use crate::pic::CachedPocketIcBaselinePool;
140
141    fn build_fixture() -> io::Result<StandaloneCanisterFixture> {
142        panic!("constructing an empty pool must not invoke its builder")
143    }
144
145    #[test]
146    fn runtime_capacity_preserves_lazy_fixture_construction() {
147        for capacity in [1, 2, 4, 8].map(|value| NonZeroUsize::new(value).unwrap()) {
148            let recipe = StandaloneCanisterRecipe::new(
149                SnapshotRestoreFunding::TopUpTo { minimum_cycles: 1 },
150                build_fixture,
151            );
152            let pool = CachedPocketIcBaselinePool::new(capacity, recipe);
153            assert_eq!(pool.capacity(), capacity);
154        }
155    }
156
157    #[test]
158    fn builder_errors_preserve_the_cause_and_release_the_slot_for_another_attempt() {
159        let recipe = StandaloneCanisterRecipe::new(SnapshotRestoreFunding::Preserve, || {
160            Err(io::Error::new(
161                io::ErrorKind::PermissionDenied,
162                std::fmt::Error,
163            ))
164        });
165        let pool = CachedPocketIcBaselinePool::new(NonZeroUsize::new(1).unwrap(), recipe);
166        for _ in 0..2 {
167            let Err(super::super::BaselinePoolError::Preparation {
168                error:
169                    super::super::BaselinePoolPreparationError::Recipe {
170                        stage: super::super::BaselinePreparationStage::Build,
171                        source,
172                    },
173                timings,
174            }) = pool.acquire()
175            else {
176                panic!("builder failure must return at the build stage");
177            };
178            assert_eq!(source.kind(), io::ErrorKind::PermissionDenied);
179            assert!(source.get_ref().unwrap().is::<std::fmt::Error>());
180            assert!(timings.build().is_some());
181            assert!(timings.restore().is_none());
182            assert!(timings.total() >= timings.build().unwrap());
183        }
184    }
185}
ic_testkit/pic/standalone_recipe.rs

ic_testkit/pic/
standalone_recipe.rs
