canic_backup/discovery/
mod.rs

1use crate::{
2    manifest::{FleetMember, FleetSection, IdentityMode, SourceSnapshot, VerificationCheck},
3    topology::{TopologyHasher, TopologyRecord},
4};
5use serde_json::Value;
6use std::collections::{BTreeMap, BTreeSet, VecDeque};
7use thiserror::Error as ThisError;
8
9///
10/// DiscoveredFleet
11///
12
13#[derive(Clone, Debug)]
14pub struct DiscoveredFleet {
15    pub topology_records: Vec<TopologyRecord>,
16    pub members: Vec<DiscoveredMember>,
17}
18
19impl DiscoveredFleet {
20    /// Convert discovered topology and member policy into a manifest fleet section.
21    pub fn into_fleet_section(self) -> Result<FleetSection, DiscoveryError> {
22        validate_discovered_members(&self.members)?;
23
24        let topology_hash = TopologyHasher::hash(&self.topology_records);
25        let members = self
26            .members
27            .into_iter()
28            .map(DiscoveredMember::into_fleet_member)
29            .collect();
30
31        Ok(FleetSection {
32            topology_hash_algorithm: topology_hash.algorithm,
33            topology_hash_input: topology_hash.input,
34            discovery_topology_hash: topology_hash.hash.clone(),
35            pre_snapshot_topology_hash: topology_hash.hash.clone(),
36            topology_hash: topology_hash.hash,
37            members,
38        })
39    }
40}
41
42///
43/// DiscoveredMember
44///
45
46#[derive(Clone, Debug)]
47pub struct DiscoveredMember {
48    pub role: String,
49    pub canister_id: String,
50    pub parent_canister_id: Option<String>,
51    pub subnet_canister_id: Option<String>,
52    pub controller_hint: Option<String>,
53    pub identity_mode: IdentityMode,
54    pub verification_checks: Vec<VerificationCheck>,
55    pub snapshot_plan: SnapshotPlan,
56}
57
58impl DiscoveredMember {
59    /// Project this discovery member into the manifest restore contract.
60    fn into_fleet_member(self) -> FleetMember {
61        FleetMember {
62            role: self.role,
63            canister_id: self.canister_id,
64            parent_canister_id: self.parent_canister_id,
65            subnet_canister_id: self.subnet_canister_id,
66            controller_hint: self.controller_hint,
67            identity_mode: self.identity_mode,
68            verification_checks: self.verification_checks,
69            source_snapshot: SourceSnapshot {
70                snapshot_id: self.snapshot_plan.snapshot_id,
71                module_hash: self.snapshot_plan.module_hash,
72                wasm_hash: self.snapshot_plan.wasm_hash,
73                code_version: self.snapshot_plan.code_version,
74                artifact_path: self.snapshot_plan.artifact_path,
75                checksum_algorithm: self.snapshot_plan.checksum_algorithm,
76                checksum: self.snapshot_plan.checksum,
77            },
78        }
79    }
80}
81
82///
83/// SnapshotPlan
84///
85
86#[derive(Clone, Debug)]
87pub struct SnapshotPlan {
88    pub snapshot_id: String,
89    pub module_hash: Option<String>,
90    pub wasm_hash: Option<String>,
91    pub code_version: Option<String>,
92    pub artifact_path: String,
93    pub checksum_algorithm: String,
94    pub checksum: Option<String>,
95}
96
97///
98/// RegistryEntry
99///
100
101#[derive(Clone, Debug, Eq, PartialEq)]
102pub struct RegistryEntry {
103    pub pid: String,
104    pub role: Option<String>,
105    pub kind: Option<String>,
106    pub parent_pid: Option<String>,
107}
108
109///
110/// SnapshotTarget
111///
112
113#[derive(Clone, Debug, Eq, PartialEq)]
114pub struct SnapshotTarget {
115    pub canister_id: String,
116    pub role: Option<String>,
117    pub parent_canister_id: Option<String>,
118}
119
120///
121/// DiscoveryError
122///
123
124#[derive(Debug, ThisError)]
125pub enum DiscoveryError {
126    #[error("discovered fleet has no members")]
127    EmptyFleet,
128
129    #[error("duplicate discovered canister id {0}")]
130    DuplicateCanisterId(String),
131
132    #[error("discovered member {0} has no verification checks")]
133    MissingVerificationChecks(String),
134
135    #[error("registry JSON must be an array or {{\"Ok\": [...]}}")]
136    InvalidRegistryJsonShape,
137
138    #[error("registry JSON did not contain the requested canister {0}")]
139    CanisterNotInRegistry(String),
140
141    #[error(transparent)]
142    Json(#[from] serde_json::Error),
143}
144
145/// Parse the `dfx --output json` subnet registry shape.
146pub fn parse_registry_entries(registry_json: &str) -> Result<Vec<RegistryEntry>, DiscoveryError> {
147    let data = serde_json::from_str::<Value>(registry_json)?;
148    let entries = data
149        .get("Ok")
150        .and_then(Value::as_array)
151        .or_else(|| data.as_array())
152        .ok_or(DiscoveryError::InvalidRegistryJsonShape)?;
153
154    Ok(entries.iter().filter_map(parse_registry_entry).collect())
155}
156
157/// Resolve selected target and children from registry entries.
158pub fn targets_from_registry(
159    registry: &[RegistryEntry],
160    canister_id: &str,
161    recursive: bool,
162) -> Result<Vec<SnapshotTarget>, DiscoveryError> {
163    let by_pid = registry
164        .iter()
165        .map(|entry| (entry.pid.as_str(), entry))
166        .collect::<BTreeMap<_, _>>();
167
168    let root = by_pid
169        .get(canister_id)
170        .ok_or_else(|| DiscoveryError::CanisterNotInRegistry(canister_id.to_string()))?;
171
172    let mut targets = Vec::new();
173    let mut seen = BTreeSet::new();
174    targets.push(SnapshotTarget {
175        canister_id: root.pid.clone(),
176        role: root.role.clone(),
177        parent_canister_id: root.parent_pid.clone(),
178    });
179    seen.insert(root.pid.clone());
180
181    let mut queue = VecDeque::from([root.pid.clone()]);
182    while let Some(parent) = queue.pop_front() {
183        for child in registry
184            .iter()
185            .filter(|entry| entry.parent_pid.as_deref() == Some(parent.as_str()))
186        {
187            if seen.insert(child.pid.clone()) {
188                targets.push(SnapshotTarget {
189                    canister_id: child.pid.clone(),
190                    role: child.role.clone(),
191                    parent_canister_id: child.parent_pid.clone(),
192                });
193                if recursive {
194                    queue.push_back(child.pid.clone());
195                }
196            }
197        }
198    }
199
200    Ok(targets)
201}
202
203// Parse one registry entry from dfx JSON.
204fn parse_registry_entry(value: &Value) -> Option<RegistryEntry> {
205    let pid = value.get("pid").and_then(Value::as_str)?.to_string();
206    let role = value
207        .get("role")
208        .and_then(Value::as_str)
209        .map(str::to_string);
210    let parent_pid = value
211        .get("record")
212        .and_then(|record| record.get("parent_pid"))
213        .and_then(parse_optional_principal);
214    let kind = value
215        .get("kind")
216        .or_else(|| value.get("record").and_then(|record| record.get("kind")))
217        .and_then(Value::as_str)
218        .map(str::to_string);
219
220    Some(RegistryEntry {
221        pid,
222        role,
223        kind,
224        parent_pid,
225    })
226}
227
228// Parse optional principal JSON emitted as null, string, or optional vector form.
229fn parse_optional_principal(value: &Value) -> Option<String> {
230    if value.is_null() {
231        return None;
232    }
233    if let Some(text) = value.as_str() {
234        return Some(text.to_string());
235    }
236    value
237        .as_array()
238        .and_then(|items| items.first())
239        .and_then(Value::as_str)
240        .map(str::to_string)
241}
242
243// Validate discovery output before building a manifest projection.
244fn validate_discovered_members(members: &[DiscoveredMember]) -> Result<(), DiscoveryError> {
245    if members.is_empty() {
246        return Err(DiscoveryError::EmptyFleet);
247    }
248
249    let mut canister_ids = BTreeSet::new();
250    for member in members {
251        if !canister_ids.insert(member.canister_id.clone()) {
252            return Err(DiscoveryError::DuplicateCanisterId(
253                member.canister_id.clone(),
254            ));
255        }
256        if member.verification_checks.is_empty() {
257            return Err(DiscoveryError::MissingVerificationChecks(
258                member.canister_id.clone(),
259            ));
260        }
261    }
262
263    Ok(())
264}
265
266#[cfg(test)]
267mod tests;
canic_backup/discovery/mod.rs

canic_backup/discovery/
mod.rs
