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liminal_server/
error.rs

1use std::net::SocketAddr;
2
3use crate::server::participant::ParticipantServiceFatal;
4
5/// Error taxonomy for standalone liminal server deployment failures.
6#[derive(Debug, thiserror::Error)]
7pub enum ServerError {
8    /// The configuration file could not be read or parsed.
9    #[error("configuration load failed: {message}")]
10    ConfigLoad { message: String },
11
12    /// The configuration file was read but failed semantic validation.
13    #[error("configuration validation failed: {message}")]
14    ConfigValidation { message: String },
15
16    /// The server could not bind its configured listener address.
17    #[error("listener bind failed for {address}: {source}")]
18    ListenerBind {
19        /// Address the server attempted to bind.
20        address: SocketAddr,
21        /// Underlying operating-system bind failure.
22        #[source]
23        source: std::io::Error,
24    },
25
26    /// The server listener failed while accepting an inbound connection.
27    #[error("listener accept failed: {message}")]
28    ListenerAccept { message: String },
29
30    /// Durable participant-incarnation startup or allocation failed before its
31    /// result could be published.
32    #[error("participant incarnation {phase} failed: {message}")]
33    ParticipantIncarnation {
34        /// Exact server seam that failed.
35        phase: &'static str,
36        /// Underlying durable or bounded-bridge diagnostic.
37        message: String,
38    },
39
40    /// A durable connection-fate Open could not be completed in this process.
41    ///
42    /// The normal runtime shutdown path returns this typed fatal only after it has
43    /// stopped both listeners and run the ordinary connection drain/flush sequence.
44    #[error("participant service fatal: {fatal}")]
45    ParticipantServiceFatal {
46        /// First process-wide post-Open failure; later failures cannot replace it.
47        fatal: ParticipantServiceFatal,
48    },
49
50    /// Startup found durable connection-fate work that the Decision A/C producer must complete
51    /// before listener or semantic-service publication.
52    #[error(
53        "participant startup requires recovery of {open_count} connection-fate Opens beginning at sequence {first_open_sequence}"
54    )]
55    ConnectionFateRecoveryRequired {
56        /// Number of replay-validated unmatched Opens.
57        open_count: usize,
58        /// Lowest unmatched Open sequence.
59        first_open_sequence: u64,
60    },
61
62    /// The durable server-incarnation namespace has no successor.
63    #[error("participant server-incarnation namespace is exhausted")]
64    ServerIncarnationExhausted,
65
66    /// Production participant startup restore failed: the durable
67    /// conversation streams could not be scanned or replayed, so the
68    /// server-scope capacity ledger cannot be made exact and the server
69    /// refuses to start over state it cannot account for.
70    #[error("participant startup restore failed: {message}")]
71    ParticipantStartupRestore {
72        /// Underlying durable, replay, or bridge diagnostic.
73        message: String,
74    },
75
76    /// The current durable server incarnation has no collision-free connection
77    /// ordinal left, so the accepted socket was not admitted.
78    #[error(
79        "connection incarnation exhausted for server incarnation {attempted_server_incarnation}"
80    )]
81    ConnectionIncarnationExhausted {
82        /// Server incarnation whose complete ordinal suffix was examined.
83        attempted_server_incarnation: u64,
84    },
85
86    /// A frame requested an operation the configured services profile does not
87    /// serve (e.g. ordinary publish/subscribe/conversation traffic against the
88    /// capability-scoped worker front door). Server-internal taxonomy, not wire
89    /// vocabulary: the connection process renders it as the operation's existing
90    /// typed error frame with this error's text as the message.
91    #[error("{operation} is not supported by the {profile} services profile")]
92    UnsupportedOperation {
93        /// Human-readable description of the refused operation.
94        operation: String,
95        /// The configured services profile that refused it.
96        profile: &'static str,
97    },
98
99    /// A server→client push reply slot was dropped before a correlated reply
100    /// arrived — the connection closed (the prompt worker-death signal). Distinct
101    /// from [`Self::PushReplyTimeout`] so consumers can tell a worker that DIED
102    /// (fast failover) from one that is merely SLOW, by type rather than message.
103    #[error(
104        "push correlation {correlation_id} did not complete: the connection closed before sending a correlated push reply"
105    )]
106    PushReplyDisconnected {
107        /// Correlation id of the push whose reply will never arrive.
108        correlation_id: u64,
109    },
110
111    /// A server→client push reply did not arrive within the awaiter's timeout —
112    /// the worker is still connected but did not reply in this wait quantum. This
113    /// is BENIGN: the reply slot survives untouched and the caller may re-arm
114    /// [`PushReplyAwaiter::receive`](crate::server::connection::PushReplyAwaiter::receive)
115    /// indefinitely. It is not a worker-death signal.
116    #[error(
117        "push correlation {correlation_id} did not complete: no correlated push reply arrived within the timeout"
118    )]
119    PushReplyTimeout {
120        /// Correlation id of the push whose wait quantum elapsed.
121        correlation_id: u64,
122    },
123
124    /// A server→client push carrying an explicit reply deadline (via
125    /// [`push_to_connection_with_deadline`](crate::server::connection::ConnectionSupervisor::push_to_connection_with_deadline))
126    /// reached that deadline before a correlated reply arrived. Unlike
127    /// [`Self::PushReplyTimeout`] this is TERMINAL: the reply slot has been
128    /// removed and its §5 `max_pending_pushes_per_connection` cap admission
129    /// released. Returned PROMPTLY once the deadline is due — a `receive` call
130    /// does not hold a due expiry until its caller's quantum ends, so the
131    /// terminal outcome is independent of how the caller polls. Distinct
132    /// variant so callers classify by type, not message.
133    #[error(
134        "push correlation {correlation_id} did not complete: its reply deadline passed before a correlated push reply arrived"
135    )]
136    PushReplyExpired {
137        /// Correlation id of the push whose reply deadline passed.
138        correlation_id: u64,
139    },
140
141    /// The server could not join the configured beamr distribution cluster.
142    #[error("cluster join failed: {message}")]
143    ClusterJoin { message: String },
144
145    /// Cluster state propagation through beamr distribution failed.
146    #[error("cluster sync failed: {message}")]
147    ClusterSync { message: String },
148
149    /// Graceful shutdown did not drain within the configured timeout.
150    #[error("shutdown timed out: {message}")]
151    ShutdownTimeout { message: String },
152
153    /// Durable state could not be flushed during graceful shutdown.
154    #[error("shutdown flush failed: {message}")]
155    ShutdownFlush { message: String },
156
157    /// The health endpoint failed to start or serve requests.
158    #[error("health endpoint failed: {message}")]
159    HealthEndpoint { message: String },
160
161    /// A new connection was refused because the configured `max_connections`
162    /// cap (§5) is already reached. The listener drops the freshly accepted
163    /// stream, refusing the connection, rather than admitting an unbounded fleet.
164    #[error(
165        "connection refused: the configured max_connections limit of {limit} live connections is reached"
166    )]
167    ConnectionLimitReached {
168        /// The configured `max_connections` cap that was hit.
169        limit: usize,
170    },
171
172    /// An admission-time per-connection cap (§5) refused an operation: too many
173    /// subscriptions, conversations, in-flight pushes, or pending conversation
174    /// replies on one connection. The connection process renders it as the
175    /// operation's existing typed error frame with this text as the message.
176    #[error("{operation} refused: the per-connection {cap} limit of {limit} is reached")]
177    ConnectionCapReached {
178        /// Human-readable description of the refused operation.
179        operation: String,
180        /// The name of the cap that refused it (a `limits.*` config key).
181        cap: &'static str,
182        /// The configured cap value that was hit.
183        limit: usize,
184    },
185}