made_core/
error.rs

1//! Typed domain errors.
2//!
3//! Pure domain errors only. Anything related to I/O, transport, or
4//! serialization belongs to the adapter layer.
5
6use thiserror::Error;
7
8/// All errors that the core domain can raise.
9///
10/// Variants are intentionally coarse-grained at the boundary: each
11/// variant names the invariant that was violated, not the primitive
12/// type involved.
13#[derive(Debug, Clone, PartialEq, Error)]
14pub enum DomainError {
15    /// A required textual field was empty or whitespace-only.
16    #[error("field `{field}` must not be empty")]
17    EmptyField { field: &'static str },
18
19    /// A textual field exceeded its maximum allowed length.
20    #[error("field `{field}` exceeds maximum length: {actual} > {max}")]
21    FieldTooLong {
22        field: &'static str,
23        actual: usize,
24        max: usize,
25    },
26
27    /// A textual field contained characters outside the allowed set.
28    #[error("field `{field}` contains invalid characters")]
29    InvalidCharacters { field: &'static str },
30
31    /// A numeric value fell outside its allowed range.
32    #[error("value `{field}` out of range: {value} not in [{min}, {max}]")]
33    OutOfRange {
34        field: &'static str,
35        value: f64,
36        min: f64,
37        max: f64,
38    },
39
40    /// A numeric value that must be non-zero was zero.
41    #[error("value `{field}` must be non-zero")]
42    MustBeNonZero { field: &'static str },
43
44    /// A collection that must contain at least one element was empty.
45    #[error("collection `{field}` must contain at least one element")]
46    EmptyCollection { field: &'static str },
47
48    /// A state transition was attempted from an invalid state.
49    #[error("invalid state transition `{from}` -> `{to}`")]
50    InvalidTransition {
51        from: &'static str,
52        to: &'static str,
53    },
54
55    /// An aggregate rejected a command because its preconditions were
56    /// not met (e.g. registering an agent into a sealed council).
57    #[error("invariant violated: {reason}")]
58    InvariantViolated { reason: &'static str },
59
60    /// A lookup in a domain registry did not resolve.
61    #[error("not found: {what}")]
62    NotFound { what: &'static str },
63
64    /// A domain entity with the same identity already exists.
65    #[error("already exists: {what}")]
66    AlreadyExists { what: &'static str },
67
68    /// Somebody else changed this first.
69    ///
70    /// A distinct variant rather than an invariant violation, because
71    /// the two ask different things of a caller. An invariant that was
72    /// violated will be violated again by the same call; a conflict is
73    /// the expected outcome of two callers reaching the same thing at
74    /// once, and the answer is to reload and decide, not to give up.
75    ///
76    /// Collapsing them made a caller unable to tell "try again from
77    /// what is stored now" from "this can never work".
78    #[error("conflict: {what} was changed by someone else first")]
79    Conflict { what: &'static str },
80
81    /// No candidate satisfied the structured output contract.
82    #[error("no valid proposal satisfied output contract `{contract_id}`")]
83    NoValidProposal { contract_id: String },
84}
made_core/error.rs

made_core/
error.rs
