made_core/value_objects/outbox/
outbox_subject.rs

1use std::fmt;
2
3use serde::{Deserialize, Serialize};
4
5use crate::error::DomainError;
6
7const MAX_SUBJECT_LEN: usize = 256;
8
9/// Where an outbox message is destined once it is published.
10///
11/// Kept opaque to the engine: the domain decides that a message must go
12/// out and under what name, and the transport decides what that name
13/// means.
14#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Serialize, Deserialize)]
15#[serde(transparent)]
16pub struct OutboxSubject(String);
17
18impl OutboxSubject {
19    pub fn new(raw: impl Into<String>) -> Result<Self, DomainError> {
20        let raw = raw.into();
21        let trimmed = raw.trim();
22        if trimmed.is_empty() {
23            return Err(DomainError::EmptyField {
24                field: "outbox_subject",
25            });
26        }
27        if trimmed.len() > MAX_SUBJECT_LEN {
28            return Err(DomainError::FieldTooLong {
29                field: "outbox_subject",
30                actual: trimmed.len(),
31                max: MAX_SUBJECT_LEN,
32            });
33        }
34        if trimmed.chars().any(char::is_whitespace) {
35            return Err(DomainError::InvalidCharacters {
36                field: "outbox_subject",
37            });
38        }
39        Ok(Self(trimmed.to_owned()))
40    }
41
42    #[must_use]
43    pub fn as_str(&self) -> &str {
44        &self.0
45    }
46}
47
48impl fmt::Display for OutboxSubject {
49    fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
50        formatter.write_str(&self.0)
51    }
52}
53
54#[cfg(test)]
55mod tests {
56    use super::*;
57
58    #[test]
59    fn an_empty_or_spaced_subject_is_rejected() {
60        assert!(OutboxSubject::new("  ").is_err());
61        assert!(OutboxSubject::new("two words").is_err());
62    }
63
64    #[test]
65    fn a_dotted_subject_is_accepted_and_trimmed() {
66        let subject = OutboxSubject::new("  made.ceremony.completed  ").unwrap();
67
68        assert_eq!(subject.as_str(), "made.ceremony.completed");
69    }
70}
made_core/value_objects/outbox/outbox_subject.rs

made_core/value_objects/outbox/
outbox_subject.rs
