a3s_effect/
fact.rs

1use serde::{Deserialize, Serialize};
2use serde_json::Value;
3use sha2::{Digest, Sha256};
4
5use crate::error::ActorError;
6
7/// One immutable fact. `cause` is the transition key that wrote it, or `None`
8/// when a caller method appended it.
9#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
10pub struct Fact {
11    pub seq: u64,
12    #[serde(rename = "type")]
13    pub kind: String,
14    pub key: String,
15    pub cause: Option<String>,
16    pub payload: Value,
17}
18
19#[derive(Debug, Clone, PartialEq)]
20pub struct NewFact {
21    pub kind: String,
22    pub key: String,
23    pub payload: Value,
24}
25
26#[derive(Debug, Clone, PartialEq, Eq)]
27pub struct LogCut {
28    pub seq: u64,
29    pub digest: String,
30}
31
32#[derive(Debug, Deserialize)]
33#[serde(deny_unknown_fields)]
34struct FactDto {
35    seq: u64,
36    #[serde(rename = "type")]
37    kind: String,
38    key: String,
39    cause: Option<String>,
40    payload: Value,
41}
42
43pub fn parse_fact_json(value: &str) -> Result<Fact, ActorError> {
44    let dto: FactDto =
45        serde_json::from_str(value).map_err(|error| ActorError::Schema(error.to_string()))?;
46    if dto.kind.is_empty() || dto.key.is_empty() {
47        return Err(ActorError::Schema("type and key are required".into()));
48    }
49    Ok(Fact {
50        seq: dto.seq,
51        kind: dto.kind,
52        key: dto.key,
53        cause: dto.cause,
54        payload: dto.payload,
55    })
56}
57
58pub fn digest_facts(facts: &[Fact]) -> String {
59    let mut hasher = Sha256::new();
60    for fact in facts {
61        hasher.update(fact.seq.to_string());
62        hasher.update(fact.kind.as_bytes());
63        hasher.update(fact.key.as_bytes());
64        hasher.update(fact.cause.as_deref().unwrap_or(""));
65        hasher.update(fact.payload.to_string());
66        hasher.update([0xff]);
67    }
68    format!("{:x}", hasher.finalize())
69}
70
71pub fn cut_log(facts: &[Fact]) -> LogCut {
72    LogCut {
73        seq: facts.last().map(|fact| fact.seq).unwrap_or(0),
74        digest: digest_facts(facts),
75    }
76}
a3s_effect/fact.rs

a3s_effect/
fact.rs
