core-lib 0.2.0

Rust library
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141

use chrono::{DateTime, Utc};
use serde::{Deserialize, Serialize};
use uuid::Uuid;

use crate::events::Error;

// Event
#[derive(Debug, Clone, PartialEq)]
pub struct Event {
    id: String,
    entity_id: String,
    topic: String,
    payload: Vec<u8>,
    timestamp: DateTime<Utc>,
}

impl Event {
    pub fn new(
        id: String,
        entity_id: String,
        topic: String,
        payload: Vec<u8>,
        timestamp: DateTime<Utc>,
    ) -> Result<Event, Error> {
        if id.is_empty() {
            return Err(Error::InvalidEvent);
        }

        if entity_id.is_empty() {
            return Err(Error::InvalidEvent);
        }

        if topic.is_empty() {
            return Err(Error::InvalidEvent);
        }

        if payload.is_empty() {
            return Err(Error::InvalidEvent);
        }

        Ok(Event {
            id,
            entity_id,
            topic,
            payload,
            timestamp,
        })
    }

    pub fn create<I, T, P>(entity_id: I, topic: T, payload: &P) -> Result<Event, Error>
    where
        I: Into<String>,
        T: Into<String>,
        P: Serialize,
    {
        let entity_id = entity_id.into();
        let topic = topic.into();

        let payload = serde_json::to_vec(payload).map_err(Error::SerializingPayload)?;

        Event::new(
            Uuid::new_v4().to_string(),
            entity_id,
            topic,
            payload,
            Utc::now(),
        )
    }

    pub fn id(&self) -> &str {
        &self.id
    }

    pub fn entity_id(&self) -> &str {
        &self.entity_id
    }

    pub fn topic(&self) -> &str {
        &self.topic
    }

    pub fn payload(&self) -> &[u8] {
        &self.payload
    }

    pub fn deserialize_payload<'a, T>(&'a self) -> Result<T, Error>
    where
        T: Deserialize<'a>,
    {
        serde_json::from_slice(&self.payload).map_err(Error::DeserializingPayload)
    }

    pub fn timestamp(&self) -> &DateTime<Utc> {
        &self.timestamp
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[derive(Debug, Serialize, Deserialize)]
    struct Data {
        msg: String,
    }

    #[test]
    fn create() {
        let res = Event::create(
            "entity#01",
            "topic.code",
            &Data {
                msg: "Hello World".to_string(),
            },
        );
        assert!(res.is_ok());

        let event = res.unwrap();
        assert_eq!(event.entity_id(), "entity#01");
        assert_eq!(event.topic(), "topic.code");
        assert!(event.payload().len() > 0);
    }

    #[test]
    fn payload_serialization_and_deserialization() {
        let event = Event::create(
            "entity#01",
            "topic.code",
            &Data {
                msg: "Hello World".to_string(),
            },
        )
        .unwrap();

        let res = event.deserialize_payload();
        assert!(res.is_ok());

        let data: Data = res.unwrap();
        assert_eq!(data.msg, "Hello World");
    }
}