statsig_rust/sdk_event_emitter/
event_emitter.rs

1use crate::{
2    log_e,
3    sdk_event_emitter::{SdkEvent, SdkEventCode},
4    statsig_types::{DynamicConfig, Experiment, Layer},
5    Statsig,
6};
7use dashmap::DashMap;
8use std::{borrow::Cow, ops::Deref};
9
10const TAG: &str = "SdkEventEmitter";
11
12struct Listener {
13    sub_id_value: String,
14    callback: Box<dyn Fn(SdkEvent) + Send + Sync>,
15}
16
17#[derive(Clone)]
18pub struct SubscriptionID {
19    value: String,
20    event: String,
21}
22
23impl SubscriptionID {
24    pub fn new(event: &str) -> Self {
25        Self {
26            value: uuid::Uuid::new_v4().to_string(),
27            event: event.to_string(),
28        }
29    }
30
31    pub fn error() -> Self {
32        Self {
33            value: "ERROR".to_string(),
34            event: "ERROR".to_string(),
35        }
36    }
37
38    pub fn decode(s: &str) -> Option<Self> {
39        let parts: Vec<&str> = s.split('@').collect();
40        if parts.len() != 2 {
41            return None;
42        }
43
44        Some(Self {
45            value: parts[0].to_string(),
46            event: parts[1].to_string(),
47        })
48    }
49
50    pub fn encode(self) -> String {
51        let mut encoded = self.value;
52        encoded.push('@');
53        encoded.push_str(&self.event);
54        encoded
55    }
56}
57
58#[derive(Default)]
59pub struct SdkEventEmitter {
60    listeners: DashMap<u8, Vec<Listener>>,
61}
62
63impl SdkEventEmitter {
64    pub fn subscribe<F>(&self, event: &str, callback: F) -> SubscriptionID
65    where
66        F: Fn(SdkEvent) + Send + Sync + 'static,
67    {
68        let code = SdkEventCode::from_name(event).as_raw();
69        if code == 0 {
70            log_e!(TAG, "Invalid event name: {}", event);
71            return SubscriptionID::error();
72        }
73
74        let sub_id = SubscriptionID::new(event);
75
76        self.listeners.entry(code).or_default().push(Listener {
77            sub_id_value: sub_id.value.clone(),
78            callback: Box::new(callback),
79        });
80
81        sub_id
82    }
83
84    pub fn unsubscribe(&self, event: &str) {
85        let code = SdkEventCode::from_name(event).as_raw();
86        self.listeners.remove(&code);
87    }
88
89    pub fn unsubscribe_by_id(&self, subscription_id: &SubscriptionID) {
90        let code = SdkEventCode::from_name(&subscription_id.event).as_raw();
91        let mut listeners = match self.listeners.get_mut(&code) {
92            Some(listeners) => listeners,
93            None => return,
94        };
95
96        listeners.retain(|listener| listener.sub_id_value != subscription_id.value);
97    }
98
99    pub fn unsubscribe_all(&self) {
100        self.listeners.clear();
101    }
102
103    pub(crate) fn emit(&self, event: SdkEvent) {
104        let all_code = SdkEventCode::from_name(SdkEvent::ALL).as_raw();
105        self.emit_to_listeners(&event, self.listeners.get(&all_code).as_deref());
106
107        let event_code = event.get_code().as_raw();
108        self.emit_to_listeners(&event, self.listeners.get(&event_code).as_deref());
109    }
110
111    fn emit_to_listeners(&self, event: &SdkEvent, listeners: Option<&Vec<Listener>>) {
112        let listeners = match listeners {
113            Some(listeners) => listeners,
114            None => return,
115        };
116
117        listeners
118            .iter()
119            .for_each(|listener| (listener.callback)(event.clone()));
120    }
121}
122
123impl Deref for Statsig {
124    type Target = SdkEventEmitter;
125
126    fn deref(&self) -> &Self::Target {
127        &self.event_emitter
128    }
129}
130
131impl Statsig {
132    pub(crate) fn emit_gate_evaluated(
133        &self,
134        gate_name: &str,
135        rule_id: &str,
136        value: bool,
137        reason: &str,
138    ) {
139        self.emit(SdkEvent::GateEvaluated {
140            gate_name: gate_name.into(),
141            rule_id: rule_id.into(),
142            value,
143            reason: reason.into(),
144        });
145    }
146
147    pub(crate) fn emit_dynamic_config_evaluated(&self, config: &DynamicConfig) {
148        self.emit(SdkEvent::DynamicConfigEvaluated {
149            dynamic_config: Cow::Borrowed(config),
150        });
151    }
152
153    pub(crate) fn emit_experiment_evaluated(&self, experiment: &Experiment) {
154        self.emit(SdkEvent::ExperimentEvaluated {
155            experiment: Cow::Borrowed(experiment),
156        });
157    }
158
159    pub(crate) fn emit_layer_evaluated(&self, layer: &Layer) {
160        self.emit(SdkEvent::LayerEvaluated {
161            layer: Cow::Borrowed(layer),
162        });
163    }
164}
statsig_rust/sdk_event_emitter/event_emitter.rs

statsig_rust/sdk_event_emitter/
event_emitter.rs
