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
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160

use std::collections::HashMap;
use std::fmt::{Display, Formatter};
use chrono::{NaiveDateTime};
use reqwest::blocking::Client as HttpClient;
use reqwest::header::CONTENT_TYPE;
use serde::{Serialize};
use std::time::Duration;

extern crate serde_json;

const API_ENDPOINT: &str = "https://app.posthog.com/capture/";
const TIMEOUT: &Duration = &Duration::from_millis(800); // This should be specified by the user

pub fn client<C: Into<ClientOptions>>(options: C) -> Client {
    let client = HttpClient::builder().timeout(Some(TIMEOUT.clone())).build().unwrap(); // Unwrap here is as safe as `HttpClient::new`
    Client {
        options: options.into(),
        client,
    }
}

impl Display for Error {
    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
        match self {
            Error::Connection(msg) => write!(f, "Connection Error: {}", msg),
            Error::Serialization(msg) => write!(f, "Serialization Error: {}", msg)
        }
    }
}

impl std::error::Error for Error {

}

#[derive(Debug)]
pub enum Error {
    Connection(String),
    Serialization(String)
}

pub struct ClientOptions {
    api_endpoint: String,
    api_key: String,
}

impl From<&str> for ClientOptions {
    fn from(api_key: &str) -> Self {
        ClientOptions {
            api_endpoint: API_ENDPOINT.to_string(),
            api_key: api_key.to_string(),
        }
    }
}

pub struct Client {
    options: ClientOptions,
    client: HttpClient,
}

impl Client {
    pub fn capture(&self, event: Event) -> Result<(), Error> {
        let inner_event = InnerEvent::new(event, self.options.api_key.clone());
        let _res = self.client.post(self.options.api_endpoint.clone())
            .header(CONTENT_TYPE, "application/json")
            .body(serde_json::to_string(&inner_event).expect("unwrap here is safe"))
            .send()
            .map_err(|e| Error::Connection(e.to_string()))?;
        Ok(())
    }

    pub fn capture_batch(&self, events: Vec<Event>) -> Result<(), Error> {
        for event in events {
            self.capture(event)?;
        }
        Ok(())
    }
}

// This exists so that the client doesn't have to specify the API key over and over
#[derive(Serialize)]
struct InnerEvent {
    api_key: String,
    event: String,
    properties: Properties,
    timestamp: Option<NaiveDateTime>,
}

impl InnerEvent {
    fn new(event: Event, api_key: String) -> Self {
        Self {
            api_key,
            event: event.event,
            properties: event.properties,
            timestamp: event.timestamp,
        }
    }
}


#[derive(Serialize, Debug, PartialEq, Eq)]
pub struct Event {
    event: String,
    properties: Properties,
    timestamp: Option<NaiveDateTime>,
}

#[derive(Serialize, Debug, PartialEq, Eq)]
pub struct Properties {
    distinct_id: String,
    props: HashMap<String, serde_json::Value>,
}

impl Properties {
    fn new<S: Into<String>>(distinct_id: S) -> Self {
        Self {
            distinct_id: distinct_id.into(),
            props: Default::default()
        }
    }
}

impl Event {
    pub fn new<S: Into<String>>(event: S, distinct_id: S) -> Self {
        Self {
            event: event.into(),
            properties: Properties::new(distinct_id),
            timestamp: None
        }
    }

    /// Errors if `prop` fails to serialize
    pub fn insert_prop<K: Into<String>, P: Serialize>(&mut self, key: K, prop: P) -> Result<(), Error> {
        let as_json = serde_json::to_value(prop).map_err(|e| Error::Serialization(e.to_string()))?;
        let _ = self.properties.props.insert(key.into(), as_json);
        Ok(())
    }
}


#[cfg(test)]
pub mod tests {
    use super::*;
    use chrono::{Utc};

    #[test]
    fn get_client() {
        let client = crate::client(env!("POSTHOG_API_KEY"));

        let mut child_map = HashMap::new();
        child_map.insert("child_key1", "child_value1");


        let mut event = Event::new("test", "1234");
        event.insert_prop("key1", "value1").unwrap();
        event.insert_prop("key2", vec!["a", "b"]).unwrap();
        event.insert_prop("key3", child_map).unwrap();

        client.capture(event).unwrap();
    }
}