Migrated project into separate directories

weather-service/src/metars/model.rs

@@ -0,0 +1,162 @@
+use crate::error_handler::CustomError;
+use crate::schema::metars;
+use log::warn;
+use std::io::BufRead;
+use quick_xml::{Reader, events::{Event, BytesStart}, Writer, de::Deserializer};
+use serde::{Deserialize, Serialize};
+
+#[derive(Serialize, Deserialize)]
+pub struct QualityControlFlags {
+    pub auto: Option<bool>,
+    pub auto_station: Option<bool>
+}
+
+#[derive(Serialize, Deserialize, AsChangeset, Insertable)]
+#[table_name = "metars"]
+pub struct Metar {
+    pub icao: String,
+    pub raw_text: String,
+    pub station_id: String,
+    pub observation_time: String,
+    pub latitude: f64,
+    pub longitude: f64,
+    pub temp_c: f64,
+    pub dewpoint_c: f64,
+    pub wind_dir_degrees: i32,
+    pub wind_speed_kt: i32,
+    pub visibility_statute_mi: String,
+    pub altim_in_hg: f64,
+    pub sea_level_pressure_mb: Option<f64>,
+    // pub quality_control_flags: Option<QualityControlFlags>,
+    pub wx_string: Option<String>,
+    // pub sky_con dition: Option<Vec<String>>, // TODO work on attributes
+    pub flight_category: String,
+    pub three_hr_pressure_tendency_mb: Option<f64>,
+    pub metar_type: String,
+    #[serde(rename = "maxT_c")]
+    pub max_t_c: Option<f64>,
+    #[serde(rename = "minT_c")]
+    pub min_t_c: Option<f64>,
+    pub precip_in: Option<f64>,
+    pub elevation_m: i32
+}
+
+#[derive(Serialize, Deserialize, Queryable)]
+pub struct Metars {
+    // pub id: i32,
+    // pub icao: String,
+    pub raw_text: String,
+    pub station_id: String,
+    pub observation_time: String,
+    pub latitude: f64,
+    pub longitude: f64,
+    pub temp_c: f64,
+    pub dewpoint_c: f64,
+    pub wind_dir_degrees: i32,
+    pub wind_speed_kt: i32,
+    pub visibility_statute_mi: String,
+    pub altim_in_hg: f64,
+    pub sea_level_pressure_mb: Option<f64>,
+    pub quality_control_flags: Option<QualityControlFlags>,
+    pub wx_string: Option<String>,
+    // pub sky_condition: Option<Vec<String>>, // TODO work on attributes
+    pub flight_category: String,
+    pub three_hr_pressure_tendency_mb: Option<f64>,
+    pub metar_type: String,
+    #[serde(rename = "maxT_c")]
+    pub max_t_c: Option<f64>,
+    #[serde(rename = "minT_c")]
+    pub min_t_c: Option<f64>,
+    pub precip_in: Option<f64>,
+    pub elevation_m: i32
+}
+
+impl Metars {
+    pub async fn get_all(icaos: String) -> Result<Vec<Self>, CustomError> {
+        // let station_string = station_icaos.join(",");
+        let url = format!("https://beta.aviationweather.gov/cgi-bin/data/metar.php?ids={}&format=xml", icaos);
+        let metars: Vec<Metars> = match reqwest::get(url).await {
+            Ok(r) => match r.text().await {
+                Ok(r) => {
+                    match Metars::parse(r) {
+                        Ok(m) => m,
+                        Err(err) => {
+                            warn!("{}", err);
+                            vec![]
+                        }
+                    }
+                },
+                Err(err) => {
+                    warn!("Unable to parse METAR request: {}", err);
+                    vec![]
+                }
+            },
+            Err(err) => {
+                warn!("Unable to get METAR request: {}", err);
+                vec![]
+            }
+        };
+        Ok(metars)
+    }
+
+    pub fn parse(input: String) -> Result<Vec<Self>, CustomError> {
+        if input.is_empty() {
+            return Err(CustomError::new(500, "Input is empty".to_string()))
+        }
+
+        let mut reader = Reader::from_str(&input);
+        let mut buf = Vec::new();
+        let mut junk_buf: Vec<u8> = Vec::new();
+        let mut metars: Vec<Self> = vec![];
+
+        loop {
+            match reader.read_event_into(&mut buf) {
+                Err(e) => panic!("Error at position: {}: {:?}", reader.buffer_position(), e),
+                Ok(Event::Eof) => break,
+                Ok(Event::Start(e)) => {
+                    match e.name().as_ref() {
+                        b"METAR" => {
+                            let metar_bytes = Metars::read_to_end_into_buffer(&mut reader, &e, &mut junk_buf).unwrap();
+                            let str = std::str::from_utf8(&metar_bytes).unwrap();
+                            let mut deserializer = Deserializer::from_str(str);
+                            let metar = Metars::deserialize(&mut deserializer).unwrap();
+                            metars.push(metar);
+                        },
+                        _ => ()
+                    }
+                },
+                _ => ()
+            }
+        }
+
+        return Ok(metars)
+    }
+
+    // https://capnfabs.net/posts/parsing-huge-xml-quickxml-rust-serde/
+    pub fn read_to_end_into_buffer<R: BufRead>(reader: &mut Reader<R>, start_tag: &BytesStart, junk_buf: &mut Vec<u8>) -> Result<Vec<u8>, quick_xml::Error> {
+        let mut depth = 0;
+        let mut output_buf: Vec<u8> = Vec::new();
+        let mut w = Writer::new(&mut output_buf);
+        let tag_name = start_tag.name();
+        w.write_event(Event::Start(start_tag.clone()))?;
+        loop {
+            junk_buf.clear();
+            let event = reader.read_event_into(junk_buf)?;
+            w.write_event(&event)?;
+      
+            match event {
+                Event::Start(e) if e.name() == tag_name => depth += 1,
+                Event::End(e) if e.name() == tag_name => {
+                    if depth == 0 {
+                        return Ok(output_buf);
+                    }
+                    depth -= 1;
+                }
+                Event::Eof => {
+                    panic!("EOF")
+                }
+                _ => {}
+            }
+        }
+    }
+}