Basic endpoint to get weather for a location

.gitignore

@@ -1 +1,2 @@
 /target
+.env

Cargo.toml

@@ -7,3 +7,8 @@ edition = "2018"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+dotenv = "0.15.0"
+reqwest = { version = "0.10.8", features = ["json"] }
+rocket = { git = "https://github.com/SergioBenitez/Rocket", default-features = false }
+rocket_contrib = { git = "https://github.com/SergioBenitez/Rocket" }
+serde = { version = "1.0", features = ["derive"] }

src/main.rs

@@ -1,3 +1,19 @@
-fn main() {
-    println!("Hello, world!");
+#[macro_use]
+extern crate rocket;
+
+use dotenv::dotenv;
+
+mod weather;
+
+#[get("/weather/<loc>")]
+async fn get_weather(loc: String) -> Result<String, String> {
+    let sum = weather::get_summary(&loc).await?;
+    Ok(format!("The weather in {} is: {:?}", loc, sum))
+}
+
+#[rocket::launch]
+fn rocket() -> rocket::Rocket {
+    dotenv().ok();
+
+    rocket::ignite().mount("/", routes![get_weather])
 }

src/weather.rs

@@ -0,0 +1,70 @@
+use crate::rocket::futures::TryFutureExt;
+use serde::Deserialize;
+use std::env;
+
+#[derive(Debug, Deserialize)]
+struct APIResponseWeather {
+    main: String,
+    description: String,
+}
+
+#[derive(Debug, Deserialize)]
+struct APIResponseMain {
+    temp: f32,
+    feels_like: f32,
+    humidity: u32,
+    pressure: u32,
+}
+
+#[derive(Debug, Deserialize)]
+struct APIResponse {
+    weather: Vec<APIResponseWeather>,
+    main: APIResponseMain,
+}
+
+#[derive(Debug)]
+pub enum WeatherSummary {
+    Clear(i32),
+    Drizzle(i32),
+    Rain(i32),
+    Snow(i32),
+    Cloudy(i32),
+    Thunderstorm(i32),
+    Other(i32, String),
+}
+
+impl From<APIResponse> for WeatherSummary {
+    fn from(resp: APIResponse) -> Self {
+        let temp = resp.main.temp as i32;
+        match resp.weather[0].main.as_ref() {
+            "Thunderstorm" => Self::Thunderstorm(temp),
+            "Drizzle" => Self::Drizzle(temp),
+            "Rain" => Self::Rain(temp),
+            "Snow" => Self::Snow(temp),
+            "Clear" => Self::Clear(temp),
+            "Clouds" => Self::Cloudy(temp),
+            _ => Self::Other(temp, resp.weather[0].description.clone()),
+        }
+    }
+}
+
+pub async fn get_summary(loc: &str) -> Result<WeatherSummary, String> {
+    let api_key =
+        env::var("OPEN_WEATHERMAP_API_KEY").expect("could not load OPEN_WEATHERMAP_API_KEY");
+
+    let url = format!(
+        "https://api.openweathermap.org/data/2.5/weather?q={}&appid={}&units=metric",
+        loc, api_key
+    );
+
+    println!("Got URL: {}", &url);
+
+    let body = reqwest::get(&url)
+        .map_err(|e| e.to_string())
+        .await?
+        .json::<APIResponse>()
+        .map_err(|e| e.to_string())
+        .await?;
+
+    Ok(body.into())
+}