Add metric query endpoint

metrix/src/main.rs

@@ -21,13 +21,16 @@ use lib::establish_connection;
 use schema::metrics;
 use models::*;
 use rocket_contrib::json::Json;
+use rocket::http::RawStr;
+use chrono::naive::NaiveDateTime;
+use diesel::sql_query;
+
 
 #[get("/")]
 fn ping() -> &'static str {
     "pong"
 }
 
-
 #[post("/", data = "<metric_body>")]
 fn create_metric_route(metric_body: Json<NewMetric>) -> Json<Metric> {
     let new_metric: NewMetric = metric_body.into_inner();
@@ -41,6 +44,73 @@ fn create_metric_route(metric_body: Json<NewMetric>) -> Json<Metric> {
     Json(result)
 }
 
+#[get("/?<offset>&<start_datetime>&<end_datetime>")]
+fn query_metric_route(
+    offset: Option<&RawStr>,
+    start_datetime: Option<&RawStr>,
+    end_datetime: Option<&RawStr>,
+) -> Json<Vec<Metric>> {
+    let db_conn = establish_connection();
+    let mut filter_clause = String::from("WHERE 1=1");
+
+    if offset.is_some() {
+        let result = offset.unwrap().url_decode();
+        // https://api.rocket.rs/v0.3/rocket/http/struct.RawStr.html
+        if result.is_ok() {
+            let metric_id_str: String = result.ok().unwrap();
+            filter_clause.insert_str(
+                filter_clause.len(),
+                &format!(" AND id > {}", metric_id_str).to_string()
+            );
+        }
+    }
+
+    if start_datetime.is_some() {
+        let result = start_datetime.unwrap().url_decode();
+        if result.is_ok() {
+            let created_at_start = result.ok().unwrap();
+            let created_at_start_parsed = NaiveDateTime::parse_from_str(
+                &created_at_start,
+                &"%Y-%m-%dT%H:%M:%S".to_string() // "2014-5-17T12:34:56"
+            );
+
+            if created_at_start_parsed.is_ok() {
+                filter_clause.insert_str(
+                    filter_clause.len(),
+                    &format!(" AND created_at >= '{}'", created_at_start).to_string()
+                );
+            }
+        }
+    }
+
+    if end_datetime.is_some() {
+        let result = end_datetime.unwrap().url_decode();
+        if result.is_ok() {
+            let created_at_end = result.ok().unwrap();
+            let created_at_end_parsed = NaiveDateTime::parse_from_str(
+                &created_at_end,
+                &"%Y-%m-%dT%H:%M:%S".to_string() // "2014-5-17T12:34:56"
+            );
+
+            if created_at_end_parsed.is_ok() {
+                filter_clause.insert_str(
+                    filter_clause.len(),
+                    &format!(" AND created_at <= '{}'", created_at_end).to_string()
+                );
+            }
+        }
+    }
+
+    println!("### QUERY: SELECT * FROM metrics {};", filter_clause);
+
+    let query_string = format!("SELECT * FROM metrics {} ORDER BY id LIMIT 10", filter_clause);
+    let results = sql_query(query_string)
+        .load(&db_conn)
+        .expect("Error loading metrics");
+
+    Json(results)
+}
+
 fn main() {
     println!("### Enter the Metrix ###");
     let db_conn = establish_connection();
@@ -51,6 +121,6 @@ fn main() {
 
     rocket::ignite()
         .mount("/ping", routes![ping])
-        .mount("/metrics", routes![create_metric_route])
+        .mount("/metrics", routes![create_metric_route, query_metric_route])
         .launch();
 }

metrix/src/models.rs

@@ -2,9 +2,8 @@ use super::schema::metrics;
 use serde_json;
 use chrono::naive::NaiveDateTime;
 
-#[derive(Serialize, Deserialize, Queryable)]
-// #[table_name="metrics"] -- idk why it throws compile error
-// "error: cannot find attribute `table_name` in this scope" ...
+#[derive(Serialize, Deserialize, Queryable, QueryableByName)]
+#[table_name="metrics"]
 pub struct Metric {
     pub id: i32,
     pub metric_name: String,