support random question fetching

backend/src/api.rs

@@ -10,6 +10,8 @@ const DEFAULT_PAGE: i32 = 0;
 const DEFAULT_PAGE_SIZE: i32 = 10;
 
 /// Fetches a single question using a provided id. First we fetch the question, then the questions tags, then build that into a response DTO
+/// If the id is 0 we fetch a random question. We exploit the fact that serial keys in postgres start from id=1 and not 0
+/// This would be poor practice for a public facing API, but saves us here from writing another similar API route -- Good enough
 /// # Parameters
 /// `id`: Path parmater Id of the question to lookup
 /// # Returns
@@ -19,8 +21,13 @@ pub async fn read_question(
     State(store): State<Arc<RwLock<Store>>>,
     Path(id): Path<u8>,
 ) -> Response {
-    //First, fetch the question
+    //First, fetch the question either by id or random if 0
-    let question_result = store.read().await.fetch_one_question_by_id(id).await;
+    let question_result: Option<question::Question> = if id == 0 {
+        store.read().await.fetch_one_random_question().await
+    } else {
+        store.read().await.fetch_one_question_by_id(id).await
+    };
+
     match question_result {
         Some(question) => {
             //Then fetch the tags for this question, if there are any

backend/src/pg_store.rs

@@ -324,6 +324,25 @@ impl Store {
         }
     }
 
+    // Fetch one random question, but do not worry about joining the tags
+    pub async fn fetch_one_random_question(&self) -> Option<Question> {
+        let row_result =
+            sqlx::query("SELECT id,title,content FROM questions ORDER BY RANDOM() LIMIT 1")
+                .fetch_one(&self.connection)
+                .await;
+        match row_result {
+            Ok(pg_row) => Some(Question::new(
+                Store::id_to_u8(&pg_row, "id"),
+                pg_row.get("title"),
+                pg_row.get("content"),
+            )),
+            Err(e) => {
+                println!("{}", e);
+                None
+            }
+        }
+    }
+
     // Fetch many questions - do not worry about joining the tags
     pub async fn fetch_many_questions(&self, start: i32, size: i32) -> Option<Vec<Question>> {
         let rows_result: Result<Vec<PgRow>, sqlx::Error> =

frontend/src/question.rs

@@ -12,7 +12,7 @@ pub struct QuestionStruct {
 impl QuestionStruct {
     pub async fn get_question(key: Option<String>) -> Msg {
         let request = match &key {
-            None => "http://localhost:3000/api/v1/question/2".to_string(),
+            None => "http://localhost:3000/api/v1/question/0".to_string(), // on the backend, 0 = random
             Some(ref key) => format!("http://localhost:3000/api/v1/question/{}", key,),
         };
         let response = http::Request::get(&request).send().await;