feat(blog::api) get_identifier.rs

backend/server/src/modules/blog/api/posts/get_identifier.rs

@@ -0,0 +1,130 @@
+use crate::utils::axum_response::{err_resp, succ_resp};
+
+use axum::{
+    extract::{Path, State},
+    http::StatusCode,
+    response::IntoResponse,
+};
+use chrono::NaiveDate;
+use futures::future::OptionFuture;
+use serde_json::Value;
+use sqlx::{FromRow, PgPool, query_as};
+use uuid::Uuid;
+
+const SELECT_POST_BY_UUID: &str = include_str!("get_post_by_uuid.sql");
+const SELECT_POST_BY_STR_ID: &str = include_str!("get_post_by_str_id.sql");
+const SELECT_POST_ADJACENT_IDS: &str = include_str!("get_post_adjacent_ids.sql");
+const SELECT_POST_WITH_ADJACENT_MODEL: &str = include_str!("get_post_with_adjacent_model.sql");
+
+#[derive(serde::Serialize, FromRow)]
+struct SelectedPost {
+    id: Uuid,
+    identifier: String,
+    title: String,
+    subtitle: String,
+    status: String,
+    date_created: NaiveDate,
+    date_updated: Option<NaiveDate>,
+    category: String,
+    tags: Vec<String>,
+    content: String,
+    metadata: Value,
+}
+
+#[derive(serde::Serialize, FromRow)]
+struct AdjacentPost {
+    id: Uuid,
+    identifier: String,
+    title: String,
+    subtitle: String,
+    date_created: NaiveDate,
+    category: String,
+    tags: Vec<String>,
+    header_img: Option<String>,
+}
+
+#[derive(FromRow, Debug)]
+struct AdjacentIds {
+    prev: Option<Uuid>,
+    next: Option<Uuid>,
+}
+
+#[derive(serde::Serialize, Default)]
+struct AdjacentPosts {
+    prev: Option<AdjacentPost>,
+    next: Option<AdjacentPost>,
+}
+
+#[derive(serde::Serialize)]
+struct ResponseModel {
+    post: SelectedPost,
+    adjacent: AdjacentPosts,
+}
+
+pub async fn handler(
+    State(db_connection): State<PgPool>,
+    Path(identifier): Path<String>,
+) -> impl IntoResponse {
+    let post = match if let Ok(id) = identifier.parse::<Uuid>() {
+        select_post_by_uuid(&db_connection, id).await
+    } else {
+        select_post_by_str_id(&db_connection, &identifier).await
+    } {
+        Ok(post) => post,
+        Err(e) => {
+            return match e {
+                sqlx::Error::RowNotFound => err_resp(StatusCode::NOT_FOUND, "no matching post"),
+                _ => err_resp(StatusCode::INTERNAL_SERVER_ERROR, &e.to_string()),
+            };
+        }
+    };
+
+    let adj_ids = query_as::<_, AdjacentIds>(SELECT_POST_ADJACENT_IDS)
+        .bind(post.id)
+        .fetch_one(&db_connection)
+        .await
+        .unwrap();
+    let adjacent_prev = OptionFuture::from(
+        adj_ids
+            .prev
+            .map(|id| select_post_with_adjacent_model(&db_connection, id)),
+    )
+    .await
+    .flatten();
+    let adjacent_next = OptionFuture::from(
+        adj_ids
+            .next
+            .map(|id| select_post_with_adjacent_model(&db_connection, id)),
+    )
+    .await
+    .flatten();
+    let adjacent = AdjacentPosts {
+        prev: adjacent_prev,
+        next: adjacent_next,
+    };
+
+    let response = ResponseModel { post, adjacent };
+    succ_resp(StatusCode::OK, serde_json::to_value(response).unwrap())
+}
+
+async fn select_post_by_uuid(db: &PgPool, id: Uuid) -> Result<SelectedPost, sqlx::Error> {
+    query_as::<_, SelectedPost>(SELECT_POST_BY_UUID)
+        .bind(id)
+        .fetch_one(db)
+        .await
+}
+
+async fn select_post_by_str_id(db: &PgPool, id: &str) -> Result<SelectedPost, sqlx::Error> {
+    query_as::<_, SelectedPost>(SELECT_POST_BY_STR_ID)
+        .bind(id)
+        .fetch_one(db)
+        .await
+}
+
+async fn select_post_with_adjacent_model(db: &PgPool, id: Uuid) -> Option<AdjacentPost> {
+    query_as(SELECT_POST_WITH_ADJACENT_MODEL)
+        .bind(id)
+        .fetch_optional(db)
+        .await
+        .unwrap()
+}