paginated authors

calibre-db/src/calibre.rs

@@ -34,7 +34,7 @@ impl Calibre {
         &self,
         limit: u64,
         cursor: Option<&str>,
-        sort_order: SortOrder,
+        sort_order: &SortOrder,
     ) -> Result<Vec<Author>, DataStoreError> {
         let conn = self.pool.get()?;
         Author::multiple(&conn, limit, cursor, sort_order)
@@ -80,6 +80,16 @@ impl Calibre {
         let conn = self.pool.get()?;
         Series::book_series(&conn, id)
     }
+
+    pub fn has_previous_authors(&self, author_sort: &str) -> Result<bool, DataStoreError> {
+        let conn = self.pool.get()?;
+        Author::has_previous_authors(&conn, author_sort)
+    }
+
+    pub fn has_more_authors(&self, author_sort: &str) -> Result<bool, DataStoreError> {
+        let conn = self.pool.get()?;
+        Author::has_more_authors(&conn, author_sort)
+    }
 }
 
 #[cfg(test)]
@@ -100,7 +110,7 @@ mod tests {
     #[test]
     fn authors() {
         let c = init_calibre();
-        let authors = c.authors(10, None, SortOrder::ASC).unwrap();
+        let authors = c.authors(10, None, &SortOrder::ASC).unwrap();
         assert_eq!(authors.len(), 3);
     }
 
@@ -114,24 +124,24 @@ mod tests {
     #[test]
     fn pagination() {
         let c = init_calibre();
-        let authors = c.authors(1, None, SortOrder::ASC).unwrap();
+        let authors = c.authors(1, None, &SortOrder::ASC).unwrap();
         assert_eq!(authors.len(), 1);
         assert_eq!(authors[0].name, "Kevin R. Grazier");
 
         let authors = c
-            .authors(1, Some(&authors[0].sort), SortOrder::ASC)
+            .authors(1, Some(&authors[0].sort), &SortOrder::ASC)
             .unwrap();
         assert_eq!(authors.len(), 1);
         assert_eq!(authors[0].name, "Terry Pratchett");
 
         let authors = c
-            .authors(1, Some(&authors[0].sort), SortOrder::ASC)
+            .authors(1, Some(&authors[0].sort), &SortOrder::ASC)
             .unwrap();
         assert_eq!(authors.len(), 1);
         assert_eq!(authors[0].name, "Edward Noyes Westcott");
 
         let authors = c
-            .authors(1, Some(&authors[0].sort), SortOrder::DESC)
+            .authors(1, Some(&authors[0].sort), &SortOrder::DESC)
             .unwrap();
         assert_eq!(authors.len(), 1);
         assert_eq!(authors[0].name, "Terry Pratchett");

calibre-db/src/data/author.rs

@@ -26,9 +26,9 @@ impl Author {
         conn: &Connection,
         limit: u64,
         cursor: Option<&str>,
-        sort_order: SortOrder,
+        sort_order: &SortOrder,
     ) -> Result<Vec<Self>, DataStoreError> {
-        let pagination = Pagination::new("sort", cursor, limit, sort_order);
+        let pagination = Pagination::new("sort", cursor, limit, *sort_order);
         pagination.paginate(
             conn,
             "SELECT id, name, sort FROM authors",
@@ -46,4 +46,25 @@ impl Author {
         let params = named_params! { ":id": id };
         Ok(stmt.query_row(params, Self::from_row)?)
     }
+
+    pub fn has_previous_authors(
+        conn: &Connection,
+        sort_name: &str,
+    ) -> Result<bool, DataStoreError> {
+        let mut stmt = conn
+            .prepare("SELECT Count(1) FROM authors WHERE sort < (:sort_name) ORDER BY sort DESC")?;
+        let params = named_params! { ":sort_name": sort_name };
+        let count: u64 = stmt.query_row(params, |x| x.get(0))?;
+
+        Ok(count > 0)
+    }
+
+    pub fn has_more_authors(conn: &Connection, sort_name: &str) -> Result<bool, DataStoreError> {
+        let mut stmt = conn
+            .prepare("SELECT Count(1) FROM authors WHERE sort > (:sort_name) ORDER BY sort ASC")?;
+        let params = named_params! { ":sort_name": sort_name };
+        let count: u64 = stmt.query_row(params, |x| x.get(0))?;
+
+        Ok(count > 0)
+    }
 }

calibre-db/src/data/pagination.rs

@@ -1,8 +1,9 @@
 use rusqlite::{Connection, Row, ToSql};
+use serde::{Deserialize, Serialize};
 
 use super::error::DataStoreError;
 
-#[derive(Debug, PartialEq)]
+#[derive(Debug, Copy, Clone, PartialEq, Deserialize, Serialize)]
 pub enum SortOrder {
     ASC,
     DESC,
@@ -53,10 +54,17 @@ impl<'a> Pagination<'a> {
         };
 
         let sort_col = self.sort_col;
+        // otherwise paginated statements with join will fail
+        let sort_col_wrapped = if let Some(index) = sort_col.find('.') {
+            let right_part = &sort_col[index..];
+            "t".to_owned() + right_part
+        } else {
+            sort_col.to_owned()
+        };
         let sort_order = &self.sort_order;
         // DANGER: vulnerable to SQL injection if statement or sort_col variable is influenced by user input
         let mut stmt = conn.prepare(&format!(
-            "{statement} {where_sql} {sort_col} {comparison} (:cursor) ORDER BY {sort_col} {sort_order:?} LIMIT (:limit)"
+            "SELECT * FROM ({statement} {where_sql} {sort_col} {comparison} (:cursor) ORDER BY {sort_col} {sort_order:?} LIMIT (:limit)) AS t ORDER BY {sort_col_wrapped} ASC"
         ))?;
         let params = [
             &[

rusty-library/src/handlers/authors.rs

@@ -1,10 +1,34 @@
 use std::sync::Arc;
 
-use poem::{handler, web::Data};
+use calibre_db::data::pagination::SortOrder;
+use poem::{
+    handler,
+    web::{Data, Html, Path},
+};
 
-use crate::app_state::AppState;
+use crate::{app_state::AppState, handlers::paginated};
 
 #[handler]
-pub async fn handler(state: Data<&Arc<AppState>>) -> Result<String, poem::Error> {
-    Ok("authors".to_string())
+pub async fn handler_init(state: Data<&Arc<AppState>>) -> Result<Html<String>, poem::Error> {
+    paginated::render(
+        "authors",
+        || state.calibre.authors(25, None, &SortOrder::ASC),
+        |author| author.sort.clone(),
+        |cursor| state.calibre.has_previous_authors(cursor),
+        |cursor| state.calibre.has_more_authors(cursor),
+    )
+}
+
+#[handler]
+pub async fn handler(
+    Path((cursor, sort_order)): Path<(String, SortOrder)>,
+    state: Data<&Arc<AppState>>,
+) -> Result<Html<String>, poem::Error> {
+    paginated::render(
+        "authors",
+        || state.calibre.authors(25, Some(&cursor), &sort_order),
+        |author| author.sort.clone(),
+        |cursor| state.calibre.has_previous_authors(cursor),
+        |cursor| state.calibre.has_more_authors(cursor),
+    )
 }

rusty-library/src/handlers/paginated.rs

@@ -0,0 +1,46 @@
+use calibre_db::data::error::DataStoreError;
+use poem::{error::InternalServerError, web::Html};
+use serde::Serialize;
+use tera::Context;
+
+use crate::templates::TEMPLATES;
+
+use super::error::SqliteError;
+
+pub fn render<T: Serialize, F, S, P, M>(
+    template: &str,
+    fetcher: F,
+    sort_field: S,
+    has_previous: P,
+    has_more: M,
+) -> Result<Html<String>, poem::Error>
+where
+    F: Fn() -> Result<Vec<T>, DataStoreError>,
+    S: Fn(&T) -> String,
+    P: Fn(&str) -> Result<bool, DataStoreError>,
+    M: Fn(&str) -> Result<bool, DataStoreError>,
+{
+    let items = fetcher().map_err(SqliteError)?;
+
+    let mut context = Context::new();
+
+    // fails already in the sql query if there is nothing returned
+    let first_item = items.first().unwrap();
+    let last_item = items.last().unwrap();
+
+    let (backward_cursor, forward_cursor) = (sort_field(first_item), sort_field(last_item));
+
+    let has_previous = has_previous(&backward_cursor).map_err(SqliteError)?;
+    let has_more = has_more(&forward_cursor).map_err(SqliteError)?;
+
+    context.insert("has_previous", &has_previous);
+    context.insert("has_more", &has_more);
+    context.insert("backward_cursor", &backward_cursor);
+    context.insert("forward_cursor", &forward_cursor);
+    context.insert("nav", template);
+    context.insert(template, &items);
+    TEMPLATES
+        .render(template, &context)
+        .map_err(InternalServerError)
+        .map(Html)
+}

rusty-library/src/handlers/recents.rs

@@ -13,13 +13,15 @@ use crate::{
 
 #[handler]
 pub async fn handler(state: Data<&Arc<AppState>>) -> Result<Html<String>, poem::Error> {
-    let recent_books = state.calibre.recent_books(50).map_err(SqliteError)?;
+    let recent_books = state.calibre.recent_books(25).map_err(SqliteError)?;
     let recent_books = recent_books
         .iter()
         .filter_map(|x| Book::full_book(x, &state))
         .collect::<Vec<Book>>();
 
     let mut context = Context::new();
+    context.insert("title", "Recent Books");
+    context.insert("nav", "recent");
     context.insert("books", &recent_books);
     TEMPLATES
         .render("recents", &context)

rusty-library/src/main.rs

@@ -23,6 +23,7 @@ mod handlers {
     pub mod cover;
     pub mod download;
     pub mod error;
+    pub mod paginated;
     pub mod recents;
     pub mod series;
 }
@@ -48,7 +49,11 @@ async fn main() -> Result<(), std::io::Error> {
     let app = Route::new()
         .at("/", get(handlers::recents::handler))
         .at("/books", get(handlers::books::handler))
-        .at("/authors", get(handlers::authors::handler))
+        .at("/authors", get(handlers::authors::handler_init))
+        .at(
+            "/authors/:cursor/:sort_order",
+            get(handlers::authors::handler),
+        )
         .at("/series", get(handlers::series::handler))
         .at("/cover/:id", get(handlers::cover::handler))
         .at("/book/:id/:format", get(handlers::download::handler))

rusty-library/src/templates.rs

@@ -6,6 +6,7 @@ pub static TEMPLATES: Lazy<Tera> = Lazy::new(|| {
     tera.add_raw_templates(vec![
         ("base", include_str!("../templates/base.html")),
         ("book_card", include_str!("../templates/book_card.html")),
+        ("authors", include_str!("../templates/authors.html")),
         ("recents", include_str!("../templates/recents.html")),
     ])
     .expect("failed to parse tera templates");

rusty-library/static/style.css

@@ -3,6 +3,21 @@
    overflow: scroll;
    text-overflow: ellipsis;
 }
+header.fixed {
+  position: sticky;
+  top: 0;
+  z-index: 1000;
+  background: var(--pico-background-color)
+}
+
+nav ul li {
+  padding-top: 0rem;
+  padding-bottom: 0.25rem;
+}
+
+.nav-active {
+  border-bottom: solid var(--pico-primary-underline);
+}
 
 .book-card hgroup {
   margin-bottom: 0;

rusty-library/templates/authors.html

@@ -0,0 +1,19 @@
+{% extends "base" %}
+{% block title %}
+{% if has_previous %}
+<a href="/authors/{{ backward_cursor }}/DESC">← back</a> 
+{% endif %} 
+{% if has_previous and has_more %}|{% endif%}
+
+{% if has_more %}
+<a href="/authors/{{ forward_cursor }}/ASC">more →</a>
+{% endif %}
+{% endblock title %}
+
+{% block content %}
+    <div class="grid-container">
+    {% for author in authors %}
+      <article>{{ author.name }}</article>
+    {% endfor %}
+    </div>
+{% endblock content %}

rusty-library/templates/base.html

@@ -9,18 +9,20 @@
     <title>Rusty Library</title>
   </head>
   <body>
-    <main class="container">
+    <header class="container fixed">
       <nav>
         <ul>
-          <li><strong>Library</strong></li>
+          <li>{% block title %}<strong>{{ title }}</strong>{% endblock title %}</li>
         </ul>
         <ul>
-          <li><a href="/">Recent</a></li>
-          <li><a href="/authors">Authors</a></li>
-          <li><a href="/books">Books</a></li>
-          <li><a href="/series">Series</a></li>
+          <li {% if nav == "recent" %}class = "nav-active"{% endif %}><a href="/">Recent</a></li>
+          <li {% if nav == "authors" %}class = "nav-active"{% endif %}><a href="/authors">Authors</a></li>
+          <li {% if nav == "books" %}class = "nav-active"{% endif %}><a href="/books">Books</a></li>
+          <li {% if nav == "series" %}class = "nav-active"{% endif %}><a href="/series">Series</a></li>
         </ul>
       </nav>
+    </header>
+    <main class="container">
       {% block content %}{% endblock content %}
     </main>
   </body>

rusty-library/templates/recents.html

@@ -1,6 +1,5 @@
 {% extends "base" %}
 {% block content %}
-    <h1>Recent Books</h1>
     <div class="grid-container">
     {% for book in books %}
     {% include "book_card" %}