Pagination

I hate math

gallery/views/image.py

@@ -1,6 +1,8 @@
 """
 Onlylegs - Image View
 """
+from math import ceil
+
 from flask import Blueprint, abort, render_template, url_for
 
 from sqlalchemy.orm import sessionmaker
@@ -55,5 +57,26 @@ def image(image_id):
         next_url = url_for('image.image', image_id=next_url[0])
     if prev_url:
         prev_url = url_for('image.image', image_id=prev_url[0])
+        
+    
+    # Yoink all the images in the database
+    total_images = (db_session.query(db.Posts.id)
+                              .order_by(db.Posts.id.desc())
+                              .all())
+    limit = 100
 
-    return render_template('image.html', image=image, next_url=next_url, prev_url=prev_url)
+    # If the number of items is less than the limit, no point of calculating the page
+    if len(total_images) <= limit:
+        return_page = 1
+    else:
+        # How many pages should there be
+        for i in range(ceil(len(total_images) / limit)):
+            # Slice the list of IDs into chunks of the limit
+            for j in total_images[i * limit:(i + 1) * limit]:
+                # Is our image in this chunk?
+                if image_id in j:
+                    return_page = i + 1
+                    break
+
+    return render_template('image.html', image=image, next_url=next_url,
+                           prev_url=prev_url, return_page=return_page)

gallery/views/index.py

@@ -1,6 +1,8 @@
 """
 Onlylegs Gallery - Index view
 """
+from math import ceil
+
 from flask import Blueprint, render_template, request
 from werkzeug.exceptions import abort
 
@@ -18,13 +20,30 @@ def index():
     """
     Home page of the website, shows the feed of the latest images
     """
-    images = db_session.query(db.Posts.filename,
-                              db.Posts.alt,
-                              db.Posts.colours,
-                              db.Posts.created_at,
-                              db.Posts.id).order_by(db.Posts.id.desc()).all()
-
+    # meme
     if request.args.get('coffee') == 'please':
         abort(418)
+    
+    # pagination, defaults to page 1 if no page is specified
+    page = request.args.get('page', default=1, type=int)
+    limit = 100
+    
+    # get the total number of images in the database
+    # calculate the total number of pages, and make sure the page number is valid
+    total_images = db_session.query(db.Posts.id).count()
+    pages = ceil(max(total_images, limit) / limit)
+    if page > pages:
+        abort(404, 'You have reached the far and beyond, ' +
+              'but you will not find your answers here.')
+    
+    # get the images for the current page
+    images = (db_session.query(db.Posts.filename, db.Posts.alt, db.Posts.colours,
+                               db.Posts.created_at, db.Posts.id)
+                        .order_by(db.Posts.id.desc())
+                        .offset((page - 1) * limit)
+                        .limit(limit)
+                        .all())
 
-    return render_template('index.html', images=images)
+    return render_template('index.html', images=images,
+                           total_images=total_images,
+                           pages=pages, page=page)