From 78399a3474d23289d7e4872e4f5a6d1ebf7eb13e Mon Sep 17 00:00:00 2001
From: Cadence Ember <cadence@disroot.org>
Date: Thu, 8 Sep 2022 00:16:24 +1200
Subject: [PATCH] Add strict_proxy option to proxy links to images

Default true.
---
 src/config.rkt    |  3 ++-
 src/page-wiki.rkt | 35 +++++++++++++++++++++++++++--------
 2 files changed, 29 insertions(+), 9 deletions(-)

diff --git a/src/config.rkt b/src/config.rkt
index 38433f9..4dc133e 100644
--- a/src/config.rkt
+++ b/src/config.rkt
@@ -20,7 +20,8 @@
     (canonical_origin . "")
     (debug . "false")
     (instance_is_official . "false") ; please don't turn this on, or you will make me very upset
-    (port . "10416")))
+    (port . "10416")
+    (strict_proxy . "true")))
 
 (define config
   (make-hasheq
diff --git a/src/page-wiki.rkt b/src/page-wiki.rkt
index f09900f..c770abc 100644
--- a/src/page-wiki.rkt
+++ b/src/page-wiki.rkt
@@ -30,9 +30,9 @@
            (aside (@ (role "region") (class "portable-infobox pi-theme-wikia pi-layout-default"))
                   (h2 (@ (class "pi-item pi-title") (data-source "title"))
                       "Infobox Title")
-                  (figure (@ (class "pi-item pi-image") (data-sourec "image"))
-                          (a (@ (href "https://static.wiki.nocookie.net/nice-image.png") (class "image image-thumbnail") (title ""))
-                             (img (@ (src "https://static.wiki.nocookie.net/nice-image-thumbnail.png") (class "pi-image-thumbnail")))))
+                  (figure (@ (class "pi-item pi-image") (data-source "image"))
+                          (a (@ (href "https://static.wikia.nocookie.net/nice-image.png") (class "image image-thumbnail") (title ""))
+                             (img (@ (src "https://static.wikia.nocookie.net/nice-image-thumbnail.png") (class "pi-image-thumbnail")))))
                   (div (@ (class "pi-item pi-data") (data-source "description"))
                        (h3 (@ (class "pi-data-label"))
                            "Description")
@@ -64,7 +64,7 @@
   (check-equal? (preprocess-html-wiki "<figure class=\"thumb tright\" style=\"width: 150px\"><a class=\"image\"><img></a><noscript><a><img></a></noscript><figcaption class=\"thumbcaption\"> 	<p class=\"caption\">Caption text.</p></figcaption></figure>")
                 "<figure class=\"thumb tright\" style=\"width: 150px\"><a class=\"image\"><img></a><noscript><a><img></a></noscript><figcaption class=\"thumbcaption\"><span class=\"caption\">Caption text.</span></figcaption></figure>"))
 
-(define (update-tree-wiki tree wikiname)
+(define (update-tree-wiki tree wikiname #:strict-proxy? strict-proxy?)
   (update-tree
    (λ (element element-type attributes children)
      ;; replace whole element?
@@ -142,7 +142,7 @@
                 (curry u
                        (λ (v) (and (eq? element-type 'a)
                                    (has-class? "image" v)))
-                       (λ (v) (dict-update attributes 'rel (λ (s)
+                       (λ (v) (dict-update v 'rel (λ (s)
                                                              (list (string-append (car s) " noreferrer")))
                                            '(""))))
                 ; proxy images from inline styles
@@ -154,6 +154,13 @@
                                             "url("
                                             (u-proxy-url url)
                                             ")")))))
+                ; and also their links, if strict-proxy is set
+                (curry u
+                       (λ (v)
+                         (and strict-proxy?
+                              (eq? element-type 'a)
+                              (has-class? "image-thumbnail" v)))
+                       (λ (v) (attribute-maybe-update 'href u-proxy-url v)))
                 ; proxy images from src attributes
                 (curry attribute-maybe-update 'src u-proxy-url)
                 ; don't lazyload images
@@ -176,7 +183,7 @@
                children))]))
    tree))
 (module+ test
-  (define transformed (update-tree-wiki wiki-document "test"))
+  (define transformed (update-tree-wiki wiki-document "test" #:strict-proxy? #t))
   ; check that wikilinks are changed to be local
   (check-equal? (get-attribute 'href (bits->attributes
                                       ((query-selector
@@ -201,7 +208,19 @@
   (check-equal? (let* ([alternative ((query-selector (λ (t a c) (has-class? "iframe-alternative" a)) transformed))]
                        [link ((query-selector (λ (t a c) (eq? t 'a)) alternative))])
                   (get-attribute 'href (bits->attributes link)))
-                "https://example.com/iframe-src"))
+                "https://example.com/iframe-src")
+  ; check that images are proxied
+  (check-equal? (get-attribute 'src (bits->attributes
+                                     ((query-selector
+                                       (λ (t a c) (eq? t 'img))
+                                       transformed))))
+                "/proxy?dest=https%3A%2F%2Fstatic.wikia.nocookie.net%2Fnice-image-thumbnail.png")
+  ; check that links to images are proxied
+  (check-equal? (get-attribute 'href (bits->attributes
+                                      ((query-selector
+                                        (λ (t a c) (and (eq? t 'a) (has-class? "image-thumbnail" a)))
+                                        transformed))))
+                "/proxy?dest=https%3A%2F%2Fstatic.wikia.nocookie.net%2Fnice-image.png"))
 
 (define (page-wiki req)
   (define wikiname (path/param-path (first (url-path (request-uri req)))))
@@ -230,7 +249,7 @@
            (next-dispatcher)
            (response-handler
             (define body
-              (generate-wiki-page source-url wikiname title (update-tree-wiki page wikiname)))
+              (generate-wiki-page source-url wikiname title (update-tree-wiki page wikiname #:strict-proxy? (config-true? 'strict_proxy))))
             (define redirect-msg ((query-selector (attribute-selector 'class "redirectMsg") body)))
             (define headers (if redirect-msg
                                 (let* ([dest (get-attribute 'href (bits->attributes ((query-selector (λ (t a c) (eq? t 'a)) redirect-msg))))]