From f2598ef8dfff0824037a02ec2fe53551569867d6 Mon Sep 17 00:00:00 2001
From: Nicholas Jitkoff <nicholas@jitkoff.com>
Date: Thu, 28 Jul 2022 09:39:42 -0400
Subject: [PATCH] Handle errors in metadata

---
 netlify/edge-functions/metadata.js | 110 +++++++++++++++--------------
 1 file changed, 57 insertions(+), 53 deletions(-)

diff --git a/netlify/edge-functions/metadata.js b/netlify/edge-functions/metadata.js
index 661a417..402d14c 100644
--- a/netlify/edge-functions/metadata.js
+++ b/netlify/edge-functions/metadata.js
@@ -18,64 +18,68 @@ function pathToMetadata(path) {
 }
 
 export default async (request, context) => {
-  const ua = request.headers.get("user-agent");
-  let url = new URL(request.url);
-  let path = url.pathname;
-  let geo = context?.geo?.city + ", " + context?.geo?.subdivision?.code + ", " + context?.geo?.country?.code
+  try {
+    const ua = request.headers.get("user-agent");
+    let url = new URL(request.url);
+    let path = url.pathname;
+    let geo = context?.geo?.city + ", " + context?.geo?.subdivision?.code + ", " + context?.geo?.country?.code
 
-  let uaArray = Deno.env.get("UA_ARRAY")?.split(",") || [];
-  let uaMatch = uaArray.some(a => ua.indexOf(a) != -1);
+    let uaArray = Deno.env.get("UA_ARRAY")?.split(",") || [];
+    let uaMatch = uaArray.some(a => ua.indexOf(a) != -1);
 
-  if (uaMatch) {
-    //console.log("Redirecting legacy client", )
-    return new Response('', { status: 401 });
-  }
-  
-  if (path != "/" ) {
-    // context.log(path, request.headers, geo);
-    let metadataBots = [ "Twitterbot", "curl", "facebookexternalhit", "Slackbot-LinkExpanding", "Discordbot", "snapchat"]
-    let isMetadataBot = metadataBots.some(bot => ua.indexOf(bot) != -1);
+    if (uaMatch) {
+      //console.log("Redirecting legacy client", )
+      return new Response('', { status: 401 });
+    }
+    
+    if (path != "/" ) {
+      // context.log(path, request.headers, geo);
+      let metadataBots = [ "Twitterbot", "curl", "facebookexternalhit", "Slackbot-LinkExpanding", "Discordbot", "snapchat"]
+      let isMetadataBot = metadataBots.some(bot => ua.indexOf(bot) != -1);
 
-    if (isMetadataBot && path.endsWith("/")) {
-      let info = pathToMetadata(path)
+      if (isMetadataBot && path.endsWith("/")) {
+        let info = pathToMetadata(path)
 
-      let content = ['<meta charset="UTF-8">'];
-      if (info.title) { content.push(`<title>${info.title}</title>`,`<meta property="og:title" content="${info.title}"/>`); }
-      if (info.s) { content.push(`<meta property="og:site_name" content="${info.s}"/>`); }
-      if (info.t) { content.push(`<meta property="og:type" content="${info.t}"/>`); }
-      if (info.d) { content.push(`<meta property="og:description" content="${info.d}"/>`,`<meta name="description" content="${info.d}"/>`); }
-      if (info.i) { 
-        if (!info.i.startsWith("http")) info.i = atob(info.i.replace(/=/g,''));
-        content.push(`<meta property="og:image" content="${info.i}"/>`); 
-        content.push(`<meta name="twitter:card" content="summary_large_image">`);
-        if (info.iw) content.push(`<meta property="og:image:width" content="${info.iw}"/>`); 
-        if (info.ih) content.push(`<meta property="og:image:width" content="${info.ih}"/>`); 
-      } 
-      if (info.c) { content.push(`<meta name="theme-color" content="#${info.c}"/>`); }
-      if (info.v) { 
-        if (!info.v.startsWith("http")) info.v = atob(info.v.replace(/=/g,''));
-        content.push(`<meta property="og:video" content="${info.v}"/>`); 
-        if (info.vw) content.push(`<meta property="og:image:width" content="${info.vw}"/>`); 
-        if (info.vh) content.push(`<meta property="og:image:width" content="${info.vh}"/>`); 
-      } 
-      if (info.f) {
-        if (info.f.length > 9){
-          if (!info.f.startsWith("http")) info.f = atob(info.f.replace(/=/g,''));
-          content.push(`<link rel="icon" type="image/png" href="${info.f}">`);
-        } else {
-          let codepoints = Array.from(info.f).map(c => c.codePointAt(0).toString(16));
-          content.push(`<link rel="icon" type="image/png" href="https://fonts.gstatic.com/s/e/notoemoji/14.0/${codepoints.join("_")}/128.png">`);
+        let content = ['<meta charset="UTF-8">'];
+        if (info.title) { content.push(`<title>${info.title}</title>`,`<meta property="og:title" content="${info.title}"/>`); }
+        if (info.s) { content.push(`<meta property="og:site_name" content="${info.s}"/>`); }
+        if (info.t) { content.push(`<meta property="og:type" content="${info.t}"/>`); }
+        if (info.d) { content.push(`<meta property="og:description" content="${info.d}"/>`,`<meta name="description" content="${info.d}"/>`); }
+        if (info.i) { 
+          if (!info.i.startsWith("http")) info.i = atob(info.i.replace(/=/g,''));
+          content.push(`<meta property="og:image" content="${info.i}"/>`); 
+          content.push(`<meta name="twitter:card" content="summary_large_image">`);
+          if (info.iw) content.push(`<meta property="og:image:width" content="${info.iw}"/>`); 
+          if (info.ih) content.push(`<meta property="og:image:width" content="${info.ih}"/>`); 
+        } 
+        if (info.c) { content.push(`<meta name="theme-color" content="#${info.c}"/>`); }
+        if (info.v) { 
+          if (!info.v.startsWith("http")) info.v = atob(info.v.replace(/=/g,''));
+          content.push(`<meta property="og:video" content="${info.v}"/>`); 
+          if (info.vw) content.push(`<meta property="og:image:width" content="${info.vw}"/>`); 
+          if (info.vh) content.push(`<meta property="og:image:width" content="${info.vh}"/>`); 
+        } 
+        if (info.f) {
+          if (info.f.length > 9){
+            if (!info.f.startsWith("http")) info.f = atob(info.f.replace(/=/g,''));
+            content.push(`<link rel="icon" type="image/png" href="${info.f}">`);
+          } else {
+            let codepoints = Array.from(info.f).map(c => c.codePointAt(0).toString(16));
+            content.push(`<link rel="icon" type="image/png" href="https://fonts.gstatic.com/s/e/notoemoji/14.0/${codepoints.join("_")}/128.png">`);
+          }
         }
-      }
-      content.push(`<meta property="og:url" content="${request.url}" />`);
-      
-      console.log(["Metadata Request", JSON.stringify(info), geo, ua].join('\t')); 
+        content.push(`<meta property="og:url" content="${request.url}" />`);
+        
+        console.log(["Metadata Request", JSON.stringify(info), geo, ua].join('\t')); 
 
-      return new Response(content.join("\n"), {
-        headers: { "content-type": "text/html" },
-      });
-    } 
-  } else {
-    console.log(["Request", path, geo, request.headers.get("referer"), ua].join('\t'));
+        return new Response(content.join("\n"), {
+          headers: { "content-type": "text/html" },
+        });
+      } 
+    } else {
+      console.log(["Request", path, geo, request.headers.get("referer"), ua].join('\t'));
+    }
+  } catch (e) {
+    console.log("Error:", request.url, e)
   }
 }