always use crc32 for etag, much more reliable than mojang skin hash

had to make quite a few changes to tests to prevent them from failing
also, etag is now only sent with a 200 response, as defined in RFC7232

lib/networking.js

@@ -13,40 +13,6 @@ var mojang_urls = [skins_url, capes_url];
 
 var exp = {};
 
-// extracts the +type+ [SKIN|CAPE] URL
-// from the nested & encoded +profile+ object
-// returns the URL or null if not present
-function extract_url(profile, type) {
-  var url = null;
-  if (profile && profile.properties) {
-    profile.properties.forEach(function(prop) {
-      if (prop.name === "textures") {
-        var json = new Buffer(prop.value, "base64").toString();
-        var props = JSON.parse(json);
-        url = Object.get(props, "textures." + type + ".url") || null;
-      }
-    });
-  }
-  return url;
-}
-
-// extracts the +type+ [SKIN|CAPE] URL
-// from the nested & encoded +profile+ object
-// returns the if the model is "slim"
-function extract_model(profile) {
-  var slim = null;
-  if (profile && profile.properties) {
-    profile.properties.forEach(function(prop) {
-      if (prop.name === "textures") {
-        var json = new Buffer(prop.value, "base64").toString();
-        var props = JSON.parse(json);
-        slim = Object.get(props, "textures.SKIN.metadata.model");
-      }
-    });
-  }
-  return slim === "slim";
-}
-
 // helper method that calls `get_username_url` or `get_uuid_info` based on the +usedId+
 // +userId+ is used for usernames, while +profile+ is used for UUIDs
 // callback: error, url, slim

lib/response.js

@@ -63,19 +63,15 @@ module.exports = function(request, response, result) {
     headers["X-Storage-Type"] = human_status[result.status];
   }
 
-  if (result.body) {
-    // use Mojang's image hash if available
-    // use crc32 as a hash function otherwise
-    var etag = result.hash && result.hash.substr(0, 10) || crc(result.body);
-    headers.Etag = "\"" + etag + "\"";
+  // use crc32 as a hash function for Etag
+  var etag = "\"" + crc(result.body || "") + "\"";
 
-    // handle etag caching
-    var incoming_etag = request.headers["if-none-match"];
-    if (incoming_etag && incoming_etag === headers.Etag) {
-      response.writeHead(304, headers);
-      response.end();
-      return;
-    }
+  // handle etag caching
+  var incoming_etag = request.headers["if-none-match"];
+  if (incoming_etag && incoming_etag === etag) {
+    response.writeHead(304, headers);
+    response.end();
+    return;
   }
 
   if (result.redirect) {
@@ -87,12 +83,16 @@ module.exports = function(request, response, result) {
 
   if (result.status === -2) {
     response.writeHead(result.code || 422, headers);
-    response.end(result.body);
   } else if (result.status === -1) {
     response.writeHead(500, headers);
-    response.end(result.body);
   } else {
-    response.writeHead(result.body ? 200 : 404, headers);
-    response.end(result.body);
+    if (result.body) {
+      headers.Etag = etag;
+      response.writeHead(200, headers);
+    } else {
+      response.writeHead(404, headers);
+    }
   }
+
+  response.end(result.body);
 };

test/test.js

@@ -236,7 +236,6 @@ describe("Crafatar", function() {
         assert.ifError(error);
         assert.ifError(body);
         assert.equal(res.statusCode, 304);
-        assert(res.headers.etag);
         assert_headers(res);
         callback();
       });
@@ -341,440 +340,396 @@ describe("Crafatar", function() {
     var server_tests = {
       "avatar with existing username": {
         url: "http://localhost:3000/avatars/jeb_?size=16",
-        etag: '"a846b82963"',
-        crc32: 1623808067
+        crc32: [1623808067]
       },
       "avatar with non-existent username": {
         url: "http://localhost:3000/avatars/0?size=16",
-        etag: '"mhf_steve"',
         crc32: [2416827277, 1243826040]
       },
       "avatar with non-existent username defaulting to mhf_alex": {
         url: "http://localhost:3000/avatars/0?size=16&default=mhf_alex",
-        etag: '"mhf_alex"',
         crc32: [862751081, 809395677]
       },
       "avatar with non-existent username defaulting to username": {
         url: "http://localhost:3000/avatars/0?size=16&default=jeb_",
-        crc32: 0,
+        crc32: [0],
         redirect: "/avatars/jeb_?size=16"
       },
       "avatar with non-existent username defaulting to uuid": {
         url: "http://localhost:3000/avatars/0?size=16&default=853c80ef3c3749fdaa49938b674adae6",
-        crc32: 0,
+        crc32: [0],
         redirect: "/avatars/853c80ef3c3749fdaa49938b674adae6?size=16"
       },
       "avatar with non-existent username defaulting to url": {
         url: "http://localhost:3000/avatars/0?size=16&default=http%3A%2F%2Fexample.com%2FCaseSensitive",
-        crc32: 0,
+        crc32: [0],
         redirect: "http://example.com/CaseSensitive"
       },
       "overlay avatar with existing username": {
         url: "http://localhost:3000/avatars/jeb_?size=16&overlay",
-        etag: '"a846b82963"',
-        crc32: 646871998
+        crc32: [646871998]
       },
       "overlay avatar with non-existent username": {
         url: "http://localhost:3000/avatars/0?size=16&overlay",
-        etag: '"mhf_steve"',
         crc32: [2416827277, 1243826040]
       },
       "overlay avatar with non-existent username defaulting to mhf_alex": {
         url: "http://localhost:3000/avatars/0?size=16&overlay&default=mhf_alex",
-        etag: '"mhf_alex"',
         crc32: [862751081, 809395677]
       },
       "overlay avatar with non-existent username defaulting to username": {
         url: "http://localhost:3000/avatars/0?size=16&overlay&default=jeb_",
-        crc32: 0,
+        crc32: [0],
         redirect: "/avatars/jeb_?size=16&overlay="
       },
       "overlay avatar with non-existent username defaulting to uuid": {
         url: "http://localhost:3000/avatars/0?size=16&overlay&default=853c80ef3c3749fdaa49938b674adae6",
-        crc32: 0,
+        crc32: [0],
         redirect: "/avatars/853c80ef3c3749fdaa49938b674adae6?size=16&overlay="
       },
       "overlay avatar with non-existent username defaulting to url": {
         url: "http://localhost:3000/avatars/0?size=16&overlay&default=http%3A%2F%2Fexample.com%2FCaseSensitive",
-        crc32: 0,
+        crc32: [0],
         redirect: "http://example.com/CaseSensitive"
       },
       "avatar with existing uuid": {
         url: "http://localhost:3000/avatars/853c80ef3c3749fdaa49938b674adae6?size=16",
-        etag: '"a846b82963"',
-        crc32: 1623808067
+        crc32: [1623808067]
       },
       "avatar with non-existent uuid": {
         url: "http://localhost:3000/avatars/00000000000000000000000000000000?size=16",
-        etag: '"mhf_steve"',
         crc32: [2416827277, 1243826040]
       },
       "avatar with non-existent uuid defaulting to mhf_alex": {
         url: "http://localhost:3000/avatars/00000000000000000000000000000000?size=16&default=mhf_alex",
-        etag: '"mhf_alex"',
         crc32: [862751081, 809395677]
       },
       "avatar with non-existent uuid defaulting to username": {
         url: "http://localhost:3000/avatars/00000000000000000000000000000000?size=16&default=jeb_",
-        crc32: 0,
+        crc32: [0],
         redirect: "/avatars/jeb_?size=16"
       },
       "avatar with non-existent uuid defaulting to uuid": {
         url: "http://localhost:3000/avatars/00000000000000000000000000000000?size=16&default=853c80ef3c3749fdaa49938b674adae6",
-        crc32: 0,
+        crc32: [0],
         redirect: "/avatars/853c80ef3c3749fdaa49938b674adae6?size=16"
       },
       "avatar with non-existent uuid defaulting to url": {
         url: "http://localhost:3000/avatars/00000000000000000000000000000000?size=16&default=http%3A%2F%2Fexample.com%2FCaseSensitive",
-        crc32: 0,
+        crc32: [0],
         redirect: "http://example.com/CaseSensitive"
       },
       "overlay avatar with existing uuid": {
         url: "http://localhost:3000/avatars/853c80ef3c3749fdaa49938b674adae6?size=16&overlay",
-        etag: '"a846b82963"',
-        crc32: 646871998
+        crc32: [646871998]
       },
       "overlay avatar with non-existent uuid": {
         url: "http://localhost:3000/avatars/00000000000000000000000000000000?size=16&overlay",
-        etag: '"mhf_steve"',
         crc32: [2416827277, 1243826040]
       },
       "overlay avatar with non-existent uuid defaulting to mhf_alex": {
         url: "http://localhost:3000/avatars/00000000000000000000000000000000?size=16&overlay&default=mhf_alex",
-        etag: '"mhf_alex"',
         crc32: [862751081, 809395677]
       },
       "overlay avatar with non-existent uuid defaulting to username": {
         url: "http://localhost:3000/avatars/00000000000000000000000000000000?size=16&default=jeb_",
-        crc32: 0,
+        crc32: [0],
         redirect: "/avatars/jeb_?size=16"
       },
       "overlay avatar with non-existent uuid defaulting to uuid": {
         url: "http://localhost:3000/avatars/00000000000000000000000000000000?size=16&default=853c80ef3c3749fdaa49938b674adae6",
-        crc32: 0,
+        crc32: [0],
         redirect: "/avatars/853c80ef3c3749fdaa49938b674adae6?size=16"
       },
       "overlay avatar with non-existent uuid defaulting to url": {
         url: "http://localhost:3000/avatars/00000000000000000000000000000000?size=16&overlay&default=http%3A%2F%2Fexample.com%2FCaseSensitive",
-        crc32: 0,
+        crc32: [0],
         redirect: "http://example.com/CaseSensitive"
       },
       "cape with existing username": {
         url: "http://localhost:3000/capes/jeb_",
-        etag: '"3f688e0e69"',
         crc32: [989800403, 1901140141]
       },
       "cape with non-existent username": {
         url: "http://localhost:3000/capes/0",
-        crc32: 0
+        crc32: [0]
       },
       "cape with non-existent username defaulting to url": {
         url: "http://localhost:3000/capes/0?default=http%3A%2F%2Fexample.com%2FCaseSensitive",
-        crc32: 0,
+        crc32: [0],
         redirect: "http://example.com/CaseSensitive"
       },
       "cape with existing uuid": {
         url: "http://localhost:3000/capes/853c80ef3c3749fdaa49938b674adae6",
-        etag: '"3f688e0e69"',
         crc32: [989800403, 1901140141]
       },
       "cape with non-existent uuid": {
         url: "http://localhost:3000/capes/00000000000000000000000000000000",
-        crc32: 0
+        crc32: [0]
       },
       "cape with non-existent uuid defaulting to url": {
         url: "http://localhost:3000/capes/00000000000000000000000000000000?default=http%3A%2F%2Fexample.com%2FCaseSensitive",
-        crc32: 0,
+        crc32: [0],
         redirect: "http://example.com/CaseSensitive"
       },
       "skin with existing username": {
         url: "http://localhost:3000/skins/jeb_",
-        etag: '"a846b82963"',
-        crc32: 26500336
+        crc32: [26500336]
       },
       "skin with non-existent username": {
         url: "http://localhost:3000/skins/0",
-        etag: '"mhf_steve"',
-        crc32: 981937087
+        crc32: [981937087]
       },
       "skin with non-existent username defaulting to mhf_alex": {
         url: "http://localhost:3000/skins/0?default=mhf_alex",
-        etag: '"mhf_alex"',
-        crc32: 2298915739
+        crc32: [2298915739]
       },
       "skin with non-existent username defaulting to username": {
         url: "http://localhost:3000/skins/0?size=16&default=jeb_",
-        crc32: 0,
+        crc32: [0],
         redirect: "/skins/jeb_?size=16"
       },
       "skin with non-existent username defaulting to uuid": {
         url: "http://localhost:3000/skins/0?size=16&default=853c80ef3c3749fdaa49938b674adae6",
-        crc32: 0,
+        crc32: [0],
         redirect: "/skins/853c80ef3c3749fdaa49938b674adae6?size=16"
       },
       "skin with non-existent username defaulting to url": {
         url: "http://localhost:3000/skins/0?default=http%3A%2F%2Fexample.com%2FCaseSensitive",
-        crc32: 0,
+        crc32: [0],
         redirect: "http://example.com/CaseSensitive"
       },
       "skin with existing uuid": {
         url: "http://localhost:3000/skins/853c80ef3c3749fdaa49938b674adae6",
-        etag: '"a846b82963"',
-        crc32: 26500336
+        crc32: [26500336]
       },
       "skin with non-existent uuid": {
         url: "http://localhost:3000/skins/00000000000000000000000000000000",
-        etag: '"mhf_steve"',
-        crc32: 981937087
+        crc32: [981937087]
       },
       "skin with non-existent uuid defaulting to mhf_alex": {
         url: "http://localhost:3000/skins/00000000000000000000000000000000?default=mhf_alex",
-        etag: '"mhf_alex"',
-        crc32: 2298915739
+        crc32: [2298915739]
       },
       "skin with non-existent uuid defaulting to username": {
         url: "http://localhost:3000/skins/00000000000000000000000000000000?size=16&default=jeb_",
-        crc32: 0,
+        crc32: [0],
         redirect: "/skins/jeb_?size=16"
       },
       "skin with non-existent uuid defaulting to uuid": {
         url: "http://localhost:3000/skins/00000000000000000000000000000000?size=16&default=853c80ef3c3749fdaa49938b674adae6",
-        crc32: 0,
+        crc32: [0],
         redirect: "/skins/853c80ef3c3749fdaa49938b674adae6?size=16"
       },
       "skin with non-existent uuid defaulting to url": {
         url: "http://localhost:3000/skins/00000000000000000000000000000000?default=http%3A%2F%2Fexample.com%2FCaseSensitive",
-        crc32: 0,
+        crc32: [0],
         redirect: "http://example.com/CaseSensitive"
       },
       "head render with existing username": {
         url: "http://localhost:3000/renders/head/jeb_?scale=2",
-        etag: '"a846b82963"',
         crc32: [3487896679, 3001090792]
       },
       "head render with non-existent username": {
         url: "http://localhost:3000/renders/head/0?scale=2",
-        etag: '"mhf_steve"',
         crc32: [3257141069, 214248305]
       },
       "head render with non-existent username defaulting to mhf_alex": {
         url: "http://localhost:3000/renders/head/0?scale=2&default=mhf_alex",
-        etag: '"mhf_alex"',
         crc32: [263450586, 3116770561]
       },
       "head render with non-existent username defaulting to username": {
         url: "http://localhost:3000/avatars/0?scale=2&default=jeb_",
-        crc32: 0,
+        crc32: [0],
         redirect: "/avatars/jeb_?scale=2"
       },
       "head render with non-existent username defaulting to uuid": {
         url: "http://localhost:3000/avatars/0?scale=2&default=853c80ef3c3749fdaa49938b674adae6",
-        crc32: 0,
+        crc32: [0],
         redirect: "/avatars/853c80ef3c3749fdaa49938b674adae6?scale=2"
       },
       "head render with non-existent username defaulting to url": {
         url: "http://localhost:3000/renders/head/0?scale=2&default=http%3A%2F%2Fexample.com%2FCaseSensitive",
-        crc32: 0,
+        crc32: [0],
         redirect: "http://example.com/CaseSensitive"
       },
       "overlay head render with existing username": {
         url: "http://localhost:3000/renders/head/jeb_?scale=2&overlay",
-        etag: '"a846b82963"',
         crc32: [762377383, 1726474987]
       },
       "overlay head render with non-existent username": {
         url: "http://localhost:3000/renders/head/0?scale=2&overlay",
-        etag: '"mhf_steve"',
         crc32: [3257141069, 214248305]
       },
       "overlay head render with non-existent username defaulting to mhf_alex": {
         url: "http://localhost:3000/renders/head/0?scale=2&overlay&default=mhf_alex",
-        etag: '"mhf_alex"',
         crc32: [263450586, 3116770561]
       },
       "overlay head render with non-existent username defaulting to username": {
         url: "http://localhost:3000/renders/head/0?scale=2&overlay&default=jeb_",
-        crc32: 0,
+        crc32: [0],
         redirect: "/renders/head/jeb_?scale=2&overlay="
       },
       "overlay head render with non-existent username defaulting to uuid": {
         url: "http://localhost:3000/renders/head/0?scale=2&overlay&default=853c80ef3c3749fdaa49938b674adae6",
-        crc32: 0,
+        crc32: [0],
         redirect: "/renders/head/853c80ef3c3749fdaa49938b674adae6?scale=2&overlay="
       },
       "overlay head render with non-existent username defaulting to url": {
         url: "http://localhost:3000/renders/head/0?scale=2&overlay&default=http%3A%2F%2Fexample.com%2FCaseSensitive",
-        crc32: 0,
+        crc32: [0],
         redirect: "http://example.com/CaseSensitive"
       },
       "head render with existing uuid": {
         url: "http://localhost:3000/renders/head/853c80ef3c3749fdaa49938b674adae6?scale=2",
-        etag: '"a846b82963"',
         crc32: [3487896679, 3001090792]
       },
       "head render with non-existent uuid": {
         url: "http://localhost:3000/renders/head/00000000000000000000000000000000?scale=2",
-        etag: '"mhf_steve"',
         crc32: [3257141069, 214248305]
       },
       "head render with non-existent uuid defaulting to mhf_alex": {
         url: "http://localhost:3000/renders/head/00000000000000000000000000000000?scale=2&default=mhf_alex",
-        etag: '"mhf_alex"',
         crc32: [263450586, 3116770561]
       },
       "head render with non-existent uuid defaulting to username": {
         url: "http://localhost:3000/renders/head/00000000000000000000000000000000?scale=2&default=jeb_",
-        crc32: 0,
+        crc32: [0],
         redirect: "/renders/head/jeb_?scale=2"
       },
       "head render with non-existent uuid defaulting to uuid": {
         url: "http://localhost:3000/renders/head/00000000000000000000000000000000?scale=2&default=853c80ef3c3749fdaa49938b674adae6",
-        crc32: 0,
+        crc32: [0],
         redirect: "/renders/head/853c80ef3c3749fdaa49938b674adae6?scale=2"
       },
       "head render with non-existent uuid defaulting to url": {
         url: "http://localhost:3000/renders/head/00000000000000000000000000000000?scale=2&default=http%3A%2F%2Fexample.com%2FCaseSensitive",
-        crc32: 0,
+        crc32: [0],
         redirect: "http://example.com/CaseSensitive"
       },
       "overlay head render with existing uuid": {
         url: "http://localhost:3000/renders/head/853c80ef3c3749fdaa49938b674adae6?scale=2&overlay",
-        etag: '"a846b82963"',
         crc32: [762377383, 1726474987]
       },
       "overlay head render with non-existent uuid": {
         url: "http://localhost:3000/renders/head/00000000000000000000000000000000?scale=2&overlay",
-        etag: '"mhf_steve"',
         crc32: [3257141069, 214248305]
       },
       "overlay head render with non-existent uuid defaulting to mhf_alex": {
         url: "http://localhost:3000/renders/head/00000000000000000000000000000000?scale=2&overlay&default=mhf_alex",
-        etag: '"mhf_alex"',
         crc32: [263450586, 3116770561]
       },
       "overlay head with non-existent uuid defaulting to username": {
         url: "http://localhost:3000/renders/head/00000000000000000000000000000000?scale=2&overlay&default=jeb_",
-        crc32: 0,
+        crc32: [0],
         redirect: "/renders/head/jeb_?scale=2&overlay="
       },
       "overlay head with non-existent uuid defaulting to uuid": {
         url: "http://localhost:3000/renders/head/00000000000000000000000000000000?scale=2&overlay&default=853c80ef3c3749fdaa49938b674adae6",
-        crc32: 0,
+        crc32: [0],
         redirect: "/renders/head/853c80ef3c3749fdaa49938b674adae6?scale=2&overlay="
       },
       "overlay head render with non-existent uuid defaulting to url": {
         url: "http://localhost:3000/renders/head/00000000000000000000000000000000?scale=2&overlay&default=http%3A%2F%2Fexample.com%2FCaseSensitive",
-        crc32: 0,
+        crc32: [0],
         redirect: "http://example.com/CaseSensitive"
       },
       "body render with existing username": {
         url: "http://localhost:3000/renders/body/jeb_?scale=2",
-        etag: '"a846b82963"',
         crc32: [3127075871, 2595192206]
       },
       "body render with non-existent username": {
         url: "http://localhost:3000/renders/body/0?scale=2",
-        etag: '"mhf_steve"',
         crc32: [1046655221, 1620063267]
       },
       "body render with non-existent username defaulting to mhf_alex": {
         url: "http://localhost:3000/renders/body/0?scale=2&default=mhf_alex",
-        etag: '"mhf_alex"',
         crc32: [549240598, 3952648540]
       },
       "body render with non-existent username defaulting to username": {
         url: "http://localhost:3000/renders/body/0?scale=2&default=jeb_",
-        crc32: 0,
+        crc32: [0],
         redirect: "/renders/body/jeb_?scale=2"
       },
       "body render with non-existent username defaulting to uuid": {
         url: "http://localhost:3000/renders/body/0?scale=2&default=853c80ef3c3749fdaa49938b674adae6",
-        crc32: 0,
+        crc32: [0],
         redirect: "/renders/body/853c80ef3c3749fdaa49938b674adae6?scale=2"
       },
       "body render with non-existent username defaulting to url": {
         url: "http://localhost:3000/renders/body/0?scale=2&default=http%3A%2F%2Fexample.com%2FCaseSensitive",
-        crc32: 0,
+        crc32: [0],
         redirect: "http://example.com/CaseSensitive"
       },
       "overlay body render with existing username": {
         url: "http://localhost:3000/renders/body/jeb_?scale=2&overlay",
-        etag: '"a846b82963"',
         crc32: [699892097, 2732138694]
       },
       "overlay body render with non-existent username": {
         url: "http://localhost:3000/renders/body/0?scale=2&overlay",
-        etag: '"mhf_steve"',
         crc32: [1046655221, 1620063267]
       },
       "overlay body render with non-existent username defaulting to mhf_alex": {
         url: "http://localhost:3000/renders/body/0?scale=2&overlay&default=mhf_alex",
-        etag: '"mhf_alex"',
         crc32: [549240598, 3952648540]
       },
       "overlay body render with non-existent username defaulting to username": {
         url: "http://localhost:3000/renders/body/0?scale=2&overlay&default=jeb_",
-        crc32: 0,
+        crc32: [0],
         redirect: "/renders/body/jeb_?scale=2&overlay="
       },
       "overlay body render with non-existent username defaulting to uuid": {
         url: "http://localhost:3000/renders/body/0?scale=2&overlay&default=853c80ef3c3749fdaa49938b674adae6",
-        crc32: 0,
+        crc32: [0],
         redirect: "/renders/body/853c80ef3c3749fdaa49938b674adae6?scale=2&overlay="
       },
       "overlay body render with non-existent username defaulting to url": {
         url: "http://localhost:3000/renders/body/0?scale=2&overlay&default=http%3A%2F%2Fexample.com%2FCaseSensitive",
-        crc32: 0,
+        crc32: [0],
         redirect: "http://example.com/CaseSensitive"
       },
       "body render with existing uuid": {
         url: "http://localhost:3000/renders/body/853c80ef3c3749fdaa49938b674adae6?scale=2",
-        etag: '"a846b82963"',
         crc32: [3127075871, 2595192206]
       },
       "body render with non-existent uuid": {
         url: "http://localhost:3000/renders/body/00000000000000000000000000000000?scale=2",
-        etag: '"mhf_steve"',
         crc32: [1046655221, 1620063267]
       },
       "body render with non-existent uuid defaulting to mhf_alex": {
         url: "http://localhost:3000/renders/body/00000000000000000000000000000000?scale=2&default=mhf_alex",
-        etag: '"mhf_alex"',
         crc32: [549240598, 3952648540]
       },
       "body render with non-existent uuid defaulting to username": {
         url: "http://localhost:3000/renders/body/0?scale=2&default=jeb_",
-        crc32: 0,
+        crc32: [0],
         redirect: "/renders/body/jeb_?scale=2"
       },
       "body render with non-existent uuid defaulting to uuid": {
         url: "http://localhost:3000/renders/body/0?scale=2&default=853c80ef3c3749fdaa49938b674adae6",
-        crc32: 0,
+        crc32: [0],
         redirect: "/renders/body/853c80ef3c3749fdaa49938b674adae6?scale=2"
       },
       "body render with non-existent uuid defaulting to url": {
         url: "http://localhost:3000/renders/body/00000000000000000000000000000000?scale=2&default=http%3A%2F%2Fexample.com%2FCaseSensitive",
-        crc32: 0,
+        crc32: [0],
         redirect: "http://example.com/CaseSensitive"
       },
       "overlay body render with existing uuid": {
         url: "http://localhost:3000/renders/body/853c80ef3c3749fdaa49938b674adae6?scale=2&overlay",
-        etag: '"a846b82963"',
         crc32: [699892097, 2732138694]
       },
       "overlay body render with non-existent uuid": {
         url: "http://localhost:3000/renders/body/00000000000000000000000000000000?scale=2&overlay",
-        etag: '"mhf_steve"',
         crc32: [1046655221, 1620063267]
       },
       "overlay body render with non-existent uuid defaulting to mhf_alex": {
         url: "http://localhost:3000/renders/body/00000000000000000000000000000000?scale=2&overlay&default=mhf_alex",
-        etag: '"mhf_alex"',
         crc32: [549240598, 3952648540]
       },
       "overlay body render with non-existent uuid defaulting to url": {
         url: "http://localhost:3000/renders/body/00000000000000000000000000000000?scale=2&overlay&default=http%3A%2F%2Fexample.com%2FCaseSensitive",
-        crc32: 0,
+        crc32: [0],
         redirect: "http://example.com/CaseSensitive"
       },
     };
@@ -787,32 +742,30 @@ describe("Crafatar", function() {
             assert.ifError(error);
             assert_headers(res);
             assert(res.headers["x-storage-type"]);
-            assert.strictEqual(res.headers.etag, location.etag);
+            var hash = crc(body);
             var matches = false;
-            if (location.crc32 instanceof Array) {
-              for (var i = 0; i < location.crc32.length; i++) {
-                if (location.crc32[i] === crc(body)) {
-                  matches = true;
-                  break;
-                }
+            for (var c = 0; c < location.crc32.length; c++) {
+              if (location.crc32[c] === hash) {
+                matches = true;
+                break;
               }
-            } else {
-              matches = location.crc32 === crc(body);
             }
             try {
-              assert.ok(matches);
+              assert(matches);
             } catch(e) {
-              throw new Error(crc(body) + " != " + location.crc32 + " | " + body.toString("base64"));
+              throw new Error(hash + " != " + location.crc32 + " | " + body.toString("base64"));
             }
             assert.strictEqual(res.headers.location, location.redirect);
-            if (location.etag === undefined) {
+            if (location.crc32[0] === 0) {
               assert.strictEqual(res.statusCode, location.redirect ? 307 : 404);
+              assert.ifError(res.headers.etag); // etag must not be present on non-200
               assert.strictEqual(res.headers["content-type"], "text/plain");
               done();
             } else {
-              assert(res.headers.etag);
               assert.strictEqual(res.headers["content-type"], "image/png");
               assert.strictEqual(res.statusCode, 200);
+              assert(res.headers.etag);
+              assert.strictEqual(res.headers.etag, '"' + hash + '"');
               assert_cache(location.url, res.headers.etag, function() {
                 done();
               });