Support aspect ratio specification for native images

modules/appnexusAstBidAdapter.js

@@ -14,13 +14,15 @@ const NATIVE_MAPPING = {
   cta: 'ctatext',
   image: {
     serverName: 'main_image',
-    serverParams: { required: true, sizes: [{}] }
+    requiredParams: { required: true },
+    minimumParams: { sizes: [{}] },
   },
   icon: {
     serverName: 'icon',
-    serverParams: { required: true, sizes: [{}] }
+    requiredParams: { required: true },
+    minimumParams: { sizes: [{}] },
   },
-  sponsoredBy: 'sponsored_by'
+  sponsoredBy: 'sponsored_by',
 };
 const SOURCE = 'pbjs';
 
@@ -264,28 +266,7 @@ function bidToTag(bid) {
     tag.ad_types = ['native'];
 
     if (bid.nativeParams) {
-      const nativeRequest = {};
-
-      // map standard prebid native asset identifier to /ut parameters
-      // e.g., tag specifies `body` but /ut only knows `description`
-      // mapping may be in form {tag: '<server name>'} or
-      // {tag: {serverName: '<server name>', serverParams: {...}}}
-      Object.keys(bid.nativeParams).forEach(key => {
-        // check if one of the <server name> forms is used, otherwise
-        // a mapping wasn't specified so pass the key straight through
-        const requestKey =
-          (NATIVE_MAPPING[key] && NATIVE_MAPPING[key].serverName) ||
-          NATIVE_MAPPING[key] ||
-          key;
-
-        // if the mapping for this identifier specifies required server
-        // params via the `serverParams` object, merge that in
-        nativeRequest[requestKey] = Object.assign({},
-          NATIVE_MAPPING[key] && NATIVE_MAPPING[key].serverParams,
-          bid.nativeParams[key]
-        );
-      });
-
+      const nativeRequest = buildNativeRequest(bid.nativeParams);
       tag['native'] = {layouts: [nativeRequest]};
     }
   }
@@ -343,6 +324,44 @@ function getRtbBid(tag) {
   return tag && tag.ads && tag.ads.length && tag.ads.find(ad => ad.rtb);
 }
 
+function buildNativeRequest(params) {
+  const request = {};
+
+  // map standard prebid native asset identifier to /ut parameters
+  // e.g., tag specifies `body` but /ut only knows `description`.
+  // mapping may be in form {tag: '<server name>'} or
+  // {tag: {serverName: '<server name>', requiredParams: {...}}}
+  Object.keys(params).forEach(key => {
+    // check if one of the <server name> forms is used, otherwise
+    // a mapping wasn't specified so pass the key straight through
+    const requestKey =
+      (NATIVE_MAPPING[key] && NATIVE_MAPPING[key].serverName) ||
+      NATIVE_MAPPING[key] ||
+      key;
+
+    // required params are always passed on request
+    const requiredParams = NATIVE_MAPPING[key] && NATIVE_MAPPING[key].requiredParams;
+    request[requestKey] = Object.assign({}, requiredParams, params[key]);
+
+    // minimum params are passed if no non-required params given on adunit
+    const minimumParams = NATIVE_MAPPING[key] && NATIVE_MAPPING[key].minimumParams;
+
+    if (requiredParams && minimumParams) {
+      // subtract required keys from adunit keys
+      const adunitKeys = Object.keys(params[key]);
+      const requiredKeys = Object.keys(requiredParams);
+      const remaining = adunitKeys.filter(key => !requiredKeys.includes(key));
+
+      // if none are left over, the minimum params needs to be sent
+      if (remaining.length === 0) {
+        request[requestKey] = Object.assign({}, request[requestKey], minimumParams);
+      }
+    }
+  });
+
+  return request;
+}
+
 function outstreamRender(bid) {
   // push to render queue because ANOutstreamVideo may not be loaded yet
   bid.renderer.push(() => {

test/spec/modules/appnexusAstBidAdapter_spec.js

@@ -164,7 +164,7 @@ describe('AppNexusAdapter', () => {
       delete REQUEST.bids[0].params.nativeParams;
     });
 
-    it('sets required native asset params when not provided on adunit', () => {
+    it('sets minimum native asset params when not provided on adunit', () => {
       REQUEST.bids[0].mediaType = 'native';
       REQUEST.bids[0].nativeParams = {
         image: {required: true},
@@ -181,6 +181,36 @@ describe('AppNexusAdapter', () => {
       delete REQUEST.bids[0].params.nativeParams;
     });
 
+    it('does not overwrite native ad unit params with mimimum params', () => {
+      REQUEST.bids[0].mediaType = 'native';
+      REQUEST.bids[0].nativeParams = {
+        image: {
+          aspect_ratios: [{
+            min_width: 100,
+            ratio_width: 2,
+            ratio_height: 3,
+          }]
+        },
+      };
+
+      adapter.callBids(REQUEST);
+
+      const request = JSON.parse(requests[0].requestBody);
+      expect(request.tags[0].native.layouts[0]).to.deep.equal({
+        main_image: {
+          required: true,
+          aspect_ratios: [{
+            min_width: 100,
+            ratio_width: 2,
+            ratio_height: 3,
+          }]
+        },
+      });
+
+      delete REQUEST.bids[0].mediaType;
+      delete REQUEST.bids[0].params.nativeParams;
+    });
+
     it('sends bid request to ENDPOINT via POST', () => {
       adapter.callBids(REQUEST);
       expect(requests[0].url).to.equal(ENDPOINT);