Support bidder-specific device data

This PR introduces support for bidder-specific device data. It merges
bidderconfig.ortb2.device fields into request.device, with
bidderconfig.ortb2.device taking precedence.
Fixes #4147

exchange/utils.go

@@ -1009,6 +1009,10 @@ func applyFPD(fpd map[openrtb_ext.BidderName]*firstpartydata.ResolvedFirstPartyD
 		reqWrapper.App = fpdToApply.App
 	}
 
+	if fpdToApply.Device != nil {
+		reqWrapper.Device = fpdToApply.Device
+	}
+
 	if fpdToApply.User != nil {
 		if reqWrapper.User != nil {
 			if len(reqWrapper.User.BuyerUID) > 0 {

exchange/utils_test.go

@@ -3794,6 +3794,17 @@ func TestApplyFPD(t *testing.T) {
 			expectedRequest:           openrtb2.BidRequest{Site: &openrtb2.Site{ID: "SiteId"}, App: &openrtb2.App{ID: "AppId"}, User: &openrtb2.User{ID: "UserId", EIDs: []openrtb2.EID{{Source: "source3"}, {Source: "source4"}}}},
 			fpdUserEIDsExisted:        false,
 		},
+		{
+			description: "req.Device defined; bidderFPD.Device defined; expect request.Device to be overriden by bidderFPD.Device",
+			inputFpd: map[openrtb_ext.BidderName]*firstpartydata.ResolvedFirstPartyData{
+				"bidderNormalized": {Device: &openrtb2.Device{Make: "DeviceMake"}},
+			},
+			inputBidderName:           "bidderFromRequest",
+			inputBidderCoreName:       "bidderNormalized",
+			inputBidderIsRequestAlias: false,
+			inputRequest:              openrtb2.BidRequest{Device: &openrtb2.Device{Make: "TestDeviceMake"}},
+			expectedRequest:           openrtb2.BidRequest{Device: &openrtb2.Device{Make: "DeviceMake"}},
+		},
 	}
 
 	for _, testCase := range testCases {

firstpartydata/first_party_data.go

@@ -32,9 +32,10 @@ const (
 )
 
 type ResolvedFirstPartyData struct {
-	Site *openrtb2.Site
-	App  *openrtb2.App
-	User *openrtb2.User
+	Site   *openrtb2.Site
+	App    *openrtb2.App
+	User   *openrtb2.User
+	Device *openrtb2.Device
 }
 
 // ExtractGlobalFPD extracts request level FPD from the request and removes req.{site,app,user}.ext.data if exists
@@ -159,13 +160,49 @@ func ResolveFPD(bidRequest *openrtb2.BidRequest, fpdBidderConfigData map[openrtb
 		}
 		resolvedFpdConfig.Site = newSite
 
+		newDevice, err := resolveDevice(fpdConfig, bidRequest.Device)
+		if err != nil {
+			errL = append(errL, err)
+		}
+		resolvedFpdConfig.Device = newDevice
+
 		if len(errL) == 0 {
 			resolvedFpd[openrtb_ext.BidderName(bidderName)] = resolvedFpdConfig
 		}
 	}
 	return resolvedFpd, errL
 }
 
+// resolveDevice merges the device information from the FPD (First Party Data) configuration
+// with the device information provided in the bid request. It returns a new Device object
+// that contains the merged data.
+func resolveDevice(fpdConfig *openrtb_ext.ORTB2, bidRequestDevice *openrtb2.Device) (*openrtb2.Device, error) {
+	var fpdConfigDevice json.RawMessage
+
+	if fpdConfig != nil && fpdConfig.Device != nil {
+		fpdConfigDevice = fpdConfig.Device
+	}
+
+	if bidRequestDevice == nil && fpdConfigDevice == nil {
+		return nil, nil
+	}
+
+	var newDevice *openrtb2.Device
+	if bidRequestDevice != nil {
+		newDevice = ptrutil.Clone(bidRequestDevice)
+	} else {
+		newDevice = &openrtb2.Device{}
+	}
+
+	if fpdConfigDevice != nil {
+		if err := jsonutil.MergeClone(newDevice, fpdConfigDevice); err != nil {
+			return nil, formatMergeCloneError(err)
+		}
+	}
+
+	return newDevice, nil
+}
+
 func resolveUser(fpdConfig *openrtb_ext.ORTB2, bidRequestUser *openrtb2.User, globalFPD map[string][]byte, openRtbGlobalFPD map[string][]openrtb2.Data, bidderName string) (*openrtb2.User, error) {
 	var fpdConfigUser json.RawMessage
 
@@ -377,6 +414,7 @@ func ExtractBidderConfigFPD(reqExt *openrtb_ext.RequestExt) (map[openrtb_ext.Bid
 					fpdBidderData.Site = bidderConfig.Config.ORTB2.Site
 					fpdBidderData.App = bidderConfig.Config.ORTB2.App
 					fpdBidderData.User = bidderConfig.Config.ORTB2.User
+					fpdBidderData.Device = bidderConfig.Config.ORTB2.Device
 				}
 
 				fpd[bidderName] = fpdBidderData

firstpartydata/first_party_data_test.go

@@ -519,6 +519,12 @@ func TestExtractBidderConfigFPD(t *testing.T) {
 				} else {
 					assert.Nil(t, results[bidderName].User, "user expected to be nil")
 				}
+
+				if expectedFPD.Device != nil {
+					assert.JSONEq(t, string(expectedFPD.Device), string(results[bidderName].Device), "device is incorrect")
+				} else {
+					assert.Nil(t, results[bidderName].Device, "device expected to be nil")
+				}
 			}
 		})
 	}
@@ -625,6 +631,14 @@ func TestResolveFPD(t *testing.T) {
 						assert.JSONEq(t, string(expectedUserExt), string(resUserExt), "user.ext is incorrect")
 						assert.Equal(t, outputReq.User, bidderFPD.User, "User is incorrect")
 					}
+					if outputReq.Device != nil && len(outputReq.Device.Ext) > 0 {
+						resDeviceExt := bidderFPD.Device.Ext
+						expectedDeviceExt := outputReq.Device.Ext
+						bidderFPD.Device.Ext = nil
+						outputReq.Device.Ext = nil
+						assert.JSONEq(t, string(expectedDeviceExt), string(resDeviceExt), "device.ext is incorrect")
+						assert.Equal(t, outputReq.Device, bidderFPD.Device, "Device is incorrect")
+					}
 				}
 			} else {
 				assert.ElementsMatch(t, errL, testFile.ValidationErrors, "Incorrect first party data warning message")
@@ -1212,6 +1226,78 @@ func TestResolveApp(t *testing.T) {
 	}
 }
 
+func TestResolveDevice(t *testing.T) {
+	testCases := []struct {
+		description      string
+		fpdConfig        *openrtb_ext.ORTB2
+		bidRequestDevice *openrtb2.Device
+		expectedDevice   *openrtb2.Device
+		expectError      string
+	}{
+		{
+			description:    "FPD config and bid request device are not specified",
+			expectedDevice: nil,
+		},
+		{
+			description: "FPD config device only is specified",
+			fpdConfig:   &openrtb_ext.ORTB2{Device: json.RawMessage(`{"ua":"test-user-agent"}`)},
+			expectedDevice: &openrtb2.Device{
+				UA: "test-user-agent",
+			},
+		},
+		{
+			description:      "FPD config and bid request device are specified",
+			fpdConfig:        &openrtb_ext.ORTB2{Device: json.RawMessage(`{"ua":"test-user-agent-1"}`)},
+			bidRequestDevice: &openrtb2.Device{UA: "test-user-agent-2"},
+			expectedDevice:   &openrtb2.Device{UA: "test-user-agent-1"},
+		},
+		{
+			description:      "Bid request device only is specified",
+			bidRequestDevice: &openrtb2.Device{UA: "test-user-agent"},
+			expectedDevice:   &openrtb2.Device{UA: "test-user-agent"},
+		},
+		{
+			description: "FPD config device with ext, bid request device with ext",
+			fpdConfig:   &openrtb_ext.ORTB2{Device: json.RawMessage(`{"ua":"test-user-agent-1","ext":{"test":1}}`)},
+			bidRequestDevice: &openrtb2.Device{
+				UA:  "test-user-agent-2",
+				Ext: json.RawMessage(`{"test":2,"key":"value"}`),
+			},
+			expectedDevice: &openrtb2.Device{
+				UA:  "test-user-agent-1",
+				Ext: json.RawMessage(`{"key":"value","test":1}`),
+			},
+		},
+		{
+			description:      "Bid request device with ext only is specified",
+			bidRequestDevice: &openrtb2.Device{UA: "test-user-agent", Ext: json.RawMessage(`{"customData":true}`)},
+			expectedDevice:   &openrtb2.Device{UA: "test-user-agent", Ext: json.RawMessage(`{"customData":true}`)},
+		},
+		{
+			description: "FPD config device with malformed ext",
+			fpdConfig:   &openrtb_ext.ORTB2{Device: json.RawMessage(`{"ua":"test-user-agent-1","ext":{malformed}}`)},
+			bidRequestDevice: &openrtb2.Device{
+				UA:  "test-user-agent-2",
+				Ext: json.RawMessage(`{"test":2,"key":"value"}`),
+			},
+			expectError: "invalid first party data ext",
+		},
+	}
+
+	for _, test := range testCases {
+		t.Run(test.description, func(t *testing.T) {
+			resultDevice, err := resolveDevice(test.fpdConfig, test.bidRequestDevice)
+
+			if len(test.expectError) > 0 {
+				assert.EqualError(t, err, test.expectError)
+			} else {
+				assert.NoError(t, err)
+				assert.Equal(t, test.expectedDevice, resultDevice, "Result device is incorrect")
+			}
+		})
+	}
+}
+
 func TestBuildExtData(t *testing.T) {
 	testCases := []struct {
 		description string

firstpartydata/tests/extractbidderconfigfpd/bidder-config-device-data.json

@@ -0,0 +1,48 @@
+{
+  "description": "Extracts bidder configs for a bidder, handling device data",
+  "inputRequestData": {
+    "data": {},
+    "bidderconfig": [
+      {
+        "bidders": [
+          "appnexus"
+        ],
+        "config": {
+          "ortb2": {
+            "device": {
+              "ext": {
+                "wurfl": {
+                  "is_mobile": true,
+                  "complete_device_name": "Google Nexus 5",
+                  "form_factor": "Feature Phone",
+                  "model_name": "Nexus 5",
+                  "brand_name": "Google"
+                }
+              },
+              "make": "Google",
+              "model": "Nexus 5"
+            }
+          }
+        }
+      }
+    ]
+  },
+  "outputRequestData": {},
+  "bidderConfigFPD": {
+    "appnexus": {
+      "device": {
+        "ext": {
+          "wurfl": {
+            "is_mobile": true,
+            "complete_device_name": "Google Nexus 5",
+            "form_factor": "Feature Phone",
+            "model_name": "Nexus 5",
+            "brand_name": "Google"
+          }
+        },
+        "make": "Google",
+        "model": "Nexus 5"
+      }
+    }
+  }
+}

firstpartydata/tests/resolvefpd/bidder-fpd-only-device.json

@@ -0,0 +1,46 @@
+{
+  "description": "Bidder FPD defined only for device",
+  "inputRequestData": {
+    "device": {
+      "make": "reqMake",
+      "model": "reqModel"
+    }
+  },
+  "biddersWithGlobalFPD": [
+    "appnexus"
+  ],
+  "bidderConfigFPD": {
+    "appnexus": {
+      "device": {
+        "ext": {
+          "wurfl": {
+            "is_mobile": true,
+            "complete_device_name": "Google Nexus 5",
+            "form_factor": "Feature Phone",
+            "model_name": "Nexus 5",
+            "brand_name": "Google"
+          }
+        },
+        "make": "Google",
+        "model": "Nexus 5"
+      }
+    }
+  },
+  "outputRequestData": {
+    "appnexus": {
+      "device": {
+        "ext": {
+          "wurfl": {
+            "is_mobile": true,
+            "complete_device_name": "Google Nexus 5",
+            "form_factor": "Feature Phone",
+            "model_name": "Nexus 5",
+            "brand_name": "Google"
+          }
+        },
+        "make": "Google",
+        "model": "Nexus 5"
+      }
+    }
+  }
+}

openrtb_ext/request.go

@@ -118,10 +118,11 @@ type Config struct {
 	ORTB2 *ORTB2 `json:"ortb2,omitempty"`
 }
 
-type ORTB2 struct { //First party data
-	Site json.RawMessage `json:"site,omitempty"`
-	App  json.RawMessage `json:"app,omitempty"`
-	User json.RawMessage `json:"user,omitempty"`
+type ORTB2 struct { // First party data
+	Site   json.RawMessage `json:"site,omitempty"`
+	App    json.RawMessage `json:"app,omitempty"`
+	User   json.RawMessage `json:"user,omitempty"`
+	Device json.RawMessage `json:"device,omitempty"`
 }
 
 type ExtRequestCurrency struct {

openrtb_ext/request_test.go

@@ -279,6 +279,10 @@ func TestCloneExtRequestPrebid(t *testing.T) {
 						Bidders: []string{"foo"},
 						Config:  &Config{&ORTB2{User: json.RawMessage(`{"value":"config3"}`)}},
 					},
+					{
+						Bidders: []string{"Bidder9"},
+						Config:  &Config{&ORTB2{Device: json.RawMessage(`{"value":"config4"}`)}},
+					},
 				},
 			},
 			prebidCopy: &ExtRequestPrebid{
@@ -295,6 +299,10 @@ func TestCloneExtRequestPrebid(t *testing.T) {
 						Bidders: []string{"foo"},
 						Config:  &Config{&ORTB2{User: json.RawMessage(`{"value":"config3"}`)}},
 					},
+					{
+						Bidders: []string{"Bidder9"},
+						Config:  &Config{&ORTB2{Device: json.RawMessage(`{"value":"config4"}`)}},
+					},
 				},
 			},
 			mutator: func(t *testing.T, prebid *ExtRequestPrebid) {
@@ -304,6 +312,7 @@ func TestCloneExtRequestPrebid(t *testing.T) {
 					Config:  &Config{nil},
 				}
 				prebid.BidderConfigs[2].Config.ORTB2.User = json.RawMessage(`{"id": 345}`)
+				prebid.BidderConfigs[3].Config.ORTB2.Device = json.RawMessage(`{"id": 999}`)
 				prebid.BidderConfigs = append(prebid.BidderConfigs, BidderConfig{
 					Bidders: []string{"bidder2"},
 					Config:  &Config{&ORTB2{}},