Yieldlab: Add Digital Service Act (DSA) handling

adapters/yieldlab/types.go

@@ -1,18 +1,60 @@
 package yieldlab
 
 import (
+	"github.com/prebid/prebid-server/v2/openrtb_ext"
 	"strconv"
 	"time"
 )
 
 type bidResponse struct {
-	ID         uint64 `json:"id"`
-	Price      uint   `json:"price"`
-	Advertiser string `json:"advertiser"`
-	Adsize     string `json:"adsize"`
-	Pid        uint64 `json:"pid"`
-	Did        uint64 `json:"did"`
-	Pvid       string `json:"pvid"`
+	ID         uint64       `json:"id"`
+	Price      uint         `json:"price"`
+	Advertiser string       `json:"advertiser"`
+	Adsize     string       `json:"adsize"`
+	Pid        uint64       `json:"pid"`
+	Did        uint64       `json:"did"`
+	Pvid       string       `json:"pvid"`
+	DSA        *dsaResponse `json:"dsa,omitempty"`
+}
+
+// dsaResponse defines Digital Service Act (DSA) parameters from Yieldlab yieldprobe response.
+type dsaResponse struct {
+	Behalf       string            `json:"behalf,omitempty"`
+	Paid         string            `json:"paid,omitempty"`
+	Adrender     *int              `json:"adrender,omitempty"`
+	Transparency []dsaTransparency `json:"transparency,omitempty"`
+}
+
+// openRTBExtRegsWithDSA defines the contract for bidrequest.regs.ext with the missing DSA property.
+//
+// The openrtb_ext.ExtRegs needs to be extended on yieldlab adapter level until DSA has been implemented
+// by the prebid server team (https://github.com/prebid/prebid-server/issues/3424).
+type openRTBExtRegsWithDSA struct {
+	openrtb_ext.ExtRegs
+	DSA *dsaRequest `json:"dsa,omitempty"`
+}
+
+// responseExtWithDSA defines seatbid.bid.ext with the DSA object.
+type responseExtWithDSA struct {
+	DSA dsaResponse `json:"dsa"`
+}
+
+// dsaRequest defines Digital Service Act (DSA) parameter
+// as specified by the OpenRTB 2.X DSA Transparency community extension.
+//
+// Should rather come from openrtb_ext package but will be defined here until DSA has been
+// implemented by the prebid server team (https://github.com/prebid/prebid-server/issues/3424).
+type dsaRequest struct {
+	Required     *int              `json:"dsarequired"`
+	PubRender    *int              `json:"pubrender"`
+	DataToPub    *int              `json:"datatopub"`
+	Transparency []dsaTransparency `json:"transparency"`
+}
+
+// dsaTransparency Digital Service Act (DSA) transparency object
+type dsaTransparency struct {
+	Domain string `json:"domain,omitempty"`
+	Params []int  `json:"dsaparams,omitempty"`
 }
 
 type cacheBuster func() string

adapters/yieldlab/yieldlab.go

@@ -96,11 +96,94 @@ func (a *YieldlabAdapter) makeEndpointURL(req *openrtb2.BidRequest, params *open
 		}
 	}
 
+	dsa, err := getDSA(req)
+	if err != nil {
+		return "", err
+	}
+	if dsa != nil {
+		if dsa.Required != nil {
+			q.Set("dsarequired", strconv.Itoa(*dsa.Required))
+		}
+		if dsa.PubRender != nil {
+			q.Set("dsapubrender", strconv.Itoa(*dsa.PubRender))
+		}
+		if dsa.DataToPub != nil {
+			q.Set("dsadatatopub", strconv.Itoa(*dsa.DataToPub))
+		}
+		if len(dsa.Transparency) != 0 {
+			transparencyParam := makeDSATransparencyURLParam(dsa.Transparency)
+			if len(transparencyParam) != 0 {
+				q.Set("dsatransparency", transparencyParam)
+			}
+		}
+	}
+
 	uri.RawQuery = q.Encode()
 
 	return uri.String(), nil
 }
 
+// getDSA extracts the Digital Service Act (DSA) properties from the request.
+func getDSA(req *openrtb2.BidRequest) (*dsaRequest, error) {
+	if req.Regs == nil || req.Regs.Ext == nil {
+		return nil, nil
+	}
+
+	var extRegs openRTBExtRegsWithDSA
+	err := json.Unmarshal(req.Regs.Ext, &extRegs)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse Regs.Ext object from Yieldlab response: %v", err)
+	}
+
+	return extRegs.DSA, nil
+}
+
+// makeDSATransparencyURLParam creates the transparency url parameter
+// as specified by the OpenRTB 2.X DSA Transparency community extension.
+//
+// Example result: platform1domain.com~1~~SSP2domain.com~1_2
+func makeDSATransparencyURLParam(transparencyObjects []dsaTransparency) string {
+	valueSeparator, itemSeparator, objectSeparator := "_", "~", "~~"
+
+	var b strings.Builder
+
+	concatParams := func(params []int) {
+		b.WriteString(strconv.Itoa(params[0]))
+		for _, param := range params[1:] {
+			b.WriteString(valueSeparator)
+			b.WriteString(strconv.Itoa(param))
+		}
+	}
+
+	concatTransparency := func(object dsaTransparency) {
+		if len(object.Domain) == 0 {
+			return
+		}
+
+		b.WriteString(object.Domain)
+		if len(object.Params) != 0 {
+			b.WriteString(itemSeparator)
+			concatParams(object.Params)
+		}
+	}
+
+	concatTransparencies := func(objects []dsaTransparency) {
+		if len(objects) == 0 {
+			return
+		}
+
+		concatTransparency(objects[0])
+		for _, obj := range objects[1:] {
+			b.WriteString(objectSeparator)
+			concatTransparency(obj)
+		}
+	}
+
+	concatTransparencies(transparencyObjects)
+
+	return b.String()
+}
+
 func (a *YieldlabAdapter) makeFormats(req *openrtb2.BidRequest) (bool, string) {
 	var formats []string
 	const sizesSeparator, adslotSizesSeparator = "|", ","
@@ -253,6 +336,7 @@ func (a *YieldlabAdapter) MakeBids(internalRequest *openrtb2.BidRequest, externa
 		}
 	}
 
+	var bidErrors []error
 	for _, bid := range bids {
 		width, height, err := splitSize(bid.Adsize)
 		if err != nil {
@@ -269,7 +353,13 @@ func (a *YieldlabAdapter) MakeBids(internalRequest *openrtb2.BidRequest, externa
 		if imp, exists := adslotToImpMap[strconv.FormatUint(bid.ID, 10)]; !exists {
 			continue
 		} else {
-			var bidType openrtb_ext.BidType
+			extJson, err := makeResponseExt(bid)
+			if err != nil {
+				bidErrors = append(bidErrors, err)
+				// skip as bids with missing ext.dsa will be discarded anyway
+				continue
+			}
+
 			responseBid := &openrtb2.Bid{
 				ID:     strconv.FormatUint(bid.ID, 10),
 				Price:  float64(bid.Price) / 100,
@@ -278,8 +368,10 @@ func (a *YieldlabAdapter) MakeBids(internalRequest *openrtb2.BidRequest, externa
 				DealID: strconv.FormatUint(bid.Pid, 10),
 				W:      int64(width),
 				H:      int64(height),
+				Ext:    extJson,
 			}
 
+			var bidType openrtb_ext.BidType
 			if imp.Video != nil {
 				bidType = openrtb_ext.BidTypeVideo
 				responseBid.NURL = a.makeAdSourceURL(internalRequest, req, bid)
@@ -299,7 +391,18 @@ func (a *YieldlabAdapter) MakeBids(internalRequest *openrtb2.BidRequest, externa
 		}
 	}
 
-	return bidderResponse, nil
+	return bidderResponse, bidErrors
+}
+
+func makeResponseExt(bid *bidResponse) (json.RawMessage, error) {
+	if bid.DSA != nil {
+		extJson, err := json.Marshal(responseExtWithDSA{*bid.DSA})
+		if err != nil {
+			return nil, fmt.Errorf("failed to make JSON for seatbid.bid.ext for adslotID %v. This is most likely a programming issue", bid.ID)
+		}
+		return extJson, nil
+	}
+	return nil, nil
 }
 
 func (a *YieldlabAdapter) findBidReq(adslotID uint64, params []*openrtb_ext.ExtImpYieldlab) *openrtb_ext.ExtImpYieldlab {

adapters/yieldlab/yieldlab_test.go

@@ -257,6 +257,98 @@ func Test_makeSupplyChain(t *testing.T) {
 	}
 }
 
+func Test_makeDSATransparencyUrlParam(t *testing.T) {
+	tests := []struct {
+		name           string
+		transparencies []dsaTransparency
+		expected       string
+	}{
+		{
+			name:           "No transparency objects",
+			transparencies: []dsaTransparency{},
+			expected:       "",
+		},
+		{
+			name:           "Nil transparency",
+			transparencies: nil,
+			expected:       "",
+		},
+		{
+			name: "Params without a domain",
+			transparencies: []dsaTransparency{
+				{
+					Params: []int{1, 2},
+				},
+			},
+			expected: "",
+		},
+		{
+			name: "Params without a params",
+			transparencies: []dsaTransparency{
+				{
+					Domain: "domain.com",
+				},
+			},
+			expected: "domain.com",
+		},
+		{
+			name: "One object; No Params",
+			transparencies: []dsaTransparency{
+				{
+					Domain: "domain.com",
+					Params: []int{},
+				},
+			},
+			expected: "domain.com",
+		},
+		{
+			name: "One object; One Param",
+			transparencies: []dsaTransparency{
+				{
+					Domain: "domain.com",
+					Params: []int{1},
+				},
+			},
+			expected: "domain.com~1",
+		},
+		{
+			name: "Three domain objects",
+			transparencies: []dsaTransparency{
+				{
+					Domain: "domain1.com",
+					Params: []int{1, 2},
+				},
+				{
+					Domain: "domain2.com",
+					Params: []int{3, 4},
+				},
+				{
+					Domain: "domain3.com",
+					Params: []int{5, 6},
+				},
+			},
+			expected: "domain1.com~1_2~~domain2.com~3_4~~domain3.com~5_6",
+		},
+	}
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			actual := makeDSATransparencyURLParam(test.transparencies)
+			assert.Equal(t, test.expected, actual)
+		})
+	}
+}
+
+func Test_getDSA_invalidRequestExt(t *testing.T) {
+	req := &openrtb2.BidRequest{
+		Regs: &openrtb2.Regs{Ext: json.RawMessage(`{"DSA":"wrongValueType"}`)},
+	}
+
+	dsa, err := getDSA(req)
+
+	assert.NotNil(t, err)
+	assert.Nil(t, dsa)
+}
+
 func TestYieldlabAdapter_makeEndpointURL_invalidEndpoint(t *testing.T) {
 	bidder, buildErr := Builder(openrtb_ext.BidderYieldlab, config.Adapter{
 		Endpoint: "test$:/something§"}, config.Server{ExternalUrl: "http://hosturl.com", GvlID: 1, DataCenter: "2"})