Assinatura de cliques para ad networks

Exemplo de URL de clique do OneLink (multiplataforma):

https://yourbrand.onelink.me/qsWL?pid=mediasource_int&advertising_id=12345678-1234-1234-1234-123456789012
&af_ad_type=video&af_adset=MMP&clickid=sdkfjasksjskdfj9845weh&af_siteid=my_site&af_viewthrough_lookback=2h&c=my_campaign
&expires=1689695615

Exemplo de objeto json para assinatura (antes de remover espaços em branco):

[
	["link_domain","yourbrand.onelink.me"],
	["link_path","qswl"],
	["pid","mediasource_int"],
	["af_siteid","my_site"],
	["clickid","12345"],
	["expires","1689695615"]
]

Exemplo de objeto json para assinatura (após remover espaços em branco)

[["link_domain","yourbrand.onelink.me"],["link_path","qswl"],["pid","mediasource_int"],["template-id","qswl"],["af_siteid","my_site"],["clickid","12345"],["expires","1689695615"]]

URL do clique final com a assinatura:

https://yourbrand.onelink.me/qsWL?pid=mediasource_int&advertising_id=12345678-1234-1234-1234-123456789012
&af_ad_type=video&af_adset=MMP&af_siteid=my_site&af_viewthrough_lookback=2h&c=my_campaign
&expires=1689695615
&signature_v2=WIfCmfLAPSsVrBTqCqfihMeLCnbE4dIAlhHF84WsiWA

[
  {"index":1, "name":"pid", "mandatory":true},
  {"index":2, "name":"af_prt", "mandatory":false},
  {"index":3, "name":"af_siteid", "mandatory":true},
  {"index":4, "name":"clickid", "mandatory":true},
  {"index":5, "name":"expires", "mandatory":true},
  {"index":6, "name":"af_engagement_type", "mandatory":false},
  {"index":7, "name":"af_click_lookback", "mandatory":false},
  {"index":8, "name":"af_viewthrough_lookback", "mandatory":false},
  {"index":9, "name":"af_reengagement_window", "mandatory":false},
  {"index":10, "name":"is_retargeting", "mandatory":false},
  {"index":11, "name":"af_ip", "mandatory":false},
  {"index":12, "name":"advertising_id", "mandatory":false},
  {"index":13, "name":"oaid", "mandatory":false},
  {"index":14, "name":"fire_advertising_id", "mandatory":false},
  {"index":15, "name":"idfa", "mandatory":false},
  {"index":16, "name":"idfv", "mandatory":false}
]

package main

import (
	"crypto/hmac"
	"crypto/sha256"
	"encoding/base64"
	"encoding/json"
	"errors"
	"fmt"
	"io"
	"net/url"
	"os"
	"strings"
	"time"
)

type Param struct {
	Name      string
	Mandatory bool
}

func LoadSupportedParams() ([]Param, error) {
	path := "./signing-supported-params.json"
	jsonFile, _ := os.Open(path)
	defer jsonFile.Close()
	byteValue, err := io.ReadAll(jsonFile)
	if err != nil {
		return nil, errors.New("failed loading " + path)
	}
	var params []Param
	_ = json.Unmarshal(byteValue, &params)
	return params, nil
}

func computeHmac256(message, secret string) (res string, errResult error) {
	defer func() {
		if r := recover(); r != nil {
			errResult = r.(error)
			fmt.Println("failed to invoke ComputeHmac256. err: %+v", errResult)
			res = ""
			return
		}
	}()

	key := []byte(secret)
	h := hmac.New(sha256.New, key)
	h.Write([]byte(message))
	return base64.URLEncoding.WithPadding(base64.NoPadding).EncodeToString(h.Sum(nil)), nil
}

// this function accepts a click url, a ttl for the click in seconds, and the list of supported params
// the function:
// 1. adds the expiration to the click based on the provided ttl
// 2. builds a json for the signature
// 3. create an HMAC256 signature
// 4. adds the signature to the click url
func signURLV2(originalURL string, secret string, clickTtlSeconds int64, supportedParams []Param) (signedURL string, err error) {

	//add an expiration to the click
	expires := time.Now().UTC().Unix() + clickTtlSeconds
	urlWithExpired := fmt.Sprintf("%s%s%d", originalURL, "&expires=", expires)

	//parse the url
	parsedURL, err := url.Parse(urlWithExpired)
	if err != nil {
		return "", errors.New("failed parsing URL")
	}

	//build a json from the url
	jsonStr, err := buildJSONFromURLV2(parsedURL, supportedParams)
	if err != nil {
		return "", err
	}

	//create a signature
	signatureV2, err := computeHmac256(jsonStr, secret)
	if err != nil {
		fmt.Println("Failed to computeHMAC256 for url %s. err: %+v", jsonStr, err)
		return "", errors.New("fail to computeHMAC256 for url")
	}

	//add the signature to the url
	signedURL = fmt.Sprintf("%s%s%s", urlWithExpired, "&signature_v2=", signatureV2)

	return signedURL, nil

}

// this function builds a json from a given click url.
// It returns a string representation of the json ready to be signed.
func buildJSONFromURLV2(parsedURL *url.URL, supportedParams []Param) (string, error) {
	//initiate an empty json in the structure [[key-1,val-1],[key-2,val-2]...[key-n,val-n]]
	var jsonData [][2]string

	//add the url host domain to the json
	domain := parsedURL.Host
	param := [2]string{"link_domain", domain}
	jsonData = append(jsonData, param)

	//add the path (app-id or template-id) to the json
	path := parsedURL.Path
	if len(path) > 1 {
		param := [2]string{"link_path", path[1:]}
		jsonData = append(jsonData, param)
	}

	//loop over the ordered list of supported parameters and add them to the json
	for i := 0; i <len(supportedParams); i++ {name := supportedParams[i].Name val := parsedURL.Query().Get(name) if len(val) > 0 {
			param := [2]string{name, val}
			jsonData = append(jsonData, param)
		} else if supportedParams[i].Mandatory {
			return "", errors.New("missing mandatory param: " + name)
		}
	}

	//generate string representation of the json object
	jsonObj, _ := json.Marshal(jsonData)
	return strings.ToLower(string(jsonObj)), nil
}

func main() {

	supportedParams, err := LoadSupportedParams()
	if err != nil {
		fmt.Println("Error: ", err)
		os.Exit(1)
	}

	var secretKey = "tqJU4Qd/eFTEWfqW7KCG9asDO0bmZoFzv8GY3VPSPAM="
	var clickTtlSeconds int64 = 60
	var originalUrl = "https://yourbrand.onelink.me/qsWL?pid=mediasource_int&advertising_id=12345678-1234-1234-1234-123456789012&clickid=1234&af_ad_type=video&af_adset=MMP&af_siteid=my_site&af_viewthrough_lookback=2h&c=my_campaign"

	fmt.Println("Original URL: ", originalUrl)

	signedUrl, err := signURLV2(originalUrl, secretKey, clickTtlSeconds, supportedParams)
	if err != nil {
		fmt.Println("Error: ", err)
		os.Exit(1)
	} else {
		fmt.Println("Signed URL: ", signedUrl)
	}
}

Método de geração de chave secreta

POST https://hq1.appsflyer.com/api/p360-click-signing/secret?ttlHours=<ttlHours>

curl --location --request POST 'https://hq1.appsflyer.com/api/p360-click-signing/secret?ttlHours=36' \
-H 'Authorization: Bearer {API V2.0 token available to the admin in the dashboard.}'

{
	"secret-key-id": "59ad6547-affc-45eb-a6c9-9805f88ee755",
	"secret-key": "zGW6Rhrmb8+vuhHtL/Kp6rW5Ci9PNsjH1J5MGO9SIeg=",
	"expiration": 1610533263
}

Método de revogação de chave secreta

DELETE https://hq1.appsflyer.com/api/p360-click-signing/secret/<secret-id>

curl --location --request DELETE 'https://hq1.appsflyer.com/api/p360-click-signing/secret/59ad6547-affc-45eb-a6c9-9805f88ee755' \
-H 'Authorization: Bearer {API V2.0 token available to the admin in the dashboard.}'

Método de teste

POST https://hq1.appsflyer.com/api/p360-click-signing/test

curl --location --request POST 'https://hq1.appsflyer.com/api/p360-click-signing/test' \
-H 'Authorization: Bearer {API V2.0 token available to the admin in the dashboard.}' \
--header 'Content-Type: application/json' \
--data-raw '{
   "url": "https://app.appsflyer.com/com.app.id?pid=adnetwork_int&c=my_campaign&clickid=sdkfjasksjskdfj9845weh&af_site_id=12345&expires=1597657118&signature=8fnDVzZP_WRZnv3KNJaREOEfvB5p9oRc_XlKEvUo8gk"
}'

{
	"test-status":"Passed / Failed",
	"message": "Invalid signature"
}

Método de modo de configuração

POST https://hq1.appsflyer.com/api/p360-click-signing/config/mode/<mode>

curl --location --request POST 'https://hq1.appsflyer.com/api/p360-click-signing/config/mode/report-only' \
-H 'Authorization: Bearer {API V2.0 token available to the admin in the dashboard.}'

Configurar método de interruptor

POST https://hq1.appsflyer.com/p360-click-signing/config/circuit-breaker

curl --location --request POST 'https://hq1.appsflyer.com/api/p360-click-signing/config/circuit-breaker' \
-H 'Authorization: Bearer {API V2.0 token available to the admin in the dashboard.}'
--data-raw '{
"status":"enabled"
}'

Obter método de configuração

GET https://hq1.appsflyer.com/api/p360-click-signing/config

curl --location --request GET 'https://hq1.appsflyer.com/api/p360-click-signing/config' \
-H 'Authorization: Bearer {API V2.0 token available to the admin in the dashboard.}'

{
	"mode": "report-only",
	"active-key-ids": [
		{
			"secret-key-id": "59ad6547-affc-45eb-a6c9-9805f88ee755",
			"expiration": 1610533263
		}
	],
	"excluded-app-ids": [
		"app-id-1", 	"app-id-2"
	]

}

Método de relatório

GET https://hq1.appsflyer.com/api/p360-click-signing/report

curl --location --request GET 'https://hq1.appsflyer.com/api/p360-click-signing/report?start-date=2021-01-07T07&end-date=2021-01-17T12' \
-H 'Authorization: Bearer {API V2.0 token available to the admin in the dashboard.}' \

Excluir método de aplicativo

POST https://hq1.appsflyer.com/api/p360-click-signing/config/excluded-app/<app-id>

curl --location --request POST 'https://hq1.appsflyer.com/api/p360-click-signing/config/excluded-app/appname.com' \
-H 'Authorization: Bearer {API V2.0 token available to the admin in the dashboard.}'

Remover método de aplicativo excluído

DELETE https://hq1.appsflyer.com/api/p360-click-signing/config/excluded-app/<app-id>

curl --location --request DELETE 'https://hq1.appsflyer.com/api/p360-click-signing/config/excluded-app/appname.com' \
-H 'Authorization: Bearer {API V2.0 token available to the admin in the dashboard.}'

package sign;

import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.util.Base64;

.
.
.

String clickUrl = "https://app.appsflyer.com/com.app.id?pid=adnetwork_int&c=my_campaign&clickid=sdkfjasksjskdfj9845weh&af_site_id=12345";
String secretKey = "secret_key"; 
int ttlMinutes = 5;


//add expiration to the click URL
long expiration = System.currentTimeMillis() + (60000L * ttlMinutes);
clickUrl += "&expires="+expiration;

//create a SecretKey object from the given key string
SecretKeySpec signingKey = new SecretKeySpec(secretKey.getBytes(), "HmacSHA256");
Mac mac = Mac.getInstance("HmacSHA256");
mac.init(signingKey);

//generate a signature from the click url and encode it with base64 without padding
String generatedSignature =     
Base64.getUrlEncoder().withoutPadding().encodeToString(mac.doFinal(clickUrl.getBytes()));

//add the signature to the click URL
String signedClickUrl = clickUrl + "&signature=" + generatedSignature;

A AppsFlyer interrompe a validação da assinatura de clique e retorna ao modo somente relatório quandomais de 90% dos cliques em uma hora falham na validação da assinatura.

Isso protege sua empresa de um possível problema técnico e permite que você encontre a causa da anomalia:

• Se você perceber que a assinatura está funcionando conforme o esperado e os cliques estão sendo bloqueados corretamente, desabilite o interruptor usando o método de configuração do interruptor.
• Se você perceber que os cliques estão sendo bloqueados incorretamente:
  1. Certifique-se de que você tem uma chave secreta válida verificando a configuração de assinatura de clique usando ométodo de configuração get.
  2. Use o relatório de assinatura de cliques para obter mais informações sobre os cliques bloqueados e investigar as fontes (IDs de agência/aplicativo) e os motivos dos cliques inválidos.
• Se você encontrar um problema com um aplicativo específico devido a uma integração fora do padrão, exclua esse aplicativo da validação de assinatura de cliques usando a API de exclusão de aplicativo.
• Se você encontrar um problema com sua configuração:
  1. Continue executando no modo somente relatório.
  2. Corrija o seu processo de assinatura de cliques.
  3. Verifiqueos resultados no relatório de assinatura de cliquesereative a validação de assinatura de cliques quando observar que os cliques estão sendo validados conforme o esperado.