Flutter Android: Unable to fetch in-app products from Google Play

Question

I'm currently facing an issue where my Flutter application is unable to fetch consumable in-app products from Google Play store. However, my application is able to fetch all products from the Apple app store.

I can't identify what step I'm missing or what is causing all of my product ids to be not found. I'm using flutter's in_app_purchase module to facilitate in app purchases.

For Android, here are the setup steps I've taken.

1. I've setup my Google Play Console and Developer Account
2. Completed all the tasks in the Set up your app section
3. Generated a keystore file to sign my app keytool -genkey -v -keystore c:\Users\USER_NAME\key.jks -storetype JKS -keyalg RSA -keysize 2048 -validity 10000 -alias key
4. Created a file named /android/key.properties that contains a reference to my keystore file. The contents of this file look like the following:

storePassword=<password from previous step>
keyPassword=<password from previous step>
keyAlias=key
storeFile=<location of the key store file, such as /Users/<user name>/key.jks>

5. Configured my build.gradle file to include the following

def keystoreProperties = new Properties()
def keystorePropertiesFile = rootProject.file('key.properties')
if (keystorePropertiesFile.exists()) {
   keystoreProperties.load(new FileInputStream(keystorePropertiesFile))
}
android {
   signingConfigs {
       release {
           keyAlias keystoreProperties['keyAlias']
           keyPassword keystoreProperties['keyPassword']
           storeFile keystoreProperties['storeFile'] ? file(keystoreProperties['storeFile']) : null
           storePassword keystoreProperties['storePassword']
       }
   }
   buildTypes {
       release {
           signingConfig signingConfigs.release
       }
   }
}

6. Created a app bundle and published it under the closed track flutter build appbundle --flavor prod --release. I also let google sign my app "Google signing the app" when I was uploading the artifact.

7. I've added a tester that is not associated with the developer account and added the same email under "License testing" with the License response "RESPOND_NORMALLY".

8. I've also created three consumable products and set them to active.

The following shows my code that fetches products

  List<String> _kProductIds = <String>[
    'my_app_premium_year_c',
    'my_app_premium_month_c',
    'my_app_premium_week_c'
  ];
final ProductDetailsResponse productResponse =
        await InAppPurchase.instance.queryProductDetails(_kProductIds.toSet());

The following shows the unexpected results I'm getting. That is all of my products are in the notFoundIDs list. [my_app_premium_year_c, my_app_premium_month_c, my_app_premium_week_c]

I expect the notFoundIDs list to be empty when including the following code print("ProductIDs not found: ${productResponse.notFoundIDs}");

Any hints or suggestions would be much appreciated.

EDIT: The following screenshot shows my in-app products page on the google console. I've covered up certain identifiers to protect my privacy, however the product ids in the screenshot match the product ids in my code.

The following screenshot shows my app published under the alpha, closed track.

Clunk

is your productid name correct? what about a screenshot – Thai

Yes it's correct. It matches exactly for all three products. – Clunk

could you please provide some screenshots of google console – Thai

@Thai Updated with a screenshot. – Clunk

My app isn't even able to find the product with ID android.test.purchased. Isn't this product automatically configured and available? – Clunk

hmm could you please use network tools to examine the network traffic? (even if you use https there are some tools to decrypt it; or intercept the flutter HttpClient etc). Please paste the raw network traffic (possibly HTTP request and response) here to see what is indeed sent to google – Thai

Does it matter that the in app products were created before the first bundle was uploaded to the test track? – Clunk

I am not sure. Why I talk about network traffic is that, you are using a wrapped API (the InAppPurchase), which can have subtle bugs. So we need to examine the raw data (raw HTTP request) that sends to google – Thai

Ok makes sense. Always the chance for bugs but it might be important to know it's a first party library, officially supported by Flutter. Anyway, I was able to collect quite a few packets sent between google play and my app via wireshark. I've saved the packets using the DNS protocol and the subsequent packets using QUIC protocol. I'm not sure how to extract much information out of these packets though. – Clunk

Well it should be HTTP/HTTPS. Search about it - how to extract https – Thai

Check this might help. #16548484! – Melvinmelvina

Answer 1

The issue has finally been solved. You need to call InAppPurchase method, isAvailable(), before queryProductDetails() when on the Android platform. I'm not sure why you don't need to do the same when on the IOS platform.

The documentation didn't specify the need for this outright, but let it stand that querying for products AFTER checking if the store is available fixed my issue on Android.

Clunk