signing certificate hash 값 얻기
Get your debug signing certificate hash
In the root of your Flutter app project, change directory to the android/ folder and generate a signing report:
cd android ./gradlew :app:signingReport
Note: In case the gradle wrapper file is not present, you can generate it by building your application for Android once by running flutter build appbundle.
You'll be presented with a large list of signing keys. Because you're looking for the hash for the debug certificate, look for the certificate with the Variant and Config properties set to debug. It's likely for the keystore to be in your home folder under .android/debug.keystore.
> Task :app:signingReport
Variant: debug
Config: debug
Store: /<USER_HOME_FOLDER>/.android/debug.keystore
Alias: AndroidDebugKey
MD5: XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX
SHA1: XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX
SHA-256: XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX
Valid until: Tuesday, January 19, 2038
signingReport 하면 release키도 설정되어있음 나옴..