How to Sign Apps
WizarPOS sign necessity
Basically, In Android system, all the application should be signed before installed to terminal. The key used to sign APK is the private key of a RSA key pair in a key store. So in the key store, there is a key pair (private key/ public key) and the public key's certificate. Please refer to Google's resource for detail. In the signed APK, the certificate relevant to the signing private key is included in the package. WizarPOS terminals are based on Android System. There are two mode of terminal:
- Production/User mode terminal
In the production terminal, the public key of the signing private key of the APK will be checked, it should be issued by the app root public key. By default, there is default WizarPOS root public key in the terminal. So you can request production public key to us for your key store (which will be used to sign APK). The applying step is describe in the document wizarPOSDevCertificateApplyGuide_en.pdf. After get the response certificate file from us, you should import the certificate file to your key store, then all the APK signed by this key store can be installed to production terminal.
- Developing/Engineer mode terminal
The developing terminal do not check public key. It's for the developer to debug their app, so it has USB connection and can use ADB debug.
Please notice, because of this difference, if your developing terminal switch to production terminal, all the application you installed in terminal, which is also not signed by above key store, will be removed automatically. Of cause, the default WizarPOS root public key can be updated to terminal owner's root public key in future. So the terminal owner can control their APK certificate by themselves.
How to sign app
Sign in an application project
Please refer to Google Sign APP
Sign an APK
WizarPOS provide a signature tool, it is a tool running in PC, and help the developer to sign their APK. Please download the signature tool. Before running it, please make sure that you have installed the JDK operation environment in your PC.
Run signature tool
In PC, run the follow command:
java -jar SignatureTools.jar sign [--keytype jks|pk8] [--apk <FILE>] [--out <FILE>] [--keystore <FILE.jks>] [--alias <String>] [--keyfile <FILE.pk8>] [--certs <FILE>] [--storepass <String>] [--keypass <String>]
SignatureTools.jar is the signature tool. The following table shows the parameters and their illustrations.
| Parameter | Value | Specification |
|---|---|---|
| --keytype | Jks or pk8 | The store path of the jks file or pk8 file |
| --apk | The file path of the apk before signed | The file path of the apk before signed |
| --out | The file path of the apk after signed | The file path of the apk after signed |
| --keystore | The file path of the jks file | When keytype is jks, this must be assigned |
| --alias | Alias name of private key | Alias name of private key in jks file |
| --keyfile | The file path of the pk8 file | When keytype is pk8, this is the private key file path |
| --certs | Certificates file path | When keytype is pk8, this is the certificate chain |
| --storepass | Password of keystore file | Password of keystore file |
| --keypass | password of private key | password of private key in jks file or pk8 file |