Paytm Payment Gateway flow and how it work :-

Android Configurations

1. Obtain the following

• download PGSDK library from https://github.com/Paytm-Payments/Paytm_Web_Sample_Kit_Java

• Client-side certificate (Optional: provide by PAYTM Web )
• Password for the Client side certificate. (Optional: provided by PAYTM Web)

                Add Client-side certificate file inside the raw folder. If the raw folder is not there then create the raw folder within the “res” folder.

• Add the INTERNET and ACCESS_NETWORK_STATE permissions to your AndroidManifest.xml. These two permissions are required for PGSDK Service to run.

• Add the Declaration of PaytmPGActivity in your AndroidManifest.xml. This activity is present in the PGSDK. Make sure that your manifest file also specifies this Activity element.

Once you have completed the above configuration setup, then you can start using PG Service API’s.

• How to use APIs

• Payment Transaction

  1. Obtain the PaytmPGService instance. Either obtain Staging service or obtain Production service depending on your need. PaytmPGService.getStagingService() will return the Service Object pointing to Staging Environment. PaytmPGService.getProductionService() will return the Service Object pointing to Production Environment.
  2. Create PaytmOrder Object holding the Order Information. The syntax for creating PaytmOrder Object is as follows:

  Java

  PaytmOrder Order = new PaytmOrder(Map <String, String> paramMap);

  1	PaytmOrder Order = new PaytmOrder(Map <String, String> paramMap);

  Where,
  paramMap is the map containing request parameter names and their respective values. Please refer Example given in the next subsection.

  3. Create PaytmMerchant Object holding the Merchant Configuration. The syntax for creating PaytmMerchant Object is as follows:

  Java     

  PaytmMerchant Merchant = new PaytmMerchant( "http://hostname/<checksum-gerneration-URL>", " http://hostname/<checksum-verification-URL>")

  1	PaytmMerchant Merchant = new PaytmMerchant( "http://hostname/<checksum-gerneration-URL>", " http://hostname/<checksum-verification-URL>")

  4. Create PaytmClient Object holding the Merchant Configuration. The syntax for creating PaytmMerchant Object is as follows:

  Java

  PaytmClientCertificate Certificate = new PaytmClientCertificate(String, String inFileName);

  1	PaytmClientCertificate Certificate  = new PaytmClientCertificate(String, String inFileName);

  where,
  inPassword is the Client side certificate password
  inFileName is the Client side certificate file name. This file must be present inside “raw” folder.

  5. Call the initialize() method to set PaytmOrder, PaytmMerchant and PaytmClientCertificate Objects. Method Signature is as follows:

  Java

  void com.paytm.pgsdk.PaytmPGService.initialize(PaytmOrder inOrder, PaytmMerchant inMerchant, PaytmClientCertificate inCertificate);

  1	void com.paytm.pgsdk.PaytmPGService.initialize(PaytmOrder inOrder, PaytmMerchant inMerchant, PaytmClientCertificate inCertificate);

  Where,
  inOrder is the Object which is holding Order Information.
  inMerchant is the Object which is holding Merchant Configuration.
  inCertificate is the Object which is holding Certificate Information. Pass this as null if no client certificate is used by the merchant (as given above in the Prerequisites section)

  6. Call startPaymentTransaction() method to start the Payment Transaction. Method Signature is as follows:

  Java

  void com.paytm.pgsdk.PaytmPGService.startPaymentTransaction(Context inCtxt, boolean inbHideHeader, boolean inbSendAllChecksumResponseParametersToPGServer, PaytmPaymentTransactionCallback inPaymentTransactionCallback);

  1	void com.paytm.pgsdk.PaytmPGService.startPaymentTransaction(Context inCtxt, boolean inbHideHeader, boolean inbSendAllChecksumResponseParametersToPGServer, PaytmPaymentTransactionCallback inPaymentTransactionCallback);

  Where,
  inCtxt is the Activity Context in which you are calling this method.
  inbHideHeader is a boolean variable to hide or show Header Bar.
  inbSendAllChecksumResponseParametersToPGServer is a boolean variable to determine whether to send all checksum response parameters to PG Server or not.
  inPaymentTransactionCallback is a PaytmPaymentTransactionCallback instance to send callback messages back to merchant application.

  Once Payment Transaction is done or some error occurs then the callback methods of
  PaytmPaymentTransactionCallback will be called with a successful response or an error message.

• Example