Tuve problemas para manejar los mensajes de IPN de PayPal en la aplicación web que estoy desarrollando. Le pedí al servicio técnico de vendedores de PayPal información sobre el manejoReversed, Canceled_Reversed yRefunded Mensajes de IPN. Este código a continuación es lo que encontré útil de sus respuestas. Espero que también use otros:

Pago:

{
    "mc_gross":"5.00",
    "protection_eligibility":"Ineligible",
    "item_number1":"",
    "payer_id":"2LMAK5CCRFC7Y",
    "tax":"0.00",
    "payment_date":"15:51:55 May 02, 2014 PDT",
    "payment_status":"Completed",
    "charset":"windows-1252",
    "mc_shipping":"0.00",
    "mc_handling":"0.00",
    "first_name":"Roman",
    "mc_fee":"0.45",
    "notify_version":"3.8",
    "custom":"",
    "payer_status":"verified",
    "num_cart_items":"1",
    "mc_handling1":"0.00",
    "verify_sign":"AhKjPyUAFwaeM5vZHwjU.0caZhHtAV.H1ZruV63s-yLcAYfGQU8WYTEX",
    "payer_email":"XXXXXX",
    "mc_shipping1":"0.00",
    "tax1":"0.00",
    "txn_id":"64M28299HV0955007",
    "payment_type":"instant",
    "last_name":"Arora",
    "item_name1":"Air Pilots",
    "receiver_email":"XXXXXX",
    "payment_fee":"0.45",
    "quantity1":"1",
    "receiver_id":"XXXXXX",
    "txn_type":"cart",
    "mc_gross_1":"5.00",
    "mc_currency":"USD",
    "residence_country":"US",
    "transaction_subject":"Air Pilots",
    "payment_gross":"5.00",
    "ipn_track_id":"dfa90ecb35b46"
}

Cuando se presenta una disputa con el centro de resolución de PayPal: Este IPN tiene el mismo txn_id del pago inicial

{
    "txn_type":"new_case",
    "payment_date":"15:51:55 May 02, 2014 PDT",
    "case_id":"PP-003-125-383-356",
    "case_type":"dispute",
    "business":"XXXXXX",
    "verify_sign":"AbFfRIjxGf8ulMoIvA2Jhdo84gY5Ahewo.T-JjKYBzZxoAYuDLiZf5oK",
    "payer_email":"XXXXXX",
    "txn_id":"64M28299HV0955007",
    "case_creation_date":"14:46:47 May 05, 2014 PDT",
    "receiver_email":"XXXXXX",
    "payer_id":"2LMAK5CCRFC7Y",
    "receiver_id":"XXXXXX",
    "reason_code":"non_receipt",
    "custom":"","charset":"windows-1252",
    "notify_version":"3.8",
    "ipn_track_id":"6b3a7ef61a303"
}

Cantidad en espera (payment_status esReversed): El txn_id del pago inicial es parent_txn_id. Tiene un nuevo txn_id.

{
    "mc_gross":"-4.55",
    "protection_eligibility":"Ineligible",
    "item_number1":"",
    "payer_id":"2LMAK5CCRFC7Y",
    "payment_date":"14:47:45 May 05, 2014 PDT",
    "payment_status":"Reversed",
    "charset":"windows-1252",
    "mc_shipping":"0.00",
    "mc_handling":"0.00",
    "first_name":"Roman",
    "mc_fee":"-0.45",
    "notify_version":"3.8",
    "reason_code":"buyer_complaint",
    "custom":"",
    "business":"XXXXXX",
    "mc_handling1":"0.00",
    "verify_sign":"Aayt7rRv.9vczRke0KD5otSJgqTEA6ETzuIl3f7JWHiTh.q-Pp8Lh7QW",
    "payer_email":"XXXXXX",
    "mc_shipping1":"0.00",
    "tax1":"0.00",
    "parent_txn_id":"64M28299HV0955007",
    "txn_id":"4RW75981SW305352R",
    "payment_type":"instant",
    "last_name":"Arora",
    "item_name1":"Air Pilots",
    "receiver_email":"XXXXXX",
    "payment_fee":"-0.45",
    "quantity1":"1",
    "receiver_id":"XXXXXX",
    "mc_gross_1":"5.00",
    "mc_currency":"USD",
    "residence_country":"US",
    "transaction_subject":"Air Pilots",
    "payment_gross":"-4.55",
    "ipn_track_id":"ed496d8ef1d7d"
}

Cantidad liberada (payment_status esCanceled_Reversal) - El comerciante ganó la disputa: el txn_id del pago inicial es parent_txn_id. Tiene el mismo txn_id de IPN - Cantidad en espera.

{
    "mc_gross":"4.55",
    "protection_eligibility":"Ineligible",
    "item_number1":"",
    "payer_id":"2LMAK5CCRFC7Y",
    "payment_date":"14:47:45 May 05, 2014 PDT",
    "payment_status":"Canceled_Reversal",
    "charset":"windows-1252",
    "mc_shipping":"0.00",
    "mc_handling":"0.00",
    "first_name":"Roman",
    "mc_fee":"0.45",
    "notify_version":"3.8",
    "reason_code":"buyer_complaint",
    "custom":"",
    "business":"XXXXXX",
    "mc_handling1":"0.00",
    "verify_sign":"Auodxl0Yf.7io9Qqvln7PODrgOvjAbuOsf7PTpgdLQyLHk1uoYabZCsl",
    "payer_email":"XXXXXX",
    "mc_shipping1":"0.00",
    "tax1":"0.00",
    "parent_txn_id":"64M28299HV0955007",
    "txn_id":"4RW75981SW305352,R",
    "payment_type":"instant",
    "last_name":"Arora",
    "item_name1":"Air Pilots",
    "receiver_email":"XXXXXX",
    "payment_fee":"0.45",
    "quantity1":"1",
    "receiver_id":"XXXXXX",
    "mc_gross_1":"5.00",
    "mc_currency":"USD",
    "residence_country":"US",
    "transaction_subject":"Air Pilots",
    "payment_gross":"4.55",
    "ipn_track_id":"72b0067375b5f"
}

Inversión(payment_status esRefunded) - El comerciante perdió la disputa: el txn_id del pago inicial es parent_txn_id. Tiene nuevo txn_id.

{
    "mc_gross":"-5.00",
    "protection_eligibility":"Ineligible",
    "item_number1":"",
    "payer_id":"2LMAK5CCRFC7Y",
    "payment_date":"10:45:49 May 06, 2014 PDT",
    "payment_status":"Refunded",
    "charset":"windows-1252",
    "mc_shipping":"0.00",
    "mc_handling":"0.00",
    "first_name":"Roman",
    "mc_fee":"-0.15",
    "notify_version":"3.8",
    "reason_code":"refund",
    "custom":"",
    "business":"XXXXXX",
    "mc_handling1":"0.00",
    "verify_sign":"AmmJ3Da6WMy0qcyvYpAIcfVWfBEgAJfGvFm8TK2MGOZV6Hc9Ll5axN.V",
    "payer_email":"XXXXXX",
    "mc_shipping1":"0.00",
    "tax1":"0.00",
    "parent_txn_id":"64M28299HV0955007",
    "txn_id":"4CG08179BW957404H",
    "payment_type":"instant",
    "last_name":"Arora",
    "item_name1":"Air Pilots",
    "receiver_email":"XXXXXX",
    "payment_fee":"-0.15",
    "quantity1":"1",
    "receiver_id":"XXXXXX",
    "mc_gross_1":"5.00",
    "mc_currency":"USD",
    "residence_country":"US",
    "transaction_subject":"Air Pilots",
    "payment_gross":"-5.00",
    "ipn_track_id":"54a6104f4cebb"
}