delpay: introduced a new rpc method to delete a payment by hash

Changelog-Added: JSON-RPC: delpay a new method to delete the payment completed or failed.

doc/Makefile

@@ -16,6 +16,7 @@ MANPAGES := doc/lightning-cli.1 \
 	doc/lightning-decodepay.7 \
 	doc/lightning-delexpiredinvoice.7 \
 	doc/lightning-delinvoice.7 \
+	doc/lightning-delpay.7 \
 	doc/lightning-dev-sendcustommsg.7 \
 	doc/lightning-disconnect.7 \
 	doc/lightning-feerates.7 \

doc/index.rst

@@ -38,6 +38,7 @@ c-lightning Documentation
    lightning-decodepay <lightning-decodepay.7.md>
    lightning-delexpiredinvoice <lightning-delexpiredinvoice.7.md>
    lightning-delinvoice <lightning-delinvoice.7.md>
+   lightning-delpay <lightning-delpay.7.md>
    lightning-dev-sendcustommsg <lightning-dev-sendcustommsg.7.md>
    lightning-disconnect <lightning-disconnect.7.md>
    lightning-feerates <lightning-feerates.7.md>

doc/lightning-delpay.7.md

@@ -0,0 +1,58 @@
+lightning-delpay -- Command for removing a completed payment
+============================================================
+
+SYNOPSIS
+--------
+
+**delpay** *payment_hash* \[status\] (is not specify the status is complete)
+
+DESCRIPTION
+-----------
+
+The **delpay** RPC command removes a payment as given in **listsendpays** or **listpays** with a complete or failed
+status. However, the command doesn't permit to remove the pending payment.
+
+EXAMPLE JSON REQUEST
+------------
+```json
+{
+  "id": 82,
+  "method": "delpay",
+  "params": {
+    "payment_hash": "4fa2f1b001067ec06d7f95b8695b8acd9ef04c1b4d1110e3b94e1fa0687bb1e0",
+    "status": "complete"
+  }
+}
+```
+
+RETURN VALUE
+------------
+
+On success, the command will return a payment object, such as the listpays.
+
+On failure, an error is returned and any payment is deleted. If the lightning process fails before responding, the
+caller should use lightning-listsentpays(7) or lightning-listpays(7) to query whether this payment was deleted or not.
+
+The following error codes may occur:
+
+- -32602: Some parameter missed or some parameter is malformed;
+- -1: Payment with wrong status
+- -1: Payment not found.
+
+-
+AUTHOR
+------
+
+Vincenzo Palazzo <<vincenzopalazzodev@gmail.com>> is mainly responsible.
+
+SEE ALSO
+--------
+
+lightning-listpays(7), lightning-listsendpays(7),
+lightning-pay(7), lightning-paystatus(7),
+~~lightning-keysend(7)~~
+
+RESOURCES
+---------
+
+Main web site: <https://github.com/ElementsProject/lightning>

lightningd/pay.c

@@ -42,6 +42,31 @@ struct sendpay_command {
 	struct command *cmd;
 };
 
+static enum wallet_payment_status string_to_payment_status(const char *status_str)
+{
+	if (streq(status_str, "complete")) {
+		return PAYMENT_COMPLETE;
+	} else if (streq(status_str, "failed")) {
+		return PAYMENT_FAILED;
+	} else if (streq(status_str, "pending")) {
+		return PAYMENT_PENDING;
+	}
+	return -1;
+}
+
+static const char *payment_status_to_string(const enum wallet_payment_status status)
+{
+	switch (status) {
+	case PAYMENT_COMPLETE:
+		return "complete";
+	case PAYMENT_FAILED:
+		return "failed";
+	default:
+		return "pending";
+	}
+}
+
+
 static void destroy_sendpay_command(struct sendpay_command *pc)
 {
 	list_del(&pc->list);
@@ -1496,6 +1521,74 @@ static const struct json_command listsendpays_command = {
 };
 AUTODATA(json_command, &listsendpays_command);
 
+static struct command_result *json_delpay(struct command *cmd,
+						const char *buffer,
+						const jsmntok_t *obj UNNEEDED,
+						const jsmntok_t *params)
+{
+	struct json_stream *response;
+	const struct wallet_payment *payment;
+	const char *status_str;
+	enum wallet_payment_status status;
+	struct sha256 *payment_hash;
+    u64 *partid;
+
+	if (!param(cmd, buffer, params,
+		p_req("payment_hash", param_sha256, &payment_hash),
+		p_opt("status", param_string, &status_str),
+		p_opt_def("partid", param_u64, &partid, 0),
+		NULL))
+		return command_param_failed();
+
+	if (!payment_hash)
+		return command_fail(cmd, JSONRPC2_INVALID_PARAMS,
+						"missing required parameter: payment_hash");
+
+
+	status = status_str == NULL ? PAYMENT_COMPLETE : string_to_payment_status(status_str);
+
+	if (status == -1)
+		return command_fail(cmd, JSONRPC2_INVALID_PARAMS,
+						"status insert %s wrong", status_str);
+
+	if (status == PAYMENT_PENDING)
+		return command_fail(cmd, LIGHTNINGD, "invalid status: %s",
+							payment_status_to_string(status));
+
+	payment = wallet_payment_by_hash(cmd, cmd->ld->wallet, payment_hash, *partid);
+
+	//FIXME(vicenzopalazzo): set the correct error about payment not found
+	if (!payment)
+		return command_fail(cmd, LIGHTNINGD,
+			"unknown payment with payment_hash: %s and status: %s",
+				type_to_string(tmpctx, struct sha256, payment_hash),
+						payment_status_to_string(status));
+
+   	//FIXME(vicenzopalazzo) set the correct error about status
+	if (payment->status != status)
+		return command_fail(cmd, LIGHTNINGD,
+			"payment status is %s not %s",
+				payment_status_to_string(payment->status),
+					payment_status_to_string(status));
+
+	wallet_payment_delete(cmd->ld->wallet, payment_hash, payment->partid);
+
+	response = json_stream_success(cmd);
+	json_object_start(response, "payment");
+	json_add_payment_fields(response, payment);
+	json_object_end(response);
+
+	return command_success(cmd, response);
+}
+
+static const struct json_command delpay_command = {
+	"delpay",
+	"payment",
+	json_delpay,
+	"Delete payment with {payment_hash} and {status}, (if no is complete)",
+};
+AUTODATA(json_command, &delpay_command);
+
 static struct command_result *json_createonion(struct command *cmd,
 						const char *buffer,
 						const jsmntok_t *obj UNNEEDED,

tests/test_pay.py

@@ -3221,3 +3221,58 @@ def test_bolt11_null_after_pay(node_factory, bitcoind):
     pays = l2.rpc.listpays()["pays"]
     assert(pays[0]["bolt11"] == invl1)
     assert('amount_msat' in pays[0] and pays[0]['amount_msat'] == amt)
+
+
+def test_delpay_argument_invalid(node_factory):
+    """
+    This test includes all possible combination of input error inside the
+    delpay command.
+    TODO(vincenzopalazzo) more sanity test when the payment exists.
+    """
+
+    l1 = node_factory.get_node()
+
+    with pytest.raises(RpcError):
+        l1.rpc.delpay()
+
+    # invoice unpayed
+    payment_hash = l1.rpc.invoice(10**5, "no_payed", "Invoice unpayed")["payment_hash"]
+    with pytest.raises(RpcError):
+        l1.rpc.delpay(payment_hash)
+
+    # payment unpayed with wrong status (pending status is a illegal imput)
+    with pytest.raises(RpcError):
+        l1.rpc.delpay(payment_hash, "pending")
+
+    with pytest.raises(RpcError):
+        l1.rpc.delpay(payment_hash, "invalid_status")
+
+
+def test_delpay(node_factory, bitcoind):
+    """
+    This unit test try to catch some error inside the command
+    delpay when it receives the correct input from the user
+    """
+
+    l1, l2 = node_factory.get_nodes(2)
+
+    amount_sat = 10 ** 6
+
+    # create l2->l1 channel.
+    l2.fundwallet(amount_sat * 5)
+    l1.rpc.connect(l2.info['id'], 'localhost', l2.port)
+    l2.rpc.fundchannel(l1.info['id'], amount_sat * 3)
+
+    # Let the channel confirm.
+    bitcoind.generate_block(6)
+    sync_blockheight(bitcoind, [l1, l2])
+
+    invl1 = l1.rpc.invoice(Millisatoshi(amount_sat * 2 * 1000), "j", "j")
+    l2.rpc.pay(invl1["bolt11"])
+
+    before_del_pay = l2.rpc.listpays()
+
+    l2.rpc.delpay(invl1["payment_hash"])
+
+    after_del_pay = l2.rpc.listpays()["pays"]
+    assert len(after_del_pay) == (len(before_del_pay) - 1)