Taking a sell order

If the order amount is 0 the buyer don't know the exact amount to create the invoice, buyer will send a message in a Nostr event kind 4 to Mostro with the following content:

{
  "order": {
    "version": 1,
    "id": "ede61c96-4c13-4519-bf3a-dcf7f1e9d842",
    "pubkey": "0000147e939bef2b81c27af4c1b702c90c3843f7212a34934bff1e049b7f1427",
    "action": "take-sell",
    "content": null
  }
}

The event to send to Mostro would look like this:

{
  "id": "cade205b849a872d74ba4d2a978135dbc05b4e5f483bb4403c42627dfd24f67d",
  "kind": 4,
  "pubkey": "9a42ac72d6466a6dbe5b4b07a8717ee13e55abb6bdd810ea9c321c9a32ee837b",
  "content": "base64-encoded-aes-256-cbc-encrypted-JSON-serialized-string",
  "tags": [
    ["p", "dbe0b1be7aafd3cfba92d7463edbd4e33b2969f61bd554d37ac56f032e13355a"]
  ],
  "created_at": 1234567890,
  "sig": "a21eb195fe418613aa9a3a8a78039b090e50dc3f9fb06b0f3fe41c63221adc073a9317a1f28d9db843a43c28d860ba173b70132ca85b0e706f6487d43a57ee82"
}

Mostro response

In order to continue the buyer needs to send a lightning network invoice to Mostro, in this case the amount of the order is 0, so Mostro will need to calculate the amount of sats for this order, then Mostro will send back a message asking for a LN invoice indicating the correct amount of sats that the invoice should have, here the unencrypted content of the message:

{
  "order": {
    "version": 1,
    "id": "ede61c96-4c13-4519-bf3a-dcf7f1e9d842",
    "pubkey": null,
    "action": "add-invoice",
    "content": {
      "order": {
        "id": "ede61c96-4c13-4519-bf3a-dcf7f1e9d842",
        "amount": 7851,
        "fiat_code": "VES",
        "fiat_amount": 100,
        "payment_method": "face to face",
        "premium": 1,
        "buyer_pubkey": null,
        "seller_pubkey": null
      }
    }
  }
}

Mostro updates the nip 33 event with d tag ede61c96-4c13-4519-bf3a-dcf7f1e9d842 to change the status to waiting-buyer-invoice:

[
  "EVENT",
  "RAND",
  {
    "id": "eb0582360ebd3836c90711f774fbecb27e600f4a5fedf4fc2d16fc852f8380b1",
    "pubkey": "dbe0b1be7aafd3cfba92d7463edbd4e33b2969f61bd554d37ac56f032e13355a",
    "created_at": 1702549437,
    "kind": 38383,
    "tags": [
      ["d", "ede61c96-4c13-4519-bf3a-dcf7f1e9d842"],
      ["k", "sell"],
      ["f", "VES"],
      ["s", "waiting-buyer-invoice"],
      ["amt", "7851"],
      ["fa", "100"],
      ["pm", "face to face"],
      ["premium", "1"],
      ["y", "mostrop2p"],
      ["z", "order"]
    ],
    "content": "",
    "sig": "a835f8620db3ebdd9fa142ae99c599a61da86321c60f7c9fed0cc57169950f4121757ff64a5e998baccf6b68272aa51819c3e688d8ad586c0177b3cd1ab09c0f"
  }
]

Buyer sends LN invoice

The buyer sends a nip 04 event to Mostro with the lightning invoice, the action should be the same the buyer just received in the last message from Mostro (add-invoice), here the unencrypted content of the event:

{
  "order": {
    "version": 1,
    "id": "ede61c96-4c13-4519-bf3a-dcf7f1e9d842",
    "pubkey": null,
    "action": "add-invoice",
    "content": {
      "payment_request": [
        null,
        "lnbcrt78510n1pj59wmepp50677g8tffdqa2p8882y0x6newny5vtz0hjuyngdwv226nanv4uzsdqqcqzzsxqyz5vqsp5skn973360gp4yhlpmefwvul5hs58lkkl3u3ujvt57elmp4zugp4q9qyyssqw4nzlr72w28k4waycf27qvgzc9sp79sqlw83j56txltz4va44j7jda23ydcujj9y5k6k0rn5ms84w8wmcmcyk5g3mhpqepf7envhdccp72nz6e"
      ]
    }
  }
}

Mostro response

Mostro send a nip 04 event to the buyer with a wrapped order in the content, it would look like this:

{
  "order": {
    "version": 1,
    "id": "ede61c96-4c13-4519-bf3a-dcf7f1e9d842",
    "pubkey": null,
    "action": "waiting-seller-to-pay",
    "content": null
  }
}

Mostro updates the nip 33 event with d tag ede61c96-4c13-4519-bf3a-dcf7f1e9d842 to change the status to WaitingPayment:

[
  "EVENT",
  "RAND",
  {
    "id": "eb0582360ebd3836c90711f774fbecb27e600f4a5fedf4fc2d16fc852f8380b1",
    "pubkey": "dbe0b1be7aafd3cfba92d7463edbd4e33b2969f61bd554d37ac56f032e13355a",
    "created_at": 1702549437,
    "kind": 38383,
    "tags": [
      ["d", "ede61c96-4c13-4519-bf3a-dcf7f1e9d842"],
      ["k", "sell"],
      ["f", "VES"],
      ["s", "waiting-payment"],
      ["amt", "7851"],
      ["fa", "100"],
      ["pm", "face to face"],
      ["premium", "1"],
      ["y", "mostrop2p"],
      ["z", "order"]
    ],
    "content": "",
    "sig": "a835f8620db3ebdd9fa142ae99c599a61da86321c60f7c9fed0cc57169950f4121757ff64a5e998baccf6b68272aa51819c3e688d8ad586c0177b3cd1ab09c0f"
  }
]