trade_preimage

**trade_preimage (deprecated) **

The trade_preimage method returns the approximate fee amounts that are paid per the whole swap. Depending on the parameters, the function returns different results:

If the swap_method is buy or sell, then the result will include the taker_fee and the fee_to_send_taker_fee. The taker_fee amount is paid from the base coin balance if the swap_method is sell, else it is paid from the rel coin balance;
If the max field is true, then the result will include the volume.

This method can be used instead of max_taker_vol, if the max field is true and the swap_method is buy or sell. Use the resulting volume as an argument of the buy or sell requests.

Use the trade_preimage request with max = true and swap_method = "setprice" arguments to approximate the fee amounts only. Do not use the resulting volume as an argument of the setprice.

This function is deprecated. Please consider using trade_preimage v2.0 instead.

Arguments

Structure	Type	Description
base	string	the base currency of the request
rel	string	the rel currency of the request
swap_method	string	the name of the method whose preimage is requested. Possible values: `buy`, `sell`, `setprice`
price	numeric string or rational	the price in `rel` the user is willing to pay per one unit of the `base` coin
volume	numeric string or rational (optional)	the amount the user is willing to trade; ignored if `max = true` and `swap_method = setprice`, otherwise, it must be set
max	bool (optional)	whether to return the maximum available volume for `setprice` method; must not be set or `false` if `swap_method` is `buy` or `sell`

Response

Structure	Type	Description
result	object	an object containing the relevant information
result.base_coin_fee	object (`ExtendedFeeInfo`)	the approximate miner fee is paid per the whole swap concerning the `base` coin
result.rel_coin_fee	object (`ExtendedFeeInfo`)	the approximate miner fee is paid per the whole swap concerning the `rel` coin
result.volume	string (numeric, optional)	the max available volume that can be traded (in decimal representation); empty if the `max` argument is missing or false
result.volume_rat	rational (optional)	the max available volume that can be traded (in rational representation); empty if the `max` argument is missing or false
result.volume_fraction	fraction (optional)	the max available volume that can be traded (in fraction representation); empty if the `max` argument is missing or false
result.taker_fee	object (optional, `ExtendedFeeInfo`)	the dex fee to be paid by Taker; empty if `swap_method` is `setprice`
result.fee_to_send_taker_fee	object (optional, `ExtendedFeeInfo`)	the approximate miner fee is paid to send the dex fee; empty if `swap_method` is `setprice`
result.total_fees	array of `TotalFeeInfo` objects	each element is a sum of fees required to be paid from user's balance of corresponding `ExtendedFeeInfo.coin`; the elements are unique by coin

The ExtendedFeeInfo structure is as follows:

Structure	Type	Description
coin	string	the fee is paid from the user's balance of this coin. This coin name may differ from the `base` or `rel` coins. For example, ERC20 fees are paid by ETH (gas)
amount	string (numeric)	fee amount (in decimal representation)
amount_rat	rational	fee amount (in rational representation)
amount_fraction	fraction	fee amount (in fraction representation)
amount_fraction	fraction	fee amount (in fraction representation)
paid_from_trading_vol	bool	whether the fee is paid from trading volume and not use actual `coin` balance

The TotalFeeInfo structure is as follows:

Structure	Type	Description
coin	string	the fee is paid from the user's balance of this coin. This coin name may differ from the `base` or `rel` coins. For example, ERC20 fees are paid by ETH (gas)
amount	string (numeric)	fee amount (in decimal representation)
amount_rat	rational	fee amount (in rational representation)
amount_fraction	fraction	fee amount (in fraction representation)
required_balance	string (numeric)	the required `coin` balance to pay the fee
required_balance_rat	rational	`required_balance` in rational representation
required_balance_fraction	fraction	`required_balance` in fraction representation

📌 Examples

Command (setprice)

POST

trade_preimage

{
  "userpass": "testpsw",
  "method": "trade_preimage",
  "base": "DOC",
  "rel": "BTC",
  "price": "1",
  "volume": "0.1",
  "swap_method": "setprice"
}

Command (buy)

POST

trade_preimage

{
  "userpass": "testpsw",
  "method": "trade_preimage",
  "base": "BTC",
  "rel": "DOC",
  "price": "1",
  "volume": "0.1",
  "swap_method": "buy"
}

Command (ERC20 and QRC20)

POST

trade_preimage

{
  "userpass": "testpsw",
  "method": "trade_preimage",
  "base": "BAT",
  "rel": "QC",
  "price": "1",
  "volume": "2.21363478",
  "swap_method": "setprice"
}