The Nexus API, and according commands support varying types of operators. Operators allow computation to be performed on a filtered data-set, much like in an excel spreadsheet.
The minimum required components of the URI for an operator is:
commands/verb/noun/filter/operator
FilterIn order to execute an operator, one must apply a basic filter to the data-set because we need to isolate a component of the returned data to operate on and return.
Take the following contract list:
{
"id": 33,
"OP": "CREDIT",
"for": "COINBASE",
"txid": "01625b58e131e61813f77e8e97404cb587d780c7951b055b4f531f2a8ea5a63fc3c95f179ec26fa138e639143615a10961719ffb1b33dd98e64d0bf4d9fe50ae",
"contract": 2,
"to": "8BAv1H2YKfpaYC1RJMq9qjmMTiEV8DJiLpiKGqTY54wf2VPjznD",
"amount": 208.833665,
"token": "0",
"ticker": "NXS"
},
{
"id": 34,
"OP": "CREDIT",
"for": "COINBASE",
"txid": "01b7291259fda66e8dbde6de502bd811894e42b6f2dd9fc684bdf87e9a3f0f224e16df72c491355547191af28f1cdd84bed0b522686de837f5b346593646f40f",
"contract": 2,
"to": "8BAv1H2YKfpaYC1RJMq9qjmMTiEV8DJiLpiKGqTY54wf2VPjznD",
"amount": 205.705007,
"token": "0",
"ticker": "NXS"
},
To operate on our amount field, we would first need to apply a filter:
commands/verb/noun/amount
This command will now prepare for an operator, that can be invoked by finishing the URI:
commands/verb/noun/amount/sum
This above command will return a JSON object with our filtered result:
{
"amount": 414.53867,
}
OperatorsThe following operators are supported for this API command-set:
array - Generate a list of values given from a set of filtered results as a JSON array.
count - Find the total number of entries returned in a given JSON list.
floor - Convert all values in a result to integers by stripping off decimals.
max - Find the maximum value in the given set, and return this as result.
mean - Calculate the mean or average value across a set of filtered results.
min - Find the minimum value in the given set, and return this as result.
mode - Find the value with the most occurrences across the data-set.
sum - Compute a sum of a set of values derived from filtered results.
Example:
finance/list/accounts/balance/sum
Result:
This command will return a sum of the balances for all accounts:
{
"balance": 333.376
}