Assigning economic activity to general ledger accounts using posting rules

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A posting module assigns journal entry lines generated by LUSID to represent economic activity in portfolios to general ledger accounts. See how to create a posting module.

A posting module contains posting rules in a specific order. A posting rule assigns debit or credit amounts for journal entry lines matching a set of criteria to a specific account. Syntax of a posting rule.

For each journal entry line, LUSID applies the first matching posting rule found in the posting module. Unmatched journal entry lines remain unassigned. The goal of a posting module is to create a waterfall of logic that ensures all economic activity is assigned.

Consider the following example, of a posting module with five rules:

{
  "values": [
    {
      "ruleId": "rule_01",
      "account": "3-Capital",
      "ruleFilter": "EconomicBucket startswith 'CA'"
    },
    {
      "ruleId": "rule_02",
      "account": "1-Investments",
      "ruleFilter": "HoldType eq 'P' and EconomicBucket startswith 'NA'"
    },
    {
      "ruleId": "rule_03",
      "account": "4-PnL",
      "ruleFilter": "EconomicBucket startswith 'PL'"
    },
    {
      "ruleId": "rule_04",
      "account": "2-Cash",
      "ruleFilter": "HoldType neq 'P' and EconomicBucket startswith 'NA'"
    },
    {
      "ruleId": "rule_05",
      "account": "Error",
      "ruleFilter": "True"
    }
  ]
}

For each generated journal entry line, LUSID automatically:

Assigns the amount to the 3-Capital account if the economic bucket starts with CA.
If not, assigns the amount to the 1-Investments account if the economic bucket starts with NA and the holding type code is P (position, signifying a non-currency holding).
If not, assigns the amount to the 4-PnL account if the economic bucket starts with PL.
If not, assigns the amount to the 2-Cash account if the economic bucket starts with NA and the holding type code is not equal to P (that is, currency holdings).
If not, assigns the amount to an Error account for manual remediation.

In this example, rule 5 is a 'catch all' rule that assigns unmatched journal entry lines to a general-purpose account. You could omit rule 5, in which case any journal entry lines failing to match rules 1, 2, 3 and 4 remain unassigned.

Syntax of a posting rule

A posting rule consists of:

A ruleId that uniquely identifies the posting rule in the posting module.
An account that is the code of an account in the parent chart of accounts (CoA).
A ruleFilter expression that describes criteria for matching journal entry lines to the account.

The syntax of a ruleFilter expression is:

<attribute> <operator> <value>

...where:

<attribute> and <value> are explained in the table below.
<operator> is one of the LUSID filter operators.

`<attribute>`	Data type	Example expression	Explanation/origin of `<value>`
`SourceType`	String	`SourceType eq 'LusidTransaction'`	Either `LusidTransaction` or `LusidValuation`. Use `LusidValuation` to map LUSID's automatic mark-to-market valuation activity to an account.
`ActivityDate`	DateTime	`ActivityDate gt 2023-01-01`	For a transaction, this is the trade date. For a valuation, this is the date of the latest detected change to market data.
`EconomicBucket`	String	`EconomicBucket startswith 'PL_Real'`	LUSID automatically categorises every journal entry line into a broad economic bucket. More information.
`SourceId`	String	`SourceId eq 'Txn01'`	For a transaction, this is the unique identifier in the portfolio (`txnId`). For a valuation, this is the date and time of the latest change to market data (stored as a string, so only string operators are available).
`TaxLotId`	String	`SourceId eq 'Txn01'`	For a transaction, if the underlying instrument is a currency and the trade is settled (holding type of `B`), the value is `1` (stored as a string). Otherwise, this is the same as the `SourceId`.
`LocalAmount`	Decimal	`LocalAmount lte 1000`	The amount in the transaction currency.
`BaseAmount`	Decimal	`BaseAmount gt 450000`	The amount in the portfolio base currency.
`DefaultCurrency`	String	`DefaultCurrency in 'GBP', 'USD'`	The currency of the underlying instrument, if specified.
`InstrumentScope`	String	`InstrumentScope startswith 'Custom'`	The instrument scope in which the underlying instrument is mastered.
`LusidInstrumentId`	String	`LusidInstrumentId not startswith 'CCY'`	The LUID (globally unique ID) of the underlying instrument.
`HoldType`	String	`HoldType eq 'P'`	One of the LUSID holding type codes.
`MovementName`	String	`MovementName eq 'Side1'`	For a transaction, this is the name of the movement in the transaction type to which the transaction belongs. If the movement does not have a name (and note its `name` field is optional), then this is the name of the movement's side. For a valuation, this is always `MarkToMarket`.
`MovementSign`	String	`MovementSign eq 'Long'`	Either `Long` or `Short`.
A sub-holding key on the portfolio	User-defined	`subholdingkeys[Transaction/Ibor/Strategy] eq 'Income'`	Under-the-hood, a SHK is defined as a custom property with a 3-stage key in the `Transaction` domain.
A portfolio field	System-defined	`Portfolio.displayName eq 'UK-Equities' Portfolio.parentPortfolioId.Code eq 'FixedIncome'`	This can be any of the stored fields for a portfolio except the `href`, `links` and `version` fields, prefixed by `Portfolio.` Nested fields can be accessed using dot notation.
A portfolio property	User-defined	`properties[Portfolio/Ibor/Manager] in 'John Smith', 'Jane Jones'`	This can be any property with a 3-stage key in the Portfolio domain.
An instrument field	System-defined	`Instrument.identifiers['LusidInstrumentId'] eq 'LUID_ZZZZZZZZ' Instrument.instrumentDefinition.instrumentType in 'Equity', 'Bond'`	This can be any of the stored fields for an instrument except the `href`, `links` and `version` fields, prefixed by `Instrument.` Nested fields can be accessed using dot notation.
An instrument property	User-defined	`properties[Instrument/Ibor/AnalystRating] any (~ startswith 'A')`	This can be any property with a 3-stage key in the `Instrument` domain.
A transaction field	System-defined	`Transaction.totalConsideration.amount gt 2000 Transaction.instrumentScope eq 'ProtectedScope'`	This can be any of the stored fields for a transaction, prefixed by `Transaction.` Nested fields can be accessed using dot notation.
A transaction property	User-defined	`properties[Transaction/Ibor/Broker] eq 'AcmeCorp'`	This can be any property with a 3-stage key in the `Transaction` domain.
An account field	System-defined	`Account.type in 'Asset', 'Liabilities'`	This can be any of the stored fields for an account, prefixed by `Account.` Nested fields can be accessed using dot notation.
An account property	User-defined	`properties[Account/Type/AssetClass] eq 'Equity'`	This can be any property with a 3-stage key in the `Account` domain.
An ABOR property	User-defined	`properties[Abor/Client/Accountant] not in 'Fred Bloggs', 'Sarah Smart'`	This can be any property with a 3-stage key in the `Abor` domain.

Note the following:

A ruleFilter expression is case-insensitive.
A string <value> must be enclosed in single straight quote marks (the %27 UTF-8 encoding).

You can concatenate expressions using the and and or operators, for example:

MovementName eq 'Side1' and subholdingkeys[Transaction/Ibor/Strategy] eq 'Income'

If you use both, standard boolean operator precedence applies:

InstrumentScope startswith 'Custom' or (LocalAmount lte 1000 and HoldType eq 'P')