javascript mt940 bank statement parser
npm install mt940js-bank
mt940js is a SWIFT mt940 bank statement format parser for javascript (ES2015). Takes in text of mt940 file, puts out array of parsed statements and transactions.
See examples below.
``bash`
npm install mt940js
Main parser class - Parser - parses input text (e.g. read from a file) into array of statements (a file may contain one or more). Each output statement contains a set of attributes, describing opening balance, statement number, etc and also an array of transactions.
Example
`javascript
const mt940js = require('mt940js');
const parser = new mt940js.Parser();
const statements = parser.parse(fs.readFileSync('./some_path', 'utf8'));
for (let s of statements) {
console.log(s.number.statement, s.statementDate);
for (let t of s.transactions) {
console.log(t.amount, t.currency);
}
}
`
- transactionReference {string} - tag 20 referencerelatedReference
- {string} - tag 21 reference, optionalaccountIdentification
- {string} - tag 25 own bank account identificationnumber.statement
- {string} - tag 28 main statement numbernumber.sequence
- {string} - tag 28 statement sub number (sequence), optionalnumber.section
- {string} - tag 28 statement sub sub number (present on some banks), optionalopeningBalanceDate
- {Date} - tag 60 statement opening dateclosingBalanceDate
- {Date} - tag 62 statement closing dateclosingAvailableBalanceDate
- {Date} - tag 64 closing available balance date, default = closing dateforwardAvailableBalanceDate
- {Date} - tag 65 forward available balance date, default = closing available datestatementDate
- {Date} - abstraction for statement date = closingBalanceDate
- {string} - statement currency (USD, EUR ...)openingBalance
- {Number} - beginning balance of the statement (with sign, based on debit/credit mark)closingBalance
- {Number} - ending balance of the statement (with sign, based on debit/credit mark)closingAvailableBalance
- {Number} - tag 64 closing available balance, default = closing balanceforwardAvailableBalance
- {Number} - tag 65 forward available balance, default = closing availableinformationToAccountOwner
- {string} - additional statement level informationtransactions
- {array} - collection of transactionsmessageBlocks
- {object} - statement message blocks, if present (EXPERIMENTAL)
Each Transaction contains data of tag 61 (and tag 86 for details)
- date {Date} - transaction dateamount
- {Number} - transaction amount (with sign, Credit+, Debit-)reversal
- {Boolean} - transaction is a reversalcurrency
- {string} - transaction currency (copy of statement currency)details
- {string} - content of relevant 86 tag(s), may be multiline (\n separated)transactionType
- {string} - MT940 transaction type code (e.g. NTRF ...)reference
- {string} - payment reference fieldentryDate
- {Date} - entry date field, optionalfundsCode
- {string} - funds code field, optionalbankReference
- {string} - bank reference, optionalextraDetails
- {string} - extra details (supplementary details), optionalstructuredDetails
- {Object} - structured details if detected, in for of { subtag: value } e.g. { '20': '123456' }
- {string} - optional, content of NS tag which happened in the context of transaction (after tags 61 or 86), can be multiline (separated by \n)
Each statement is validated for:
- all strictly required tags
- opening/closing balance currency is the same
- opening balance + turnover = closing balance
The Parser has just one method - parse(data, withTags = false) - which will convert raw mt940 string to an array of statements described above. The optional withTags parameter would preserve parsed tags to an additional tags attribute of a statement (for any additional further analysis).
Currently the library supports the following tag formats:
- ', where can be '>' or '?'
- , where TAG is 2 to 4 uppercase chars.
Example:
`
'>20some details >30more data'
or
'/ORDP/Smith Corp'
The parser attempts to detect if field 86 contains tags like these and, if yes, adds structuredDetails attribute to a statement line. Tag digits are not interpreted as they are not standardized among different banks. Parsing 86 structure can be force disabled by passing { no86Structure: true } to the constructor.
`javascript
// let incoming file contain one line with 86 field:
// '>20some details>30more data'
const statements = ... // parsing here
for (let s of statements) {
for (let t of s.transactions) {
console.log(t.structuredDetails);
// { '20': 'some details',
// '30': 'more data' }
}
}
`
Currently experimental, may change
The library support post processing middlewares which is called before returning parsed result. To append a middleware call usePostParse passing fn(statement, next). Middlewares are called in the order of appending. Middlewares modify statement object directly. Beware that input data may contain several statements, middlewares are called over each of them one by one.
`javascript``
const parser = new Parser();
parser.usePostParse((s, next) => {
s.hasOverdraft = (s.closingBalance < 0);
next();
});