TransactionParser

Parse files containing transaction data using COBOL copybooks into a TypeScript object.

Documentation is published on Github Pages.

Table of Contents

• Parse copybooks
  • Example
• Transaction Packages and Transactions
  • Usage
  • Editing data from a transaction
  • Saving data
• Events
  • Copybook parsing
    • start event
    • newLine event
    • endLine event
    • end event
• CLI
  • Installation
  • Usage
    • Convert data to JSON
    • Convert data to CSV

Parse copybooks

This package supports parsing a copybook into a TypeScript object.

const parser = new CopybookParser('/path/to/copybook'); // Supports any extension
parser.parse(); // Load copybook as object

parser.getParsedCopybook(); // Retrieve copybook as object
parser.toJson(); // Retrieve copybook as JSON string
Copy

Want to use a different copybook? Just update the path to the copybook:

parser.updateCopybookPath('/path/to/another/copybook');
Copy

Note: This will clear previously parsed copybook data

Example

The following copybook:

       01 CUSTOMER-RECORD.
          05 CUSTOMER-NAME.
             10 FIRST-NAME             PIC X(15).
Copy

Will be parsed and represented as a JSON object:

[
  {
    "level": 1,
    "name": "CUSTOMER-RECORD",
    "picture": "group",
    "length": 0,
    "signed": false,
    "usage": "display",
    "dataPosition": {
      "offset": 0,
      "byteLength": 0
    },
    "decimals": 0,
    "children": [
      {
        "level": 5,
        "name": "CUSTOMER-NAME",
        "picture": "group",
        "length": 0,
        "signed": false,
        "usage": "display",
        "dataPosition": {
          "offset": 0,
          "byteLength": 0
        },
        "decimals": 0,
        "children": [
          {
            "level": 10,
            "name": "FIRST-NAME",
            "picture": "string",
            "length": 15,
            "signed": false,
            "usage": "display",
            "dataPosition": {
              "offset": 0,
              "byteLength": 15
            },
            "decimals": 0,
            "value": "               "
          }
        ]
      }
    ]
  }
]
Copy

Transaction Packages and Transactions

This package uses the term transaction package to indicate a package containing zero or more transactions. A Transaction is the representation of the parsed copybook and it's values.

Usage

Create a new (empty) transaction package:

import { TransactionPackage } from 'transactionparser';

const copybookPath = '/Path/to/copybook';
const tp = new TransactionPackage(copybookPath);
Copy

Once a transaction package is created, you can either fill it with empty transactions:

tp.createEmptyTransaction();
Copy

Or load the contents of a Mainframe file downloaded in binary mode:

const dataFile = '/Path/to/binary/file';
tp.loadFile(dataFile);
Copy

Editing data from a transaction

The transactions property on the transaction package can be used to retrieve an array of all transactions in the package. Alternatively, helper methods like getFirstTransaction() or getLastTransaction() are also available.

To update the value for the FIRST-NAME field, you can:

tp.transactions[0].getCopybookItem('FIRST-NAME').setValue('Jules');
Copy

Saving data

The TransactionPackage class provides the functionality to write the package back to a file, that can the, for example using the Zowe CLI, be uploaded back to the Mainframe.

tp.save('/path/my_modified_transaction');
Copy

Note: This uses the TransactionPackage#toBuffer() method which will add the new line character, EBCDIC byte x'15' at the end of every transaction.

Alternatively, you can also use the toJson() or toBuffer() methods to convert the transaction package to a stringyfied JSON array or buffer.

Events

This package emits typed events during certain stages of processing, for example when parsing a copybook.

Use the getEventEmitter() method on supported classes to subscribe to events. Events are supported in every class that implements the IEventSupport interface:

• CopybookParser

Example

const parser = new CopybookParser('/path/to/copybook')
const emitter = parser.getEventEmitter()

emitter.subscribe('start', (payload) => {
  console.log(payload) // Contains properties copybook, rawData and preparedData
})

const newLineFunc = (payload) => {
  console.log(payload)
}

emitter.subscribe('newLine', newLineFunc) // Subscribes to the 'newLine' event
emitter.unsubscribe('newLine', newLineFunc) // Unsubscribe from the 'newLine' event

emitter.once('endLine', (payload) => {
  console.log(payload) // Only logged once, for the first 'endLine' event
})
Copy

Copybook parsing

During parsing of a copybook, the following events are emitted:

• start
• newLine
• endLine
• end

start event

This event is emitted at the beginning of parsing a copybook

Property	Value
copybook	Path of the copybook that will be parsed
preparedData	Array of strings containing the lines to be parsed
rawData	Data loaded from the copybook file that will be processed after being prepared

preparedData is rawData splitted on every new line, tabs are replaced with (space). Only includes non-empty lines

newLine event

This event is emitted at the beginning of each new line that is parsed

Property	Value
copybook	Path of the copybook that is being parsed
line	Current line that is being parsed
parsedItems	Array of objects of previously parsed lines containing item (DataItem) and level (number) properties

endLine event

This event is emitted for each line when parsing has finished

Property	Value
copybook	Path of the copybook that is being parsed
line	Current line that is being parsed
newItem	Object representing the current line containing the item (DataItem) and level (number) properties
parsedItems	Array of objects of previously parsed lines containing item (DataItem) and level (number) properties

parsedItems will include newItem

end event

This event is emitted when parsing of the copybook is finished.

Property	Value
copybook	Path of the copybook that has been parsed
parsedCopybook	Array of DataItems into which the copybook has parsed. For these DataItem's, children, occurs and redefines clauses have been resolved.

Transaction Package

When using a transaction package, the following event are emitted:

• beforeParsing
• parsingComplete
• transactionLoaded
• transactionCreated
• transactionPackageSave

beforeParsing event

This event is emitted after CopybookParser instance is created and before actual parsing of the copybook.

Property	Value
parser	Instance of CopybookParser that is used to parse the provided copybook

Use parser.getEventEmitter() to subscribe to event that are emitted during copybook parsing. See Copybook Parsing

parsingCompleted event

This event is emitted after the parsing of a copybook provided when creating a transaction package has been completed

Property	Value
parser	Instance of CopybookParser that is used to parse the provided copybook.
parsedCopybook	An array of DataItem representing the parsed copybook

transactionLoaded event

This event is emitted when:

• A new transaction package instance is created
• When a transactions are loaded via the loadFile() or load() methods

Property	Value
parser	Instance of CopybookParser that is used to parse the provided copybook
transactions	Array of ITransaction instances that have been loaded into the transaction package

transactions is possibly an empty array

transactionCreated event

This event is emitted when a new transaction is created after the transaction package has been initialized by calling createEmptyTransaction()

Property	Value
parser	Instance of CopybookParser that is used to parse the provided copybook
newTransaction	ITransaction that was recently created
transactions	Array of ITransaction containing the transactions that are included in the current transaction package. This includes newTransaction

transactionPackageSave event

This event is emitted when a transaction package is stored to a file

Property	Value
parser	Instance of CopybookParser that is used to parse the provided copybook
transactions	Array of ITransaction containing all transactions that are included in the current transaction package
buffer	NodeJS Buffer containing the raw data that will be written to outputPath
outputPath	Path where the transaction package will be stored

CLI

This package also provides a Command Line Interface (CLI) to convert a (binairy) transaction file into a JSON or CSV file.

Installation

Install the package globally using:

npm i -g transactionparser
Copy

This will make the transactionparser (or the shorter traper version) available in your terminal.

Usage

• trapar -h Show Help info with available commands
• trapar parse -h Show help info for the parse command

Convert data to JSON

trapar parse 'path/to/data' -c 'path/to/copybook' -f 'JSON' -o 'output.txt' 
Copy

Convert the data at path/to/data using the copybook located at /path/to/copybook and format it to a JSON string stored in output.txt

Convert data to CSV

trapar parse 'path/to/data' -c 'path/to/copybook' -f 'CSV' -o 'output.csv' 
Copy