json-dsv

json-dsv
=========


Transform JSON to delimiter-separated values, such as CSV and TSV. Supports streams.

Installation
------------

npm install json-dsv

Usage
-----

$3

``js
var JsonDSV = require('json-dsv');
var transformer = new JsonDSV(options);

readableStream
.pipe(transformer.dsv(addlOptions))
.pipe(writableStream);
`




$3


`js
var JsonDSV = require('json-dsv');
var transformer = new JsonDSV(options);

var data = data; // Object[]
transformer.dsv(data, options, function(err, dsv) {
// buffered dsv result
});
`




$3


`js
{
delimiter: ',', // use a different field separator char, eg \t
default: '' // if value is undefined at value path
includeHeader: true, // Boolean, determines whether or not CSV file will contain a title column
newLine: '\r\n', // String, overrides the default OS line ending (i.e. \n on Unix and \r\n on Windows).
fields: [
// Supports label -> simple path
{
label: 'some label', // (optional, column will be labeled 'path.to.something' if not defined)
value: 'path.to.something', // data.path.to.something
default: 'NULL' // default if value is not found (optional, overrides options.default for column)
},

// Supports label -> derived value
{
label: 'some label', // Supports duplicate labels (required, else your column will be labeled [function])
value: function(row) {
return row.path1 + row.path2;
},
default: 'NULL' // default if value fn returns undefined
},

// Supports Array path for nested values
{
value: ['path', 'to.something'] // {path: {'to.something': 'here'}}
},

// Support pathname -> pathvalue
'simplepath' // equivalent to {value:'simplepath'}
'path.to.value' // also equivalent to {label:'path.to.value', value:'path.to.value'}
]
}
`

$3

# new JsonDSV(options)

Constructs a new JSON-DSV transformer.

# JsonDSV.dsv([addlOptions])

Transforms data to DSV (CSV by default). Streams data per line.

.csv and .tsv are available as convenience methods.

Specified addlOptions override options.

`js
var options = {
fields: [{value: 'make', label: 'Brand'}, 'model']
};
var data = [
{ make: 'nissan', model: '350z'},
{ make: 'bmw', model: '328i'}
];

var JsonDSV = require('json-dsv');
var transformer = new JsonDSV(options);
var es = require('event-stream');

es.readArray(data)
.pipe(transformer.dsv())
.pipe(process.stdout);

// Brand,model
// nissan,350z
// bmw,328i
`


# JsonDSV.dsv(data[, addlOptions], callback])

Transforms data to DSV (CSV by default). Callback passes on buffered output.

.csv and .tsv are available as convenience methods.

Specified addlOptions override options.

`js
var options = {
fields: [{value: 'make', label: 'Brand'}, 'model']
};
var data = [
{ make: 'nissan', model: '350z'},
{ make: 'bmw', model: '328i'}
];

var JsonDSV = require('json-dsv');
var transformer = new JsonDSV(options);

transformer.dsv(data, function(err, csv) {
console.log(csv);
});

// Brand,model
// nissan,350z
// bmw,328i
``

$3

npm test