You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
710 lines
24 KiB
710 lines
24 KiB
4 weeks ago
|
<p align="center">
|
||
|
<img alt="qs" src="./logos/banner_default.png" width="800" />
|
||
|
</p>
|
||
|
|
||
|
# qs <sup>[![Version Badge][npm-version-svg]][package-url]</sup>
|
||
|
|
||
|
[![github actions][actions-image]][actions-url]
|
||
|
[![coverage][codecov-image]][codecov-url]
|
||
|
[![License][license-image]][license-url]
|
||
|
[![Downloads][downloads-image]][downloads-url]
|
||
|
[![CII Best Practices](https://bestpractices.coreinfrastructure.org/projects/9058/badge)](https://bestpractices.coreinfrastructure.org/projects/9058)
|
||
|
|
||
|
[![npm badge][npm-badge-png]][package-url]
|
||
|
|
||
|
A querystring parsing and stringifying library with some added security.
|
||
|
|
||
|
Lead Maintainer: [Jordan Harband](https://github.com/ljharb)
|
||
|
|
||
|
The **qs** module was originally created and maintained by [TJ Holowaychuk](https://github.com/visionmedia/node-querystring).
|
||
|
|
||
|
## Usage
|
||
|
|
||
|
```javascript
|
||
|
var qs = require('qs');
|
||
|
var assert = require('assert');
|
||
|
|
||
|
var obj = qs.parse('a=c');
|
||
|
assert.deepEqual(obj, { a: 'c' });
|
||
|
|
||
|
var str = qs.stringify(obj);
|
||
|
assert.equal(str, 'a=c');
|
||
|
```
|
||
|
|
||
|
### Parsing Objects
|
||
|
|
||
|
[](#preventEval)
|
||
|
```javascript
|
||
|
qs.parse(string, [options]);
|
||
|
```
|
||
|
|
||
|
**qs** allows you to create nested objects within your query strings, by surrounding the name of sub-keys with square brackets `[]`.
|
||
|
For example, the string `'foo[bar]=baz'` converts to:
|
||
|
|
||
|
```javascript
|
||
|
assert.deepEqual(qs.parse('foo[bar]=baz'), {
|
||
|
foo: {
|
||
|
bar: 'baz'
|
||
|
}
|
||
|
});
|
||
|
```
|
||
|
|
||
|
When using the `plainObjects` option the parsed value is returned as a null object, created via `Object.create(null)` and as such you should be aware that prototype methods will not exist on it and a user may set those names to whatever value they like:
|
||
|
|
||
|
```javascript
|
||
|
var nullObject = qs.parse('a[hasOwnProperty]=b', { plainObjects: true });
|
||
|
assert.deepEqual(nullObject, { a: { hasOwnProperty: 'b' } });
|
||
|
```
|
||
|
|
||
|
By default parameters that would overwrite properties on the object prototype are ignored, if you wish to keep the data from those fields either use `plainObjects` as mentioned above, or set `allowPrototypes` to `true` which will allow user input to overwrite those properties.
|
||
|
*WARNING* It is generally a bad idea to enable this option as it can cause problems when attempting to use the properties that have been overwritten.
|
||
|
Always be careful with this option.
|
||
|
|
||
|
```javascript
|
||
|
var protoObject = qs.parse('a[hasOwnProperty]=b', { allowPrototypes: true });
|
||
|
assert.deepEqual(protoObject, { a: { hasOwnProperty: 'b' } });
|
||
|
```
|
||
|
|
||
|
URI encoded strings work too:
|
||
|
|
||
|
```javascript
|
||
|
assert.deepEqual(qs.parse('a%5Bb%5D=c'), {
|
||
|
a: { b: 'c' }
|
||
|
});
|
||
|
```
|
||
|
|
||
|
You can also nest your objects, like `'foo[bar][baz]=foobarbaz'`:
|
||
|
|
||
|
```javascript
|
||
|
assert.deepEqual(qs.parse('foo[bar][baz]=foobarbaz'), {
|
||
|
foo: {
|
||
|
bar: {
|
||
|
baz: 'foobarbaz'
|
||
|
}
|
||
|
}
|
||
|
});
|
||
|
```
|
||
|
|
||
|
By default, when nesting objects **qs** will only parse up to 5 children deep.
|
||
|
This means if you attempt to parse a string like `'a[b][c][d][e][f][g][h][i]=j'` your resulting object will be:
|
||
|
|
||
|
```javascript
|
||
|
var expected = {
|
||
|
a: {
|
||
|
b: {
|
||
|
c: {
|
||
|
d: {
|
||
|
e: {
|
||
|
f: {
|
||
|
'[g][h][i]': 'j'
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
};
|
||
|
var string = 'a[b][c][d][e][f][g][h][i]=j';
|
||
|
assert.deepEqual(qs.parse(string), expected);
|
||
|
```
|
||
|
|
||
|
This depth can be overridden by passing a `depth` option to `qs.parse(string, [options])`:
|
||
|
|
||
|
```javascript
|
||
|
var deep = qs.parse('a[b][c][d][e][f][g][h][i]=j', { depth: 1 });
|
||
|
assert.deepEqual(deep, { a: { b: { '[c][d][e][f][g][h][i]': 'j' } } });
|
||
|
```
|
||
|
|
||
|
You can configure **qs** to throw an error when parsing nested input beyond this depth using the `strictDepth` option (defaulted to false):
|
||
|
|
||
|
```javascript
|
||
|
try {
|
||
|
qs.parse('a[b][c][d][e][f][g][h][i]=j', { depth: 1, strictDepth: true });
|
||
|
} catch (err) {
|
||
|
assert(err instanceof RangeError);
|
||
|
assert.strictEqual(err.message, 'Input depth exceeded depth option of 1 and strictDepth is true');
|
||
|
}
|
||
|
```
|
||
|
|
||
|
The depth limit helps mitigate abuse when **qs** is used to parse user input, and it is recommended to keep it a reasonably small number. The strictDepth option adds a layer of protection by throwing an error when the limit is exceeded, allowing you to catch and handle such cases.
|
||
|
|
||
|
For similar reasons, by default **qs** will only parse up to 1000 parameters. This can be overridden by passing a `parameterLimit` option:
|
||
|
|
||
|
```javascript
|
||
|
var limited = qs.parse('a=b&c=d', { parameterLimit: 1 });
|
||
|
assert.deepEqual(limited, { a: 'b' });
|
||
|
```
|
||
|
|
||
|
To bypass the leading question mark, use `ignoreQueryPrefix`:
|
||
|
|
||
|
```javascript
|
||
|
var prefixed = qs.parse('?a=b&c=d', { ignoreQueryPrefix: true });
|
||
|
assert.deepEqual(prefixed, { a: 'b', c: 'd' });
|
||
|
```
|
||
|
|
||
|
An optional delimiter can also be passed:
|
||
|
|
||
|
```javascript
|
||
|
var delimited = qs.parse('a=b;c=d', { delimiter: ';' });
|
||
|
assert.deepEqual(delimited, { a: 'b', c: 'd' });
|
||
|
```
|
||
|
|
||
|
Delimiters can be a regular expression too:
|
||
|
|
||
|
```javascript
|
||
|
var regexed = qs.parse('a=b;c=d,e=f', { delimiter: /[;,]/ });
|
||
|
assert.deepEqual(regexed, { a: 'b', c: 'd', e: 'f' });
|
||
|
```
|
||
|
|
||
|
Option `allowDots` can be used to enable dot notation:
|
||
|
|
||
|
```javascript
|
||
|
var withDots = qs.parse('a.b=c', { allowDots: true });
|
||
|
assert.deepEqual(withDots, { a: { b: 'c' } });
|
||
|
```
|
||
|
|
||
|
Option `decodeDotInKeys` can be used to decode dots in keys
|
||
|
Note: it implies `allowDots`, so `parse` will error if you set `decodeDotInKeys` to `true`, and `allowDots` to `false`.
|
||
|
|
||
|
```javascript
|
||
|
var withDots = qs.parse('name%252Eobj.first=John&name%252Eobj.last=Doe', { decodeDotInKeys: true });
|
||
|
assert.deepEqual(withDots, { 'name.obj': { first: 'John', last: 'Doe' }});
|
||
|
```
|
||
|
|
||
|
Option `allowEmptyArrays` can be used to allowing empty array values in object
|
||
|
```javascript
|
||
|
var withEmptyArrays = qs.parse('foo[]&bar=baz', { allowEmptyArrays: true });
|
||
|
assert.deepEqual(withEmptyArrays, { foo: [], bar: 'baz' });
|
||
|
```
|
||
|
|
||
|
Option `duplicates` can be used to change the behavior when duplicate keys are encountered
|
||
|
```javascript
|
||
|
assert.deepEqual(qs.parse('foo=bar&foo=baz'), { foo: ['bar', 'baz'] });
|
||
|
assert.deepEqual(qs.parse('foo=bar&foo=baz', { duplicates: 'combine' }), { foo: ['bar', 'baz'] });
|
||
|
assert.deepEqual(qs.parse('foo=bar&foo=baz', { duplicates: 'first' }), { foo: 'bar' });
|
||
|
assert.deepEqual(qs.parse('foo=bar&foo=baz', { duplicates: 'last' }), { foo: 'baz' });
|
||
|
```
|
||
|
|
||
|
If you have to deal with legacy browsers or services, there's also support for decoding percent-encoded octets as iso-8859-1:
|
||
|
|
||
|
```javascript
|
||
|
var oldCharset = qs.parse('a=%A7', { charset: 'iso-8859-1' });
|
||
|
assert.deepEqual(oldCharset, { a: '§' });
|
||
|
```
|
||
|
|
||
|
Some services add an initial `utf8=✓` value to forms so that old Internet Explorer versions are more likely to submit the form as utf-8.
|
||
|
Additionally, the server can check the value against wrong encodings of the checkmark character and detect that a query string or `application/x-www-form-urlencoded` body was *not* sent as utf-8, eg. if the form had an `accept-charset` parameter or the containing page had a different character set.
|
||
|
|
||
|
**qs** supports this mechanism via the `charsetSentinel` option.
|
||
|
If specified, the `utf8` parameter will be omitted from the returned object.
|
||
|
It will be used to switch to `iso-8859-1`/`utf-8` mode depending on how the checkmark is encoded.
|
||
|
|
||
|
**Important**: When you specify both the `charset` option and the `charsetSentinel` option, the `charset` will be overridden when the request contains a `utf8` parameter from which the actual charset can be deduced.
|
||
|
In that sense the `charset` will behave as the default charset rather than the authoritative charset.
|
||
|
|
||
|
```javascript
|
||
|
var detectedAsUtf8 = qs.parse('utf8=%E2%9C%93&a=%C3%B8', {
|
||
|
charset: 'iso-8859-1',
|
||
|
charsetSentinel: true
|
||
|
});
|
||
|
assert.deepEqual(detectedAsUtf8, { a: 'ø' });
|
||
|
|
||
|
// Browsers encode the checkmark as ✓ when submitting as iso-8859-1:
|
||
|
var detectedAsIso8859_1 = qs.parse('utf8=%26%2310003%3B&a=%F8', {
|
||
|
charset: 'utf-8',
|
||
|
charsetSentinel: true
|
||
|
});
|
||
|
assert.deepEqual(detectedAsIso8859_1, { a: 'ø' });
|
||
|
```
|
||
|
|
||
|
If you want to decode the `&#...;` syntax to the actual character, you can specify the `interpretNumericEntities` option as well:
|
||
|
|
||
|
```javascript
|
||
|
var detectedAsIso8859_1 = qs.parse('a=%26%239786%3B', {
|
||
|
charset: 'iso-8859-1',
|
||
|
interpretNumericEntities: true
|
||
|
});
|
||
|
assert.deepEqual(detectedAsIso8859_1, { a: '☺' });
|
||
|
```
|
||
|
|
||
|
It also works when the charset has been detected in `charsetSentinel` mode.
|
||
|
|
||
|
### Parsing Arrays
|
||
|
|
||
|
**qs** can also parse arrays using a similar `[]` notation:
|
||
|
|
||
|
```javascript
|
||
|
var withArray = qs.parse('a[]=b&a[]=c');
|
||
|
assert.deepEqual(withArray, { a: ['b', 'c'] });
|
||
|
```
|
||
|
|
||
|
You may specify an index as well:
|
||
|
|
||
|
```javascript
|
||
|
var withIndexes = qs.parse('a[1]=c&a[0]=b');
|
||
|
assert.deepEqual(withIndexes, { a: ['b', 'c'] });
|
||
|
```
|
||
|
|
||
|
Note that the only difference between an index in an array and a key in an object is that the value between the brackets must be a number to create an array.
|
||
|
When creating arrays with specific indices, **qs** will compact a sparse array to only the existing values preserving their order:
|
||
|
|
||
|
```javascript
|
||
|
var noSparse = qs.parse('a[1]=b&a[15]=c');
|
||
|
assert.deepEqual(noSparse, { a: ['b', 'c'] });
|
||
|
```
|
||
|
|
||
|
You may also use `allowSparse` option to parse sparse arrays:
|
||
|
|
||
|
```javascript
|
||
|
var sparseArray = qs.parse('a[1]=2&a[3]=5', { allowSparse: true });
|
||
|
assert.deepEqual(sparseArray, { a: [, '2', , '5'] });
|
||
|
```
|
||
|
|
||
|
Note that an empty string is also a value, and will be preserved:
|
||
|
|
||
|
```javascript
|
||
|
var withEmptyString = qs.parse('a[]=&a[]=b');
|
||
|
assert.deepEqual(withEmptyString, { a: ['', 'b'] });
|
||
|
|
||
|
var withIndexedEmptyString = qs.parse('a[0]=b&a[1]=&a[2]=c');
|
||
|
assert.deepEqual(withIndexedEmptyString, { a: ['b', '', 'c'] });
|
||
|
```
|
||
|
|
||
|
**qs** will also limit specifying indices in an array to a maximum index of `20`.
|
||
|
Any array members with an index of greater than `20` will instead be converted to an object with the index as the key.
|
||
|
This is needed to handle cases when someone sent, for example, `a[999999999]` and it will take significant time to iterate over this huge array.
|
||
|
|
||
|
```javascript
|
||
|
var withMaxIndex = qs.parse('a[100]=b');
|
||
|
assert.deepEqual(withMaxIndex, { a: { '100': 'b' } });
|
||
|
```
|
||
|
|
||
|
This limit can be overridden by passing an `arrayLimit` option:
|
||
|
|
||
|
```javascript
|
||
|
var withArrayLimit = qs.parse('a[1]=b', { arrayLimit: 0 });
|
||
|
assert.deepEqual(withArrayLimit, { a: { '1': 'b' } });
|
||
|
```
|
||
|
|
||
|
To disable array parsing entirely, set `parseArrays` to `false`.
|
||
|
|
||
|
```javascript
|
||
|
var noParsingArrays = qs.parse('a[]=b', { parseArrays: false });
|
||
|
assert.deepEqual(noParsingArrays, { a: { '0': 'b' } });
|
||
|
```
|
||
|
|
||
|
If you mix notations, **qs** will merge the two items into an object:
|
||
|
|
||
|
```javascript
|
||
|
var mixedNotation = qs.parse('a[0]=b&a[b]=c');
|
||
|
assert.deepEqual(mixedNotation, { a: { '0': 'b', b: 'c' } });
|
||
|
```
|
||
|
|
||
|
You can also create arrays of objects:
|
||
|
|
||
|
```javascript
|
||
|
var arraysOfObjects = qs.parse('a[][b]=c');
|
||
|
assert.deepEqual(arraysOfObjects, { a: [{ b: 'c' }] });
|
||
|
```
|
||
|
|
||
|
Some people use comma to join array, **qs** can parse it:
|
||
|
```javascript
|
||
|
var arraysOfObjects = qs.parse('a=b,c', { comma: true })
|
||
|
assert.deepEqual(arraysOfObjects, { a: ['b', 'c'] })
|
||
|
```
|
||
|
(_this cannot convert nested objects, such as `a={b:1},{c:d}`_)
|
||
|
|
||
|
### Parsing primitive/scalar values (numbers, booleans, null, etc)
|
||
|
|
||
|
By default, all values are parsed as strings.
|
||
|
This behavior will not change and is explained in [issue #91](https://github.com/ljharb/qs/issues/91).
|
||
|
|
||
|
```javascript
|
||
|
var primitiveValues = qs.parse('a=15&b=true&c=null');
|
||
|
assert.deepEqual(primitiveValues, { a: '15', b: 'true', c: 'null' });
|
||
|
```
|
||
|
|
||
|
If you wish to auto-convert values which look like numbers, booleans, and other values into their primitive counterparts, you can use the [query-types Express JS middleware](https://github.com/xpepermint/query-types) which will auto-convert all request query parameters.
|
||
|
|
||
|
### Stringifying
|
||
|
|
||
|
[](#preventEval)
|
||
|
```javascript
|
||
|
qs.stringify(object, [options]);
|
||
|
```
|
||
|
|
||
|
When stringifying, **qs** by default URI encodes output. Objects are stringified as you would expect:
|
||
|
|
||
|
```javascript
|
||
|
assert.equal(qs.stringify({ a: 'b' }), 'a=b');
|
||
|
assert.equal(qs.stringify({ a: { b: 'c' } }), 'a%5Bb%5D=c');
|
||
|
```
|
||
|
|
||
|
This encoding can be disabled by setting the `encode` option to `false`:
|
||
|
|
||
|
```javascript
|
||
|
var unencoded = qs.stringify({ a: { b: 'c' } }, { encode: false });
|
||
|
assert.equal(unencoded, 'a[b]=c');
|
||
|
```
|
||
|
|
||
|
Encoding can be disabled for keys by setting the `encodeValuesOnly` option to `true`:
|
||
|
```javascript
|
||
|
var encodedValues = qs.stringify(
|
||
|
{ a: 'b', c: ['d', 'e=f'], f: [['g'], ['h']] },
|
||
|
{ encodeValuesOnly: true }
|
||
|
);
|
||
|
assert.equal(encodedValues,'a=b&c[0]=d&c[1]=e%3Df&f[0][0]=g&f[1][0]=h');
|
||
|
```
|
||
|
|
||
|
This encoding can also be replaced by a custom encoding method set as `encoder` option:
|
||
|
|
||
|
```javascript
|
||
|
var encoded = qs.stringify({ a: { b: 'c' } }, { encoder: function (str) {
|
||
|
// Passed in values `a`, `b`, `c`
|
||
|
return // Return encoded string
|
||
|
}})
|
||
|
```
|
||
|
|
||
|
_(Note: the `encoder` option does not apply if `encode` is `false`)_
|
||
|
|
||
|
Analogue to the `encoder` there is a `decoder` option for `parse` to override decoding of properties and values:
|
||
|
|
||
|
```javascript
|
||
|
var decoded = qs.parse('x=z', { decoder: function (str) {
|
||
|
// Passed in values `x`, `z`
|
||
|
return // Return decoded string
|
||
|
}})
|
||
|
```
|
||
|
|
||
|
You can encode keys and values using different logic by using the type argument provided to the encoder:
|
||
|
|
||
|
```javascript
|
||
|
var encoded = qs.stringify({ a: { b: 'c' } }, { encoder: function (str, defaultEncoder, charset, type) {
|
||
|
if (type === 'key') {
|
||
|
return // Encoded key
|
||
|
} else if (type === 'value') {
|
||
|
return // Encoded value
|
||
|
}
|
||
|
}})
|
||
|
```
|
||
|
|
||
|
The type argument is also provided to the decoder:
|
||
|
|
||
|
```javascript
|
||
|
var decoded = qs.parse('x=z', { decoder: function (str, defaultDecoder, charset, type) {
|
||
|
if (type === 'key') {
|
||
|
return // Decoded key
|
||
|
} else if (type === 'value') {
|
||
|
return // Decoded value
|
||
|
}
|
||
|
}})
|
||
|
```
|
||
|
|
||
|
Examples beyond this point will be shown as though the output is not URI encoded for clarity.
|
||
|
Please note that the return values in these cases *will* be URI encoded during real usage.
|
||
|
|
||
|
When arrays are stringified, they follow the `arrayFormat` option, which defaults to `indices`:
|
||
|
|
||
|
```javascript
|
||
|
qs.stringify({ a: ['b', 'c', 'd'] });
|
||
|
// 'a[0]=b&a[1]=c&a[2]=d'
|
||
|
```
|
||
|
|
||
|
You may override this by setting the `indices` option to `false`, or to be more explicit, the `arrayFormat` option to `repeat`:
|
||
|
|
||
|
```javascript
|
||
|
qs.stringify({ a: ['b', 'c', 'd'] }, { indices: false });
|
||
|
// 'a=b&a=c&a=d'
|
||
|
```
|
||
|
|
||
|
You may use the `arrayFormat` option to specify the format of the output array:
|
||
|
|
||
|
```javascript
|
||
|
qs.stringify({ a: ['b', 'c'] }, { arrayFormat: 'indices' })
|
||
|
// 'a[0]=b&a[1]=c'
|
||
|
qs.stringify({ a: ['b', 'c'] }, { arrayFormat: 'brackets' })
|
||
|
// 'a[]=b&a[]=c'
|
||
|
qs.stringify({ a: ['b', 'c'] }, { arrayFormat: 'repeat' })
|
||
|
// 'a=b&a=c'
|
||
|
qs.stringify({ a: ['b', 'c'] }, { arrayFormat: 'comma' })
|
||
|
// 'a=b,c'
|
||
|
```
|
||
|
|
||
|
Note: when using `arrayFormat` set to `'comma'`, you can also pass the `commaRoundTrip` option set to `true` or `false`, to append `[]` on single-item arrays, so that they can round trip through a parse.
|
||
|
|
||
|
When objects are stringified, by default they use bracket notation:
|
||
|
|
||
|
```javascript
|
||
|
qs.stringify({ a: { b: { c: 'd', e: 'f' } } });
|
||
|
// 'a[b][c]=d&a[b][e]=f'
|
||
|
```
|
||
|
|
||
|
You may override this to use dot notation by setting the `allowDots` option to `true`:
|
||
|
|
||
|
```javascript
|
||
|
qs.stringify({ a: { b: { c: 'd', e: 'f' } } }, { allowDots: true });
|
||
|
// 'a.b.c=d&a.b.e=f'
|
||
|
```
|
||
|
|
||
|
You may encode the dot notation in the keys of object with option `encodeDotInKeys` by setting it to `true`:
|
||
|
Note: it implies `allowDots`, so `stringify` will error if you set `decodeDotInKeys` to `true`, and `allowDots` to `false`.
|
||
|
Caveat: when `encodeValuesOnly` is `true` as well as `encodeDotInKeys`, only dots in keys and nothing else will be encoded.
|
||
|
```javascript
|
||
|
qs.stringify({ "name.obj": { "first": "John", "last": "Doe" } }, { allowDots: true, encodeDotInKeys: true })
|
||
|
// 'name%252Eobj.first=John&name%252Eobj.last=Doe'
|
||
|
```
|
||
|
|
||
|
You may allow empty array values by setting the `allowEmptyArrays` option to `true`:
|
||
|
```javascript
|
||
|
qs.stringify({ foo: [], bar: 'baz' }, { allowEmptyArrays: true });
|
||
|
// 'foo[]&bar=baz'
|
||
|
```
|
||
|
|
||
|
Empty strings and null values will omit the value, but the equals sign (=) remains in place:
|
||
|
|
||
|
```javascript
|
||
|
assert.equal(qs.stringify({ a: '' }), 'a=');
|
||
|
```
|
||
|
|
||
|
Key with no values (such as an empty object or array) will return nothing:
|
||
|
|
||
|
```javascript
|
||
|
assert.equal(qs.stringify({ a: [] }), '');
|
||
|
assert.equal(qs.stringify({ a: {} }), '');
|
||
|
assert.equal(qs.stringify({ a: [{}] }), '');
|
||
|
assert.equal(qs.stringify({ a: { b: []} }), '');
|
||
|
assert.equal(qs.stringify({ a: { b: {}} }), '');
|
||
|
```
|
||
|
|
||
|
Properties that are set to `undefined` will be omitted entirely:
|
||
|
|
||
|
```javascript
|
||
|
assert.equal(qs.stringify({ a: null, b: undefined }), 'a=');
|
||
|
```
|
||
|
|
||
|
The query string may optionally be prepended with a question mark:
|
||
|
|
||
|
```javascript
|
||
|
assert.equal(qs.stringify({ a: 'b', c: 'd' }, { addQueryPrefix: true }), '?a=b&c=d');
|
||
|
```
|
||
|
|
||
|
The delimiter may be overridden with stringify as well:
|
||
|
|
||
|
```javascript
|
||
|
assert.equal(qs.stringify({ a: 'b', c: 'd' }, { delimiter: ';' }), 'a=b;c=d');
|
||
|
```
|
||
|
|
||
|
If you only want to override the serialization of `Date` objects, you can provide a `serializeDate` option:
|
||
|
|
||
|
```javascript
|
||
|
var date = new Date(7);
|
||
|
assert.equal(qs.stringify({ a: date }), 'a=1970-01-01T00:00:00.007Z'.replace(/:/g, '%3A'));
|
||
|
assert.equal(
|
||
|
qs.stringify({ a: date }, { serializeDate: function (d) { return d.getTime(); } }),
|
||
|
'a=7'
|
||
|
);
|
||
|
```
|
||
|
|
||
|
You may use the `sort` option to affect the order of parameter keys:
|
||
|
|
||
|
```javascript
|
||
|
function alphabeticalSort(a, b) {
|
||
|
return a.localeCompare(b);
|
||
|
}
|
||
|
assert.equal(qs.stringify({ a: 'c', z: 'y', b : 'f' }, { sort: alphabeticalSort }), 'a=c&b=f&z=y');
|
||
|
```
|
||
|
|
||
|
Finally, you can use the `filter` option to restrict which keys will be included in the stringified output.
|
||
|
If you pass a function, it will be called for each key to obtain the replacement value.
|
||
|
Otherwise, if you pass an array, it will be used to select properties and array indices for stringification:
|
||
|
|
||
|
```javascript
|
||
|
function filterFunc(prefix, value) {
|
||
|
if (prefix == 'b') {
|
||
|
// Return an `undefined` value to omit a property.
|
||
|
return;
|
||
|
}
|
||
|
if (prefix == 'e[f]') {
|
||
|
return value.getTime();
|
||
|
}
|
||
|
if (prefix == 'e[g][0]') {
|
||
|
return value * 2;
|
||
|
}
|
||
|
return value;
|
||
|
}
|
||
|
qs.stringify({ a: 'b', c: 'd', e: { f: new Date(123), g: [2] } }, { filter: filterFunc });
|
||
|
// 'a=b&c=d&e[f]=123&e[g][0]=4'
|
||
|
qs.stringify({ a: 'b', c: 'd', e: 'f' }, { filter: ['a', 'e'] });
|
||
|
// 'a=b&e=f'
|
||
|
qs.stringify({ a: ['b', 'c', 'd'], e: 'f' }, { filter: ['a', 0, 2] });
|
||
|
// 'a[0]=b&a[2]=d'
|
||
|
```
|
||
|
|
||
|
You could also use `filter` to inject custom serialization for user defined types.
|
||
|
Consider you're working with some api that expects query strings of the format for ranges:
|
||
|
|
||
|
```
|
||
|
https://domain.com/endpoint?range=30...70
|
||
|
```
|
||
|
|
||
|
For which you model as:
|
||
|
|
||
|
```javascript
|
||
|
class Range {
|
||
|
constructor(from, to) {
|
||
|
this.from = from;
|
||
|
this.to = to;
|
||
|
}
|
||
|
}
|
||
|
```
|
||
|
|
||
|
You could _inject_ a custom serializer to handle values of this type:
|
||
|
|
||
|
```javascript
|
||
|
qs.stringify(
|
||
|
{
|
||
|
range: new Range(30, 70),
|
||
|
},
|
||
|
{
|
||
|
filter: (prefix, value) => {
|
||
|
if (value instanceof Range) {
|
||
|
return `${value.from}...${value.to}`;
|
||
|
}
|
||
|
// serialize the usual way
|
||
|
return value;
|
||
|
},
|
||
|
}
|
||
|
);
|
||
|
// range=30...70
|
||
|
```
|
||
|
|
||
|
### Handling of `null` values
|
||
|
|
||
|
By default, `null` values are treated like empty strings:
|
||
|
|
||
|
```javascript
|
||
|
var withNull = qs.stringify({ a: null, b: '' });
|
||
|
assert.equal(withNull, 'a=&b=');
|
||
|
```
|
||
|
|
||
|
Parsing does not distinguish between parameters with and without equal signs.
|
||
|
Both are converted to empty strings.
|
||
|
|
||
|
```javascript
|
||
|
var equalsInsensitive = qs.parse('a&b=');
|
||
|
assert.deepEqual(equalsInsensitive, { a: '', b: '' });
|
||
|
```
|
||
|
|
||
|
To distinguish between `null` values and empty strings use the `strictNullHandling` flag. In the result string the `null`
|
||
|
values have no `=` sign:
|
||
|
|
||
|
```javascript
|
||
|
var strictNull = qs.stringify({ a: null, b: '' }, { strictNullHandling: true });
|
||
|
assert.equal(strictNull, 'a&b=');
|
||
|
```
|
||
|
|
||
|
To parse values without `=` back to `null` use the `strictNullHandling` flag:
|
||
|
|
||
|
```javascript
|
||
|
var parsedStrictNull = qs.parse('a&b=', { strictNullHandling: true });
|
||
|
assert.deepEqual(parsedStrictNull, { a: null, b: '' });
|
||
|
```
|
||
|
|
||
|
To completely skip rendering keys with `null` values, use the `skipNulls` flag:
|
||
|
|
||
|
```javascript
|
||
|
var nullsSkipped = qs.stringify({ a: 'b', c: null}, { skipNulls: true });
|
||
|
assert.equal(nullsSkipped, 'a=b');
|
||
|
```
|
||
|
|
||
|
If you're communicating with legacy systems, you can switch to `iso-8859-1` using the `charset` option:
|
||
|
|
||
|
```javascript
|
||
|
var iso = qs.stringify({ æ: 'æ' }, { charset: 'iso-8859-1' });
|
||
|
assert.equal(iso, '%E6=%E6');
|
||
|
```
|
||
|
|
||
|
Characters that don't exist in `iso-8859-1` will be converted to numeric entities, similar to what browsers do:
|
||
|
|
||
|
```javascript
|
||
|
var numeric = qs.stringify({ a: '☺' }, { charset: 'iso-8859-1' });
|
||
|
assert.equal(numeric, 'a=%26%239786%3B');
|
||
|
```
|
||
|
|
||
|
You can use the `charsetSentinel` option to announce the character by including an `utf8=✓` parameter with the proper encoding if the checkmark, similar to what Ruby on Rails and others do when submitting forms.
|
||
|
|
||
|
```javascript
|
||
|
var sentinel = qs.stringify({ a: '☺' }, { charsetSentinel: true });
|
||
|
assert.equal(sentinel, 'utf8=%E2%9C%93&a=%E2%98%BA');
|
||
|
|
||
|
var isoSentinel = qs.stringify({ a: 'æ' }, { charsetSentinel: true, charset: 'iso-8859-1' });
|
||
|
assert.equal(isoSentinel, 'utf8=%26%2310003%3B&a=%E6');
|
||
|
```
|
||
|
|
||
|
### Dealing with special character sets
|
||
|
|
||
|
By default the encoding and decoding of characters is done in `utf-8`, and `iso-8859-1` support is also built in via the `charset` parameter.
|
||
|
|
||
|
If you wish to encode querystrings to a different character set (i.e.
|
||
|
[Shift JIS](https://en.wikipedia.org/wiki/Shift_JIS)) you can use the
|
||
|
[`qs-iconv`](https://github.com/martinheidegger/qs-iconv) library:
|
||
|
|
||
|
```javascript
|
||
|
var encoder = require('qs-iconv/encoder')('shift_jis');
|
||
|
var shiftJISEncoded = qs.stringify({ a: 'こんにちは!' }, { encoder: encoder });
|
||
|
assert.equal(shiftJISEncoded, 'a=%82%B1%82%F1%82%C9%82%BF%82%CD%81I');
|
||
|
```
|
||
|
|
||
|
This also works for decoding of query strings:
|
||
|
|
||
|
```javascript
|
||
|
var decoder = require('qs-iconv/decoder')('shift_jis');
|
||
|
var obj = qs.parse('a=%82%B1%82%F1%82%C9%82%BF%82%CD%81I', { decoder: decoder });
|
||
|
assert.deepEqual(obj, { a: 'こんにちは!' });
|
||
|
```
|
||
|
|
||
|
### RFC 3986 and RFC 1738 space encoding
|
||
|
|
||
|
RFC3986 used as default option and encodes ' ' to *%20* which is backward compatible.
|
||
|
In the same time, output can be stringified as per RFC1738 with ' ' equal to '+'.
|
||
|
|
||
|
```
|
||
|
assert.equal(qs.stringify({ a: 'b c' }), 'a=b%20c');
|
||
|
assert.equal(qs.stringify({ a: 'b c' }, { format : 'RFC3986' }), 'a=b%20c');
|
||
|
assert.equal(qs.stringify({ a: 'b c' }, { format : 'RFC1738' }), 'a=b+c');
|
||
|
```
|
||
|
|
||
|
## Security
|
||
|
|
||
|
Please email [@ljharb](https://github.com/ljharb) or see https://tidelift.com/security if you have a potential security vulnerability to report.
|
||
|
|
||
|
## qs for enterprise
|
||
|
|
||
|
Available as part of the Tidelift Subscription
|
||
|
|
||
|
The maintainers of qs and thousands of other packages are working with Tidelift to deliver commercial support and maintenance for the open source dependencies you use to build your applications.
|
||
|
Save time, reduce risk, and improve code health, while paying the maintainers of the exact dependencies you use.
|
||
|
[Learn more.](https://tidelift.com/subscription/pkg/npm-qs?utm_source=npm-qs&utm_medium=referral&utm_campaign=enterprise&utm_term=repo)
|
||
|
|
||
|
[package-url]: https://npmjs.org/package/qs
|
||
|
[npm-version-svg]: https://versionbadg.es/ljharb/qs.svg
|
||
|
[deps-svg]: https://david-dm.org/ljharb/qs.svg
|
||
|
[deps-url]: https://david-dm.org/ljharb/qs
|
||
|
[dev-deps-svg]: https://david-dm.org/ljharb/qs/dev-status.svg
|
||
|
[dev-deps-url]: https://david-dm.org/ljharb/qs#info=devDependencies
|
||
|
[npm-badge-png]: https://nodei.co/npm/qs.png?downloads=true&stars=true
|
||
|
[license-image]: https://img.shields.io/npm/l/qs.svg
|
||
|
[license-url]: LICENSE
|
||
|
[downloads-image]: https://img.shields.io/npm/dm/qs.svg
|
||
|
[downloads-url]: https://npm-stat.com/charts.html?package=qs
|
||
|
[codecov-image]: https://codecov.io/gh/ljharb/qs/branch/main/graphs/badge.svg
|
||
|
[codecov-url]: https://app.codecov.io/gh/ljharb/qs/
|
||
|
[actions-image]: https://img.shields.io/endpoint?url=https://github-actions-badge-u3jn4tfpocch.runkit.sh/ljharb/qs
|
||
|
[actions-url]: https://github.com/ljharb/qs/actions
|
||
|
|
||
|
## Acknowledgements
|
||
|
|
||
|
qs logo by [NUMI](https://github.com/numi-hq/open-design):
|
||
|
|
||
|
[<img src="https://raw.githubusercontent.com/numi-hq/open-design/main/assets/numi-lockup.png" alt="NUMI Logo" style="width: 200px;"/>](https://numi.tech/?ref=qs)
|