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A python port of the JavaScript hashids implementation. It generates YouTube-like hashes from one or many numbers. Use hashids when you do not want to expose your database ids to the user. Website: http://www.hashids.org/

Compatibility

hashids is tested with python 2.6, 2.7, 3.2, 3.3 and 3.4. PyPy and PyPy 3 work as well.

https://travis-ci.org/davidaurelio/hashids-python.svg?branch=master

Compatibility with the JavaScript implementation

hashids/JavaScript

hashids/Python

v0.1.x

v0.8.x

v0.3.x and v1.0.x

v1.0.2+

The JavaScript implementation produces different hashes in versions 0.1.x and 0.3.x. For compatibility with the older 0.1.x version install hashids 0.8.4 from pip, otherwise the newest hashids.

Installation

Install the module from PyPI, e. g. with pip:

pip install hashids
pip install hashids==0.8.4 # for compatibility with hashids.js 0.1.x

Run the tests

The tests are written with pytest. The pytest module has to be installed.

python -m pytest

Usage

Import the constructor from the hashids module:

from hashids import Hashids
hashids = Hashids()

Basic Usage

Encode a single integer:

hashid = hashids.encode(123) # 'Mj3'

Decode a hash:

ints = hashids.decode('xoz') # (456,)

To encode several integers, pass them all at once:

hashid = hashids.encode(123, 456, 789) # 'El3fkRIo3'

Decoding is done the same way:

ints = hashids.decode('1B8UvJfXm') # (517, 729, 185)

Using A Custom Salt

Hashids supports salting hashes by accepting a salt value. If you don’t want others to decode your hashes, provide a unique string to the constructor.

hashids = Hashids(salt='this is my salt 1')
hashid = hashids.encode(123) # 'nVB'

The generated hash changes whenever the salt is changed:

hashids = Hashids(salt='this is my salt 2')
hashid = hashids.encode(123) # 'ojK'

A salt string between 6 and 32 characters provides decent randomization.

Controlling Hash Length

By default, hashes are going to be the shortest possible. One reason you might want to increase the hash length is to obfuscate how large the integer behind the hash is.

This is done by passing the minimum hash length to the constructor. Hashes are padded with extra characters to make them seem longer.

hashids = Hashids(min_length=16)
hashid = hashids.encode(1) # '4q2VolejRejNmGQB'

Using A Custom Alphabet

It’s possible to set a custom alphabet for your hashes. The default alphabet is 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890'.

To have only lowercase letters in your hashes, pass in the following custom alphabet:

hashids = Hashids(alphabet='abcdefghijklmnopqrstuvwxyz')
hashid = hashids.encode(123456789) # 'kekmyzyk'

A custom alphabet must contain at least 16 characters.

Randomness

The primary purpose of hashids is to obfuscate ids. It’s not meant or tested to be used for security purposes or compression. Having said that, this algorithm does try to make these hashes unguessable and unpredictable:

Repeating numbers

There are no repeating patterns that might show that there are 4 identical numbers in the hash:

hashids = Hashids("this is my salt")
hashids.encode(5, 5, 5, 5) # '1Wc8cwcE'

The same is valid for incremented numbers:

hashids.encode(1, 2, 3, 4, 5, 6, 7, 8, 9, 10) # 'kRHnurhptKcjIDTWC3sx'

hashids.encode(1) # 'NV'
hashids.encode(2) # '6m'
hashids.encode(3) # 'yD'
hashids.encode(4) # '2l'
hashids.encode(5) # 'rD'

Curses! #$%@

This code was written with the intent of placing generated hashes in visible places – like the URL. Which makes it unfortunate if generated hashes accidentally formed a bad word.

Therefore, the algorithm tries to avoid generating most common English curse words by never placing the following letters next to each other: c, C, s, S, f, F, h, H, u, U, i, I, t, T.

License

MIT license, see the LICENSE file. You can use hashids in open source projects and commercial products.

Metadata

Release files for hashids 1.0.3

For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.

Source distribution (sdist)

Source distribution for hashids 1.0.3
File Size Uploaded
hashids-1.0.3.tar.gz 7.6 kB Details

Release files / hashids-1.0.3.tar.gz

Download URL hashids-1.0.3.tar.gz
Size 7.6 kB
Tags Source
SHA-256 checksum
How to use checksums
94fd54cc286b490a688275af14ed4aa0187dc5e7110ba4148fd3cbe8408df548
BLAKE2b-256 checksum
How to use checksums
70fbb8babba4e660cd706f1a609bd20feb81c4437b2d8489b8b1cbc0d9c453af
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1.3.1

2 release files

1.3.0

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1.2.0

1 release file

1.1.0

1 release file

This release

1.0.3 This release

1 release file

1.0.2

1 release file

1.0.1

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1.0.0

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0.8.4

1 release file

0.8.3

1 release file

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