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fixed vendor fetch
2018-08-07 22:24:46 +03:00
# NUID
Faster point in polygon / GeoJSON updates The big change is that the GeoJSON package has been completely rewritten to fix a few of geometry calculation bugs, increase performance, and to better follow the GeoJSON spec RFC 7946. GeoJSON updates - A LineString now requires at least two points. - All json members, even foreign, now persist with the object. - The bbox member persists too but is no longer used for geometry calculations. This is change in behavior. Previously Tile38 would treat the bbox as the object's physical rectangle. - Corrections to geometry intersects and within calculations. Faster spatial queries - The performance of Point-in-polygon and object intersect operations are greatly improved for complex polygons and line strings. It went from O(n) to roughly O(log n). - The same for all collection types with many children, including FeatureCollection, GeometryCollection, MultiPoint, MultiLineString, and MultiPolygon. Codebase changes - The pkg directory has been renamed to internal - The GeoJSON internal package has been moved to a seperate repo at https://github.com/tidwall/geojson. It's now vendored. Please look out for higher memory usage for datasets using complex shapes. A complex shape is one that has 64 or more points. For these shapes it's expected that there will be increase of least 54 bytes per point.
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[![License MIT](https://img.shields.io/npm/l/express.svg)](http://opensource.org/licenses/MIT)
fixed vendor fetch
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[![ReportCard](http://goreportcard.com/badge/nats-io/nuid)](http://goreportcard.com/report/nats-io/nuid)
[![Build Status](https://travis-ci.org/nats-io/nuid.svg?branch=master)](http://travis-ci.org/nats-io/nuid)
[![Release](https://img.shields.io/badge/release-v1.0.0-1eb0fc.svg)](https://github.com/nats-io/nuid/releases/tag/v1.0.0)
[![GoDoc](http://godoc.org/github.com/nats-io/nuid?status.png)](http://godoc.org/github.com/nats-io/nuid)
[![Coverage Status](https://coveralls.io/repos/github/nats-io/nuid/badge.svg?branch=master)](https://coveralls.io/github/nats-io/nuid?branch=master)
A highly performant unique identifier generator.
## Installation
Use the `go` command:
$ go get github.com/nats-io/nuid
## Basic Usage
```go
// Utilize the global locked instance
nuid := nuid.Next()
// Create an instance, these are not locked.
n := nuid.New()
nuid = n.Next()
// Generate a new crypto/rand seeded prefix.
// Generally not needed, happens automatically.
n.RandomizePrefix()
```
## Performance
NUID needs to be very fast to generate and be truly unique, all while being entropy pool friendly.
NUID uses 12 bytes of crypto generated data (entropy draining), and 10 bytes of pseudo-random
sequential data that increments with a pseudo-random increment.
Faster point in polygon / GeoJSON updates The big change is that the GeoJSON package has been completely rewritten to fix a few of geometry calculation bugs, increase performance, and to better follow the GeoJSON spec RFC 7946. GeoJSON updates - A LineString now requires at least two points. - All json members, even foreign, now persist with the object. - The bbox member persists too but is no longer used for geometry calculations. This is change in behavior. Previously Tile38 would treat the bbox as the object's physical rectangle. - Corrections to geometry intersects and within calculations. Faster spatial queries - The performance of Point-in-polygon and object intersect operations are greatly improved for complex polygons and line strings. It went from O(n) to roughly O(log n). - The same for all collection types with many children, including FeatureCollection, GeometryCollection, MultiPoint, MultiLineString, and MultiPolygon. Codebase changes - The pkg directory has been renamed to internal - The GeoJSON internal package has been moved to a seperate repo at https://github.com/tidwall/geojson. It's now vendored. Please look out for higher memory usage for datasets using complex shapes. A complex shape is one that has 64 or more points. For these shapes it's expected that there will be increase of least 54 bytes per point.
2018-10-11 00:25:40 +03:00
Total length of a NUID string is 22 bytes of base 36 ascii text, so 36^22 or
17324272922341479351919144385642496 possibilities.
fixed vendor fetch
2018-08-07 22:24:46 +03:00
NUID can generate identifiers as fast as 60ns, or ~16 million per second. There is an associated
benchmark you can use to test performance on your own hardware.
## License
Faster point in polygon / GeoJSON updates The big change is that the GeoJSON package has been completely rewritten to fix a few of geometry calculation bugs, increase performance, and to better follow the GeoJSON spec RFC 7946. GeoJSON updates - A LineString now requires at least two points. - All json members, even foreign, now persist with the object. - The bbox member persists too but is no longer used for geometry calculations. This is change in behavior. Previously Tile38 would treat the bbox as the object's physical rectangle. - Corrections to geometry intersects and within calculations. Faster spatial queries - The performance of Point-in-polygon and object intersect operations are greatly improved for complex polygons and line strings. It went from O(n) to roughly O(log n). - The same for all collection types with many children, including FeatureCollection, GeometryCollection, MultiPoint, MultiLineString, and MultiPolygon. Codebase changes - The pkg directory has been renamed to internal - The GeoJSON internal package has been moved to a seperate repo at https://github.com/tidwall/geojson. It's now vendored. Please look out for higher memory usage for datasets using complex shapes. A complex shape is one that has 64 or more points. For these shapes it's expected that there will be increase of least 54 bytes per point.
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(The MIT License)
Copyright (c) 2016 Apcera Inc.
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to
deal in the Software without restriction, including without limitation the
rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
sell copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
IN THE SOFTWARE.