116 lines
2.8 KiB
Markdown
116 lines
2.8 KiB
Markdown
go-cid
|
|
==================
|
|
|
|
[](http://ipn.io)
|
|
[](http://ipfs.io/)
|
|
[](http://webchat.freenode.net/?channels=%23ipfs)
|
|
[](https://github.com/RichardLitt/standard-readme)
|
|
[](https://godoc.org/github.com/ipfs/go-cid)
|
|
[](https://coveralls.io/github/ipfs/go-cid?branch=master)
|
|
[](https://travis-ci.org/ipfs/go-cid)
|
|
|
|
> A package to handle content IDs in Go.
|
|
|
|
This is an implementation in Go of the [CID spec](https://github.com/ipld/cid).
|
|
It is used in `go-ipfs` and related packages to refer to a typed hunk of data.
|
|
|
|
## Lead Maintainer
|
|
|
|
[Eric Myhre](https://github.com/warpfork)
|
|
|
|
## Table of Contents
|
|
|
|
- [Install](#install)
|
|
- [Usage](#usage)
|
|
- [API](#api)
|
|
- [Contribute](#contribute)
|
|
- [License](#license)
|
|
|
|
## Install
|
|
|
|
`go-cid` is a standard Go module which can be installed with:
|
|
|
|
```sh
|
|
go get github.com/ipfs/go-cid
|
|
```
|
|
|
|
## Usage
|
|
|
|
### Running tests
|
|
|
|
Run tests with `go test` from the directory root
|
|
|
|
```sh
|
|
go test
|
|
```
|
|
|
|
### Examples
|
|
|
|
#### Parsing string input from users
|
|
|
|
```go
|
|
// Create a cid from a marshaled string
|
|
c, err := cid.Decode("bafzbeigai3eoy2ccc7ybwjfz5r3rdxqrinwi4rwytly24tdbh6yk7zslrm")
|
|
if err != nil {...}
|
|
|
|
fmt.Println("Got CID: ", c)
|
|
```
|
|
|
|
#### Creating a CID from scratch
|
|
|
|
```go
|
|
|
|
import (
|
|
cid "github.com/ipfs/go-cid"
|
|
mc "github.com/multiformats/go-multicodec"
|
|
mh "github.com/multiformats/go-multihash"
|
|
)
|
|
|
|
// Create a cid manually by specifying the 'prefix' parameters
|
|
pref := cid.Prefix{
|
|
Version: 1,
|
|
Codec: mc.Raw,
|
|
MhType: mh.SHA2_256,
|
|
MhLength: -1, // default length
|
|
}
|
|
|
|
// And then feed it some data
|
|
c, err := pref.Sum([]byte("Hello World!"))
|
|
if err != nil {...}
|
|
|
|
fmt.Println("Created CID: ", c)
|
|
```
|
|
|
|
#### Check if two CIDs match
|
|
|
|
```go
|
|
// To test if two cid's are equivalent, be sure to use the 'Equals' method:
|
|
if c1.Equals(c2) {
|
|
fmt.Println("These two refer to the same exact data!")
|
|
}
|
|
```
|
|
|
|
#### Check if some data matches a given CID
|
|
|
|
```go
|
|
// To check if some data matches a given cid,
|
|
// Get your CIDs prefix, and use that to sum the data in question:
|
|
other, err := c.Prefix().Sum(mydata)
|
|
if err != nil {...}
|
|
|
|
if !c.Equals(other) {
|
|
fmt.Println("This data is different.")
|
|
}
|
|
|
|
```
|
|
|
|
## Contribute
|
|
|
|
PRs are welcome!
|
|
|
|
Small note: If editing the Readme, please conform to the [standard-readme](https://github.com/RichardLitt/standard-readme) specification.
|
|
|
|
## License
|
|
|
|
MIT © Jeromy Johnson
|