Chain Core is software designed to operate and connect to highly scalable permissioned blockchain networks conforming to the Chain Protocol. Each network maintains a cryptographically-secured transaction log, known as a blockchain, which allows partipicants to define, issue, and transfer digital assets on a multi-asset shared ledger. Digital assets share a common, interoperable format and can represent any units of value that are guaranteed by a trusted issuer — such as currencies, bonds, securities, IOUs, or loyalty points. Each Chain Core holds a copy of the ledger and independently validates each update, or “block,” while a federation of block signers ensures global consistency of the ledger.
Chain Core Developer Edition is a free, downloadable version of Chain Core that is open source and licensed under the AGPL. Individuals and organizations use Chain Core Developer Edition to learn, experiment, and build prototypes.
Chain Core Developer Edition can be run locally on Mac, Windows, or Linux to create a new blockchain network, connect to an existing blockchain network, or connect to the public Chain testnet, operated by Chain, Microsoft, and Cornell University’s IC3.
For more information about how to use Chain Core Developer Edition, see the docs: https://chain.com/docs
To install Chain Core Developer Edition on Mac, Windows, or Linux, please visit our downloads page.
Chain has adopted the code of conduct defined by the Contributor Covenant. It can be read in full here. This repository is the canonical source for Chain Core Developer Edition. Consequently, Chain engineers actively maintain this repository. If you are interested in contributing to this code base, please read our issue and pull request templates first.
- Go version 1.8, with $GOPATH set to your preferred directory
- Postgres (we suggest Postgres.app), along with the command line tools
- protoc 3.1.0 and protoc-gen-g, if you need to compile protos
- CMake 3.4 or later, to compile RocksDB and its dependencies
Set the CHAIN
environment variable, in .profile
in your home
directory, to point to the root of the Chain source code repo:
export CHAIN=$(go env GOPATH)/src/chain
You should also add $CHAIN/bin
to your path (as well as
$(go env GOPATH)/bin
, if it isn’t already):
PATH=$(go env GOPATH)/bin:$CHAIN/bin:$PATH
You might want to open a new terminal window to pick up the change.
Clone this repository to $CHAIN
:
$ git clone https://github.com/chain/chain $CHAIN
$ cd $CHAIN
You can build Chain Core using the build-cored-release
script.
The build product allows connections over HTTP, unauthenticated
requests from localhost, and the ability to reset the Chain Core.
build-cored-release
accepts a accepts a Git ref (branch, tag, or commit SHA)
from the chain repository and an output directory:
$ ./bin/build-cored-release chain-core-server-1.2.0 .
This will create two binaries in the current directory:
Set up the database:
$ createdb core
Start Chain Core:
$ ./cored
Access the dashboard:
$ open http://localhost:1999/
Run tests:
$ go test $(go list ./... | grep -v vendor)
There are four build tags that change the behavior of the resulting binary:
reset
: allows the core database to be reset through the apilocalhost_auth
: allows unauthenticated requests on the loopback device (localhost)no_mockhsm
: disables the MockHSM provided for developmenthttp_ok
: allows plain HTTP requestsinit_cluster
: automatically creates a single process cluster
The default build process creates a binary with three build tags enabled for a friendlier experience. To build from source with build tags, use the following command:
NOTE: when building from source, make sure to check out a specific tag to build. The
main
branch is not considered stable, and may contain in progress features or an inconsistent experience.
$ go build -tags 'http_ok localhost_auth init_cluster' chain/cmd/cored
$ go build chain/cmd/corectl
$ go run cmd/dumpschema/main.go
To add or update a Go dependency at import path x
, do the following:
Copy the code from the package's directory
to $CHAIN/vendor/x
. For example, to vendor the package
github.com/kr/pretty
, run
$ mkdir -p $CHAIN/vendor/github.com/kr
$ rm -r $CHAIN/vendor/github.com/kr/pretty
$ cp -r $(go list -f {{.Dir}} github.com/kr/pretty) $CHAIN/vendor/github.com/kr/pretty
$ rm -rf $CHAIN/vendor/github.com/kr/pretty/.git
(Note: don’t put a trailing slash (/
) on these paths.
It can change the behavior of cp and put the files
in the wrong place.)
In your commit message, include the commit hash of the upstream repo
for the dependency. (You can find this with git rev-parse HEAD
in
the upstream repo.) Also, make sure the upstream working tree is clean.
(Check with git status
.)
Chain Core Developer Edition is licensed under the terms of the GNU Affero General Public License Version 3 (AGPL).
The Chain Java SDK (/sdk/java
) is licensed under the terms of the
Apache License Version 2.0.