TakerTAO Testchain

This tool will help you set up a local testchain and deploy the contracts you need to work with Taker apps.

This branch, tao.js, is configured with the contracts needed for the Tao.js library.

Installation and requirements

Requires Seth, Nix, Node.js and Bash.

Run npm install or yarn install to install Ganache.

Typical usage

scripts/launch -s default --fast

Usage

Run scripts/launch.

If run with no arguments, it will start Ganache at 127.0.0.1:2000 with the chain data it finds in var/chaindata, and run until killed with Ctrl-C.

If var/chaindata does not exist, and the --reset-chaindata argument is not present, the default snapshot will be used to create it.

Once the deployment is complete, you will find the list of contract addresses in the out/addresses.json file.

Creating a new snapshot

If you want to add new contracts to the deployment scripts and create a new snapshot from the resulting deployment, you can run the following series of commands:

scripts/launch --reset-chaindata -d --deploy-scd-only -u
scripts/create-snapshot scd-only --force
scripts/launch -s scd-only -d --deploy-mcd-only -u
scripts/create-snapshot default --force

The above series creates a separate snapshot with only the scd deployment simply to make updating mcd-specific code easier and faster. If this isn't relevant to your use case, you can omit those steps and run:

scripts/launch --reset-chaindata -d -u
scripts/create-snapshot your-snapshot-name

Snapshot names are arbitrary, so in the above case, you could create another snapshot if necessary. The --force flag in the first example is only required if you're overwriting an existing snapshot.

Also note that -u skips the submodule update, and can be omitted if you need to update before running the scripts.

If you run the scd and mcd scripts separately, be careful to only include --reset-chaindata in the former. The mcd scripts depend on some of the chaindata from the scd scripts, and will fail without it. If you're running them both at the same time, like in the second example above, you can include it without causing any failures.

Options

• -s, --snapshot: Optional. This should match the name of a folder under the snapshots folder. This will be copied to var/chaindata, overwriting anything there.

• -d, --deploy: Optional. If set, scripts/deploy will be run once Ganache is set up, to deploy contracts to the test chain.

• --fast: Skip git submodule update and skip running dapp build for dapps that are already built. This is accomplished by setting the SKIP_BUILD_IF_ALREADY_BUILT environment variable, so the dapp build scripts must be written (or modified; see the use of sed_inplace in scripts/deploy) to support it.

• --reset-chaindata: Start the testchain with no data.

• -u, --skip-update: Skip the git submodule updates, but still run dapp build on the contracts.

• -p, --port: Start Ganache on a different port.

• --throw-revert: Have Ganache throw an exception whenever a transaction is reverted.

• --ci: If this is set, all unrecognized arguments will be treated as a new command. This command will be run, and Ganache will exit afterward.

Deploying changes to contract code

When the deploy script is run, it copies ABI files and output addresses of deployment contracts to a file in out/ directory. These can be copied into the source code of applications working with the test chain as you see fit.

Creating new snapshots

Use scripts/create-snapshot NAME to copy the contents of var/chaindata into a new folder snapshots/NAME. Add --force if you want to replace an existing snapshot.

Recipe: rebuilding MCT

./scripts/launch -s scd-only --deploy --deploy-mct-only

This starts with a snapshot of all the SCT contracts, and then redeploys all the MCT contracts on top of that snapshot. Edit scripts/deploy-mct to tweak the build parameters or add to it.