concordia/docker/README.md

# Concordia Dockerized

This page provides information about the provided docker images, their configuration and supported deployment
strategies.

TLDR: head down to [Putting it all together/Scripts](#piat-mkfile-targets) for a quick setup.

## Services

Concordia requires at the minimum two services to work, a blockchain and a rendezvous server.

Additionally, the Concordia application code must be provided to the user. Currently, the only way of distributing the
application code is via a webserver as a web application.

### Ganache

Ganache is a personal blockchain software used during development. It is a very convenient way of developing and testing
dApps. More information can be found in the project's [website](https://www.trufflesuite.com/ganache).

Note that any other Ethereum compliant blockchain can be used.

### Rendezvous

Concordia uses a distributed database to store forum data. A rendezvous server is needed in order for users to discover
peers in the network and get access to the data.

### Application

The Concordia application is a React app that handles interactions with the contracts and the distributed database used.

## Docker images

This repository provides docker images to easily setup (and destroy) instances of all required services Concordia.
Furthermore, we provide an image that builds the contracts and handles their migration to the blockchain in use.

### Ganache

The Dockerfile is provided in the path `./ganache`. The image makes use of the environment variables described
bellow.

| Environment variable | Default value | Usage |
| --- | --- | --- |
| ACCOUNTS_NUMBER | 10 | Set the number of accounts generated |
| ACCOUNTS_ETHER | 100 | Set the amount of ETH assigned to each account |
| MNEMONIC | NaN | The mnemonic phrase sued as a seed for deterministic account generation |
| HOST | 0.0.0.0 | The hostname to listen on |
| PORT | 8545 | The port to listen on |
| NETWORK_ID | 5778 | The network id used to identify ganache |

Note that the Ganache instance running inside the container will save the generated blockchain keys in the path
`/home/ganache_keys/keys.json`. If you need to access the keys (eg for getting a private key and importing in Metamask)
you can mount a volume to this path to have easier access.

Also, the database used by Ganache for storing blockchain information is placed in the path `/home/ganache_db/`. You can
maintain the blockchain state between runs by mounting a volume to the database path. To do that, add the docker flag 
`-v host/absolute/path/to/ganache_db:/home/ganache_db`.

### Rendezvous

The rendezvous server used here is `js-libp2p-webrtc-star`. The server listens on port 9090. More information can be
found on the github page of the project [here](https://github.com/libp2p/js-libp2p-webrtc-star).

### Contracts

This is a provision system that compiles and deploys the contracts to any Ethereum blockchain.

A Dockerfile is provided in the path `./concordia-contracts` that will build the contracts used by Concordia and
handle their deployment to any Ethereum network defined using env-vars upon container run. Dockerfile contains three
useful stages, described in the table bellow.

| Stage name | Entrypoint | Usage |
| --- | --- | --- |
| compile | Exits immediately | Compiles the contracts |
| test | Runs contract tests | Compiles contracts and runs tests using blockchain defined by env vars |
| runtime | Migrates contracts | Compiles contracts and migrates to the blockchain defined by env vars. Does **not** run tests |

The image makes use of the environment variables described bellow.

| Environment variable | Default value | Usage |
| --- | --- | --- |
| MIGRATE_NETWORK | develop | Set the network where the contracts will be deployed/tested (set this to "env" unless you know what you're doing) |
| DEPLOY_CHAIN_HOST | NaN | Set the hostname of the blockchain network that will be used for deployment (requires network to be "env") |
| DEPLOY_CHAIN_PORT | NaN | Set the port of the blockchain network that will be used for deployment (requires network to be "env") |
| TEST_CHAIN_HOST | NaN | Set the hostname of the blockchain network that will be used for testing (requires network to be "env") |
| TEST_CHAIN_PORT | NaN | Set the port of the blockchain network that will be used for testing (requires network to be "env") |

You can find the contract artifacts in the directory `/usr/src/concordia/packages/concordia-contracts/build/` inside
the image.

**Attention**: make sure the targeted blockchain is up and running before trying to migrate the contracts.

### Application

The Dockerfile provided in the path `./concordia-application` builds the application for production and serves
the resulting build using an nginx server. Dockerfile contains two useful stages, described in the table bellow.

| Stage name | Entrypoint | Usage |
| --- | --- | --- |
| test | Runs tests | Fetches npm packages and runs tests |
| runtime | Serves application | Builds for production and serves it through nginx |


The image makes use of the environment variables described bellow.

| Environment variable | Default value | Usage |
| --- | --- | --- |
| REACT_APP_RENDEZVOUS_HOST | 127.0.0.1 | Set the hostname of the rendezvous server |
| REACT_APP_RENDEZVOUS_PORT | 9090 | Set the port of the rendezvous server |

**Attention**: this image will copy the contract artifacts from the directory `/packages/concordia-contracts/build`.
The image is bound the these artifacts after build. If the contracts change or get re-deployed the image must be
re-built to use the new artifacts.

**Attention**: make sure the contracts have been deployed before **building** this image. Also, make sure the rendezvous
server is up and running.

## Docker Compose

A docker-compose file also is provided. The docker-compose handles the lifecycle of the Ganache and Rendezvous server
containers.

## Putting it all together

You can find some ready to use scripts for common scenarios like dev deploys and testing in the `./docker` directory.
These scripts are documented in the following chapters.

### <a name="piat-mkfile-targets"></a> Makefile targets

Concordia uses blockchain and other distributed technologies. There are a number of ways to set up a running instance of
this application.

This chapter will guide you through simple setups for testing and production that depend on local blockchain (ganache)
instances which do not require real ETH to work or have any other charges.

#### Testing the contracts

Build the ganache image and spin up a blockchain for testing:

```shell
make build-ganache run-ganache-test
```

Build the testing stage of the contracts image:

```shell
make build-contracts-tests
```

Run the tests:

```shell
make run-contracts-tests
```

The results should be printed in the terminal, but are also available in the directory `./reports/contracts`.

#### Testing the application

Build the testing stage of the application image:

```shell
make build-app-tests
```

Run the test:

```shell
make run-app-tests
```

The results should be printed in the terminal, but are also available in the directory `./reports/app`.

#### Production

Just run the target:

```shell
make run
```

And you' re done! Head to [localhost:7777](localhost:7777) and voilà, a working Concordia instance appears! The
blockchain is exposed in the address `localhost:8545`.

**Tip**: the accounts (private keys) generated by Ganache are available in the file `./volumes/ganache_keys/keys.json`.

Note that the `make run` command might take several minutes to execute (depending on your system). What happens under
the hood is that:

- the ganache image is built
- blockchain and rendezvous server containers are started
- migration stage of the contracts image is built
- the contracts are deployed to the blockchain:
- the application image is built and then deployed

### Env Files

Targets in the Makefile make use of env files suffixed by `.docker` located in the directory `./env`. Using this
environment variables, you can change various configuration options of the testing/production deploys.

Targets suffixed with `host-chain` will try to use a blockchain and rendezvous server running in the host machine. They
use the `--net=host` docker option and get the required environment variables from different env files,
`./env/contracts.env` and `./env/concordia.env` (notice these env files don't include the `.docker`). These env files do
not exist by default. The values set will largely depend on how you choose to run services in your system (which ports
you use etc.), so be sure to create them before running any `host-chain` target. Luckily example files are provided.