feat: initial daemon implementation

.dockerignore

@@ -0,0 +1 @@
+dist/

.editorconfig

@@ -0,0 +1,9 @@
+root = true
+
+[*]
+charset = utf-8
+end_of_line = lf
+indent_size = 2
+indent_style = space
+insert_final_newline = true
+trim_trailing_whitespace = true

.github/workflows/main.yml

@@ -0,0 +1,32 @@
+name: CI
+on: [push]
+jobs:
+  build:
+    name: Build, lint, and test on Node ${{ matrix.node }} and ${{ matrix.os }}
+
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        node: ['10.x', '12.x', '14.x']
+        os: [ubuntu-latest, windows-latest, macOS-latest]
+
+    steps:
+      - name: Checkout repo
+        uses: actions/checkout@v2
+
+      - name: Use Node ${{ matrix.node }}
+        uses: actions/setup-node@v1
+        with:
+          node-version: ${{ matrix.node }}
+
+      - name: Install deps and build (with cache)
+        uses: bahmutov/npm-install@v1
+
+      - name: Lint
+        run: yarn lint
+
+      - name: Test
+        run: yarn test --ci --coverage --maxWorkers=2
+
+      - name: Build
+        run: yarn build

.gitignore

@@ -0,0 +1,5 @@
+*.log
+.DS_Store
+node_modules
+dist
+.env

Dockerfile

@@ -0,0 +1,22 @@
+# Copyright 2020 Hathor Labs
+# This software is provided ‘as-is’, without any express or implied
+# warranty. In no event will the authors be held liable for any damages
+# arising from the use of this software.
+# This software cannot be redistributed unless explicitly agreed in writing with the authors.
+
+FROM node:14 AS builder
+
+COPY package.json /app/
+
+RUN cd /app && npm install --production
+
+COPY . /app/
+
+RUN cd /app && npm run build
+
+FROM node:14-alpine3.13 AS builder
+
+COPY --from=builder /app/dist/ /app/
+COPY --from=builder /app/node_modules /app/node_modules
+
+CMD node /app/index.js

LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2020 Hathor Labs
+
+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.

README.md

@@ -0,0 +1,108 @@
+# Hathor Wallet Service -- Sync Daemon
+
+## Running
+
+### Local environment
+
+#### System dependencies
+
+You need nodejs installed on your enviroment, we are using the latest Active LTS version (v14.16.1) on the dev environment. You can read more about installing nodejs on https://nodejs.org/en/download/package-manager/
+
+#### Clone the project and install dependencies
+
+`git clone https://github.com/HathorNetwork/hathor-wallet-service-sync_daemon.git && npm install`
+
+#### Add env variables or an .env file to the repository:
+
+Example:
+
+```
+STAGE=local
+NETWORK=testnet
+MAX_ADDRESS_GAP=20
+SERVICE_NAME=hathor-wallet-service
+DEFAULT_SERVER=http://fullnode_url/v1a/
+```
+
+`STAGE` - Wallet-Service's deployment stage, e.g. `local`, `production`, `staging`
+`NETWORK` - The current hathor network we want to connect to
+`MAX_ADDRESS_GAP` - The full-node configured GAP between addresses
+`SERVICE_NAME` - The Wallet-Service's service name as it was registered on AWS
+`DEFAULT_SERVER` - The full-node API url
+
+If the wallet-service is not running locally, you also need to specify the AWS-SDK env variables:
+
+```
+AWS_REGION="us-east-1"
+AWS_DEFAULT_REGION="us-east-1"
+AWS_ACCESS_KEY_ID="..."
+AWS_SECRET_ACCESS_KEY="..."
+```
+
+#### Run:
+
+`npm start`
+
+
+### Deploy
+
+The recommended way to deploy this service is to use docker.
+
+#### Building the image:
+
+`docker build -t hathor/sync-daemon .`
+
+#### Running:
+
+```
+docker run -d -e STAGE="production" \
+           -e NODE_ENV="production" \
+           -e AWS_REGION="us-east-1" \
+           -e AWS_DEFAULT_REGION="us-east-1" \
+           -e AWS_ACCESS_KEY_ID="..." \
+           -e AWS_SECRET_ACCESS_KEY="..." \
+           -e NETWORK="testnet" \
+           -e MAX_ADDRESS_GAP=20 \
+           -e NETWORK="testnet" \
+           -e SERVICE_NAME="hathor-wallet-service" \
+           -e DEFAULT_SERVER="http://fullnode:8082/v1a/" \
+           -ti localhost/hathor/sync-daemon
+```
+
+In this example, we are passing the env variables to the container and running as a daemon (`-d`). We are also expecting a fullnode to be running on fullnode:8082.
+
+## State Machine
+
+The state machine diagram can be visualized at https://xstate.js.org/viz/?gist=7299c0ed0ce189bc121a06dce1e11638
+
+## States:
+
+### Idle
+
+The machine starts at the idle state, it will stay there until a `NEW_BLOCK` action is received.
+
+Every time the state of the machine is transitioned to `idle`, the machine will check if `hasMoreBlocks` is set on the state context. If it is, the machine will transition to `syncing`.
+
+#### Actions:
+  `NEW_BLOCK`: When a `NEW_BLOCK` action is received, the machine will transition to the `syncing` state.
+
+### Syncing
+
+Everytime the state of the machine is transitioned to `syncing`, the machine will invoke the `syncHandler` service that will start syncing new blocks.
+
+#### Actions:
+  `NEW_BLOCK`: When a `NEW_BLOCK` action is received, the machine will assign `true` to the `hasMoreBlocks` context on the state, so the next time we transition to `IDLE`, the machine will know that there are more blocks to be downloaded.
+  `DONE`: When a `DONE` action is received, the machine will transition to `idle` to await for new blocks
+  `ERROR`: When a `ERROR` action is received, the machine will transition to the `failure` state
+  `REORG`: When a `REORG` action is received, the machine will transition to the `reorg` state
+  `STOP`: When a `STOP` action is received, the machine will transition to the `idle` state
+
+### Failure
+
+This is a `final` state, meaning that the machine will ignore all actions and wait for a manual restart.
+
+This state can trigger actions to try to automatically solve issues or notify us about it.
+
+### Reorg
+
+This is temporarily a `final` state, this will be changed on a new PR with the reorg code.