README.md

<br /><br />

<div align="center">
  <h1 align="center">@substrate/api-sidecar</h1>
  <h4 align="center"> REST service that makes it easy to interact with blockchain nodes built using Substrate's
    <a href="https://substrate.dev/docs/en/knowledgebase/runtime/frame">FRAME</a>
    framework.</h4>
  <p align="center">
    <a href="https://www.npmjs.com/package/@substrate/api-sidecar">
      <img alt="npm" src="https://img.shields.io/npm/v/@substrate/api-sidecar" />
    </a>
    <a href="https://github.com/paritytech/substrate-api-sidecar/actions">
      <img alt="Github Actions" src="https://github.com/paritytech/substrate-api-sidecar/workflows/pr/badge.svg" />
    </a>
    <a href="https://github.com/paritytech/substrate-api-sidecar/blob/master/LICENSE">
      <img alt="GPL-3.0-or-later" src="https://img.shields.io/npm/l/@substrate/api-sidecar" />
    </a>
  </p>
</div>

<br /><br />

## Note

v1.0.0 was released on 2020-10-23. This major release introduced several renamed endpoints as breaking changes. It is important that users complete the transition to the new endpoints ASAP so they are ready for any subsequent emergency updates. Please visit the [MIGRATION_GUIDE](./guides/MIGRATION_GUIDE.md) to
learn more.

## Prerequisites

### <= v15.0.0
This service requires Node versions 14 or higher.

Compatibility:
| Node Version  | Stablility  |
|---------------|:-----------:|
|     v14.x.x   |   Stable    |
|     v16.x.x   |   Stable    |
|     v17.x.x   |   Stable    |
|     v18.x.x   |   Stable    |
|     v19.x.x   |   stable    |

### >= v16.0.0
This service requires Node versions 18.14 or higher.

Compatibility:
| Node Version  | Stablility  |
|---------------|:-----------:|
|     v18.14.x  |   Stable    |
|     v20.x.x   |   Stable    |
|     v21.x.x   |   Pending   |

NOTE: Node LTS (`long term support`) versions start with an even number, and odd number versions are subject to a 6 month testing period with active support before they are unsupported. It is recommended to use sidecar with a stable actively maintained version of node.js.

## Table of contents

- [NPM package installation and usage](#npm-package-installation-and-usage)
- [Source code installation and usage](#source-code-installation-and-usage)
- [Configuration](#configuration)
- [Debugging fee and staking payout calculations](#debugging-staking-payout-calculations)
- [Available endpoints](https://paritytech.github.io/substrate-api-sidecar/dist/)
- [Chain integration guide](./guides/CHAIN_INTEGRATION.md)
- [Docker](#docker)
- [Notes for maintainers](#notes-for-maintainers)
- [Hardware requirements](#hardware-requirements)

## NPM package installation and usage

### Global installation

Install the service globally:

```bash
npm install -g @substrate/api-sidecar
# OR
yarn global add @substrate/api-sidecar
```

Run the service from any directory on your machine:

```bash
substrate-api-sidecar
```

To check your version you may append the `--version` flag to `substrate-api-sidecar`.

### Local installation

Install the service locally:

```bash
npm install @substrate/api-sidecar
# OR
yarn add @substrate/api-sidecar
```

Run the service from within the local directory:

```bash
node_modules/.bin/substrate-api-sidecar
```

### Finishing up

[Jump to the configuration section](#configuration) for more details on connecting to a node.

[Click here for full endpoint docs.](https://paritytech.github.io/substrate-api-sidecar/dist/)

In the full endpoints doc, you will also find the following `trace` related endpoints :
- `/experimental/blocks/{blockId}/traces/operations?actions=false`
- `/experimental/blocks/head/traces/operations?actions=false`
- `/experimental/blocks/{blockId}/traces`
- `/experimental/blocks/head/traces`

To have access to these endpoints you need to :
1. Run your node with the flag `—unsafe-rpc-external`
2. Check in sidecar if `BlocksTrace` controller is active for the chain you are running.

Currently `BlocksTrace` controller is active in [Polkadot](https://github.com/paritytech/substrate-api-sidecar/blob/ff0cef5eaeeef74f9a931a0355d83fc5ebdea645/src/chains-config/polkadotControllers.ts#L17) and [Kusama](https://github.com/paritytech/substrate-api-sidecar/blob/ff0cef5eaeeef74f9a931a0355d83fc5ebdea645/src/chains-config/kusamaControllers.ts#L17).

## Source code installation and usage

### Quick install

Simply run `yarn`.

### Rust development installation

If you are looking to hack on the `calc` Rust crate make sure your machine has an [up-to-date version of `rustup`](https://www.rust-lang.org/tools/install)
installed to manage Rust dependencies.

Install `wasm-pack` if your machine does not already have it:

```bash
cargo install wasm-pack
```

Use yarn to do the remaining setup:

```bash
yarn
```

### Running

```bash
# For live reload in development
yarn dev

# To build and run
yarn build
yarn start
```

[Jump to the configuration section](#configuration) for more details on connecting to a node.

## Configuration

To use a specific env profile (here for instance a profile called 'env.sample'):

```bash
NODE_ENV=sample yarn start
```

For more information on our configuration manager visit its readme [here](https://gitlab.com/chevdor/confmgr/-/raw/master/README.adoc). See `Specs.ts` to view the env configuration spec.

### Express server

- `SAS_EXPRESS_BIND_HOST`: address on which the server will be listening, defaults to `127.0.0.1`.
- `SAS_EXPRESS_PORT`: port on which the server will be listening, defaults to `8080`.
- `SAS_EXPRESS_KEEP_ALIVE_TIMEOUT`: Set the `keepAliveTimeout` in express.

### Substrate node

- `SAS_SUBSTRATE_URL`: URL to which the RPC proxy will attempt to connect to, defaults to
    `ws://127.0.0.1:9944`. Accepts both a websocket, and http URL.

#### Custom substrate types

Some chains require custom type definitions in order for Sidecar to know how to decode the data
retrieved from the node. Sidecar affords environment variables which allow the user to specify an absolute path to a JSON file that contains type definitions in the corresponding formats. Consult polkadot-js/api for more info on
the type formats (see `RegisteredTypes`). There is a helper CLI tool called [generate-type-bundle](https://github.com/paritytech/generate-type-bundle) that can generate a `typesBundle.json` file for you using chain information from [`@polkadot/apps-config`](https://github.com/polkadot-js/apps/tree/master/packages/apps-config). The generated json file from this tool will work directly with the `SAS_SUBSTRATE_TYPES_BUNDLE` ENV variable. 

- `SAS_SUBSTRATE_TYPES_BUNDLE`: a bundle of types with versioning info, type aliases, derives, and
    rpc definitions. Format: `OverrideBundleType` (see [`typesBundle`](https://github.com/polkadot-js/api/blob/21039dec1fcad36061a96bf5526248c5fab38780/packages/types/src/types/registry.ts#L72)).
- `SAS_SUBSTRATE_TYPES_CHAIN`: type definitions keyed by `chainName`. Format: `Record<string, RegistryTypes>` (see [`typesChain`](https://github.com/polkadot-js/api/blob/21039dec1fcad36061a96bf5526248c5fab38780/packages/types/src/types/registry.ts#L76)).
- `SAS_SUBSTRATE_TYPES_SPEC`: type definitions keyed by `specName`. Format: `Record<string, RegistryTypes>` (see [`typesSpec`](https://github.com/polkadot-js/api/blob/21039dec1fcad36061a96bf5526248c5fab38780/packages/types/src/types/registry.ts#L80)).
- `SAS_SUBSTRATE_TYPES`: type definitions and overrides, not keyed. Format: `RegistryTypes` (see [`types`](https://github.com/polkadot-js/api/blob/21039dec1fcad36061a96bf5526248c5fab38780/packages/types/src/types/registry.ts#L64)).

You can read more about [defining types for polkadot-js here.](https://polkadot.js.org/api/start/types.extend.html)

##### Connecting a modified node template

Polkadot-js can recognize the standard node template and inject the correct types, but if you have
modified the name of your chain in the node template you will need to add the types manually in a
JSON `types` file like so:

```json
// my-chains-types.json
{
  "Address": "AccountId",
  "LookupSource": "AccountId"
}
```

and then set the enviroment variable to point to your definitions:

```bash
export SAS_SUBSTRATE_TYPES=/path/to/my-chains-types.json
```

### Logging

- `SAS_LOG_LEVEL`: The lowest priority log level to surface, defaults to `info`. Tip: set to `http`
    to see all HTTP requests.
- `SAS_LOG_JSON`:Whether or not to have logs formatted as JSON, defaults to `false`.
    Useful when using `stdout` to programmatically process Sidecar log data.
- `SAS_LOG_FILTER_RPC`: Whether or not to filter polkadot-js API-WS RPC logging, defaults to `false`.
- `SAS_LOG_STRIP_ANSI`: Whether or not to strip ANSI characters from logs, defaults
    to `false`. Useful when logging RPC calls with JSON written to transports.
- `SAS_LOG_WRITE`: Whether or not to write logs to a log file. Default is set to `false`. Accepts a boolean value. The log files will be written as `logs.log`. **NOTE**: It will only log what is available depending on what `SAS_LOG_LEVEL` is set to.
- `SAS_LOG_WRITE_PATH`: Specifies the path to write the log files. Default will be where the package is installed.
- `SAS_LOG_WRITE_MAX_FILE_SIZE`: Specifies in bytes what the max file size for the written log files should be. Default is `5242880` (5MB). **NOTE** Once the the max amount of files have reached their max size, the logger will start to rewrite over the first log file.
- `SAS_LOG_WRITE_MAX_FILES`: Specifies how many files can be written. Default is 5.

#### Log levels

Log levels in order of decreasing importance are: `error`, `warn`, `info`, `http`, `verbose`, `debug`, `silly`.

| http status code range | log level |
|------------------------|-----------|
| `code` < 400           | `http`    |
| 400 <= `code` < 500    | `warn`    |
| 500 < `code`           | `error`   |

#### RPC logging

If looking to track raw RPC requests/responses, one can use `yarn start:log-rpc` to turn on polkadot-js's
logging. It is recommended to also set `SAS_LOG_STRIP_ANSI=true` to increase the readability of the logging stream.

**N.B.** If running `yarn start:log-rpc`, the NODE_ENV will be set to `test`. In order still run your `.env`
file you can `symlink` it with `.env.test`. For example you could run
`ln -s .env.myEnv .env.test && yarn start:log-rpc` to use `.env.myEnv` to set ENV variables. (see linux
commands `ln` and `unlink` for more info.)

### Prometheus server
Prometheus metrics can be enabled by running sidecar with the following flag :

```bash
yarn start --prometheus
```

You can also define a custom port by running :

```bash
yarn start --prometheus --prometheus-port=<YOUR_CUSTOM_PORT>
```

The metrics endpoint can then be accessed :
- on the default port : `http://127.0.0.1:9100/metrics` or
- on your custom port if you defined one : `http://127.0.0.1:<YOUR_CUSTOM_PORT>/metrics`

That way you will have access to the default prometheus metrics and one extra custom metric called `sas_http_errors` (of type counter). This counter is increased by 1 every time an http error has occured in sidecar.


## Debugging fee and staking payout calculations

It is possible to get more information about the fee and staking payout calculation process logged to
the console. Because these calculations happens in the statically compiled web assembly part,
a re-compile with the proper environment variable set is necessary:

```bash
CALC_DEBUG=1 sh calc/build.sh
```

## Available endpoints

[Click here for full endpoint docs.](https://paritytech.github.io/substrate-api-sidecar/dist/)

## Chain integration guide

[Click here for chain integration guide.](./guides/CHAIN_INTEGRATION.md)

## Docker

With each release, the maintainers publish a docker image to dockerhub at [parity/substrate-api-sidecar](https://hub.docker.com/r/parity/substrate-api-sidecar/tags?page=1&ordering=last_updated)

### Pull the latest release

```bash
docker pull docker.io/parity/substrate-api-sidecar:latest
```

The specific image tag matches the release version.

### Or build from source

```bash
yarn build:docker
```

### Run

```bash
# For default use run:
docker run --rm -it --read-only -p 8080:8080 substrate-api-sidecar

# Or if you want to use environment variables set in `.env.docker`, run:
docker run --rm -it --read-only --env-file .env.docker -p 8080:8080 substrate-api-sidecar
```

**NOTE**: While you could omit the `--read-only` flag, it is **strongly recommended for containers used in production**.

then you can test with:

```bash
curl -s http://0.0.0.0:8080/blocks/head | jq
```

**N.B.** The docker flow presented here is just a sample to help get started. Modifications may be necessary for secure usage.

## Contribute

Need help or want to contribute ideas or code? Head over to our [CONTRIBUTING](./guides/CONTRIBUTING.md) doc for more information.

## Notes for maintainers

### Commits

All the commits in this repo follow the [Conventional Commits spec](https://www.conventionalcommits.org/en/v1.0.0/#summary). When merging a PR, make sure 1) to use squash merge and 2) that the title of the PR follows the Conventional Commits spec.

### Updating polkadot-js dependencies

1. Every Monday the polkadot-js ecosystem will usually come out with a new release. It's important that we keep up,
and read the release notes for any breaking changes or high priority updates. In order to update all the dependencies and resolutions run `yarn up "@polkadot/*"`.

    - @polkadot/api [release notes](https://github.com/polkadot-js/api/releases)
    - @polkadot/util-crypto [release notes](https://github.com/polkadot-js/common/releases)
    - @substrate/calc [npm release page](https://www.npmjs.com/package/@substrate/calc)

1. Ensure everything is up to date and working by running the following:
   ```
   yarn
   yarn dedupe
   yarn build
   yarn lint
   yarn test
   yarn test:historical-e2e-tests
   yarn test:latest-e2e-tests
   ```

1. Commit the dependency updates with a name like `fix(deps): update pjs api` (title depending on what got updated, see commit history for other examples of this), and wait to get it merged.

1. Follow [RELEASE.md](./RELEASE.md) next if you're working through a full sidecar release. This will involve creating a separate PR where the changelog and versions are bumped.

## Hardware requirements

### Disk Space
Sidecar is a stateless program and thus should not use any disk space.

### Memory
The requirements follow the default of node.js processes which is an upper bound in HEAP memory of a little less than 2GB thus 4GB of memory should be sufficient.

### Running sidecar and a node
Please note that if you run sidecar next to a substrate node in a single machine then your system specifications should improve significantly.
- Our official specifications related to validator nodes can be found in the polkadot wiki [page](https://wiki.polkadot.network/docs/maintain-guides-how-to-validate-polkadot#standard-hardware).
- Regarding archive nodes :
  - again as mentioned in the polkadot wiki [page](https://wiki.polkadot.network/docs/maintain-sync#types-of-nodes), the space needed from an archive node depends on which block we are currently on (of the specific chain we are referring to).
  - there are no other hardware requirements for an archive node since it is not time critical (archive nodes do not participate in the consensus).

### Benchmarks
During the benchmarks we performed, we concluded that sidecar would use a max of 1.1GB of RSS memory.

The benchmarks were:
- using 4 threads over 12 open http connections and
- were overloading the cache with every runtime possible on polkadot.

Hardware specs in which the benchmarks were performed:
```
Machine type:
n2-standard-4 (4 vCPUs, 16 GB memory)

CPU Platform:
Intel Cascade Lake

Hard-Disk:
500GB
```