hub/README.md

## Scribe

Scribe is a python library for building services that use the processed data from the [LBRY blockchain](https://github.com/lbryio/lbrycrd) in an ongoing manner. Scribe contains a set of three core executable services that are used together:
 * `scribe` ([scribe.blockchain.service](https://github.com/lbryio/scribe/tree/master/scribe/blockchain/service.py)) - maintains a [rocksdb](https://github.com/lbryio/lbry-rocksdb) database containing the LBRY blockchain.
 * `scribe-hub` ([scribe.hub.service](https://github.com/lbryio/scribe/tree/master/scribe/hub/service.py)) - an electrum server for thin-wallet clients (such as [lbry-sdk](https://github.com/lbryio/lbry-sdk)), provides an api for clients to use thin simple-payment-verification (spv) wallets and to resolve and search claims published to the LBRY blockchain.
 * `scribe-elastic-sync` ([scribe.elasticsearch.service](https://github.com/lbryio/scribe/tree/master/scribe/elasticsearch/service.py)) - a utility to maintain an elasticsearch database of metadata for claims in the LBRY blockchain

Features and overview of scribe as a python library:
 * Uses Python 3.7-3.9 (3.10 probably works but hasn't yet been tested)
 * An interface developers may implement in order to build their own applications able to receive up-to-date blockchain data in an ongoing manner ([scribe.service.BlockchainReaderService](https://github.com/lbryio/scribe/tree/master/scribe/service.py))
 * Protobuf schema for encoding and decoding metadata stored on the blockchain ([scribe.schema](https://github.com/lbryio/scribe/tree/master/scribe/schema))
 * [Rocksdb 6.25.3](https://github.com/lbryio/lbry-rocksdb/) based database containing the blockchain data ([scribe.db](https://github.com/lbryio/scribe/tree/master/scribe/db))
 * [A community driven performant trending algorithm](https://raw.githubusercontent.com/lbryio/scribe/master/scribe/elasticsearch/trending%20algorithm.pdf) for searching claims ([code](https://github.com/lbryio/scribe/blob/master/scribe/elasticsearch/fast_ar_trending.py))

## Installation

Scribe may be run from source, a binary, or a docker image.
Our [releases page](https://github.com/lbryio/scribe/releases) contains pre-built binaries of the latest release, pre-releases, and past releases for macOS and Debian-based Linux.
Prebuilt [docker images](https://hub.docker.com/r/lbry/scribe/latest-release) are also available.

### Prebuilt docker image

`docker pull lbry/scribe:latest-release`

### Build your own docker image

```
git clone https://github.com/lbryio/scribe.git
cd scribe
docker build -f ./docker/Dockerfile.scribe -t lbry/scribe:development .
```

### Install from source

Scribe has been tested with python 3.7-3.9. Higher versions probably work but have not yet been tested.

1. clone the scribe scribe
```
git clone https://github.com/lbryio/scribe.git
cd scribe
```
2. make a virtual env
```
python3.9 -m venv scribe-venv
```
3. from the virtual env, install scribe
```
source scribe-venv/bin/activate
pip install -e .
```

That completes the installation, now you should have the commands `scribe`, `scribe-elastic-sync` and `scribe-hub`

These can also optionally be run with `python -m scribe.blockchain`, `python -m scribe.elasticsearch`, and `python -m scribe.hub`

## Usage

### Requirements

Scribe needs elasticsearch and either the [lbrycrd](https://github.com/lbryio/lbrycrd) or [lbcd](https://github.com/lbryio/lbcd) blockchain daemon to be running.

With options for high performance, if you have 64gb of memory and 12 cores, everything can be run on the same machine. However, the recommended way is with elasticsearch on one instance with 8gb of memory and at least 4 cores dedicated to it and the blockchain daemon on another with 16gb of memory and at least 4 cores. Then the scribe hub services can be run their own instance with between 16 and 32gb of memory (depending on settings) and 8 cores. 

As of block 1147423 (4/21/22) the size of the scribe rocksdb database is 120GB and the size of the elasticsearch volume is 63GB.

### docker-compose

The recommended way to run a scribe hub is with docker.

#### Cluster environment

[Example docker-compose.yml](https://github.com/lbryio/scribe/blob/master/docker/elastic-compose.yml) for the elasticsearch instance

[Example docker-compose.yml](https://github.com/lbryio/scribe/blob/master/docker/hub-compose.yml)  for the hub instance


### From source

### Options

#### Common options across `scribe`, `scribe-hub`, and `scribe-elastic-sync`:
  - `--db_dir` (required) Path of the directory containing lbry-rocksdb, set from the environment with `DB_DIRECTORY`
  - `--daemon_url` (required for `scribe` and `scribe-hub`) URL for rpc from lbrycrd or lbcd<rpcuser>:<rpcpassword>@<lbrycrd rpc ip><lbrycrd rpc port>.
  - `--reorg_limit` Max reorg depth, defaults to 200, set from the environment with `REORG_LIMIT`.
  - `--chain` With blockchain to use - either `mainnet`, `testnet`, or `regtest` - set from the environment with `NET`
  - `--max_query_workers` Size of the thread pool, set from the environment with `MAX_QUERY_WORKERS`
  - `--cache_all_tx_hashes` If this flag is set, all tx hashes will be stored in memory. For `scribe`, this speeds up the rate it can apply blocks as well as process mempool. For `scribe-hub`, this will speed up syncing address histories. This setting will use 10+g of memory. It can be set from the environment with `CACHE_ALL_TX_HASHES=Yes`
  - `--cache_all_claim_txos` If this flag is set, all claim txos will be indexed in memory. Set from the environment with `CACHE_ALL_CLAIM_TXOS=Yes`
  - `--prometheus_port` If provided this port will be used to provide prometheus metrics, set from the environment with `PROMETHEUS_PORT`

#### Options for `scribe`
  - `--db_max_open_files` This setting translates into the max_open_files option given to rocksdb. A higher number will use more memory. Defaults to 64.

#### Options for `scribe-elastic-sync`
  - `--reindex` If this flag is set drop and rebuild the elasticsearch index.

#### Options for `scribe-hub`
  - `--host` Interface for server to listen on, use 0.0.0.0 to listen on the external interface. Can be set from the environment with `HOST`
  - `--tcp_port` Electrum TCP port to listen on for hub server. Can be set from the environment with `TCP_PORT`
  - `--udp_port` UDP port to listen on for hub server. Can be set from the environment with `UDP_PORT`
  - `--elastic_host` Hostname or ip address of the elasticsearch instance to connect to. Can be set from the environment with `ELASTIC_HOST`
  - `--elastic_port` Elasticsearch port to connect to. Can be set from the environment with `ELASTIC_PORT`
  - `--elastic_notifier_host` Elastic sync notifier host to connect to, defaults to localhost. Can be set from the environment with `ELASTIC_NOTIFIER_HOST`
  - `--elastic_notifier_port` Elastic sync notifier port to connect using. Can be set from the environment with `ELASTIC_NOTIFIER_PORT`
  - `--query_timeout_ms` Timeout for claim searches in elasticsearch in milliseconds. Can be set from the environment with `QUERY_TIMEOUT_MS`
  - `--blocking_channel_ids` Space separated list of channel claim ids used for blocking. Claims that are reposted by these channels can't be resolved or returned in search results. Can be set from the environment with `BLOCKING_CHANNEL_IDS`.
  - `--filtering_channel_ids` Space separated list of channel claim ids used for blocking. Claims that are reposted by these channels aren't returned in search results. Can be set from the environment with `FILTERING_CHANNEL_IDS`

## Contributing

Contributions to this project are welcome, encouraged, and compensated. For more details, please check [this](https://lbry.tech/contribute) link.

## License

This project is MIT licensed. For the full license, see [LICENSE](LICENSE).

## Security

We take security seriously. Please contact security@lbry.com regarding any security issues. [Our PGP key is here](https://lbry.com/faq/pgp-key) if you need it.

## Contact

The primary contact for this project is [@jackrobison](mailto:jackrobison@lbry.com).