OPI - Open Protocol Indexer

Open Protocol Indexer, OPI, is the best-in-slot open-source indexing client for meta-protocols on Bitcoin. OPI uses a fork of ord 0.14.0 with minimal changes to maintain compatibility with base layer rules. Also, OPI is built with modularity in mind. The main indexer indexes all text/json inscriptions and modules can extend it with different meta-protocols. All modules in OPI have been built with reorg protection.

Currently OPI has modules for BRC-20 and Bitmap, we'll add new modules over time. Pull Requests are welcomed for other meta-protocols.

Main Meta-Protocol Indexer

Meta-Protocol indexer sits in the core of OPI. It indexes all json/text inscriptions and their first 2 transfers. Transfer limit can be changed via INDEX_TX_LIMIT variable in ord fork. This limit has been added since there are some UTXO's with a lot of inscription content and their movement floods transfers tables. Also, base indexing of most protocols only needs the first two transfers. BRC-20 becomes invalid after 2 hops, bitmap and SNS validity is calculated at inscription time.

BRC-20 Indexer / API

BRC-20 Indexer is the first module of OPI. It follows the official protocol rules hosted here. BRC-20 Indexer saves all historical balance changes and all BRC-20 events.

In addition to indexing all events, it also calculates a block hash and cumulative hash of all events for easier db comparison. Here's the pseudocode for hash calculation:

## Calculation starts at block 767430 which is the first inscription block

EVENT_SEPARATOR = '|'
## max_supply, limit_per_mint, amount decimal count is the same as ticker's decimals (no trailing dot if decimals is 0)
## tickers are lowercase
for event in block_events:
  if event is 'deploy-inscribe':
    block_str += 'deploy-inscribe;<inscr_id>;<deployer_pkscript>;<ticker>;<max_supply>;<decimals>;<limit_per_mint>' + EVENT_SEPARATOR
  if event is 'mint-inscribe':
    block_str += 'mint-inscribe;<inscr_id>;<minter_pkscript>;<ticker>;<amount>' + EVENT_SEPARATOR
  if event is 'transfer-inscribe':
    block_str += 'transfer-inscribe;<inscr_id>;<source_pkscript>;<ticker>;<amount>' + EVENT_SEPARATOR
  if event is 'transfer-transfer':
    ## if sent as fee, sent_pkscript is empty
    block_str += 'transfer-transfer;<inscr_id>;<source_pkscript>;<sent_pkscript>;<ticker>;<amount>' + EVENT_SEPARATOR

if block_str.last is EVENT_SEPARATOR: block_str.remove_last()
block_hash = sha256_hex(block_str)
## for first block last_cumulative_hash is empty
cumulative_hash = sha256_hex(last_cumulative_hash + block_hash)

There is an optional block event hash reporting system pointed at https://api.opi.network/report_block. If you want to exclude your node from this, just change REPORT_TO_INDEXER variable in brc20_index/.env. Also change REPORT_NAME to differentiate your node from others.

BRC-20 API exposes activity on block (block events), balance of a wallet at the start of a given height, current balance of a wallet, block hash and cumulative hash at a given block and hash of all current balances.

Bitmap Indexer / API

Bitmap Indexer is the second module of OPI. It follows the official protocol rules hosted here. Bitmap Indexer saves all bitmap-number inscription-id pairs.

In addition to indexing all pairs, it also calculates a block hash and cumulative hash of all events for easier db comparison. Here's the pseudocode for hash calculation:

## Calculation starts at block 767430 which is the first inscription block

EVENT_SEPARATOR = '|'
for bitmap in new_bitmaps_in_block:
  block_str += 'inscribe;<inscr_id>;<bitmap_number>' + EVENT_SEPARATOR

block_hash = sha256_hex(block_str)
## for first block last_cumulative_hash is empty
cumulative_hash = sha256_hex(last_cumulative_hash + block_hash)

Bitmap API exposes block hash and cumulative hash at a given block, hash of all bitmaps and inscription_id of a given bitmap.

Setup

For detailed installation guides:

• Ubuntu: installation guide

OPI uses PostgreSQL as DB. Before running the indexer, setup a PostgreSQL DB (all modules can write into different databases as well as use a single database).

Build ord:

cd ord; cargo build --release;

Install node modules

cd modules/main_index; npm install;
cd ../brc20_api; npm install;
cd ../bitmap_api; npm install;

Optional: Remove the following from modules/main_index/node_modules/bitcoinjs-lib/src/payments/p2tr.js

if (pubkey && pubkey.length) {
  if (!(0, ecc_lib_1.getEccLib)().isXOnlyPoint(pubkey))
    throw new TypeError('Invalid pubkey for p2tr');
}

Otherwise, it cannot decode some addresses such as 512057cd4cfa03f27f7b18c2fe45fe2c2e0f7b5ccb034af4dec098977c28562be7a2

Install python libraries

pip3 install python-dotenv;
pip3 install psycopg2-binary;

Setup .env files and DBs

Run reset_init.py in each module folder (preferrably start from main_index) to initialise .env file, databases and set other necessary files.

Run

Main Meta-Protocol Indexer

cd modules/main_index; node index.js;

BRC-20 Indexer

cd modules/brc20_index; python3 brc20_index.py;

BRC-20 API

cd modules/brc20_api; node api.js;

Bitmap Indexer

cd modules/bitmap_index; python3 bitmap_index.py;

Bitmap API

cd modules/bitmap_api; node api.js;

Update

• Stop all indexers and apis (preferably starting from main indexer but actually the order shouldn't matter)
• Update the repo (git pull)
• Recompile ord (cd ord; cargo build --release;)
• Re-run all indexers and apis