insight API

insight API is an open-source bitcoin blockchain REST and websocket API. Insight API runs in NodeJS and use LevelDB for storage.

Insight API allows to develop bitcoin related applications such as wallets that require certain information from the blockchain that bitcoind does not provide.

A blockchain explorer front-end have been developed to top of Insight API, it can be downloaded at Github Insight Repository.

IMPORTANT: Upgrading from v0.1 to v0.2

In order to optimize some queries, the key-value layout in Level DB has been changed. If you are running v0.1.x, a total resync needs to be done, running $ util/sync.js -D. This needs to run while insight-api is shut off. See details at: Synchronization.

IMPORTANT: v0.2 Caching schema

In v0.2 a new cache schema has been introduced. Only information from transactions with INSIGHT_SAFE_CONFIRMATIONS+ settings will be cached (by default SAFE_CONFIRMATIONS=6). There are 3 different caches:

nr. of confirmations
transaction spent information
scriptPubKey for unspent transactions

Cache data is only populated on request, i.e., only after accessing the required data for the first time, the information is cached, there is not pre-caching procedure. To ignore cache by default, use INSIGHT_IGNORE_CACHE. Also, address related calls support ?noCache=1 to ignore the cache in a particular API request.

Prerequisites

bitcoind - Download and Install Bitcoin

insight API needs a trusted bitcoind node to run. insight API will connect to the node thru the RPC API, Peer-to-peer protocol and will even read its raw .dat files for syncing.

Configure bitcoind to listen to RPC calls and set txindex to true. The easiest way to do this is by copying ./etc/bitcoind/bitcoin.conf to your bitcoin data directory (usually "~/.bitcoin" on Linux, "%appdata%\Bitcoin\" on Windows, or "~/Library/Application Support/Bitcoin" on Mac OS X).

bitcoind must be running and must have finished downloading the blockchain before running insight API.

Node.js v0.10.x - Download and Install Node.js.
NPM - Node.js package manager, should be automatically installed when you get node.js.

Quick Install

Check the Prerequisites section above before installing.

To install Insight API, clone the main repository:

$ git clone https://github.com/bitpay/insight-api && cd insight-api

Install dependencies:

$ npm install

Run the main application:

$ node insight.js

Then open a browser and go to:

http://localhost:3001

Please note that the app will need to sync its internal database with the blockchain state, which may take some time. You can check sync progress from within the web interface.

Configuration

All configuration is specified in the config folder, particularly the config.js file. There you can specify your application name and database name. Certain configuration values are pulled from environment variables if they are defined:

BITCOIND_HOST         # RPC bitcoind host
BITCOIND_PORT         # RPC bitcoind Port
BITCOIND_P2P_HOST     # P2P bitcoind Host (will default to BITCOIND_HOST, if specified)
BITCOIND_P2P_PORT     # P2P bitcoind Port
BITCOIND_USER         # RPC username
BITCOIND_PASS         # RPC password
BITCOIND_DATADIR      # bitcoind datadir. 'testnet3' will be appended automatically if testnet is used. NEED to finish with '/'. e.g: `/vol/data/`
INSIGHT_NETWORK [= 'livenet' | 'testnet']
INSIGHT_DB            # Path where to store insight's internal DB. (defaults to $HOME/.insight)
INSIGHT_SAFE_CONFIRMATIONS=6  # Nr. of confirmation needed to start caching transaction information   
INSIGHT_IGNORE_CACHE  # True to ignore cache of spents in transaction, with more than INSIGHT_SAFE_CONFIRMATIONS confirmations. This is useful for tracking double spents for old transactions.
ENABLE_MESSAGE_BROKER # if "true" will enable message broker module

Make sure that bitcoind is configured to accept incoming connections using 'rpcallowip'.

In case the network is changed (testnet to livenet or vice versa) levelDB database needs to be deleted. This can be performed running: util/sync.js -D and waiting for insight to synchronize again. Once the database is deleted, the sync.js process can be safely interrupted (CTRL+C) and continued from the synchronization process embedded in main app.

Synchronization

The initial synchronization process scans the blockchain from the paired bitcoind server to update addresses and balances. insight needs one (and only one) trusted bitcoind node to run. This node must have finished downloading the blockchain before running insight.

While insight is synchronizing the website can be accessed (the sync process is embedded in the webserver), but there may be missing data or incorrect balances for addresses. The 'sync' status is shown at the /api/sync endpoint.

The blockchain can be read from bitcoind's raw .dat files or RPC interface. Reading the information from the .dat files is much faster so it's the recommended (and default) alternative. .dat files are scanned in the default location for each platform (for example, ~/.bitcoin on Linux). In case a non-standard location is used, it needs to be defined (see the Configuration section). As of June 2014, using .dat files the sync process takes 9 hrs. for livenet and 30 mins. for testnet.

While synchronizing the blockchain, insight listens for new blocks and transactions relayed by the bitcoind node. Those are also stored on insight's database. In case insight is shutdown for a period of time, restarting it will trigger a partial (historic) synchronization of the blockchain. Depending on the size of that synchronization task, a reverse RPC or forward .dat syncing strategy will be used.

If bitcoind is shutdown, insight needs to be stopped and restarted once bitcoind is restarted.

Syncing old blockchain data manualy

Old blockchain data can be manually synced issuing:

$ util/sync.js

Check util/sync.js --help for options, particulary -D to erase the current DB.

NOTE that there is no need to run this manually since the historic synchronization is embedded on the web application, so by running you will trigger the historic sync automatically.

DB storage requirement

To store the blockchain and address related information, insight uses LevelDB. Two DBs are created: txs and blocks. By default these are stored on ~/.insight/ Please note that previous version's of Insight-API store that on <insight's root>/db

this can be changed on config/config.js. As of June 2014, storing the livenet blockchain takes ~35GB of disk space (2GB for the testnet).

Development

To run insight locally for development with grunt:

$ NODE_ENV=development grunt

To run the tests

$ grunt test

Contributions and suggestions are welcome at insight-api github repository.

API

By default, insight provides a REST API at /api, but this prefix is configurable from the var apiPrefix in the config.js file.

The end-points are:

Block

  /api/block/[:hash]
  /api/block/00000000a967199a2fad0877433c93df785a8d8ce062e5f9b451cd1397bdbf62

Transaction

  /api/tx/[:txid]
  /api/tx/525de308971eabd941b139f46c7198b5af9479325c2395db7f2fb5ae8562556c

Address

  /api/addr/[:addr][?noTxList=1&noCache=1]
  /api/addr/mmvP3mTe53qxHdPqXEvdu8WdC7GfQ2vmx5?noTxList=1

Unspent Outputs

  /api/addr/[:addr]/utxo[?noCache=1]

Sample return:

[
    {
      address: "n2PuaAguxZqLddRbTnAoAuwKYgN2w2hZk7",
      txid: "dbfdc2a0d22a8282c4e7be0452d595695f3a39173bed4f48e590877382b112fc",
      vout: 0,
      ts: 1401276201,
      scriptPubKey: "76a914e50575162795cd77366fb80d728e3216bd52deac88ac",
      amount: 0.001,
      confirmations: 3
    },
    {
      address: "n2PuaAguxZqLddRbTnAoAuwKYgN2w2hZk7",
      txid: "e2b82af55d64f12fd0dd075d0922ee7d6a300f58fe60a23cbb5831b31d1d58b4",
      vout: 0,
      ts: 1401226410,
      scriptPubKey: "76a914e50575162795cd77366fb80d728e3216bd52deac88ac",
      amount: 0.001,
      confirmation: 6    
      confirmationsFromCache: true,
    }
]

Please note that in case confirmations are cached (because the number of confirmations if bigger that INSIGHT_SAFE_CONFIRMATIONS) the return will include the pair confirmationsFromCache:true, and confirmations will equal INSIGHT_SAFE_CONFIRMATIONS. See noCache and INSIGHT_IGNORE_CACHE options for details.

Unspent Outputs for multiple addresses

GET method:

  /api/addrs/[:addrs]/utxo
  /api/addrs/2NF2baYuJAkCKo5onjUKEPdARQkZ6SYyKd5,2NAre8sX2povnjy4aeiHKeEh97Qhn97tB1f/utxo

POST method:

  /api/addrs/utxo

POST params:

addrs: 2NF2baYuJAkCKo5onjUKEPdARQkZ6SYyKd5,2NAre8sX2povnjy4aeiHKeEh97Qhn97tB1f

Transactions by Block

  /api/txs/?block=HASH
  /api/txs/?block=00000000fa6cf7367e50ad14eb0ca4737131f256fc4c5841fd3c3f140140e6b6

Transactions by Address

  /api/txs/?address=ADDR
  /api/txs/?address=mmhmMNfBiZZ37g1tgg2t8DDbNoEdqKVxAL

Historic blockchain data sync status

  /api/sync

Live network p2p data sync status

  /api/peer

Status network

  /api/status?q=xxx

Where "xxx" can be:

getInfo
getDifficulty
getTxOutSetInfo
getBestBlockHash
getLastBlockHash

Web Socket API

The web socket API is served using socket.io at:

  /socket.io/1/

Bitcoin network events published are: 'tx': new transaction received from network. Data will be a app/models/Transaction object. Sample output:

{
  "txid":"00c1b1acb310b87085c7deaaeba478cef5dc9519fab87a4d943ecbb39bd5b053",
  "processed":false
  ...
}

'block': new block received from network. Data will be a app/models/Block object. Sample output:

{
  "hash":"000000004a3d187c430cd6a5e988aca3b19e1f1d1727a50dead6c8ac26899b96",
  "time":1389789343,
  ...
}

'sync': every 1% increment on the sync task, this event will be triggered.

Sample output:

{
  blocksToSync: 164141,
  syncedBlocks: 475,
  upToExisting: true,
  scanningBackward: true,
  isEndGenesis: true,
  end: "000000000933ea01ad0ee984209779baaec3ced90fa3f408719526f8d77f4943",
  isStartGenesis: false,
  start: "000000009f929800556a8f3cfdbe57c187f2f679e351b12f7011bfc276c41b6d"
}

License

(The MIT License)

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.

reorder/insight-api