Overview

The Altchain Bitcoin Finality Indicator (ABFI) service provides an API that returns a number indicating the security of a transaction. This number is called bitcoinFinality and is found in the returned json data.

You can install this service and configure it for your altchain. To get ABFI, you can download this docker image: https://hub.docker.com/r/veriblock/altchain-bfi

Additional setup instructions are available at the docker link. If you are building ABFI from source instead of using the prebuilt docker image, then follow the instructions at the bottom of this page.

Once the ABFI service is running, make HTTP requests to the service through its IP address. For example, use the following URL in your browser to make a request.

http://[ip_to_altchain_bfi]:4568/api/chains/blocks/last-finalized-btc

Altchain BFI API

The following endpoints are accessible at the ABFI API. Modify the URL just shown to make these requests.

Endpoint	Description
/api/chains	Get the last 20 best blocks from the blockchain and any fork blocks at the same height
/api/chains/best	Get the best chain information
/api/chains/blocks/{hash}	Get the SI block for the given hash
/api/chains/blocks/best/{height}	Get the SI best block for the given height
/api/chains/blocks/last-finalized	Get the last finalized block
/api/chains/blocks/last-finalized-btc	Get the last block finalized by btc

Altchain BFI last-finalized-btc endpoint

In order to get responses there should be at least one APM mining at the altchain network also it could take a while (hours), here is a response example for that endpoint:

{
  "id" : "B6D1B863FD54FA855B",
  "height" : 11440,
  "hash" : "000000001E802E0F5AB2CA888290A707B131E3F1DA4A8BB6D1B863FD54FA855B",
  "previousHash" : "0000000AE242C1C892AEA8A3A2682F228289F75F5946530D766CA766BD7768A1",
  "previousKeystone" : "00000001E1A35BD73304BD632DB553613650D73C85153831C58C1B500C773E27",
  "secondKeystone" : "000000027A1B454934C0BFBFF7DD3F40C869882700C6D5817D571A90E9D1AF35",
  "known" : true,
  "popVerified" : true,
  "verifiedIn" : [ {
    "height" : 1576960,
    "hash" : "0000000E68FA6A30244E8532D01CFEBB81BAEB44D6450E28"
  } ],
  "endorsedIn" : [ {
    "height" : 1576960,
    "hash" : "0000000E68FA6A30244E8532D01CFEBB81BAEB44D6450E28"
  }, {
    "height" : 1576966,
    "hash" : "0000000A6040FF891E758D33E1DE54CAA29A4F6AB84E5D30"
  }, {
    "height" : 1576972,
    "hash" : "00000007480E7A9E697EF558B079B1ACDE8882C0EF1B3606"
  }, {
    "height" : 1576980,
    "hash" : "0000000DF194B1596BA7D370D648C7AE16040C0D7EB9CA44"
  }, {
    "height" : 1576982,
    "hash" : "0000001364EBF5245B4A675C10C17F18BE37F635F8670187"
  }, {
    "height" : 1576983,
    "hash" : "0000000D7E0EC709ADFC57AF215FC889A2A1E25E28E04206"
  }, {
    "height" : 1576994,
    "hash" : "000000025C294CA53B43F54FC69C585AAE4C3CD0D416AAA7"
  }, {
    "height" : 1576996,
    "hash" : "000000143032BD8EFB60F1634C9A1F6AFB41E415B6A09E11"
  }, {
    "height" : 1576998,
    "hash" : "000000084D8751DDE79A6ADDEBEB750E95A1CD4E43B5BC6F"
  }, {
    "height" : 1577003,
    "hash" : "000000130E12451DD48F579A4A4F52AD08FAB653885C89DE"
  }, {
    "height" : 1577004,
    "hash" : "0000000D7D6700CF31C70D157CE1F7F362265C6D66AA2CEA"
  }, {
    "height" : 1577005,
    "hash" : "0000000AE903A898C5F2B6A81EBEB4810B1D08590BE22242"
  }, {
    "height" : 1577006,
    "hash" : "000000041D9555371540E9E2C1C0EAC249F63E9FC31C0AD8"
  }, {
    "height" : 1577007,
    "hash" : "00000013377AE0B4A9CB10B176844CAE7ACE051C055DAD70"
  }, {
    "height" : 1577009,
    "hash" : "000000011253477867C52CDE9FE93BA85F2A182643B00FCA"
  } ],
  "spFinality" : 629,
  "bitcoinFinality" : 19,
  "isAttackInProgress" : false
}

Configuring and Building Altchain BFI From Source.

The altchain BFI can be configured through the application.conf file which is inside the bin folder.

Configuration example:

bfi {
  altchainId = vbtc
 
  blockChainNetwork = testnet
 
  nodeCoreRpcHost = "127.0.0.1:10500"
 
  api {
    port = 4568
    notificationsTest = false
  }
 
  forkThreatThreshold = 2
  forkThreatRatioThreshold = 0.8
 
  debugOutput = false
}
 
securityInheriting {
  vbtc: {
    payoutAddress: "0x"
    pluginKey: btc
    id: 3860170
    name: "vBitcoin"
    host: "http://localhost:18332"
    auth: {
      username: "test"
      password: "test"
    }
  }
}

Alternatively you can use the following environment variables to configure the ABFI:

Configuration name	Environment variable	Default	Description
altchainId	ALTCHAIN_ID	undefined	The altchain id, it must be configured
blockChainNetwork	NETWORK	testnet	The altchain network, there are three options: mainnet, testnet and regtest
blockChainRegtestHost	REGTEST_HOST	undefined	The altchain regtest host (the network should be specified as regtest)
nodeCoreRpcHost	NODECORE_HOST	127.0.0.1:10500	The NodeCore ip where the ABFI will connects to
notificationsTest	HTTP_API_NOTIFICATIONS_TEST	false	Enables the /notifications-test endpoint to trigger test notifications
forkThreatThreshold	FORK_THREAT_THRESHOLD	2
forkThreatRatioThreshold	FORK_THREAT_RATIO_THRESHOLD	0.8
debugOutput	DEBUG_OUTPUT	false	Generate debug log files

You can add chains to the securityInheriting block, for example:

Configuration name	Description
payoutAddress	This configuration should be set in order to make the ABFI work but it will be removed, set it to "0x"
pluginKey	The plugin to load
id	The chain id
name	The chain name
host	API url from the coin daemon
auth: username	The username used on the daemon authentication (if any), it can be disabled by commenting the whole auth config block.
auth: password	The password used on the daemon authentication (if any), it can be disabled by commenting the whole auth config block.

Table of Contents

Overview

Altchain BFI API

Altchain BFI last-finalized-btc endpoint

Configuring and Building Altchain BFI From Source.