Here be dragons!

This version of blockexplorer.com is a raw work in progress that probably needs special handling to get into working condition. Don't expect it to just work, just yet. Handle with care. It may eat your pets.

In its current state you'll probably have to know what you're doing to get it to do anything. If you can't figure it out on your own please come back later. Eventually I plan on making it very easy to get a copy of the site working but we're not there yet.

The code in this repository was originally written in a hurry by Michael Marquardt AKA Theymos. Since Michael didn't have time to continue working on blockexplorer.com he decided to pass the torch to Liraz. That's me. Unfortunately I don't have a lot of free time either since I spend most of it developing TurnKey Linux. So rather than doing everything myself the plan was to focus on bootstrapping blockexplorer into an open source project and get more people on board. I'd like blockexplorer to become a neutral open source resource by the Bitcoin community, for the Bitcoin community.

Rewrite in progress: what I've done so far

Unfortunately, the original code was in a deeply troubled state. If you want to see what I mean, checkout the Initial commit. I very much doubt anyone would have had fun working on it in its original condition so I volunteered myself for janitorial duty and have started a rewrite. It's dirty work, but somebody has to do it!

What I've done so far:

• separated model/view/content
• eliminated most code repetition
• improved readability across the board
• added a templating system (smarty)
• created improved abstraction layers for caching, database and bitcoind RPC API
• moved various hardwired configurations that were interwoven in various spots in the code into a single configuration file
• eliminated use of gotos and globals
• fixed the most glaring performance issues

So far the code for the web application has been reduced from 6000 to 2500 lines of code.

I nearly finished the rewrite but then I ran out of time around May 2013 and had to get back to working on TurnKey (we had a release coming out). I was planning on getting back to this in a few weeks, put everything into working order and then release the code in working condition. Unfortunately that didn't happen and continuing details have convinced me it would be a better to just publish the incomplete development code rather than continue to sit on it.

This way perhaps it can at least serve as a useful educational resource for people interested in Bitcoin. OK, so maybe I'm also secretly hoping someone will be interested in this enough to pick up the gauntlet and make some progress until I get back to this.

Setup instructions

Prerequisite: depends on an older custom patched bitcoind

https://github.com/lirazsiri/blockexplorer-bitcoind

Setting up the database

explore.schema contains the current database schema.

We grant write permissions to the blockupdate user (used to run the blockupdate script) and read permissions to the www-data user - under which we run the main blockexplorer web application.

Setting up the web application

1. Copy this repository to /var/www/blockexplorer.com.
2. You can use any web server so long as you properly configure it. I use lighttpd for the development version. You can find the lighttpd configuration I use in contrib/lighttpd-conf. This goes in /etc/lighttpd.

Configuration and initial setup of the major components

1. htdocs/ contains the refactored blockexplorer.com web application which provides a web representation of the blockchain.

   It needs read-only access to the database table where you will store the blockchain. It also communicates with bitcoind over RPC API for some queries.

   You can configure the the blockexplorer web application by editing htdocs/includes/config.inc.

1. bin/blockupdate*.php scripts connect to bitcoind over RPC API and copies blockchain data into the database. These scripts are intended to run from a cron job:

   BBE=/var/www/blockexplorer.com/ */1 * * * *      blockupdate
   $BBE/bin/blockupdate.php >> $BBE/logs/blockupdate.log */1 * * * *
   blockupdate $BBE/bin/blockupdate-testnet.php >>
   $BBE/logs/blockupdate-testnet.log
   

   These scripts haven't been rewritten yet so it still depends on pre-rewrite code that has all the configurations such as database table name hardwired. In other words, unlike the web application in htdocs/ the bin/ scripts don't take configurations from htdocs/includes/config.inc.

   You'll need to identify the hardwired configurations and change them if you want blockupdate to work for you.

   If you haven't run blockupdate before, the first run will copy the entire blockchain into the database. This can take a while. Subsequent runs will only add new blocks however.

   These scripts need write access to the database table containing the blockchain. The current code needs 10X the amount of diskspace for the database version of the blockchain compared with bitcoin-qt.

   In other words, if bitcoin-qt's copy of the blockchain is 1GB, blockexplorer database table will require 10GB of diskspace.

   BTW, there's no inherent the copy of the blockchain in the database has to be 10X larger than the copy in bitcoind. This is just due to inefficiencies.

   For this reason however, it's recommended to run development versions of blockexplorer.com against testnet rather than mainnet. The testnet blockchain is much smaller.