git ssb

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var Flume = require('flumedb')
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var OffsetLog = require('flumelog-offset')
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var mkdirp = require('mkdirp')
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var ViewHashTable = require('flumeview-hashtable')
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var codec = require('flumecodec/json')
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var path = require('path')
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var hash = require('ssb-keys/util').hash
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function getId(msg) {
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  return '%'+hash(JSON.stringify(msg, null, 2))
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}
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module.exports = function (config) {
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  //we'll store out of order messages in their own log
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  //so that we don't interfere with the views on in in-order messages
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  //it does mean we'll download them again later if we follow
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  //this feed, but it makes everything simpler overall
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  //and the point of messages is to be small
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  //and the point of ooo messages is that there
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  //is not really that many.
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  var log = OffsetLog(
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    path.join(config.path, 'ooo', 'log.offset'),
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    {blockSize:1024*16, codec:codec}
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  )
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  var store = Flume(log)
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    .use('keys', ViewHashTable(2, function (key) {
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      var b = new Buffer(key.substring(1,7), 'base64').readUInt32BE(0)
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      return b
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    }))
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  store.add = function (msg, cb) {
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    var data = {
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      key: getId(msg),
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      value: msg,
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      timestamp: Date.now()
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    }
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    store.append(data, function (err) {
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      if(err) cb(err)
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      else cb(null, data)
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    })
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  }
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  return store
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}
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