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README.md

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+# dht-rpc
+
+Make RPC calls over a Kademlia based DHT.
+
+```
+npm install dht-rpc
+```
+
+## Usage
+
+Here is an example implementing a simple key value store
+
+First spin up a bootstrap node. You can make multiple if you want for redundancy.
+
+``` js
+var dht = require('dht-rpc')
+
+// Set ephemeral: true so other peers do not add us to the peer list, simply bootstrap
+var bootstrap = dht({ephemeral: true})
+
+bootstrap.listen(10001)
+```
+
+Now lets make some dht nodes that can store values in our key value store.
+
+``` js
+var dht = require('dht-rpc')
+var crypto = require('crypto')
+
+// Let's create 100 dht nodes for our example.
+for (var i = 0; i < 100; i++) createNode()
+
+function createNode () {
+  var node = dht({
+    bootstrap: ['localhost:10001']
+  })
+
+  var values = {}
+
+  // When we are the closest node and someone is sending us a "store" command
+  node.on('closest:store', function (query, cb) {
+    if (!query.value) return cb()
+
+    // Use the hash of the value as the key
+    var key = sha256(query.value).toString('hex')
+    values[key] = query.value
+    console.log('Storing', key, '-->', query.value.toString())
+    cb()
+  })
+
+  // When someone is querying for a "lookup" command
+  node.on('query:lookup', function (query, cb) {
+    var value = values[query.target.toString('hex')]
+    cb(null, value)
+  })
+}
+
+function sha256 (val) {
+  return crypto.createHash('sha256').update(val).digest('hex')
+}
+```
+
+To insert a value into this dht make another script that does this following
+
+``` js
+// Set ephemeral: true as we are not part of the network.
+var node = dht({ephemeral: true})
+
+node.closest({command: 'store', target: sha256(val), value: val}, function (err, res) {
+  if (err) throw err
+  console.log('Inserted', sha256(val).toString('hex'))
+})
+```
+
+Then after inserting run this script to query for a value
+
+``` js
+node.query({command: 'lookup', target: new Buffer(hexFromAbove, 'hex')})
+  .on('data', function (data) {
+    if (data.value && sha256(data.value).toString('hex') === hexFromAbove) {
+      // We found the value! Destroy the query stream as there is no need to continue.
+      console.log(val, '-->', data.value.toString())
+      this.destroy()
+    }
+  })
+  .on('end', function () {
+    console.log('(query finished)')
+  })
+```
+
+## License
+
+MIT