初步完成一致性hash

LICENSE

@@ -1,6 +1,6 @@
 BSD 3-Clause License
 
-Copyright (c) 2017, 官加文
+Copyright (c) 2017, Guan Jiawen, Li Lundong
 All rights reserved.
 
 Redistribution and use in source and binary forms, with or without

src/github.com/shenaishiren/pentadb/args/args.go

@@ -0,0 +1,55 @@
+// This package implement all argument types that rpc need
+
+/* BSD 3-Clause License
+
+Copyright (c) 2017, Guan Jiawen, Li Lundong
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+* Redistributions of source code must retain the above copyright notice, this
+  list of conditions and the following disclaimer.
+
+* Redistributions in binary form must reproduce the above copyright notice,
+  this list of conditions and the following disclaimer in the documentation
+  and/or other materials provided with the distribution.
+
+* Neither the name of the copyright holder nor the names of its
+  contributors may be used to endorse or promote products derived from
+  this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package args
+
+type InitArgs struct {
+	// a array consisting of each node's ipaddr
+	Nodes []string
+
+	// replicas
+	Replicas int
+}
+
+type KVArgs struct {
+	Key []byte
+
+	Value []byte
+}
+
+type KVArrayArgs struct {
+	KVs []KVArgs
+}
+
+
+

src/github.com/shenaishiren/pentadb/client/client.go

@@ -0,0 +1,123 @@
+// Contains the interface and implementation of PentaDB Client
+
+/* BSD 3-Clause License
+
+Copyright (c) 2017, Guan Jiawen, Li Lundong
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+* Redistributions of source code must retain the above copyright notice, this
+  list of conditions and the following disclaimer.
+
+* Redistributions in binary form must reproduce the above copyright notice,
+  this list of conditions and the following disclaimer in the documentation
+  and/or other materials provided with the distribution.
+
+* Neither the name of the copyright holder nor the names of its
+  contributors may be used to endorse or promote products derived from
+  this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package client
+
+import (
+	"fmt"
+	"errors"
+	"github.com/shenaishiren/pentadb/opt"
+)
+
+const MAXN = 1024
+
+type Client struct {
+	// all nodes in hash ring
+	nodes map[string]*Node
+
+	// hash ring
+	hashRing *HashRing
+
+	// the channel is used for checking what node is lost
+	unreachableChan chan string
+}
+
+func NewClient(nodeIpaddrs []string, weights map[string]int, replicas int) (*Client, error) {
+	// check nodes' count
+	nodesCount := len(nodeIpaddrs)
+	if nodesCount < opt.DefaultReplicas + 1 {
+		return nil, errors.New(
+			fmt.Sprintf("server number must be >= %d", opt.DefaultReplicas + 1),
+		)
+	}
+	// initialize hash ring
+	hashRing := NewHashRing()
+	nodes, _ := hashRing.init(nodeIpaddrs, weights)
+	nodeDict := make(map[string]*Node)
+	for _, node := range nodes {
+		nodeDict[node.Name] = node
+		go node.Proxy.init(nodeIpaddrs, &opt.NodeProxyOptions{Replicas: replicas})
+	}
+	// initialize client
+	client := &Client{
+		nodes: nodeDict,
+		hashRing: hashRing,
+		unreachableChan: make(chan string, MAXN),
+	}
+	// event loop about checking nodes
+	go func() {
+		for {
+			select {
+				case nodeName := <- client.unreachableChan:
+					client.removeNode(nodeName)
+			}
+		}
+	}()
+
+	return client, nil
+}
+
+func (c *Client) addNode(nodeIpaddr string, weight int) {
+	node := c.hashRing.addNode(nodeIpaddr, weight)
+	c.nodes[nodeIpaddr] = node
+	node.Proxy.addNode(nodeIpaddr)
+}
+
+func (c *Client) removeNode(nodeName string) {
+	node := c.nodes[nodeName]
+	node.Proxy.removeNode(node.Ipaddr)
+	delete(c.nodes, nodeName)
+}
+
+func (c *Client) getNode(nodeName string) *Node {
+	return c.nodes[nodeName]
+}
+
+func (c *Client) put(key []byte, value []byte) error {
+	// choose a node
+	hashKey := KemataHash(string(key), 0)
+	node, _ := c.hashRing.findProperNode(hashKey)
+	return node.rNode.Proxy.put(key, value)
+}
+
+func (c *Client) get(key []byte) ([]byte, error) {
+	hashKey := KemataHash(string(key), 0)
+	node, _ := c.hashRing.findProperNode(hashKey)
+	return node.rNode.Proxy.get(key)
+}
+
+func (c *Client) delete(key []byte) error {
+	hashKey := KemataHash(string(key), 0)
+	node, _ := c.hashRing.findProperNode(hashKey)
+	return node.rNode.Proxy.delete(key)
+}