configuration parsing for client and namenode, bug fixes

client/client.go

@@ -5,6 +5,9 @@ import (
 	"bufio"
 	"bytes"
 	"encoding/json"
+	"encoding/xml"
+	"strconv"
+
 	"errors"
 	"fmt"
 	"io"
@@ -15,10 +18,11 @@ import (
 	"sync"
 )
 
-const SERVERADDR = "localhost:8080"
-const SIZEOFBLOCK = 4096
-
-var id string                        // client id
+// Config Options
+var serverhost string                // serverhost
+var serverport string                // serverport
+var SIZEOFBLOCK int                  //size of block in bytes
+var id string                        // the namenode id
 var state = HB                       // internal statemachine
 var sendChannel chan Packet          // for outbound Packets
 var receiveChannel chan Packet       // for in bound Packets
@@ -41,6 +45,17 @@ const (
 	ERROR         = iota // notification of a failed request
 )
 
+// The XML parsing structures for configuration options
+type ConfigOptionList struct {
+	XMLName       xml.Name       `xml:"ConfigOptionList"`
+	ConfigOptions []ConfigOption `xml:"ConfigOption"`
+}
+
+type ConfigOption struct {
+	Key   string `xml:"key,attr"`
+	Value string `xml:",chardata"`
+}
+
 // A file is composed of one or more Blocks
 type Block struct {
 	Header BlockHeader // metadata
@@ -51,7 +66,7 @@ type Block struct {
 type BlockHeader struct {
 	DatanodeID string // ID of datanode which holds the block
 	Filename   string //the remote name of the block including the path "/test/0"
-	Size       int64  // size of Block in bytes
+	Size       int    // size of Block in bytes
 	BlockNum   int    // the 0 indexed position of Block within file
 	NumBlocks  int    // total number of Blocks in file
 }
@@ -124,7 +139,7 @@ func BlockHeadersFromFile(localname, remotename string) []BlockHeader {
 	}()
 
 	// Create Blocks
-	numblocks := int((info.Size() / SIZEOFBLOCK) + 1)
+	numblocks := int(info.Size()/int64(SIZEOFBLOCK) + 1)
 	headers = make([]BlockHeader, numblocks, numblocks)
 	blocknum := 0
 
@@ -133,9 +148,9 @@ func BlockHeadersFromFile(localname, remotename string) []BlockHeader {
 			remotename = "/" + remotename
 		}
 
-		n := int64(SIZEOFBLOCK)
+		n := SIZEOFBLOCK
 		if blocknum == (numblocks - 1) {
-			n = int64(info.Size()) % SIZEOFBLOCK
+			n = int(info.Size() % int64(SIZEOFBLOCK))
 
 		}
 
@@ -182,7 +197,7 @@ func DistributeBlocksFromFile(localname, remotename string) error {
 	r := bufio.NewReader(fi)
 
 	// Create Blocks
-	total := int((info.Size() / SIZEOFBLOCK) + 1)
+	total := int((info.Size() / int64(SIZEOFBLOCK)) + 1)
 
 	num := 0
 
@@ -209,7 +224,7 @@ func DistributeBlocksFromFile(localname, remotename string) error {
 			remotename = "/" + remotename
 		}
 
-		h := BlockHeader{"", remotename, int64(n), num, total}
+		h := BlockHeader{"", remotename, n, num, total}
 
 		data := make([]byte, 0, n)
 		data = w.Bytes()[0:n]
@@ -220,6 +235,7 @@ func DistributeBlocksFromFile(localname, remotename string) error {
 			return err
 		}
 
+		fmt.Printf(".")
 		// generate new Block
 		num += 1
 
@@ -228,6 +244,7 @@ func DistributeBlocksFromFile(localname, remotename string) error {
 		return err
 	}
 
+	fmt.Printf(" Done! \n")
 	return nil
 }
 
@@ -250,14 +267,17 @@ func DistributeBlock(b Block) error {
 
 func DistributeBlocks(blocks []Block) error {
 
+	fmt.Println("Distributing file blocks")
 	for _, b := range blocks {
 
 		err := DistributeBlock(b)
-
 		if err != nil {
-			return errors.New("Could not distribute blocks to namenode")
+			return errors.New("Distrubution Error: " + err.Error())
 		}
+		fmt.Printf(".")
 	}
+	fmt.Printf(" Done! \n")
+
 	return nil
 }
 
@@ -278,7 +298,7 @@ func RetrieveFile(localname, remotename string) {
 	p.SRC = id
 	p.CMD = GETHEADERS
 	p.Headers = make([]BlockHeader, 1, 1)
-	p.Headers[0] = BlockHeader{"", remotename, int64(0), 0, 0}
+	p.Headers[0] = BlockHeader{"", remotename, 0, 0, 0}
 	encoder.Encode(*p)
 
 	// get header list
@@ -372,7 +392,6 @@ func ReceiveInput() {
 			}
 
 			// generate blocks from new File for distribution
-			fmt.Println("Distributing file blocks")
 			err = DistributeBlocksFromFile(localname, remotename)
 
 			if err != nil {
@@ -393,11 +412,55 @@ func ReceiveInput() {
 
 }
 
+// Parse Config sets up the node with the provided XML file
+func ParseConfigXML(configpath string) error {
+	xmlFile, err := os.Open(configpath)
+	if err != nil {
+		return err
+	}
+	defer xmlFile.Close()
+
+	var list ConfigOptionList
+	err = xml.NewDecoder(xmlFile).Decode(&list)
+	if err != nil {
+		return err
+	}
+
+	for _, o := range list.ConfigOptions {
+
+		switch o.Key {
+		// single client for now
+		//	case "id":
+		//		id = o.Value
+		case "serverhost":
+			serverhost = o.Value
+		case "serverport":
+			serverport = o.Value
+		case "sizeofblock":
+			n, err := strconv.Atoi(o.Value)
+			if err != nil {
+				return err
+			}
+
+			if n < 4096 {
+				return errors.New("Buffer size must be greater than or equal to 4096 bytes")
+			}
+			SIZEOFBLOCK = n
+		default:
+			return errors.New("Bad ConfigOption received Key : " + o.Key + " Value : " + o.Value)
+		}
+	}
+
+	return nil
+}
+
 // Initializes the client and begins communication
-func Init() {
+func Run(configpath string) {
+
+	ParseConfigXML(configpath)
 
 	id = "C"
-	conn, err := net.Dial("tcp", SERVERADDR)
+	conn, err := net.Dial("tcp", serverhost+":"+serverport)
 	CheckError(err)
 
 	encoder = json.NewEncoder(conn)

client/configparser_test.go

@@ -0,0 +1,30 @@
+package client
+
+import (
+	"testing"
+)
+
+func TestValidXML(t *testing.T) {
+
+	err := ParseConfigXML("exampleclient.xml")
+	if err != nil {
+		t.Errorf(err.Error())
+	}
+	// Single client for now
+	//	if id != "C" {
+	//		t.Errorf("Config did not set id correctly")
+	//	}
+
+	if serverhost != "localhost" {
+		t.Errorf("Config did not set host correctly")
+	}
+
+	if serverport != "8080" {
+		t.Errorf("Config did not set port correctly")
+	}
+
+	if SIZEOFBLOCK != 4096 {
+		t.Errorf("Config did not set SIZEOFBLOCK correctly")
+	}
+
+}

client/exampleclient.xml

@@ -0,0 +1,5 @@
+<ConfigOptionList>
+	<ConfigOption key="serverhost">localhost</ConfigOption>
+	<ConfigOption key="serverport">8080</ConfigOption>
+	<ConfigOption key="sizeofblock">4096</ConfigOption>
+</ConfigOptionList>

datanode/configparser_test.go

@@ -0,0 +1,34 @@
+package datanode
+
+import (
+	"testing"
+)
+
+func TestValidXML(t *testing.T) {
+
+	err := ParseConfigXML("exampledatanode.xml")
+	if err != nil {
+		t.Errorf(err.Error())
+	}
+
+	if id != "DN1" {
+		t.Errorf("Config did not set id correctly")
+	}
+
+	if root != "/DN1" {
+		t.Errorf("Config did not set id correctly")
+	}
+
+	if serverhost != "localhost" {
+		t.Errorf("Config did not set host correctly")
+	}
+
+	if serverport != "8080" {
+		t.Errorf("Config did not set port correctly")
+	}
+
+	if SIZEOFBLOCK != 4096 {
+		t.Errorf("Config did not set SIZEOFBLOCK correctly")
+	}
+
+}