Adding the basic features

.github/workflows/build_go.yml

@@ -23,3 +23,7 @@ jobs:
 
     - name: Test
       run: go test -v ./...
+
+    - name: Run golangci-lint
+      uses: golangci/[email protected]
+

.github/workflows/coverage_go.yml

@@ -0,0 +1,58 @@
+on:
+  pull_request:
+    branches:
+      - main
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    name: Update coverage badge
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+        with:
+          persist-credentials: false # otherwise, the token used is the GITHUB_TOKEN, instead of your personal access token.
+          fetch-depth: 0 # otherwise, there would be errors pushing refs to the destination repository.
+
+      - name: Setup go
+        uses: actions/setup-go@v2
+        with:
+          go-version: '1.14.4'
+
+      - uses: actions/cache@v2
+        with:
+          path: ~/go/pkg/mod
+          key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
+          restore-keys: |
+            ${{ runner.os }}-go-
+
+      - name: Run Test
+        run: |
+          go test -v ./... -covermode=count -coverprofile=coverage.out
+          go tool cover -func=coverage.out -o=coverage.out
+
+      - name: Go Coverage Badge  # Pass the `coverage.out` output to this action
+        uses: tj-actions/[email protected]
+        with:
+          filename: coverage.out
+
+      - name: Verify Changed files
+        uses: tj-actions/[email protected]
+        id: verify-changed-files
+        with:
+          files: README.md
+
+      - name: Commit changes
+        if: steps.verify-changed-files.outputs.files_changed == 'true'
+        run: |
+          git config --local user.email "[email protected]"
+          git config --local user.name "GitHub Action"
+          git add README.md
+          git commit -m "chore: Updated coverage badge."
+
+      - name: Push changes
+        if: steps.verify-changed-files.outputs.files_changed == 'true'
+        uses: ad-m/github-push-action@master
+        with:
+          github_token: ${{ github.token }}
+          branch: ${{ github.head_ref }}

.gitignore

@@ -1,3 +1,12 @@
+# Logs
+logs.txt
+
+# Temporary files
+tmp/*
+
+# VSCode
+.vscode/*
+
 # Binaries for programs and plugins
 *.exe
 *.exe~

blockchain/block.go

@@ -0,0 +1,91 @@
+package blockchain
+
+import (
+	"bytes"
+	"crypto/sha256"
+	"encoding/gob"
+	"encoding/json"
+	"strconv"
+	"strings"
+
+	logging "github.com/MVRetailManager/MVInventoryChain/logging"
+)
+
+type Block struct {
+	Index         int
+	UnixTimeStamp int64
+	Hash          []byte
+	PreviousHash  []byte
+	Nonce         int
+	Difficulty    int
+	Transaction   []*Transaction
+}
+
+func NewBlock(index int, unixTimeStamp int64, previousHash []byte, transaction []*Transaction) *Block {
+	b := &Block{
+		Index:         index,
+		UnixTimeStamp: unixTimeStamp,
+		Hash:          make([]byte, 32),
+		PreviousHash:  previousHash,
+		Nonce:         0,
+		Difficulty:    1,
+		Transaction:   transaction,
+	}
+
+	logging.BlocksLogger.Printf("Block Initialised: %v\n", b)
+
+	b.Mine()
+
+	return b
+}
+
+func (b *Block) Mine() {
+	for !b.validateHash(b.calculateHash()) {
+		b.Nonce++
+		b.Hash = b.calculateHash()
+	}
+
+	logging.BlocksLogger.Printf("Block Mined:\n Nonce: %v\nHash: %v\n", b.Nonce, b.Hash)
+}
+
+func (b *Block) calculateHash() []byte {
+	hash := sha256.Sum256([]byte(strconv.Itoa(b.Index) + strconv.FormatInt(b.UnixTimeStamp, 10) + string(b.PreviousHash) + strconv.Itoa(b.Nonce) + strconv.Itoa(b.Difficulty) + transactionToString(b.Transaction)))
+	return hash[:]
+}
+
+func (b *Block) validateHash(hash []byte) bool {
+	prefix := strings.Repeat("0", b.Difficulty)
+	return strings.HasPrefix(string(hash), prefix)
+}
+
+func first(n []byte, _ error) []byte {
+	return n
+}
+
+func transactionToString(transaction []*Transaction) string {
+	return string(first(json.Marshal(transaction)))
+}
+
+func (bc *Block) Serialize() []byte {
+	var res bytes.Buffer
+
+	encoder := gob.NewEncoder(&res)
+
+	err := encoder.Encode(bc)
+
+	HandleError(err)
+
+	return res.Bytes()
+}
+
+func Deserialize(data []byte) *Block {
+	var block Block
+
+	decoder := gob.NewDecoder(bytes.NewReader(data))
+
+	err := decoder.Decode(&block)
+
+	HandleError(err)
+
+	return &block
+}