Fixed bug risk and antipattern using deepsource (#904)

## Description

Hi 👋 I ran the [DeepSource](https://deepsource.io/) static analyzer on the forked copy of this repo and found some [interesting code quality issues](https://deepsource.io/gh/ankitdobhal/goreplay/issues/). This PR fixes a few of them.

## Summary of Fixes

- Added .deepsource.toml to fix bug risks
- Empty string test can be improved
- Nested if can be replaced with else-if

## Type of change

- [✔] Antipattern
- [ ] New feature (non-breaking change which adds functionality)

## Checklist:

- [✔] My code follows the style guidelines of this project
- [ ] I have performed a self-review of my own code
- [ ] I have commented my code, particularly in hard-to-understand areas
- [ ] I have made corresponding changes to the documentation

.deepsource.toml

@@ -0,0 +1,28 @@
+version = 1
+
+exclude_patterns = [
+  "vendor/**"
+]
+
+[[analyzers]]
+name = "go"
+enabled = true
+
+  [analyzers.meta]
+  import_paths = ["github.com/ankitdobhal/goreplay"]
+
+[[analyzers]]
+name = "docker"
+enabled = true
+
+[[analyzers]]
+name = "ruby"
+enabled = true
+
+[[analyzers]]
+name = "javascript"
+enabled = true
+
+  [analyzers.meta]
+  environment = ["nodejs"]
+

capture/sock_linux.go

@@ -197,7 +197,7 @@ func (sock *SockRaw) GetSnapLen() int {
 func (sock *SockRaw) SetBPFFilter(expr string) error {
 	sock.mu.Lock()
 	defer sock.mu.Unlock()
-	if len(expr) == 0 {
+	if expr == "" {
 		return unix.SetsockoptInt(sock.fd, unix.SOL_SOCKET, unix.SO_DETACH_FILTER, 0)
 	}
 	filter, err := pcap.CompileBPFFilter(layers.LinkTypeEthernet, sock.snaplen, expr)

gor.go

@@ -31,7 +31,7 @@ func loggingMiddleware(next http.Handler) http.Handler {
 }
 
 func main() {
-	if len(os.Getenv("GOMAXPROCS")) == 0 {
+	if os.Getenv("GOMAXPROCS") == "" {
 		runtime.GOMAXPROCS(runtime.NumCPU() * 2)
 	}
 

input_file.go

@@ -162,11 +162,10 @@ func (i *FileInput) init() (err error) {
 		for _, c := range resp.Contents {
 			matches = append(matches, "s3://"+bucket+"/"+(*c.Key))
 		}
-	} else {
+	} else if matches, err = filepath.Glob(i.path); err != nil{ 
-		if matches, err = filepath.Glob(i.path); err != nil {
 			Debug(0, "[INPUT-FILE] Wrong file pattern", i.path, err)
 			return
-		}
+		
 	}
 
 	if len(matches) == 0 {

input_file_test.go

@@ -29,10 +29,9 @@ func TestInputFileWithGET(t *testing.T) {
 	// The read request should match the original request
 	if err != nil {
 		t.Error(err)
-	} else {
+	} else if !expectedCaptureFile.PayloadsEqual(readPayloads){
-		if !expectedCaptureFile.PayloadsEqual(readPayloads) {
 			t.Error("Request read back from file should match")
-		}
+		
 	}
 }
 
@@ -53,10 +52,9 @@ func TestInputFileWithPayloadLargerThan64Kb(t *testing.T) {
 	// The read request should match the original request
 	if err != nil {
 		t.Error(err)
-	} else {
+	} else if !expectedCaptureFile.PayloadsEqual(readPayloads){ 
-		if !expectedCaptureFile.PayloadsEqual(readPayloads) {
 			t.Error("Request read back from file should match")
-		}
+		
 	}
 
 }
@@ -82,10 +80,9 @@ func TestInputFileWithGETAndPOST(t *testing.T) {
 	// The read requests should match the original request
 	if err != nil {
 		t.Error(err)
-	} else {
+	} else if !expectedCaptureFile.PayloadsEqual(readPayloads){ 
-		if !expectedCaptureFile.PayloadsEqual(readPayloads) {
 			t.Error("Request read back from file should match")
-		}
+		
 	}
 
 }

proto/proto.go

@@ -355,7 +355,7 @@ func HasResponseTitle(payload []byte) bool {
 		return false
 	}
 	// only validate status codes mentioned in rfc2616.
-	if len(http.StatusText(status)) == 0 {
+	if http.StatusText(status) == "" {
 		return false
 	}
 	// handle cases from #875