Add: proper error handling for files

src/go/pt-galera-log-explainer/internal.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"bufio"
+	"os"
 	"os/exec"
 	"runtime"
 	"strings"
@@ -25,6 +26,10 @@ func init() {
 	}
 }
 
+var (
+	errDirectoriesUnsupported = errors.New("directories are not supported")
+)
+
 // timelineFromPaths takes every path, search them using a list of regexes
 // and organize them in a timeline that will be ready to aggregate or read
 func timelineFromPaths(paths []string, regexes types.RegexMap) (types.Timeline, error) {
@@ -34,6 +39,14 @@ func timelineFromPaths(paths []string, regexes types.RegexMap) (types.Timeline,
 	compiledRegex := prepareGrepArgument(regexes)
 
 	for _, path := range paths {
+		osinfo, err := os.Stat(path)
+		if err != nil {
+			return nil, err
+		}
+		if osinfo.IsDir() {
+			return nil, errDirectoriesUnsupported
+		}
+
 		stdout := make(chan string)
 
 		go func() {
@@ -193,7 +206,6 @@ func iterateOnGrepResults(path string, regexes types.RegexMap, grepStdout <-chan
 			}
 			ctx, displayer = regex.Handle(ctx, line)
 			li := types.NewLogInfo(date, displayer, line, regex, key, ctx, filetype)
-
 			lt = lt.Add(li)
 		}
 

src/go/pt-galera-log-explainer/internal_test.go

@@ -0,0 +1,31 @@
+package main
+
+import (
+	"errors"
+	"os"
+	"testing"
+)
+
+func TestTimelineFromPaths(t *testing.T) {
+	tests := []struct {
+		path        string
+		expectedErr error
+	}{
+		{
+			path:        "tests/logs/",
+			expectedErr: errDirectoriesUnsupported,
+		},
+		{
+			path:        "tests/logs/non_existing",
+			expectedErr: os.ErrNotExist,
+		},
+	}
+
+	for _, test := range tests {
+		_, err := timelineFromPaths([]string{test.path}, nil)
+		if !errors.Is(err, test.expectedErr) {
+			t.Fatalf("with path %s, expected error %v, got %v", test.path, test.expectedErr, err)
+		}
+	}
+
+}