add different than conditions

README.md

@@ -66,6 +66,11 @@ Count total requests to urls matching a pattern:
 
 	$ ngtop -w url=/blog/%
 
+Count total requests to urls excluding a value or pattern:
+
+	$ ngtop -w url!=/feed.xml
+	$ ngtop -w url!=/feed%
+
 Count total requests to one of mutliple urls (one OR another):
 
 	$ ngtop -w url=/blog/code-is-run-more-than-read -w url=/blog/a-note-on-essential-complexity

db.go

@@ -172,9 +172,19 @@ func (spec *RequestCountSpec) buildQuery() (string, []any) {
 		for i, value := range values {
 			whereExpression += column
 			if strings.ContainsRune(value, '%') {
-				whereExpression += " LIKE ?"
+				if strings.HasPrefix(value, "!") {
+					value = strings.TrimPrefix(value, "!")
+					whereExpression += " NOT LIKE ?"
+				} else {
+					whereExpression += " LIKE ?"
+				}
 			} else {
-				whereExpression += " = ?"
+				if strings.HasPrefix(value, "!") {
+					value = strings.TrimPrefix(value, "!")
+					whereExpression += " <> ?"
+				} else {
+					whereExpression += " = ?"
+				}
 			}
 			queryArgs = append(queryArgs, value)
 			if i < len(values)-1 {

main.go

@@ -114,10 +114,14 @@ func resolveWhereConditions(clauses []string) (map[string][]string, error) {
 	conditions := make(map[string][]string)
 
 	for _, clause := range clauses {
+		// for non equal conditions, leave a trailing '!' in the value
+		clause = strings.Replace(clause, "!=", "=!", 1)
+
 		keyvalue := strings.Split(clause, "=")
 		if len(keyvalue) != 2 {
 			return nil, fmt.Errorf("invalid where expression %s", clause)
 		}
+
 		if column, found := FIELD_NAMES[keyvalue[0]]; !found {
 			return nil, fmt.Errorf("unknown field name %s", keyvalue[0])
 		} else {

main_test.go

@@ -76,12 +76,13 @@ func TestWhereConditionParsing(t *testing.T) {
 	var cond map[string][]string
 	var err error
 
-	cond, err = resolveWhereConditions([]string{"url=/blog", "useragent=Safari", "ua=Firefox", "referer=olano%"})
+	cond, err = resolveWhereConditions([]string{"url=/blog", "useragent=Safari", "ua=Firefox", "referer=olano%", "os!=Windows"})
 	assertEqual(t, err, nil)
 	assertEqual(t, cond, map[string][]string{
 		"path":       {"/blog"},
 		"user_agent": {"Safari", "Firefox"},
 		"referer":    {"olano%"},
+		"os":         {"!Windows"},
 	})
 
 	// include error on unknown field
@@ -224,6 +225,20 @@ func TestWherePattern(t *testing.T) {
 	assertEqual(t, len(rows), 3)
 }
 
+func TestWhereNegation(t *testing.T) {
+	_, rows := runCommand(t, SAMPLE_LOGS, []string{"url", "-w", "status!=200", "-l", "10"})
+	assertEqual(t, len(rows), 5)
+
+	_, rows = runCommand(t, SAMPLE_LOGS, []string{"url", "-w", "status!=301", "-l", "10"})
+	assertEqual(t, len(rows), 3)
+
+	_, rows = runCommand(t, SAMPLE_LOGS, []string{"url", "-w", "status!=2%", "-l", "10"})
+	assertEqual(t, len(rows), 5)
+
+	_, rows = runCommand(t, SAMPLE_LOGS, []string{"url", "-w", "status!=3%", "-l", "10"})
+	assertEqual(t, len(rows), 3)
+}
+
 func TestMultipleLogFiles(t *testing.T) {
 	// TODO
 	// more than one file in a dir, honoring the glob pattern