Fix Context.Input.SetParam not overwriting existing value

- Also added tests for Context.Input.Param handling

context/input.go

@@ -287,6 +287,13 @@ func (input *BeegoInput) Params() map[string]string {
 
 // SetParam will set the param with key and value
 func (input *BeegoInput) SetParam(key, val string) {
+	// check if already exists
+	for i, v := range input.pnames {
+		if v == key && i <= len(input.pvalues) {
+			input.pvalues[i] = val
+			return
+		}
+	}
 	input.pvalues = append(input.pvalues, val)
 	input.pnames = append(input.pnames, key)
 }

context/input_test.go

@@ -18,6 +18,7 @@ import (
 	"fmt"
 	"net/http"
 	"net/http/httptest"
+	"reflect"
 	"testing"
 )
 
@@ -117,3 +118,56 @@ func TestSubDomain(t *testing.T) {
 		t.Fatal("Subdomain parse error, got " + beegoInput.SubDomains())
 	}
 }
+
+func TestParams(t *testing.T) {
+	inp := NewInput()
+
+	inp.SetParam("p1", "val1_ver1")
+	inp.SetParam("p2", "val2_ver1")
+	inp.SetParam("p3", "val3_ver1")
+	if l := inp.ParamsLen(); l != 3 {
+		t.Fatalf("Input.ParamsLen wrong value: %d, expected %d", l, 3)
+	}
+
+	if val := inp.Param("p1"); val != "val1_ver1" {
+		t.Fatalf("Input.Param wrong value: %s, expected %s", val, "val1_ver1")
+	}
+	if val := inp.Param("p3"); val != "val3_ver1" {
+		t.Fatalf("Input.Param wrong value: %s, expected %s", val, "val3_ver1")
+	}
+	vals := inp.Params()
+	expected := map[string]string{
+		"p1": "val1_ver1",
+		"p2": "val2_ver1",
+		"p3": "val3_ver1",
+	}
+	if !reflect.DeepEqual(vals, expected) {
+		t.Fatalf("Input.Params wrong value: %s, expected %s", vals, expected)
+	}
+
+	// overwriting existing params
+	inp.SetParam("p1", "val1_ver2")
+	inp.SetParam("p2", "val2_ver2")
+	expected = map[string]string{
+		"p1": "val1_ver2",
+		"p2": "val2_ver2",
+		"p3": "val3_ver1",
+	}
+	vals = inp.Params()
+	if !reflect.DeepEqual(vals, expected) {
+		t.Fatalf("Input.Params wrong value: %s, expected %s", vals, expected)
+	}
+
+	if l := inp.ParamsLen(); l != 3 {
+		t.Fatalf("Input.ParamsLen wrong value: %d, expected %d", l, 3)
+	}
+
+	if val := inp.Param("p1"); val != "val1_ver2" {
+		t.Fatalf("Input.Param wrong value: %s, expected %s", val, "val1_ver2")
+	}
+
+	if val := inp.Param("p2"); val != "val2_ver2" {
+		t.Fatalf("Input.Param wrong value: %s, expected %s", val, "val1_ver2")
+	}
+
+}