This Gist gives you the rough idea about how to

get_entries_test.go

func TestGetEntries(t *testing.T) {
	req, err := http.NewRequest("GET", "/entries", nil)
	if err != nil {
		t.Fatal(err)
	}
	rr := httptest.NewRecorder()
	handler := http.HandlerFunc(GetEntries)
	handler.ServeHTTP(rr, req)
	if status := rr.Code; status != http.StatusOK {
		t.Errorf("handler returned wrong status code: got %v want %v",
			status, http.StatusOK)
	}

	// Check the response body is what we expect.
	expected := `[{"id":1,"first_name":"Krish","last_name":"Bhanushali","email_address":"[email protected]","phone_number":"0987654321"},{"id":2,"first_name":"xyz","last_name":"pqr","email_address":"[email protected]","phone_number":"1234567890"},{"id":6,"first_name":"FirstNameSample","last_name":"LastNameSample","email_address":"[email protected]","phone_number":"1111111111"}]`
	if rr.Body.String() != expected {
		t.Errorf("handler returned unexpected body: got %v want %v",
			rr.Body.String(), expected)
	}
}