Added unit tests for StringSubstitutionFilter

tests/filters/configs/stringsubstitutionfilter.cfg

@@ -0,0 +1,18 @@
+# Config file for unit testing StringSubstitutionFilter.
+
+[etl]
+chains = input_string_file|string_sub_filter|packet_buffer|output_std
+
+[input_string_file]
+class = inputs.fileinput.StringFileInput
+file_path = tests/data/stringfileinput_formatargs.txt
+
+[string_sub_filter]
+class = filters.stringfilter.StringSubstitutionFilter
+format_args = greeting:Hello name:NLExtract
+
+[packet_buffer]
+class = filters.packetbuffer.PacketBuffer
+
+[output_std]
+class = outputs.standardoutput.StandardOutput

tests/filters/test_string_substitution_filter.py

@@ -0,0 +1,38 @@
+import os
+
+from stetl.etl import ETL
+from stetl.filters.packetbuffer import PacketBuffer
+from stetl.filters.stringfilter import StringSubstitutionFilter
+from tests.stetl_test_case import StetlTestCase
+
+class StringSubstitutionFilterTest(StetlTestCase):
+    """Unit tests for StringSubstitutionFilter"""
+
+    def setUp(self):
+        super(StringSubstitutionFilterTest, self).setUp()
+
+        # Initialize Stetl
+        curr_dir = os.path.dirname(os.path.realpath(__file__))
+        cfg_dict = {'config_file': os.path.join(curr_dir, 'configs/stringsubstitutionfilter.cfg')}
+        self.etl = ETL(cfg_dict)
+
+    def test_class(self):
+        chain = StetlTestCase.get_chain(self.etl)
+        section = StetlTestCase.get_section(chain, 1)
+        class_name = self.etl.configdict.get(section, 'class')
+
+        self.assertEqual('filters.stringfilter.StringSubstitutionFilter', class_name)
+
+    def test_instance(self):
+        chain = StetlTestCase.get_chain(self.etl)
+
+        self.assertTrue(isinstance(chain.get_by_index(1), StringSubstitutionFilter))
+
+    def test_execute(self):
+        chain = StetlTestCase.get_chain(self.etl)
+        chain.run()
+
+        buffer_filter = chain.get_by_class(PacketBuffer)
+        packet_list = buffer_filter.packet_list
+
+        self.assertEqual(packet_list[0].data, 'Hello NLExtract!')