Simplify template based file generation code.

dash-pipeline/SAI/sai_api_gen.py

@@ -63,6 +63,23 @@ def parse(self, p4rt_value, *args, **kwargs):
 #
 # Parsed SAI objects and parsers
 #
+# The SAI objects are parsed from the P4Runtime JSON file, generated by p4 compiler, which contains the information
+# of all tables and entry information.
+# 
+# The classes below are used to parse the P4Runtime JSON file to get the key information, so we can generate the SAI
+# API headers and implementation files afterwards.
+#
+# At high level, the hiredarchy of the SAI objects is as follows:
+#
+# DASHSAIExtensions: All DASH SAI extensions.
+# - SAIEnum: A single enum type.
+#   - SAIEnumMember: A single enum member within the enum.
+# - SAIAPISet: All information for a single SAI API set, such as routing or CA-PA mapping.
+#   - SAIAPITableData: All information for a single SAI API table used in the API set.
+#     - SAIAPITableKey: Information of a single P4 table key defined in the table.
+#     - SAIAPITableAction: Information of a single P4 table action defined used by the table.
+#       - SAIAPITableActionParam: Information of a single P4 table action parameter used by the action.
+#
 class SAIType:
     sai_type_to_field = {
         'bool': 'booldata',
@@ -300,7 +317,7 @@ def parse_p4rt(self, p4rt_table_key, v4_or_v6_key_ids):
 
         self.id = p4rt_table_key['id']
         self.name = p4rt_table_key[NAME_TAG]
-        print("Parsing table key: " + self.name)
+        #print("Parsing table key: " + self.name)
 
         full_key_name, self.sai_key_name = self.name.split(':')
         key_tuple = full_key_name.split('.')
@@ -365,7 +382,7 @@ def parse_p4rt(self, p4rt_table_action, sai_enums):
                 ]
             }
         '''
-        print("Parsing table action: " + self.name)
+        #print("Parsing table action: " + self.name)
         self.name = self.name.split('.')[-1]
         self.parse_action_params(p4rt_table_action, sai_enums)
 
@@ -384,7 +401,7 @@ def parse_action_params(self, p4rt_table_action, sai_enums):
         # Parse all params.
         for p in p4rt_table_action[PARAMS_TAG]:
             param_name = p[NAME_TAG]
-            param = SAIAPITableActionParam.from_p4rt(p, name = param_name, sai_enums = sai_enums, v4_or_v6_param_ids = v4_or_v6_param_ids)
+            param = SAIAPITableActionParam.from_p4rt(p, sai_enums = sai_enums, v4_or_v6_param_ids = v4_or_v6_param_ids)
             self.params.append(param)
 
         return
@@ -407,9 +424,9 @@ def parse_p4rt(self, p4rt_table_action_param, sai_enums, v4_or_v6_param_ids):
 
             { "id": 1, "name": "dst_vnet_id", "bitwidth": 16 }
         '''
-        print("Parsing table action param: " + self.name)
         self.id = p4rt_table_action_param['id']
         self.name = p4rt_table_action_param[NAME_TAG]
+        #print("Parsing table action param: " + self.name)
 
         if STRUCTURED_ANNOTATIONS_TAG in p4rt_table_action_param:
             self._parse_sai_object_annotation(p4rt_table_action_param)
@@ -457,7 +474,7 @@ def parse_p4rt(self, p4rt_table, program, all_actions, ignore_tables):
         if self.name in ignore_tables:
             return
 
-        print("Found table: " + self.name)
+        print("Parsing table: " + self.name)
 
         self.name, self.api_name = self.name.split('|')
         if '.' in self.name:
@@ -555,7 +572,7 @@ def __merge_action_params_to_table_params(self, action):
                 self.action_params.append(action_param)
 
 
-class DASHAPISet:
+class DASHAPISet(SAIObject):
     '''
     This class holds all parsed SAI API info for a specific API set, such as routing or CA-PA mapping.
     '''
@@ -623,24 +640,36 @@ def __parse_sai_table_action(self, p4rt_actions, sai_enums):
             action_data[action.id] = action
         return action_data
 
+#
+# SAI Generators
+#
+class SAITemplateRender:
+    jinja2_env = None
+
+    @classmethod
+    def new_tm(cls, template_file_path):
+        if cls.jinja2_env == None:
+            cls.env = Environment(loader=FileSystemLoader('.'), trim_blocks=True, lstrip_blocks=True)
+            cls.env.add_extension('jinja2.ext.loopcontrols')
+            cls.env.add_extension('jinja2.ext.do')
+
+        return cls.env.get_template(template_file_path)
 
-def get_uniq_sai_api(sai_api):
-    """ Only keep one table per group(with same table name) """
-    groups = set()
-    sai_api = copy.deepcopy(sai_api)
-    tables = []
-    for table in sai_api.tables:
-        if table.name in groups:
-            continue
-        tables.append(table)
-        groups.add(table.name)
-    sai_api.tables = tables
-    return sai_api
+    def __init__(self, template_file_path):
+        self.template_file_path = template_file_path
+        self.tm = SAITemplateRender.new_tm(template_file_path)
+
+    def render(self, **kwargs):
+        return self.tm.render(**kwargs)
 
+    def render_to_file(self, target_file_path, **kwargs):
+        rendered_str = self.tm.render(**kwargs)
+        write_if_different(target_file_path, rendered_str)
+
 # don't write content to file if file already exists
 # and the content is the same, this will not touch
 # the file and let make utilize this
-def write_if_different(file,content):
+def write_if_different(file, content):
     if os.path.isfile(file) == True:
         o = open(file, "r")
         data = o.read()
@@ -650,41 +679,37 @@ def write_if_different(file,content):
     with open(file, 'w') as o:
         o.write(content)
 
-def write_sai_impl_files(sai_api):
-    env = Environment(loader=FileSystemLoader('.'), trim_blocks=True, lstrip_blocks=True)
-    env.add_extension('jinja2.ext.loopcontrols')
-    env.add_extension('jinja2.ext.do')
-    sai_impl_tm = env.get_template('/templates/saiapi.cpp.j2')
-    if "dash" in sai_api.app_name:
-        header_prefix = "experimental"
-    else:
-        header_prefix = ""
-    sai_impl_str = sai_impl_tm.render(tables = sai_api.tables, app_name = sai_api.app_name, header_prefix = header_prefix)
-    write_if_different('./lib/sai' + sai_api.app_name.replace('_', '') + '.cpp',sai_impl_str)
+class SAIFileUpdater:
+    def __init__(self, file_path):
+        self.file_path = file_path
 
-def write_sai_fixed_api_files(sai_api_full_name_list):
-    env = Environment(loader=FileSystemLoader('.'))
+        with open(file_path, 'r') as f:
+            self.lines = f.readlines()
 
-    for filename in ['saifixedapis.cpp', 'saiimpl.h']:
-        env = Environment(loader=FileSystemLoader('.'), trim_blocks=True, lstrip_blocks=True)
-        sai_impl_tm = env.get_template('/templates/%s.j2' % filename)
-        sai_impl_str = sai_impl_tm.render(tables = sai_api.tables, app_name = sai_api.app_name, api_names = sai_api_full_name_list)
+def get_uniq_sai_api(sai_api):
+    """ Only keep one table per group(with same table name) """
+    groups = set()
+    sai_api = copy.deepcopy(sai_api)
+    tables = []
+    for table in sai_api.tables:
+        if table.name in groups:
+            continue
+        tables.append(table)
+        groups.add(table.name)
+    sai_api.tables = tables
+    return sai_api
 
-        write_if_different('./lib/%s' % filename,sai_impl_str)
+def write_sai_impl_files(sai_api):
+    header_prefix = "experimental" if "dash" in sai_api.app_name else ""
+    SAITemplateRender('templates/saiapi.cpp.j2').render_to_file('./lib/sai' + sai_api.app_name.replace('_', '') + '.cpp', tables = sai_api.tables, app_name = sai_api.app_name, header_prefix = header_prefix)
 
+def write_sai_fixed_api_files(sai_api_full_name_list):
+    for filename in ['saifixedapis.cpp', 'saiimpl.h']:
+        SAITemplateRender('templates/%s.j2' % filename).render_to_file('./lib/%s' % filename, tables = sai_api.tables, app_name = sai_api.app_name, api_names = sai_api_full_name_list)
 
 def write_sai_files(sai_api):
     # The main file
-    with open('templates/saiapi.h.j2', 'r') as sai_header_tm_file:
-        sai_header_tm_str = sai_header_tm_file.read()
-
-    env = Environment(loader=FileSystemLoader('.'), trim_blocks=True, lstrip_blocks=True)
-    env.add_extension('jinja2.ext.loopcontrols')
-    env.add_extension('jinja2.ext.do')
-    sai_header_tm = env.get_template('templates/saiapi.h.j2')
-    sai_header_str = sai_header_tm.render(sai_api = sai_api)
-
-    write_if_different('./SAI/experimental/saiexperimental' + sai_api.app_name.replace('_', '') + '.h',sai_header_str)
+    SAITemplateRender('templates/saiapi.h.j2').render_to_file('./SAI/experimental/saiexperimental' + sai_api.app_name.replace('_', '') + '.h', sai_api = sai_api)
 
     # The SAI Extensions
     with open('./SAI/experimental/saiextensions.h', 'r') as f:
@@ -797,19 +822,14 @@ def write_sai_files(sai_api):
     sai_api_name_list.append(sai_api.app_name.replace('_', ''))
     sai_api_full_name_list.append(sai_api.app_name)
 
-env = Environment(loader=FileSystemLoader('.'), trim_blocks=True, lstrip_blocks=True)
-env.add_extension('jinja2.ext.loopcontrols')
-env.add_extension('jinja2.ext.do')
-
 final_sai_enums = []
 with open('./SAI/experimental/saitypesextensions.h', 'r') as f:
     content = f.read()
     for enum in sai_enums:
         if enum.name not in content:
             final_sai_enums.append(enum)
 
-sai_enums_tm = env.get_template('templates/saienums.j2')
-sai_enums_str = sai_enums_tm.render(sai_enums = final_sai_enums)
+sai_enums_str = SAITemplateRender('templates/saienums.j2').render(sai_enums = final_sai_enums)
 sai_enums_lines = sai_enums_str.split('\n')
 
 # The SAI object struct for entries
@@ -826,7 +846,6 @@ def write_sai_files(sai_api):
 
 write_if_different('./SAI/experimental/saitypesextensions.h',''.join(new_lines))
 
-
 write_sai_fixed_api_files(sai_api_full_name_list)
 
 if args.print_sai_lib: