Starts work on adding recipe upgrade feature

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- First-pass attempt at integrating `conda-recipe-manager` into Grayskull for
  the purposes of generating recipes in the V1 format.

environment.yaml

@@ -29,3 +29,4 @@ dependencies:
   - libcblas
   - beautifulsoup4
   - semver >=3.0.0,<4.0.0
+  # - conda-recipe-manager >=0.2.0

grayskull/main.py

@@ -92,6 +92,15 @@ def init_parser():
         help="If sections are specified, grayskull will populate just the sections "
         "informed.",
     )
+    cran_parser.add_argument(
+        "--use-v1-format",
+        "-u",
+        default=False,
+        action="store_true",
+        dest="use_v1_format",
+        help="Returns a recipe file in the V1 format, used by rattler-build."
+        " NOTE: This is experimental.",
+    )
     # create parser for pypi
     pypi_parser = subparsers.add_parser("pypi", help="Options to generate PyPI recipes")
     pypi_parser.add_argument(
@@ -244,6 +253,15 @@ def init_parser():
         dest="licence_exclude_folders",
         help="Exclude folders when searching for licence.",
     )
+    pypi_parser.add_argument(
+        "--use-v1-format",
+        "-u",
+        default=False,
+        action="store_true",
+        dest="use_v1_format",
+        help="Returns a recipe file in the V1 format, used by rattler-build."
+        " NOTE: This is experimental.",
+    )
 
     return parser
 
@@ -319,7 +337,7 @@ def generate_recipes_from_list(list_pkgs, args):
         if args.sections_populate is None or "extra" in args.sections_populate:
             add_extra_section(recipe, args.maintainers)
 
-        generate_recipe(recipe, config, args.output)
+        generate_recipe(recipe, config, args.output, args.use_v1_format)
         print_msg(
             f"\n{Fore.GREEN}#### Recipe generated on "
             f"{os.path.realpath(args.output)} for {pkg_name} ####\n\n"
@@ -365,7 +383,7 @@ def generate_r_recipes_from_list(list_pkgs, args):
         if args.sections_populate is None or "extra" in args.sections_populate:
             add_extra_section(recipe, args.maintainers)
 
-        generate_recipe(recipe, config, args.output)
+        generate_recipe(recipe, config, args.output, args.use_v1_format)
         print_msg(
             f"\n{Fore.GREEN}#### Recipe generated on "
             f"{os.path.realpath(args.output)} for {pkg_name} ####\n\n"

grayskull/utils.py

@@ -7,10 +7,12 @@
 from difflib import SequenceMatcher
 from functools import lru_cache
 from glob import glob
+from io import StringIO
 from pathlib import Path
 from shutil import copyfile
 from typing import List, Optional, Union
 
+from conda_recipe_manager.parser.recipe_parser_convert import RecipeParserConvert
 from ruamel.yaml import YAML
 from ruamel.yaml.comments import CommentedMap
 from souschef.recipe import Recipe
@@ -194,11 +196,13 @@ def generate_recipe(
     recipe: Recipe,
     config,
     folder_path: Union[str, Path] = ".",
+    use_v1_format: bool = False,
 ):
     """Write the recipe in a location. It will create a folder with the
     package name and the recipe will be there.
 
     :param folder_path: Path to the folder
+    :param use_v1_format: If set to True, return a recipe in the V1 format
     """
     if recipe["package"]["name"].value.startswith("r-{{"):
         pkg_name = f"r-{config.name}"
@@ -215,18 +219,40 @@ def generate_recipe(
         logging.debug(f"Generating recipe on: {recipe_dir}")
         if not recipe_dir.is_dir():
             recipe_dir.mkdir()
-        recipe_path = recipe_dir / "meta.yaml"
+        recipe_path = recipe_dir / "recipe.yaml" if use_v1_format else "meta.yaml"
         recipe_folder = recipe_dir
         add_new_lines_after_section(recipe.yaml)
 
     clean_yaml(recipe)
-    recipe.save(recipe_path)
+    if use_v1_format:
+        # Write the converted recipe straight to disk to avoid having convert-back
+        # to a data-type that will not be used past this point.
+        upgrade_v0_recipe_to_v1(recipe, recipe_path)
+    else:
+        recipe.save(recipe_path)
     for file_to_recipe in config.files_to_copy:
         name = file_to_recipe.split(os.path.sep)[-1]
         if os.path.isfile(file_to_recipe):
             copyfile(file_to_recipe, os.path.join(recipe_folder, name))
 
 
+def upgrade_v0_recipe_to_v1(recipe: Recipe, recipe_path: Path) -> None:
+    """
+    Takes a V0 (pre CEP-13) recipe and converts it to a V1 (post CEP-13) recipe file.
+    Upgraded recipes are saved to the provided file path.
+    :param recipe: Recipe data structure to convert
+    :param recipe_path: Path to write the converted recipe file
+    """
+    recipe_stream = StringIO()
+    yaml.dump(recipe.yaml, recipe_stream)
+    recipe_content = recipe_stream.getvalue()
+    recipe_stream.close()
+
+    recipe_converter = RecipeParserConvert(recipe_content)
+    v1_content, _, _ = recipe_converter.render_to_v1_recipe_format()
+    recipe_path.write_text(v1_content, encoding="utf-8")
+
+
 def add_new_lines_after_section(recipe_yaml: CommentedMap) -> CommentedMap:
     for section in recipe_yaml.keys():
         if section == "package":