CI: Update workflows and templates to expect json files

Update GitHub and CircleCI settings to check for json files.

Update `check_description_files` CLI to parse json files:
* Remove `parse_s4ext` and introduce `parse_json` function along with
  `ExtensionParseError` exception.
* Update list of supported URL schemes. Only `https` and `git` are supported
* Remove obsolete `check_scm_notlocal` check

.circleci/config.yml

@@ -19,7 +19,7 @@ jobs:
       - run:
           name: Check description files
           command: |
-            python ./scripts/check_description_files.py --check-dependencies . $(find . -name "*.s4ext")
+            python ./scripts/check_description_files.py --check-dependencies . $(find . -maxdepth 1 -name "*.json")
 
   check-new-description-files:
     docker:
@@ -50,8 +50,8 @@ jobs:
             echo "BASE_BRANCH is [$BASE_BRANCH]"
             echo "CIRCLE_BRANCH is [$CIRCLE_BRANCH]"
 
-            # Collect list of new *.s4ext files
-            added=$(git diff $BASE_BRANCH --diff-filter=A --name-only | grep -E "^[^\/]+\.s4ext$")
+            # Collect list of new *.json files
+            added=$(git diff $BASE_BRANCH --diff-filter=A --name-only | grep -E "^[^\/]+\.json$")
             echo "added [$added]"
 
             # Run checks

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,7 +1,7 @@
 <!--
 Thank you for contributing to 3D Slicer!
 - To add a new extension with this pull request: Please keep content of "New extension" section and put an 'x' in the brackets for each todo item to indicate that you have accomplished that prerequisite.
-- To update an existing extension with this pull request: Please delete all text in this template and just describe which extension is updated and optionally tell us in a sentence what has been changed. To make extension updates easier in the future you may consider replacing specific git hash in your s4ext file by a branch name (for example: `main` for Slicer Preview Releases; `(majorVersion).(minorVersion)` such as `4.10` for Slicer Stable Releases).
+- To update an existing extension with this pull request: Please delete all text in this template and just describe which extension is updated and optionally tell us in a sentence what has been changed. To make extension updates easier in the future you may consider replacing specific git hash in your json file by a branch name (for example: `main` for Slicer Preview Releases; `(majorVersion).(minorVersion)` such as `5.6` for Slicer Stable Releases).
 -->
 
 # New extension
@@ -25,7 +25,7 @@ Thank you for contributing to 3D Slicer!
   - [ ] Tutorial: step-by-step description of at least the most typical use case, include a few screenshots, provide download links to sample input data set
   - [ ] Publication: link to publication and/or to PubMed reference (if available)
   - [ ] License: We suggest you use a permissive license that includes patent and contribution clauses.  This will help protect developers and ensure the code remains freely available.  We suggest you use the [Slicer License](https://github.com/Slicer/Slicer/blob/main/License.txt) or the [Apache 2.0](https://www.apache.org/licenses/LICENSE-2.0). Always mention in your README file the license you have chosen.  If you choose a different license, explain why to the extension maintainers. Depending on the license we may not be able to host your work. Read [here](https://opensource.guide/legal/#which-open-source-license-is-appropriate-for-my-project) to learn more about licenses.
-  - [ ] Content of submitted s4ext file is consistent with the top-level CMakeLists.txt file in the repository (description, URLs, dependencies, etc. are the same)
+  - [ ] Content of submitted json file is consistent with the top-level CMakeLists.txt file in the repository (dependencies, etc. are the same)
 - Hide unused features in the repository to reduce noise/irrelevant information:
   - [ ] Click `Settings` and in repository settings uncheck `Wiki`, `Projects`, and `Discussions` (if they are currently not used)
   - [ ] Click the settings icon next to `About` in the top-right corner of the repository main page and uncheck `Releases` and `Packages` (if they are currently not used)

scripts/check_description_files.py

@@ -5,6 +5,7 @@
 """
 
 import argparse
+import json
 import os
 import sys
 import textwrap
@@ -13,6 +14,17 @@
 from functools import wraps
 
 
+class ExtensionParseError(RuntimeError):
+    """Exception raised when a particular extension description file failed to be parsed.
+    """
+    def __init__(self, extension_name, details):
+        self.extension_name = extension_name
+        self.details = details
+
+    def __str__(self):
+        return self.details
+
+
 class ExtensionCheckError(RuntimeError):
     """Exception raised when a particular extension check failed.
     """
@@ -40,20 +52,21 @@ def wrapped(*args, **kwargs):
     return dec
 
 
-def parse_s4ext(ext_file_path):
+def parse_json(ext_file_path):
     """Parse a Slicer extension description file.
-    :param ext_file_path: Path to a Slicer extension description file.
+    :param ext_file_path: Path to a Slicer extension description file (.json).
     :return: Dictionary of extension metadata.
     """
-    ext_metadata = {}
-    with open(ext_file_path) as ext_file:
-        for line in ext_file:
-            if not line.strip() or line.startswith("#"):
-                continue
-            fields = [field.strip() for field in line.split(' ', 1)]
-            assert(len(fields) <= 2)
-            ext_metadata[fields[0]] = fields[1] if len(fields) == 2 else None
-    return ext_metadata
+    with open(ext_file_path) as input_file:
+        try:
+            return json.load(input_file)
+        except json.JSONDecodeError as exc:
+            extension_name = os.path.splitext(os.path.basename(ext_file_path))[0]
+            raise ExtensionParseError(
+                extension_name,
+                textwrap.dedent("""
+                Failed to parse '%s': %s
+                """ % (ext_file_path, exc)))
 
 
 @require_metadata_key("scmurl")
@@ -63,29 +76,20 @@ def check_scmurl_syntax(extension_name, metadata):
     if "://" not in metadata["scmurl"]:
         raise ExtensionCheckError(extension_name, check_name, "scmurl do not match scheme://host/path")
 
-    supported_schemes = ["git", "https", "svn"]
+    supported_schemes = ["git", "https"]
     scheme = urlparse.urlsplit(metadata["scmurl"]).scheme
     if scheme not in supported_schemes:
         raise ExtensionCheckError(
             extension_name, check_name,
             "scmurl scheme is '%s' but it should by any of %s" % (scheme, supported_schemes))
 
-@require_metadata_key("scm")
-def check_scm_notlocal(extension_name, metadata):
-    check_name = "check_scm_notlocal"
-    if metadata["scm"] == "local":
-        raise ExtensionCheckError(extension_name, check_name, "scm cannot be local")
 
 @require_metadata_key("scmurl")
-@require_metadata_key("scm")
 def check_git_repository_name(extension_name, metadata):
     """See https://www.slicer.org/wiki/Documentation/Nightly/Developers/FAQ#Should_the_name_of_the_source_repository_match_the_name_of_the_extension_.3F
     """
     check_name = "check_git_repository_name"
 
-    if metadata["scm"] != "git":
-        return
-
     repo_name = os.path.splitext(urlparse.urlsplit(metadata["scmurl"]).path.split("/")[-1])[0]
 
     if not repo_name.startswith("Slicer"):
@@ -106,18 +110,19 @@ def check_dependencies(directory):
     available_extensions = []
     for filename in os.listdir(directory):
         f = os.path.join(directory, filename)
-        if not os.path.isfile(f):
+        if not os.path.isfile(f) or not filename.endswith(".json"):
             continue
         extension_name = os.path.splitext(os.path.basename(filename))[0]
         available_extensions.append(extension_name)
-        extension_description = parse_s4ext(f)
+        try:
+            extension_description = parse_json(f)
+        except ExtensionParseError as exc:
+            print(exc)
+            continue
         if 'depends' not in extension_description:
             continue
-        dependencies = extension_description['depends'].split(' ')
+        dependencies = extension_description['depends']
         for dependency in dependencies:
-            if dependency == 'NA':
-                # special value, just a placeholder that must be ignored
-                continue
             if dependency in required_extensions:
                 required_extensions[dependency].append(extension_name)
             else:
@@ -140,7 +145,7 @@ def main():
         "--check-git-repository-name", action="store_true",
         help="Check extension git repository name. Disabled by default.")
     parser.add_argument("-d", "--check-dependencies", help="Check all extension dsecription files in the provided folder.")
-    parser.add_argument("/path/to/description.s4ext", nargs='*')
+    parser.add_argument("/path/to/extension_name.json", nargs='*')
     args = parser.parse_args()
 
     checks = []
@@ -151,27 +156,31 @@ def main():
     if not checks:
         checks = [
             check_scmurl_syntax,
-            check_scm_notlocal,
         ]
 
     total_failure_count = 0
 
-    file_paths = getattr(args, "/path/to/description.s4ext")
+    file_paths = getattr(args, "/path/to/extension_name.json")
     for file_path in file_paths:
         extension_name = os.path.splitext(os.path.basename(file_path))[0]
 
         failures = []
 
-        metadata = parse_s4ext(file_path)
-        for check in checks:
-            try:
-                check(extension_name, metadata)
-            except ExtensionCheckError as exc:
-                failures.append(str(exc))
+        try:
+            metadata = parse_json(file_path)
+        except ExtensionParseError as exc:
+            failures.append(str(exc))
+
+        if not failures:
+            for check in checks:
+                try:
+                    check(extension_name, metadata)
+                except ExtensionCheckError as exc:
+                    failures.append(str(exc))
 
         if failures:
             total_failure_count += len(failures)
-            print("%s.s4ext" % extension_name)
+            print("%s.json" % extension_name)
             for failure in set(failures):
                 print("  %s" % failure)
 

scripts/check_filenames.sh

@@ -18,12 +18,13 @@ unexpected_files=$(find . -mindepth 1 \( -type d \( \
   -path ./.github -o \
   -path ./.git -o \
   -path ./ARCHIVE -o \
+  -path ./resources -o \
   -path ./scripts \
 \) -o -type f \( \
   -name .pre-commit-config.yaml -o \
   -name .git-blame-ignore-revs  -o \
   -name README.md -o \
-  -name "*.s4ext" \
+  -name "*.json" \
 \)  \)  -prune -o -print)
 
 for unexpected_file in $unexpected_files; do