Add `--extension` flag to `specify init` for opting into extensions at init time by Copilot · Pull Request #2396 · github/spec-kit

Copilot · 2026-04-28T17:58:37Z

No way to install extensions during specify init — the git extension is hardcoded to auto-install, and everything else requires a separate specify extension add post-init. This adds a repeatable --extension flag so users can opt into extensions at init time (prerequisite for git no longer being enabled by default in 1.0.0).

Changes

`_install_extension_during_init` helper

New function that auto-detects source type and delegates accordingly:

Bundled name (git, selftest) — checks bundled package first, falls back to catalog; skips if already installed
Local path — triggers on ./, ../, /, ~/, .\, ..\ prefixes or any Path.is_absolute() match (Windows-safe)
HTTPS URL — downloads ZIP, enforces HTTPS (localhost HTTP allowed), cleans up after install
Raises ValueError on failure; caller converts to tracker error without aborting init

`specify init` updates

Added --extension as a repeatable list[str] | None typer option
Tracker steps pre-registered as extension-{i} before the Live context; installed after workflow, before final step
Extension failures are non-fatal (recorded in tracker, init continues)

Usage

# Bundled extension by name
specify init my-project --integration copilot --extension git

# Multiple extensions
specify init my-project --extension git --extension selftest

# Local path
specify init my-project --extension ./my-extensions/custom-ext

# URL
specify init my-project --extension https://example.com/extensions/my-ext.zip

Tests

Five new tests in TestExtensionFlag: bundled name, multiple extensions, local absolute path, unknown extension (graceful error, no abort), and combined with --preset.

…t time Agent-Logs-Url: https://github.com/github/spec-kit/sessions/ddeae546-8287-421f-bc5d-1636515bf99a Co-authored-by: mnriem <15701806+mnriem@users.noreply.github.com>

Agent-Logs-Url: https://github.com/github/spec-kit/sessions/ddeae546-8287-421f-bc5d-1636515bf99a Co-authored-by: mnriem <15701806+mnriem@users.noreply.github.com>

Copilot

Pull request overview

Adds a repeatable --extension flag to specify init so users can opt into installing extensions (bundled IDs, local paths, or URLs) as part of project initialization, instead of requiring a separate specify extension add step.

Changes:

Introduces _install_extension_during_init() to install an extension from a name/ID, local directory path, or URL.
Extends specify init with a repeatable --extension option and tracker steps to install requested extensions non-fatally.
Adds CLI-level tests covering bundled, multiple, local-path, unknown extension handling, and interaction with --preset.

Show a summary per file

File	Description
`src/specify_cli/__init__.py`	Adds the init-time extension install helper and wires `--extension` into `specify init` with tracker integration.
`tests/integrations/test_cli.py`	Adds `TestExtensionFlag` to validate init-time extension installation and failure behavior.

Copilot's findings

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Comments suppressed due to low confidence (1)

src/specify_cli/init.py:974

In _install_extension_during_init, the import list includes ExtensionError, ValidationError, and CompatibilityError but none of them are used in this helper. Either remove these imports or use them to normalize errors (e.g., catch and re-raise as ValueError) to match the function’s contract and keep the helper clean.

    from urllib.parse import urlparse
    from .extensions import ExtensionManager, ExtensionCatalog, ExtensionError, ValidationError, CompatibilityError

Files reviewed: 2/2 changed files
Comments generated: 4

Copilot · 2026-04-28T19:28:37Z

+    """Install a single extension during ``specify init``.
+
+    Handles bundled extension names, local directory paths, and HTTPS URLs.
+    Returns a short status message on success.
+    Raises ``ValueError`` on failure so the caller can convert it to a
+    tracker error without aborting the entire init.
+    """
+    from urllib.parse import urlparse
+    from .extensions import ExtensionManager, ExtensionCatalog, ExtensionError, ValidationError, CompatibilityError
+
+    manager = ExtensionManager(project_path)
+
+    # --- URL ---
+    parsed = urlparse(ext_spec)
+    if parsed.scheme in ("http", "https"):
+        is_localhost = parsed.hostname in ("localhost", "127.0.0.1", "::1")
+        if parsed.scheme != "https" and not (parsed.scheme == "http" and is_localhost):
+            raise ValueError("URL must use HTTPS (HTTP is only allowed for localhost)")
+
+        import urllib.request
+        import urllib.error as _urllib_error
+        download_dir = project_path / ".specify" / "extensions" / ".cache" / "downloads"
+        download_dir.mkdir(parents=True, exist_ok=True)
+        import re as _re
+        safe_name = _re.sub(r"[^a-z0-9-]", "-", (parsed.path.split("/")[-1] or "download").lower())[:64]
+        zip_path = download_dir / f"{safe_name}-init-download.zip"
+        try:
+            with urllib.request.urlopen(ext_spec, timeout=60) as _resp:
+                zip_path.write_bytes(_resp.read())
+            manifest = manager.install_from_zip(zip_path, speckit_version)
+        except _urllib_error.URLError as exc:
+            raise ValueError(f"Failed to download from {ext_spec}: {exc}") from exc
+        finally:
+            zip_path.unlink(missing_ok=True)
+        return f"{manifest.name} v{manifest.version} installed"
+
+    # --- Local path ---
+    if ext_spec.startswith(("./", "../", "/", "~/", ".\\", "..\\")) or Path(ext_spec).is_absolute():
+        source_path = Path(ext_spec).expanduser().resolve()
+        if not source_path.exists():
+            raise ValueError(f"Directory not found: {source_path}")
+        if not (source_path / "extension.yml").exists():
+            raise ValueError(f"No extension.yml found in {source_path}")
+        manifest = manager.install_from_directory(source_path, speckit_version)
+        return f"{manifest.name} v{manifest.version} installed"


The docstring says this helper “Raises ValueError on failure”, but several calls inside it can raise ExtensionError / ValidationError / CompatibilityError (e.g., install_from_directory / install_from_zip) and those currently propagate. Either adjust the docstring/typing to reflect the real exceptions or catch the extension-specific exceptions and re-raise as ValueError so callers get consistent behavior.

This issue also appears on line 972 of the same file.

Copilot · 2026-04-28T19:28:37Z

+        import urllib.request
+        import urllib.error as _urllib_error
+        download_dir = project_path / ".specify" / "extensions" / ".cache" / "downloads"
+        download_dir.mkdir(parents=True, exist_ok=True)
+        import re as _re
+        safe_name = _re.sub(r"[^a-z0-9-]", "-", (parsed.path.split("/")[-1] or "download").lower())[:64]
+        zip_path = download_dir / f"{safe_name}-init-download.zip"
+        try:
+            with urllib.request.urlopen(ext_spec, timeout=60) as _resp:


For --extension https://… installs, this uses urllib.request.urlopen() directly. Elsewhere (e.g., ExtensionCatalog._open_url) the codebase uses specify_cli._github_http.open_github_url() to attach GitHub auth when appropriate and strip it on redirects (preventing token leakage) while still supporting private GitHub URLs. Consider reusing that helper here for consistent behavior and safer redirect handling.

Suggested change

import urllib.request

import urllib.error as _urllib_error

download_dir = project_path / ".specify" / "extensions" / ".cache" / "downloads"

download_dir.mkdir(parents=True, exist_ok=True)

import re as _re

safe_name = _re.sub(r"[^a-z0-9-]", "-", (parsed.path.split("/")[-1] or "download").lower())[:64]

zip_path = download_dir / f"{safe_name}-init-download.zip"

try:

with urllib.request.urlopen(ext_spec, timeout=60) as _resp:

import urllib.error as _urllib_error

import re as _re

from ._github_http import open_github_url

download_dir = project_path / ".specify" / "extensions" / ".cache" / "downloads"

download_dir.mkdir(parents=True, exist_ok=True)

safe_name = _re.sub(r"[^a-z0-9-]", "-", (parsed.path.split("/")[-1] or "download").lower())[:64]

zip_path = download_dir / f"{safe_name}-init-download.zip"

try:

with open_github_url(ext_spec, timeout=60) as _resp:

Copilot · 2026-04-28T19:28:38Z

+    # --- Local path ---
+    if ext_spec.startswith(("./", "../", "/", "~/", ".\\", "..\\")) or Path(ext_spec).is_absolute():
+        source_path = Path(ext_spec).expanduser().resolve()
+        if not source_path.exists():
+            raise ValueError(f"Directory not found: {source_path}")
+        if not (source_path / "extension.yml").exists():
+            raise ValueError(f"No extension.yml found in {source_path}")
+        manifest = manager.install_from_directory(source_path, speckit_version)
+        return f"{manifest.name} v{manifest.version} installed"


This helper skips already-installed extensions only for the bundled-name path. For local-path and URL installs, ExtensionManager.install_from_directory/zip will raise ExtensionError if the extension is already installed, which will mark the init step as failed even though it’s a benign state (and can happen if the same extension is passed twice, or if init already installed it). Consider detecting “already installed” for these branches too (e.g., read the manifest id first or catch ExtensionError and treat it as a skip/already-installed status).

Copilot · 2026-04-28T19:28:38Z

+            # Install extensions specified via --extension
+            if extensions:
+                speckit_ver = get_speckit_version()
+                for i, ext_spec in enumerate(extensions):
+                    tracker.start(f"extension-{i}")


ensure_executable_scripts() runs before this new --extension install loop, but it explicitly scans .specify/extensions for .sh scripts. Installing extensions after that means extension-provided scripts won’t get execute bits set during init (and the chmod tracker step becomes misleading). Move the chmod step to after extension installs, or rerun ensure_executable_scripts() after the loop.

Initial plan

e3cf9d7

Copilot AI assigned Copilot and mnriem Apr 28, 2026

Copilot AI requested review from Copilot and removed request for Copilot April 28, 2026 17:58

Copilot started work on behalf of mnriem April 28, 2026 17:58 View session

Copilot AI linked an issue Apr 28, 2026 that may be closed by this pull request

Add --extension flag to specify init for opting into extensions at init time #2166

Open

4 tasks

Add --extension flag to specify init for installing extensions at ini…

a1543bc

…t time Agent-Logs-Url: https://github.com/github/spec-kit/sessions/ddeae546-8287-421f-bc5d-1636515bf99a Co-authored-by: mnriem <15701806+mnriem@users.noreply.github.com>

Copilot AI requested review from Copilot and removed request for Copilot April 28, 2026 18:09

Fix Windows absolute path detection and .zip example in docstring

b3f25da

Agent-Logs-Url: https://github.com/github/spec-kit/sessions/ddeae546-8287-421f-bc5d-1636515bf99a Co-authored-by: mnriem <15701806+mnriem@users.noreply.github.com>

Copilot AI requested review from Copilot and removed request for Copilot April 28, 2026 18:11

Copilot AI changed the title ~~[WIP] Add --extension flag to specify init for extensions~~ Add --extension flag to specify init for opting into extensions at init time Apr 28, 2026

Copilot finished work on behalf of mnriem April 28, 2026 18:12

Copilot AI requested a review from mnriem April 28, 2026 18:12

mnriem requested a review from Copilot April 28, 2026 19:23

Copilot started reviewing on behalf of mnriem April 28, 2026 19:24 View session

Copilot AI reviewed Apr 28, 2026

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Add `--extension` flag to `specify init` for opting into extensions at init time#2396

Add `--extension` flag to `specify init` for opting into extensions at init time#2396
Copilot wants to merge 3 commits intomainfrom
copilot/add-extension-flag-to-specify-init

Copilot AI commented Apr 28, 2026 •

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Copilot AI commented Apr 28, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

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Changes

_install_extension_during_init helper

specify init updates

Usage

Tests

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Copilot AI commented Apr 28, 2026 •

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`_install_extension_during_init` helper

`specify init` updates