feat(webui): gated action framework (#434)

Register future write actions with task_capability_map metadata, mutation-ledger previews, and fail-closed execution in the read-only MVP. Adds /actions routes, disabled UI buttons, and tests proving ungated attempts cannot invoke mutations. Closes #434
2026-07-07 15:34:39 -04:00
parent ee8e9a0247
commit 84b841c727
7 changed files with 505 additions and 5 deletions
@@ -0,0 +1,201 @@
+"""Disabled-by-default gated action registry for future UI writes (#434).
+
+Every action declares the MCP capability and profile role from
+``task_capability_map``. Previews always render a mutation ledger; execution
+is fail-closed in the read-only MVP (no MCP or shell fallbacks).
+"""
+
+from __future__ import annotations
+
+from dataclasses import asdict, dataclass, field
+from typing import Any
+
+from task_capability_map import required_permission, required_role
+
+# MVP: no UI action may execute mutations until capability gates ship.
+_MVP_ACTIONS_ENABLED = False
+
+
+@dataclass(frozen=True)
+class MutationLedgerEntry:
+    """One planned mutation step shown before any write executes."""
+
+    sequence: int
+    mcp_tool: str
+    permission: str
+    target: str
+    summary: str
+
+
+@dataclass(frozen=True)
+class GatedAction:
+    """Registry entry tying a UI action to resolver task metadata."""
+
+    action_id: str
+    label: str
+    task_key: str
+    mcp_tool: str
+    description: str
+    enabled: bool = False
+
+    @property
+    def required_permission(self) -> str:
+        return required_permission(self.task_key)
+
+    @property
+    def required_role(self) -> str:
+        return required_role(self.task_key)
+
+    def mutation_ledger(self, **params: Any) -> tuple[MutationLedgerEntry, ...]:
+        """Build the mutation ledger preview for *params* (read-only)."""
+        target = _format_target(self.action_id, params)
+        return (
+            MutationLedgerEntry(
+                sequence=1,
+                mcp_tool=self.mcp_tool,
+                permission=self.required_permission,
+                target=target,
+                summary=self.description,
+            ),
+        )
+
+    def preview(self, **params: Any) -> dict[str, Any]:
+        ledger = self.mutation_ledger(**params)
+        return {
+            "action_id": self.action_id,
+            "label": self.label,
+            "task_key": self.task_key,
+            "mcp_tool": self.mcp_tool,
+            "required_permission": self.required_permission,
+            "required_role": self.required_role,
+            "enabled": self.enabled and _MVP_ACTIONS_ENABLED,
+            "mvp_mode": "read-only",
+            "mutation_ledger": [asdict(entry) for entry in ledger],
+            "params": dict(params),
+        }
+
+    def attempt(self, **params: Any) -> dict[str, Any]:
+        """Fail closed — never invokes MCP tools in MVP."""
+        preview = self.preview(**params)
+        if not preview["enabled"]:
+            return {
+                "success": False,
+                "error": "action_disabled",
+                "detail": (
+                    "UI actions are disabled in the read-only MVP. "
+                    "Use MCP tools with capability gates."
+                ),
+                "preview": preview,
+            }
+        return {
+            "success": False,
+            "error": "action_not_implemented",
+            "detail": "Gated execution path is not wired in MVP.",
+            "preview": preview,
+        }
+
+
+def _format_target(action_id: str, params: dict[str, Any]) -> str:
+    if action_id == "claim_issue":
+        return f"issue #{params.get('issue_number', '?')}"
+    if action_id in {"comment_issue", "close_issue"}:
+        return f"issue #{params.get('issue_number', '?')}"
+    if action_id in {"review_pr", "merge_pr", "comment_pr", "close_pr"}:
+        return f"PR #{params.get('pr_number', '?')}"
+    if action_id == "delete_branch":
+        return f"branch {params.get('branch_name', '?')!r}"
+    if action_id == "create_pr":
+        return (
+            f"PR {params.get('head', '?')} → {params.get('base', 'master')}"
+        )
+    if action_id == "create_issue":
+        return f"issue {params.get('title', '?')!r}"
+    return "unspecified"
+
+
+@dataclass
+class ActionRegistry:
+    """Ordered registry of gated UI actions."""
+
+    actions: tuple[GatedAction, ...] = field(default_factory=tuple)
+
+    def get(self, action_id: str) -> GatedAction | None:
+        for action in self.actions:
+            if action.action_id == action_id:
+                return action
+        return None
+
+    def to_dict(self) -> dict[str, Any]:
+        return {
+            "mvp_actions_enabled": _MVP_ACTIONS_ENABLED,
+            "actions": [
+                {
+                    "action_id": action.action_id,
+                    "label": action.label,
+                    "task_key": action.task_key,
+                    "mcp_tool": action.mcp_tool,
+                    "required_permission": action.required_permission,
+                    "required_role": action.required_role,
+                    "enabled": action.enabled,
+                    "description": action.description,
+                }
+                for action in self.actions
+            ],
+        }
+
+
+def build_action_registry() -> ActionRegistry:
+    """Return the canonical MVP action set (all disabled)."""
+    specs = (
+        ("claim_issue", "Claim issue", "claim_issue", "gitea_mark_issue",
+         "Apply status:in-progress via issue comment gate."),
+        ("comment_issue", "Comment on issue", "comment_issue",
+         "gitea_create_issue_comment", "Post an issue comment."),
+        ("create_issue", "Create issue", "create_issue", "gitea_create_issue",
+         "Open a new tracking issue."),
+        ("create_pr", "Create pull request", "create_pr", "gitea_create_pr",
+         "Open a PR from a locked feature branch."),
+        ("review_pr", "Review PR", "review_pr", "gitea_review_pr",
+         "Submit approve/request-changes/comment review."),
+        ("merge_pr", "Merge PR", "merge_pr", "gitea_merge_pr",
+         "Merge an approved pull request."),
+        ("delete_branch", "Delete branch", "delete_branch",
+         "gitea_delete_branch", "Remove a remote feature branch."),
+        ("comment_pr", "Comment on PR", "comment_pr",
+         "gitea_create_issue_comment", "Post a PR review thread comment."),
+        ("close_pr", "Close PR", "close_pr", "gitea_edit_pr",
+         "Close a pull request without merge."),
+    )
+    actions = tuple(
+        GatedAction(
+            action_id=action_id,
+            label=label,
+            task_key=task_key,
+            mcp_tool=mcp_tool,
+            description=description,
+            enabled=False,
+        )
+        for action_id, label, task_key, mcp_tool, description in specs
+    )
+    return ActionRegistry(actions=actions)
+
+
+_REGISTRY = build_action_registry()
+
+
+def load_action_registry() -> ActionRegistry:
+    return _REGISTRY
+
+
+def preview_action(action_id: str, **params: Any) -> dict[str, Any]:
+    action = _REGISTRY.get(action_id)
+    if action is None:
+        return {"error": "unknown_action", "action_id": action_id}
+    return action.preview(**params)
+
+
+def attempt_action(action_id: str, **params: Any) -> dict[str, Any]:
+    action = _REGISTRY.get(action_id)
+    if action is None:
+        return {"success": False, "error": "unknown_action", "action_id": action_id}
+    return action.attempt(**params)