Simplify template candidate confirmation and direct batch backtesting

backend/app/research/experiments.py

@@ -7,14 +7,14 @@ from collections import defaultdict
 from fastapi import HTTPException
 from sqlalchemy import func, select, update
 
-from ..backtests.contracts import Candidate, DraftInput, PreviewInput, SimulationSettings, Source
+from ..backtests.contracts import Candidate, DraftInput, PreviewInput, SimulationSettings, Source, StartInput
 from ..backtests.service import Backtests, uid
 from ..catalog.research_metadata import ResearchMetadata
 from ..catalog.service import Catalog
-from ..models import Alpha, BacktestRun, CatalogResource, ResearchExperiment
+from ..models import Account, Alpha, BacktestPreview, BacktestRun, CatalogResource, ResearchExperiment
 from ..preparations.service import Preparations
 from .assets import Assets
-from .expressions import GROUPS, analyze, expand
+from .expressions import GROUPS, ExpressionError, Parser, analyze, expand
 from .serialization import encode_snapshot as jsonable_encoder
 from .workspace_contracts import TemplateSpec
 
@@ -45,7 +45,7 @@ class Experiments:
         self.catalog = Catalog(db)
         self.assets = Assets(db)
 
-    async def inputs(self, ids, scope=None):
+    async def inputs(self, ids, scope=None, *, check_types=True):
         if len(set(ids)) != len(ids):
             raise HTTPException(422, "输入快照重复")
         snapshots = [await self.catalog.input(input_id) for input_id in ids]
@@ -56,7 +56,7 @@ class Experiments:
             for name, kind in item["field_types"].items():
                 if name not in item["field_ids"]:
                     continue
-                if name in fields and fields[name] != kind:
+                if check_types and name in fields and fields[name] != kind:
                     raise HTTPException(422, f"字段 {name} 在不同快照中类型不一致")
                 fields[name] = kind
         return snapshots, fields
@@ -138,7 +138,9 @@ class Experiments:
         asset = await self.assets.get(body.asset_id, body.version, "template") if body.asset_id else None
         template = TemplateSpec.model_validate(asset["content"]) if asset else body.template
         scope = scope_of(body.settings)
-        snapshots, fields = await self.inputs(body.input_ids, scope)
+        snapshots, fields = await self.inputs(body.input_ids, scope, check_types=kind != "template")
+        if kind == "template" and not snapshots:
+            raise HTTPException(422, "请先选择数据准备")
         parents = (
             parent_snapshots
             if parent_snapshots is not None
@@ -155,9 +157,9 @@ class Experiments:
                 if not values:
                     raise HTTPException(422, f"变量 {name} 没有匹配的 {variable.field_type} 字段，请调整数据准备")
                 for value in values:
-                    if fields.get(str(value)) != variable.field_type:
+                    if kind != "template" and fields.get(str(value)) != variable.field_type:
                         raise HTTPException(422, f"变量 {name} 的字段 {value} 不在固定输入中或类型不符")
-            if variable.kind == "group" and any(
+            if kind != "template" and variable.kind == "group" and any(
                 str(v) not in GROUPS and fields.get(str(v)) != "GROUP" for v in variable.values
             ):
                 raise HTTPException(422, f"分组变量 {name} 未在固定输入中核实")
@@ -170,16 +172,29 @@ class Experiments:
             expanded = expand(template.expression, variables, body.mode, body.limit, body.seed)
         except ValueError as exc:
             raise HTTPException(422, str(exc)) from None
-        operators_snapshot = await ResearchMetadata(self.db).get("operators")
-        operators = {item["name"] for item in operators_snapshot["content"].get("items", [])}
-        setting_errors, settings_snapshot = await self.settings_check(body.settings)
-        availability = await self.field_evidence(scope, fields)
+        validation_evidence = {}
+        if kind != "template":
+            operators_snapshot = await ResearchMetadata(self.db).get("operators")
+            operators = {item["name"] for item in operators_snapshot["content"].get("items", [])}
+            setting_errors, settings_snapshot = await self.settings_check(body.settings)
+            availability = await self.field_evidence(scope, fields)
+            validation_evidence = {
+                "field_availability": availability,
+                "availability_basis": "各输入的已发布范围目录；若另有字段级证据，须同时满足",
+                "operators_snapshot": operators_snapshot,
+                "settings_snapshot": settings_snapshot,
+            }
         candidates = []
         for index, item in enumerate(expanded["items"]):
-            validation = self.validate(item["expression"], fields, operators, scope, availability)
-            validation["availability"].extend(setting_errors)
-            if setting_errors and validation["status"] == "valid":
-                validation["status"] = "needs_review"
+            findings = {}
+            if kind == "template":
+                self.check_syntax(item["expression"], f"候选 {index + 1}")
+            else:
+                validation = self.validate(item["expression"], fields, operators, scope, availability)
+                validation["availability"].extend(setting_errors)
+                if setting_errors and validation["status"] == "valid":
+                    validation["status"] = "needs_review"
+                findings["validation"] = validation
             candidates.append(
                 {
                     **Candidate(
@@ -187,7 +202,7 @@ class Experiments:
                     ).model_dump(mode="json"),
                     "bindings": item["bindings"],
                     "input_ids": list(body.input_ids),
-                    "validation": validation,
+                    **findings,
                     "changes": [
                         self.diff(parent.get("expression", ""), item["expression"])
                         for parent in parents
@@ -197,16 +212,21 @@ class Experiments:
             )
         evidence = {
             "template": asset or {"content": template.model_dump(mode="json")},
-            "field_availability": availability,
-            "availability_basis": "各输入的已发布范围目录；若另有字段级证据，须同时满足",
             "combination_count": expanded["combination_count"],
             "seed": expanded["seed"],
-            "operators_snapshot": operators_snapshot,
-            "settings_snapshot": settings_snapshot,
+            **validation_evidence,
             **(extra_evidence or {}),
         }
         return await self.save(template.name, kind, body.hypothesis, snapshots, parents, candidates, evidence)
 
+    @staticmethod
+    def check_syntax(expression, label="表达式"):
+        """Reject unsupported syntax before persistence; platform semantics are not inferred."""
+        try:
+            Parser(expression).parse()
+        except (ExpressionError, RecursionError) as exc:
+            raise HTTPException(422, f"{label}语法错误：{exc}") from None
+
     @staticmethod
     def diff(before, after):
         return [
@@ -314,11 +334,20 @@ class Experiments:
             candidates = [item for item in candidates if item["client_item_id"] in chosen]
             if len(candidates) != len(chosen):
                 raise HTTPException(422, "选择包含未知候选")
-        else:
+        elif experiment["kind"] != "template":
             candidates = [item for item in candidates if item["validation"]["status"] == "valid"]
-        if not candidates or any(item["validation"]["status"] != "valid" for item in candidates):
+        if not candidates:
+            raise HTTPException(422, "请至少选择一条候选")
+        if experiment["kind"] != "template" and any(item["validation"]["status"] != "valid" for item in candidates):
             raise HTTPException(422, "候选存在语法、类型或可用性问题，请先解决；至少保留一条已核实候选")
         inputs = experiment["inputs"]
+        if experiment["kind"] == "template":
+            # Historical collections follow the same syntax/scope contract; old row findings are irrelevant.
+            for candidate in candidates:
+                self.check_syntax(candidate["expression"], candidate["client_item_id"])
+                scope = scope_of(SimulationSettings.model_validate(candidate["settings"]))
+                if not inputs or any(item["scope"] != scope for item in inputs):
+                    raise HTTPException(422, "数据准备与回测参数组合不一致，请重新生成候选集合")
         return await Backtests(self.db).preview(
             PreviewInput(
                 inline=DraftInput(
@@ -345,6 +374,35 @@ class Experiments:
             preserve_source=True,
         )
 
+    async def start_template_backtest(self, experiment_id, body):
+        """Start the explicitly selected immutable collection in the caller's transaction.
+
+        Account locking covers preview creation as well as run creation, so concurrent
+        retries share one run. Reusing a key for another collection/selection raises 409.
+        The caller must wake the runner only after committing this transaction.
+        """
+        chosen = set(body.candidate_ids)
+        if len(chosen) != len(body.candidate_ids):
+            raise HTTPException(422, "候选选择包含重复项")
+        await self.db.scalar(select(Account).where(Account.id == 1).with_for_update())
+        previous = await self.db.scalar(select(BacktestRun).where(BacktestRun.idempotency_key == body.idempotency_key))
+        if previous:
+            saved = await self.db.get(BacktestPreview, previous.preview_id)
+            if previous.source.get("research_id") != experiment_id or chosen != {
+                c["client_item_id"] for c in saved.candidates
+            }:
+                raise HTTPException(409, "幂等键已用于另一候选集合或选择")
+            return await Backtests(self.db).run(previous.id)
+        experiment = await self.get(experiment_id)
+        if experiment["kind"] != "template":
+            raise HTTPException(422, "此入口仅用于模板候选集合")
+        if experiment["archived"]:
+            raise HTTPException(409, "候选集合已删除")
+        preview = await self.preview(experiment_id, body.candidate_ids)
+        return await Backtests(self.db).start(StartInput(
+            preview_id=preview["preview_id"], version=preview["version"], idempotency_key=body.idempotency_key,
+        ))
+
     async def setting_variants(self, body, *, parent_snapshot=None, extra_evidence=None, kind="variant"):
         parents = (
             [parent_snapshot] if parent_snapshot is not None else await self.parents([body.alpha_id], [])