migrate: remove model mappings and add aliases support

alembic/versions/20251214_1300_e9b3d63f0cbf_remove_model_mappings_add_aliases.py

@@ -0,0 +1,205 @@
+"""remove_model_mappings_add_aliases
+
+合并迁移：
+1. 添加 provider_model_aliases 字段到 models 表
+2. 迁移 model_mappings 数据到 provider_model_aliases
+3. 删除 model_mappings 表
+
+Revision ID: e9b3d63f0cbf
+Revises: 20251210_baseline
+Create Date: 2025-12-14 13:00:22.828183+00:00
+
+"""
+import json
+from datetime import datetime, timezone
+
+import sqlalchemy as sa
+from alembic import op
+from sqlalchemy.orm import Session
+
+
+# revision identifiers, used by Alembic.
+revision = 'e9b3d63f0cbf'
+down_revision = '20251210_baseline'
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    """添加 provider_model_aliases 字段，迁移数据，删除 model_mappings 表"""
+    # 1. 添加 provider_model_aliases 字段
+    op.add_column(
+        'models',
+        sa.Column('provider_model_aliases', sa.JSON(), nullable=True)
+    )
+
+    # 2. 迁移 model_mappings 数据
+    bind = op.get_bind()
+    session = Session(bind=bind)
+
+    model_mappings_table = sa.table(
+        "model_mappings",
+        sa.column("source_model", sa.String),
+        sa.column("target_global_model_id", sa.String),
+        sa.column("provider_id", sa.String),
+        sa.column("mapping_type", sa.String),
+        sa.column("is_active", sa.Boolean),
+    )
+
+    models_table = sa.table(
+        "models",
+        sa.column("id", sa.String),
+        sa.column("provider_id", sa.String),
+        sa.column("global_model_id", sa.String),
+        sa.column("provider_model_aliases", sa.JSON),
+        sa.column("updated_at", sa.DateTime(timezone=True)),
+    )
+
+    def normalize_alias_list(value) -> list[dict]:
+        """将 DB 返回的 JSON 值规范化为 list[{'name': str, 'priority': int}]"""
+        if value is None:
+            return []
+
+        if isinstance(value, str):
+            try:
+                value = json.loads(value) if value else []
+            except Exception:
+                return []
+
+        if not isinstance(value, list):
+            return []
+
+        normalized: list[dict] = []
+        for item in value:
+            if not isinstance(item, dict):
+                continue
+
+            raw_name = item.get("name")
+            if not isinstance(raw_name, str):
+                continue
+            name = raw_name.strip()
+            if not name:
+                continue
+
+            raw_priority = item.get("priority", 1)
+            try:
+                priority = int(raw_priority)
+            except Exception:
+                priority = 1
+            if priority < 1:
+                priority = 1
+
+            normalized.append({"name": name, "priority": priority})
+
+        return normalized
+
+    # 查询所有活跃的 provider 级别 alias（只迁移 is_active=True 且 mapping_type='alias' 的）
+    # 全局别名/映射不迁移（新架构不再支持 source_model -> GlobalModel.name 的解析）
+    mappings = session.execute(
+        sa.select(
+            model_mappings_table.c.source_model,
+            model_mappings_table.c.target_global_model_id,
+            model_mappings_table.c.provider_id,
+        )
+        .where(
+            model_mappings_table.c.is_active.is_(True),
+            model_mappings_table.c.provider_id.isnot(None),
+            model_mappings_table.c.mapping_type == "alias",
+        )
+        .order_by(model_mappings_table.c.provider_id, model_mappings_table.c.source_model)
+    ).all()
+
+    # 按 (provider_id, target_global_model_id) 分组，收集别名
+    alias_groups: dict = {}
+    for source_model, target_global_model_id, provider_id in mappings:
+        if not isinstance(source_model, str):
+            continue
+        source_model = source_model.strip()
+        if not source_model:
+            continue
+        if not isinstance(provider_id, str) or not provider_id:
+            continue
+        if not isinstance(target_global_model_id, str) or not target_global_model_id:
+            continue
+
+        key = (provider_id, target_global_model_id)
+        if key not in alias_groups:
+            alias_groups[key] = []
+        priority = len(alias_groups[key]) + 1
+        alias_groups[key].append({"name": source_model, "priority": priority})
+
+    # 更新对应的 models 记录
+    for (provider_id, global_model_id), aliases in alias_groups.items():
+        model_row = session.execute(
+            sa.select(models_table.c.id, models_table.c.provider_model_aliases)
+            .where(
+                models_table.c.provider_id == provider_id,
+                models_table.c.global_model_id == global_model_id,
+            )
+            .limit(1)
+        ).first()
+
+        if model_row:
+            model_id = model_row[0]
+            existing_aliases = normalize_alias_list(model_row[1])
+
+            existing_names = {a["name"] for a in existing_aliases}
+            merged_aliases = list(existing_aliases)
+            for alias in aliases:
+                name = alias.get("name")
+                if not isinstance(name, str):
+                    continue
+                name = name.strip()
+                if not name or name in existing_names:
+                    continue
+
+                merged_aliases.append(
+                    {
+                        "name": name,
+                        "priority": len(merged_aliases) + 1,
+                    }
+                )
+                existing_names.add(name)
+
+            session.execute(
+                models_table.update()
+                .where(models_table.c.id == model_id)
+                .values(
+                    provider_model_aliases=merged_aliases if merged_aliases else None,
+                    updated_at=datetime.now(timezone.utc),
+                )
+            )
+
+    session.commit()
+
+    # 3. 删除 model_mappings 表
+    op.drop_table('model_mappings')
+
+
+def downgrade() -> None:
+    """恢复 model_mappings 表，移除 provider_model_aliases 字段"""
+    # 1. 恢复 model_mappings 表
+    op.create_table(
+        'model_mappings',
+        sa.Column('id', sa.String(36), primary_key=True),
+        sa.Column('source_model', sa.String(200), nullable=False),
+        sa.Column(
+            'target_global_model_id',
+            sa.String(36),
+            sa.ForeignKey('global_models.id', ondelete='CASCADE'),
+            nullable=False,
+        ),
+        sa.Column('provider_id', sa.String(36), sa.ForeignKey('providers.id'), nullable=True),
+        sa.Column('mapping_type', sa.String(20), nullable=False, server_default='alias'),
+        sa.Column('is_active', sa.Boolean(), nullable=False, server_default='true'),
+        sa.Column('created_at', sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+        sa.Column('updated_at', sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+        sa.UniqueConstraint('source_model', 'provider_id', name='uq_model_mapping_source_provider'),
+    )
+    op.create_index('ix_model_mappings_source_model', 'model_mappings', ['source_model'])
+    op.create_index('ix_model_mappings_target_global_model_id', 'model_mappings', ['target_global_model_id'])
+    op.create_index('ix_model_mappings_provider_id', 'model_mappings', ['provider_id'])
+    op.create_index('ix_model_mappings_mapping_type', 'model_mappings', ['mapping_type'])
+
+    # 2. 移除 provider_model_aliases 字段
+    op.drop_column('models', 'provider_model_aliases')