Files
milvus/internal/rootcoord/ddl_callbacks_collection_function.go
5def5ced4a enhance: enforce function-field binding principle for function DDL (#51360)
## What

Enforce a function–field binding principle for function DDL (add / drop
/ alter function on an existing collection), so a function and its
output field stay coupled and already-stored vectors can never be
silently invalidated by DDL.

BM25 and MinHash follow the strict binding: add/drop only via the
unified `add_function_field` / `drop_function_field`, output field
always coupled. **TextEmbedding is a temporary carve-out** — its legacy
`AddCollectionFunction` / `DropCollectionFunction` paths are retained,
so attach-over-existing-field and detach are still possible for it,
because `add_function_field` embedding backfill is not yet implemented.
It will be folded into the unified path in a follow-up. So the "always
coupled" invariant currently holds for BM25/MinHash, not TextEmbedding.

## Changes

- **AlterCollectionSchema invariant**: reject standalone add-function (a
function must be added together with its new output field), reject
detaching a function without dropping its output field, and reject
function cascade (a new function's input being another function's
output).
- **Legacy RPCs**: `AddCollectionFunction` / `DropCollectionFunction`
are rejected for BM25/MinHash (must use `add_function_field` /
`drop_function_field`) and retained only for TextEmbedding (see
carve-out). `AlterCollectionFunction` is kept and gains the whitelist
below. In the alter and legacy-add paths, function field IDs are always
re-derived from field names (never trusted from the request), so a
request cannot inject an unrelated field ID that a later
`drop_function_field` would delete.
- **alter_function whitelist**: only connection/runtime params may
change (TextEmbedding: `url`, `credential`, `timeout_ms`,
`max_client_batch_size`, `region`, `location`, `projectid`, `user`);
BM25/MinHash have no alterable params. Function identity (type, name,
input/output fields) and output-shaping params (`dim`, `model_name`,
`endpoint` — the TEI model identity, `normalize`, `truncate*`, prompts,
...) are immutable. Params are normalized (keys lowercased, duplicate
keys rejected) so a crafted duplicate key cannot bypass the diff.
- **drop_function_field**: allow any output-producing function (dropping
needs no backfill), removing the previous BM25/MinHash-only restriction.

## Not in scope / follow-up

- Extending `add_function_field` to TextEmbedding (post-creation add
would require backfilling every existing row through the external
embedding model) — deferred; folding the TextEmbedding legacy paths into
the unified binding follows this.
- MinHash input-field analyzer immutability lives on a different DDL
path (`AlterCollectionField`); tracked as a separate follow-up.

## Breaking changes

- `DropCollectionFunction` on a **MinHash** function (detach — remove
the function but keep its output field) is no longer supported; use
`drop_function_field` instead (drops the function together with its
output field). If a released version supported MinHash detach, migrate
any such call to `drop_function_field`.

issue: #51348

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Signed-off-by: MrPresent-Han <chun.han@gmail.com>
Co-authored-by: MrPresent-Han <chun.han@gmail.com>
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-07-18 05:04:39 +08:00

206 lines
7.5 KiB
Go

// Licensed to the LF AI & Data foundation under one
// or more contributor license agreements. See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership. The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License. You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package rootcoord
import (
"context"
"google.golang.org/protobuf/types/known/fieldmaskpb"
"github.com/milvus-io/milvus-proto/go-api/v3/milvuspb"
"github.com/milvus-io/milvus-proto/go-api/v3/schemapb"
"github.com/milvus-io/milvus/internal/distributed/streaming"
"github.com/milvus-io/milvus/internal/metastore/model"
"github.com/milvus-io/milvus/internal/streamingcoord/server/broadcaster"
"github.com/milvus-io/milvus/internal/util/function/validator"
"github.com/milvus-io/milvus/pkg/v3/mlog"
"github.com/milvus-io/milvus/pkg/v3/proto/messagespb"
"github.com/milvus-io/milvus/pkg/v3/streaming/util/message"
"github.com/milvus-io/milvus/pkg/v3/util/merr"
"github.com/milvus-io/milvus/pkg/v3/util/typeutil"
)
const externalCollectionFunctionMutationUnsupportedMsg = "external collection does not support altering or dropping functions"
func rejectExternalCollectionFunctionMutation(schema *schemapb.CollectionSchema) error {
if typeutil.IsExternalCollection(schema) {
return merr.WrapErrParameterInvalidMsg(externalCollectionFunctionMutationUnsupportedMsg)
}
return nil
}
func callAlterCollection(ctx context.Context, c *Core, broadcaster broadcaster.BroadcastAPI, oldColl *model.Collection, newColl *model.Collection, dbName string, collectionName string) error {
// build new collection schema.
schema := newColl.ToCollectionSchemaPB()
schema.Version = newColl.SchemaVersion + 1
if err := typeutil.ValidateExternalCollectionResolvedSchema(schema); err != nil {
return err
}
cacheExpirations, err := c.getCacheExpireForCollection(ctx, dbName, collectionName)
if err != nil {
return err
}
header := &messagespb.AlterCollectionMessageHeader{
DbId: newColl.DBID,
CollectionId: newColl.CollectionID,
UpdateMask: &fieldmaskpb.FieldMask{
Paths: []string{message.FieldMaskCollectionSchema},
},
CacheExpirations: cacheExpirations,
}
body := &messagespb.AlterCollectionMessageBody{
Updates: &messagespb.AlterCollectionMessageUpdates{
Schema: schema,
},
}
addedFileResourceIds, err := c.prepareAlterCollectionAnalyzerFileResources(ctx, oldColl, schema)
if err != nil {
return err
}
channels := make([]string, 0, len(newColl.VirtualChannelNames)+1)
channels = append(channels, streaming.WAL().ControlChannel())
channels = append(channels, newColl.VirtualChannelNames...)
msg := message.NewAlterCollectionMessageBuilderV2().
WithHeader(header).
WithBody(body).
WithBroadcast(channels).
MustBuildBroadcast()
if _, err := broadcaster.Broadcast(ctx, msg); err != nil {
rollbackAlterCollectionAnalyzerFileResourceReservation(ctx, c.meta, newColl.CollectionID, addedFileResourceIds, err)
return err
}
return nil
}
// resolveFunctionFieldIDs re-derives the function's input/output field IDs from
// its field names (the source of truth), discarding any client-supplied IDs — else
// a request could inject an unrelated field ID that a later drop_function_field
// would delete. It rejects unknown fields and output fields already owned by
// another function, and marks the resolved output fields as function outputs.
func resolveFunctionFieldIDs(ctx context.Context, fSchema *schemapb.FunctionSchema, fieldMapping map[string]*model.Field) error {
fSchema.InputFieldIds = make([]int64, 0, len(fSchema.InputFieldNames))
for _, name := range fSchema.InputFieldNames {
field, exists := fieldMapping[name]
if !exists {
err := merr.WrapErrParameterInvalidMsg("function's input field %s not exists", name)
mlog.Error(ctx, "Incorrect function configuration:", mlog.Err(err))
return err
}
fSchema.InputFieldIds = append(fSchema.InputFieldIds, field.FieldID)
}
fSchema.OutputFieldIds = make([]int64, 0, len(fSchema.OutputFieldNames))
for _, name := range fSchema.OutputFieldNames {
field, exists := fieldMapping[name]
if !exists {
err := merr.WrapErrParameterInvalidMsg("function's output field %s not exists", name)
mlog.Error(ctx, "Incorrect function configuration:", mlog.Err(err))
return err
}
if field.IsFunctionOutput {
err := merr.WrapErrParameterInvalidMsg("function's output field %s is already of other functions", name)
mlog.Error(ctx, "Incorrect function configuration: ", mlog.Err(err))
return err
}
fSchema.OutputFieldIds = append(fSchema.OutputFieldIds, field.FieldID)
field.IsFunctionOutput = true
}
return nil
}
func alterFunctionGenNewCollection(ctx context.Context, fSchema *schemapb.FunctionSchema, collection *model.Collection) error {
if fSchema == nil {
return merr.WrapErrParameterInvalidMsg("function schema is empty")
}
var oldFuncSchema *model.Function
newFuncs := []*model.Function{}
for _, f := range collection.Functions {
if f.Name == fSchema.Name {
oldFuncSchema = f
} else {
newFuncs = append(newFuncs, f)
}
}
if oldFuncSchema == nil {
err := merr.WrapErrParameterInvalidMsg("function %s not exists", fSchema.Name)
mlog.Error(ctx, "Alter function failed:", mlog.Err(err))
return err
}
fSchema.Id = oldFuncSchema.ID
fieldMapping := map[string]*model.Field{}
for _, field := range collection.Fields {
fieldMapping[field.Name] = field
}
// reset output field info
for _, name := range oldFuncSchema.OutputFieldNames {
field, exists := fieldMapping[name]
if !exists {
return merr.WrapErrParameterInvalidMsg("old version function's output field %s not exists", name)
}
field.IsFunctionOutput = false
}
if err := resolveFunctionFieldIDs(ctx, fSchema, fieldMapping); err != nil {
return err
}
newFunc := model.UnmarshalFunctionModel(fSchema)
newFuncs = append(newFuncs, newFunc)
collection.Functions = newFuncs
return nil
}
func (c *Core) broadcastAlterCollectionForAlterFunction(ctx context.Context, req *milvuspb.AlterCollectionFunctionRequest) error {
broadcaster, err := c.startBroadcastWithAliasOrCollectionLock(ctx, req.GetDbName(), req.GetCollectionName())
if err != nil {
return err
}
defer broadcaster.Close()
oldColl, err := c.meta.GetCollectionByName(ctx, req.GetDbName(), req.GetCollectionName(), typeutil.MaxTimestamp, false)
if err != nil {
return err
}
if err := rejectExternalCollectionFunctionMutation(oldColl.ToCollectionSchemaPB()); err != nil {
return err
}
// Only whitelisted params may be altered; function identity (type, name,
// input/output fields) is immutable. Skip when the function is absent so the
// mutation helper below emits the canonical "not exists" error.
for _, fn := range oldColl.Functions {
if fn.Name == req.GetFunctionSchema().GetName() {
if err := validator.CheckFunctionAlterAllowed(model.MarshalFunctionModel(fn), req.GetFunctionSchema()); err != nil {
return err
}
break
}
}
newColl := oldColl.Clone()
if err := alterFunctionGenNewCollection(ctx, req.FunctionSchema, newColl); err != nil {
return err
}
return callAlterCollection(ctx, c, broadcaster, oldColl, newColl, req.GetDbName(), req.GetCollectionName())
}