Files
milvus/internal/coordinator/file_resource_observer.go
T
e2787d3981 enhance: standardize error handling on merr + Sys/Input classification (#50221)
issue: #47420

## What this PR does

Project-wide migration of raw `fmt.Errorf` / `errors.New` in function
bodies onto
the `merr` framework, plus the Sys-vs-Input error classification and the
machinery it drives (retriability, fine-grained metrics, segcore
unification),
plus the convention docs and a linter that keeps it from regressing.

Scope: storage, proxy, coordinators (root/data/query), query node, data
node,
`pkg/util` & `internal/util`, expression parser, message queue,
streaming, and
misc packages. Bare raw-error usages went from ~3000 to a ~340 allowlist
(package-level sentinels / build-tag / test sites).

---

## How to review this PR

It is large but the vast majority is mechanical. Changes fall into three
tiers;
spend review budget on Part 2 and Part 3.

### Part 1 — Mechanical standardization (low risk, verify by rule)

Each converted call follows one of a small fixed set of rules. To
review, check
that each site obeys the matching rule rather than reading every line:

| Pattern | Rule |
|---|---|
| `fmt.Errorf("...")` originating a new error | →
`merr.WrapErrXxxMsg("...")` with a code matching the failure's meaning |
| Adding context to an existing typed error | → `merr.Wrap(err, "...")`
/ `merr.Wrapf(...)` — **preserves** the inner code (never `WrapErr*Err`,
which overwrites it) |
| Errors inside the streaming subsystem | → `status.New*` factories
(StreamingError), **not** merr — this is the component-internal dialect
(see `docs/dev/error_handling_guide.md`) |
| Low-level / control-flow signal caught by `errors.Is` | → kept as a
package-level `errors.New` sentinel (lowercase, same-package) |

Conventions are documented in `docs/dev/error_handling_guide.md`
(how-to) and
`docs/dev/error_sentinel_convention.md` (rules + audit). A
`gocritic`/`ruleguard`
rule (`rawmerrerror`, in `rules.go`) enforces "no raw `return
errors.New/fmt.Errorf`"
under `make verifiers`.

### Part 2 — Behavior changes (review these closely)

These are the sites where the wire contract or runtime behavior changes,
not just
the source text. Listed by category; representative locations given,
full set in
the diff.

**A. gRPC wire-code shifts: `UnexpectedError(1)/Code 65535` → typed
code.**
Where a handler previously returned a raw error (collapsed to
`Code=65535` on the
wire), it now returns a typed merr, so the client sees a real code. The
most
common shift is to `IllegalArgument(5)/Code 1100` (ParameterInvalid).
Touch
points include datanode task handlers (CreateTask/Query/Drop), proxy
Upsert,
querynode GetMetrics, datacoord CreateIndex, httpserver query-response
builder,
and typeutil schema validation. One code refinement: an index-param
validation
moved `1100` → `1101` (ParameterMissing). **Client/SDK assertions and
any code
that switched on `Code=65535` for these paths must be re-checked** (the
go_client
e2e assertions were already aligned in this PR).

**B. Prometheus `status` label contract change (externally visible).**
The proxy metric's coarse `fail` / `rejected` values are split into
`fail_input` / `fail_system` and `rejected_user` / `rejected_system` (in
`requestutil.ParseMetricLabel`; auth/privilege rejections count as
`rejected_user`), so dashboards can attribute a failure to caller vs
operator.
**Dashboards/alerts querying `status="fail"` must migrate to
`status=~"fail_.*"`, and `status="rejected"` to
`status=~"rejected_.*"`.** The
in-repo Grafana dashboard is already migrated; external dashboards built
on the
old values silently go empty after upgrade. This is the one change that
requires an ops-side migration.

**C. Retriability semantics.**
- C1: `merr.Status(err)` now forces `Retriable=false` when the error is
an
`InputError` — a malformed request can never succeed on blind retry, so
clients
never get the self-contradictory "your input is wrong but you may
retry".
- C2: `retry.Do` short-circuits an `InputError` (non-retriable) — **but
only when
  the caller did not pass a `RetryErr` predicate**. The check is an
`if c.isRetryErr != nil { ... } else if InputError { ... }` *mutually
exclusive*
branch (`pkg/util/retry/retry.go`): an explicit `RetryErr` takes
precedence and
bypasses the InputError abort. `retry.Handle` deliberately does **not**
apply
the InputError abort (its callers signal abort via `shouldRetry=false`).
Four
flusher startup callsites that must retry through transient "not ready"
errors
  were given explicit `RetryErr` escape hatches.

**D. segcore (C++→Go) error classification.**
A single shared Go-side table (`pkg/util/merr/segcore.go`) maps each
segcore code
to a merr sentinel + InputError/signal category, replacing scattered
hand-written
`if errorCode == ...` switches in the cgo wrappers. **Wire `Code` values
change
for every segcore pass-through error, not just the remapped ones.**
Named
sentinels remap (C++ `2003` → merr `2001`, `2033` → `2002`,
Folly/Knowhere codes
likewise); **all remaining pass-through codes (`2004`–`2043`, previously
surfaced to clients as raw C++ enum values) now serialize as `2000`**
(`ErrSegcore`), with the original C++ code preserved in the `Reason`
text
(`segcoreCode=...`); unknown/future codes collapse to `2000` as well
(pinned by
the `wire_code_projection` test). Transient segcore classes (object
storage /
file IO / OOM / mmap / FieldNotLoaded — 11 codes) now report
`Retriable=true`.
**Any client switching on raw segcore codes in the `2004`–`2043` range
must be
re-checked**; the in-Reason code remains available for diagnostics.
Signal
codes (PretendFinished / FollyCancel) are recognized centrally.
`errors.Is`-based
control flow on these (e.g. scheduler skip/retry) is preserved.

**E. InputError classification (25 sentinels + dynamic marks).**
25 sentinels in `errors.go` carry `WithErrorType(InputError)` (the
Collection /
ResourceGroup / Database families, `ErrIndexDuplicate`,
`ErrParameterInvalid`,
`ErrPrivilegeNotAuthenticated`, `ErrImportFailed`, `ErrQueryPlan`, ...),
plus dynamic
marks for the 8 segcore input codes (ExprInvalid, DimNotMatch,
MetricTypeInvalid, FieldIDInvalid, ...) and
`WrapErrAsInputError`. The widest blast radius is `ErrParameterInvalid`
(1100):
~2335 `WrapErrParameterInvalid*` callsites now classify as input /
non-retriable. Because of C1/C2 this changes retriability for
any path that returns these. **The audit to confirm no transient path
was
mis-marked is the single most important review item** (see Part 3). One
reverse
correction: storage field-stats parsing moved from `ErrParameterInvalid`
(input)
to `ErrDataIntegrity` — a corrupted stored stat is data corruption, not
user
input.

### Part 3 — Known risks & traps (called out proactively)

1. **`merr.Wrap` vs `WrapErr*Err` (code-masking).** `WrapErr*Err` builds
a
`wrappedMilvusError{sentinel: ErrServiceInternal}` whose `code()`
returns the
*outer* sentinel — it overwrites the inner typed code and hides the
`errors.Is`
chain. This is intentional (use it to *deliberately* downgrade), but it
was a
recurring conversion defect; the rule "add context with `merr.Wrap`,
downgrade
with `WrapErr*Err`" is enforced by convention and reviewed across the
diff.
2. **InputError × `retry.Do` blast radius.** Marking a sentinel
`InputError` makes
any `retry.Do(...)` without a `RetryErr` predicate stop retrying it.
Reviewers
should sanity-check that no transient use of the 19 newly-marked
sentinels
(especially `ErrParameterInvalid`) sits inside a retry loop that needed
to keep
   spinning. The known flusher cases were handled (see C2).
3. **The ~340 raw-error allowlist.** What remains as bare `errors.New`
is, by
design: package-level sentinels (caught by `errors.Is`), `//go:build
test`
sites, and out-of-band trees (`cmd/`, `tests/`, codegen, walimpls). The
linter
only bans the *direct-return* form; assignment-then-return escapes and
the full
no-exceptions ban are deferred to an AST-based linter (Tier 2,
documented).
4. **segcore C++ second step deferred.** This PR unifies classification
on the Go
side; splitting the dual-semantic C++ codes at the source is a
follow-up.

---

## Validation

- `make verifiers`: Go side clean (gofmt + static-check across modules,
including
  the new `rawmerrerror` rule with a 0-hit baseline repo-wide).
- `make test-go`: passing; the one real regression introduced (a
datanode
`invalid_task_type` assertion shifting `1` → `5` from a ParameterInvalid
  conversion) was fixed in-tree.
- go_client e2e CreateIndex assertions aligned to the new merr messages.

---------

Signed-off-by: zhenshan.cao <zhenshan.cao@zilliz.com>
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-06-12 15:04:51 -07:00

296 lines
7.7 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 coordinator
import (
"context"
"sync"
"time"
"github.com/samber/lo"
"go.uber.org/zap"
dcsession "github.com/milvus-io/milvus/internal/datacoord/session"
qcsession "github.com/milvus-io/milvus/internal/querycoordv2/session"
"github.com/milvus-io/milvus/internal/rootcoord"
"github.com/milvus-io/milvus/internal/util/fileresource"
"github.com/milvus-io/milvus/pkg/v3/log"
"github.com/milvus-io/milvus/pkg/v3/proto/internalpb"
"github.com/milvus-io/milvus/pkg/v3/util/conc"
"github.com/milvus-io/milvus/pkg/v3/util/merr"
"github.com/milvus-io/milvus/pkg/v3/util/paramtable"
"github.com/milvus-io/milvus/pkg/v3/util/typeutil"
)
type NodeType int
const (
QueryNode NodeType = 0 + iota
DataNode
)
type NodeInfo struct {
NodeID int64
NodeType NodeType
Version uint64
}
type FileResourceMeta interface {
GetResources() ([]*internalpb.FileResourceInfo, uint64)
}
type FileResourceObserver struct {
ctx context.Context
meta rootcoord.IMetaTable
syncMu sync.Mutex
distribution *typeutil.ConcurrentMap[int64, *NodeInfo]
// node manager
qnManager *qcsession.NodeManager
dnManager dcsession.NodeManager
cluster qcsession.Cluster
// mode
qnMode fileresource.Mode // tips: streaming node used as query node now
dnMode fileresource.Mode
notifyCh chan struct{}
closeCh chan struct{}
wg sync.WaitGroup
sf conc.Singleflight[any]
startonce sync.Once
closeOnce sync.Once
}
func NewFileResourceObserver(ctx context.Context) *FileResourceObserver {
return &FileResourceObserver{
ctx: ctx,
distribution: typeutil.NewConcurrentMap[int64, *NodeInfo](),
notifyCh: make(chan struct{}, 1),
closeCh: make(chan struct{}),
sf: conc.Singleflight[any]{},
dnMode: fileresource.ParseMode(paramtable.Get().CommonCfg.DNFileResourceMode.GetValue()),
qnMode: fileresource.ParseMode(paramtable.Get().CommonCfg.QNFileResourceMode.GetValue()),
}
}
// sleep and notify to sync
func (m *FileResourceObserver) RetryNotify() {
go func() {
m.sf.Do("retry", func() (any, error) {
time.Sleep(3 * time.Second)
m.Notify()
return nil, nil
})
}()
}
func (m *FileResourceObserver) syncLoop() {
defer m.wg.Done()
for {
select {
case <-m.notifyCh:
err := m.Sync()
if err != nil {
// retry if error exist
m.RetryNotify()
}
case <-m.closeCh:
log.Info("file resource observer close")
return
case <-m.ctx.Done():
log.Info("file resource observer context done")
return
}
}
}
func (m *FileResourceObserver) Start() {
if m.qnMode == fileresource.SyncMode || m.dnMode == fileresource.SyncMode {
m.startonce.Do(func() {
m.wg.Add(1)
go m.syncLoop()
m.Notify()
})
}
}
func (m *FileResourceObserver) Stop() {
m.closeOnce.Do(func() {
close(m.closeCh)
m.wg.Wait()
})
}
func (m *FileResourceObserver) Notify() {
select {
case m.notifyCh <- struct{}{}:
default:
}
}
// if node sync at least once, it will be a valid node.
func (m *FileResourceObserver) CheckNodeSynced(nodeID int64) bool {
// return false if meta is not ready
if m.meta == nil {
return false
}
resources, version := m.meta.ListFileResource(m.ctx)
// skip check if no any resource
if version == 0 || len(resources) == 0 {
return true
}
_, ok := m.distribution.Get(nodeID)
return ok
}
// check if all valid nodes sync the resource to current version
func (m *FileResourceObserver) CheckAllQnReady() error {
// return error if meta is not ready
if m.meta == nil {
return merr.WrapErrServiceUnavailable("rootcoord meta is not ready")
}
resources, version := m.meta.ListFileResource(m.ctx)
// skip check if no any resource
if version == 0 || len(resources) == 0 {
return nil
}
var err error
m.distribution.Range(func(nodeID int64, node *NodeInfo) bool {
if node.NodeType == QueryNode && node.Version < version {
err = merr.WrapErrServiceUnavailableMsg("file resource not synced, node-%d", nodeID)
return false
}
return true
})
return err
}
func (m *FileResourceObserver) Sync() error {
m.syncMu.Lock()
defer m.syncMu.Unlock()
var syncErr error
nodeIDs := []int64{}
resources, targetVersion := m.meta.ListFileResource(m.ctx)
// sync file resource to query node if file resource mode was Sync
if m.qnMode == fileresource.SyncMode {
qnnodes := m.qnManager.GetAll()
for _, node := range qnnodes {
if info, ok := m.distribution.Get(node.ID()); !ok || info.Version < targetVersion {
status, err := m.cluster.SyncFileResource(m.ctx, node.ID(), &internalpb.SyncFileResourceRequest{
Resources: resources,
Version: targetVersion,
})
if err != nil {
log.Warn("sync file resource failed", zap.Int64("nodeID", node.ID()), zap.Error(err))
syncErr = err
continue
}
if err = merr.Error(status); err != nil {
log.Warn("sync file resource failed", zap.Int64("nodeID", node.ID()), zap.Error(err))
syncErr = err
continue
}
m.distribution.Insert(node.ID(), &NodeInfo{
NodeID: node.ID(),
NodeType: QueryNode,
Version: targetVersion,
})
log.Info("finish sync file resource to query node", zap.Int64("node", node.ID()), zap.Uint64("version", targetVersion))
}
}
for _, node := range qnnodes {
nodeIDs = append(nodeIDs, node.ID())
}
}
// sync file resource to data node if file resource mode was Sync
if m.dnMode == fileresource.SyncMode {
dnnodes := m.dnManager.GetClientIDs()
for _, nodeID := range dnnodes {
if info, ok := m.distribution.Get(nodeID); !ok || info.Version < targetVersion {
c, err := m.dnManager.GetClient(nodeID)
if err != nil {
log.Warn("sync file resource failed, fetch client failed", zap.Error(err))
syncErr = err
continue
}
status, err := c.SyncFileResource(m.ctx, &internalpb.SyncFileResourceRequest{
Resources: resources,
Version: targetVersion,
})
if err != nil {
syncErr = err
log.Warn("sync file resource failed", zap.Int64("nodeID", nodeID), zap.Error(err))
continue
}
if err = merr.Error(status); err != nil {
log.Warn("sync file resource failed", zap.Int64("nodeID", nodeID), zap.Error(err))
syncErr = err
continue
}
m.distribution.Insert(nodeID, &NodeInfo{
NodeID: nodeID,
NodeType: DataNode,
Version: targetVersion,
})
log.Info("finish sync file resource to data node", zap.Int64("nodeID", nodeID), zap.Uint64("version", targetVersion))
}
}
nodeIDs = append(nodeIDs, dnnodes...)
}
// delete node from distribution if node is not in manager
m.distribution.Range(func(nodeID int64, node *NodeInfo) bool {
if !lo.Contains(nodeIDs, nodeID) {
m.distribution.Remove(nodeID)
}
return true
})
if syncErr != nil {
return syncErr
}
return nil
}
func (m *FileResourceObserver) InitMeta(meta rootcoord.IMetaTable) {
m.meta = meta
}
func (m *FileResourceObserver) InitQueryCoord(manager *qcsession.NodeManager, cluster qcsession.Cluster) {
m.qnManager = manager
m.cluster = cluster
}
func (m *FileResourceObserver) InitDataCoord(manager dcsession.NodeManager) {
m.dnManager = manager
}