Documentation
¶
Overview ¶
Package serverwiring is the process wiring the server binaries share: the --keyviz* and --autoSplit* flag groups and what they build, the metrics and pprof listeners, and the SigV4 static-credentials loader. Root main and the cmd/server demo both register and call it, so the demo cannot drift from the server binary.
Index ¶
- func ApplyLeadership(cfg *autosplit.SchedulerConfig, leader Leader)
- func BuildSampler(k *KeyVizFlags, a *AutoSplitFlags) *keyviz.MemSampler
- func LoadSigV4StaticCredentials(path string, label string) (map[string]string, error)
- func PrepareMetricsServer(ctx context.Context, lc *net.ListenConfig, addr, token string, ...) (*http.Server, net.Listener, string, error)
- func PreparePprofServer(ctx context.Context, lc *net.ListenConfig, addr, token string) (*http.Server, net.Listener, string, error)
- func SeedRoutes(s *keyviz.MemSampler, engine *distribution.Engine)
- func StartFlusher(ctx context.Context, eg *errgroup.Group, s *keyviz.MemSampler)
- func StartScheduler(ctx context.Context, eg *errgroup.Group, catalog *distribution.CatalogStore, ...)
- type AutoSplitFlags
- type DistributionSplitter
- type KeyVizFlags
- type Leader
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func ApplyLeadership ¶
func ApplyLeadership(cfg *autosplit.SchedulerConfig, leader Leader)
ApplyLeadership gates the scheduler on leadership of the catalog key when leader can answer per key (falling back to IsLeader), and wires term-scoped catalog and group leadership when leader reports terms.
func BuildSampler ¶
func BuildSampler(k *KeyVizFlags, a *AutoSplitFlags) *keyviz.MemSampler
BuildSampler builds the in-memory KeyViz sampler, or returns nil when neither --keyvizEnabled nor --autoSplit is set. The coordinators and the admin server treat a nil sampler as "KeyViz disabled", so this is the one decision point.
func LoadSigV4StaticCredentials ¶
LoadSigV4StaticCredentials parses a credentials file into an access key → secret map for WithS3StaticCredentials or WithSQSStaticCredentials. An empty path returns a nil map so authorization stays disabled. An empty field or an access key listed twice is an error: a second entry would silently replace the first. label names the adapter in errors ("s3 credentials file ...").
func PrepareMetricsServer ¶
func PrepareMetricsServer(ctx context.Context, lc *net.ListenConfig, addr, token string, handler http.Handler) (*http.Server, net.Listener, string, error)
PrepareMetricsServer validates the metrics address and token and binds the listener. An empty address or a nil handler disables metrics and returns zero values. It returns the server, its listener and the trimmed address.
func PreparePprofServer ¶
func PreparePprofServer(ctx context.Context, lc *net.ListenConfig, addr, token string) (*http.Server, net.Listener, string, error)
PreparePprofServer is PrepareMetricsServer for the pprof endpoints. An empty address disables pprof.
func SeedRoutes ¶
func SeedRoutes(s *keyviz.MemSampler, engine *distribution.Engine)
SeedRoutes copies the engine's current route catalogue into the sampler so the first matrix snapshots have non-empty metadata. The auto-split reconciler keeps membership current after catalog changes.
func StartFlusher ¶
StartFlusher runs the sampler's flusher and hot-key aggregator in eg. The flusher harvests the in-progress step with a final Flush once ctx ends, so a graceful shutdown keeps the most recent partial column. Nothing starts when the sampler is disabled.
func StartScheduler ¶
func StartScheduler( ctx context.Context, eg *errgroup.Group, catalog *distribution.CatalogStore, distServer *adapter.DistributionServer, leader Leader, sampler *keyviz.MemSampler, cfg autosplit.SchedulerConfig, )
StartScheduler runs the auto-split scheduler in eg when cfg is enabled. Without a sampler there is nothing to evaluate, so it logs and returns.
Types ¶
type AutoSplitFlags ¶
type AutoSplitFlags struct {
Enabled *bool
EvalInterval *time.Duration
SplitCooldown *time.Duration
SplitTimeout *time.Duration
KillSwitchFile *string
DefaultBuckets *int
WriteWeight *float64
ReadWeight *float64
ThresholdOpsMin *float64
CandidateWindows *int
MaxRoutes *int
MaxSplitsPerCycle *int
TopKeyAbsoluteFloor *float64
}
AutoSplitFlags is the --autoSplit* flag group that configures automatic same-group hotspot splits on the catalog leader.
func RegisterAutoSplitFlags ¶
func RegisterAutoSplitFlags(fs *flag.FlagSet) *AutoSplitFlags
RegisterAutoSplitFlags registers the --autoSplit* flags on fs.
func (*AutoSplitFlags) SchedulerConfig ¶
func (a *AutoSplitFlags) SchedulerConfig(leader Leader, k *KeyVizFlags) (autosplit.SchedulerConfig, error)
SchedulerConfig builds the scheduler configuration the flags describe, wires leader into it when leader is non-nil, and validates it against the KeyViz flags the sampler is built from.
type DistributionSplitter ¶
type DistributionSplitter struct {
Server *adapter.DistributionServer
}
DistributionSplitter executes auto-split decisions through the local distribution server's SplitRange.
func (DistributionSplitter) SplitRange ¶
func (s DistributionSplitter) SplitRange(ctx context.Context, req autosplit.SplitRequest) (autosplit.SplitResult, error)
SplitRange implements autosplit.Splitter. Only same-group splits are supported.
type KeyVizFlags ¶
type KeyVizFlags struct {
Enabled *bool
Step *time.Duration
MaxTrackedRoutes *int
MaxMemberRoutesPerSlot *int
HistoryColumns *int
KeyBucketsPerRoute *int
LabelsEnabled *bool
// Hot-key drill-down (design 2026_05_28_implemented_keyviz_hot_key_topk).
// When enabled the sampler retains actual hot key bytes and exposes
// them through the admin /keyviz/hotkeys drill-down.
HotKeysEnabled *bool
HotKeysPerRoute *int
HotKeysSampleRate *int
HotKeysQueueSize *int
HotKeysMaxKeyLen *int
// contains filtered or unexported fields
}
KeyVizFlags is the --keyviz* flag group that configures the in-memory key visualizer sampler. The sampler is off unless --keyvizEnabled or --autoSplit is set; the other flags are no-ops while it is off.
func RegisterKeyVizFlags ¶
func RegisterKeyVizFlags(fs *flag.FlagSet) *KeyVizFlags
RegisterKeyVizFlags registers the --keyviz* sampler flags on fs.
func (*KeyVizFlags) RecordExplicit ¶
func (k *KeyVizFlags) RecordExplicit(fs *flag.FlagSet)
RecordExplicit notes which of these flags fs saw on the command line. Call it after fs.Parse: --autoSplit raises the per-route key buckets only when the operator did not choose them.
Source Files