#955 YAML simplification and restart service when configuration changes Pull request opened by javuto Summary Adds an "Apply & Restart" button that triggers a graceful service restart so DB-edited config changes take effect, and makes the YAML file optional for non-connection sections. Problem Two gaps remained: 1. Changes didn't propagate. An operator could edit a config section in the frontend and save it to the DB, but the running service kept using the in-memory config loaded at boot. The change only took effect on the next manual restart. The "Saved ✓" feedback was misleading — it meant "persisted to DB," not "active." 2. YAML couldn't be simplified. Every config section had to be present in the YAML file, even sections the operator intended to manage from the database. Missing sections became zero-valued structs, indistinguishable from intentionally-zero values. Changes Optional YAML (

pkg/config/types.go

,

cmd/tls/utils.go

,

cmd/api/utils.go

) Changed

TLSConfiguration

and

APIConfiguration

so that required sections (

service

,

db

,

redis

) remain value types, while all optional sections (

osquery

,

tls

,

logger

,

carver

,

debug

,

batchWriter

,

configEndpoints

,

osctrld

,

metrics

,

saml

,

oidc

,

jwt

) are now pointer types. When the YAML omits a section, the pointer stays nil instead of pointing to a zero-valued struct.

loadedYAMLToServiceParams

only sets pointers for sections the YAML actually provides. Existing deployments with full YAML files are unaffected — all sections are present, pointers are non-nil, behavior is identical. Nil-safe Resolve (

pkg/serviceconfig/serviceconfig.go

)

applySection

now returns

(bool, error)

and checks each

ServiceParameters

field for nil before unmarshaling. When a DB row with

source=db

exists for a section that the minimal YAML didn't provide (nil pointer), the value is skipped safely instead of panicking. Apply & Restart endpoint (

cmd/api/handlers/service_config.go

)

POST /api/v1/service-config/apply

— `ServiceConfigApplyHandler`: • Requires

AdminLevel

+

NoEnvironment

permissions. • Audit-logs the action via

AuditLog.SettingsAction

. • Returns 202 immediately; signals a restart channel asynchronously so the HTTP response completes before shutdown begins. • Returns 503 if

RestartCh

is not wired. Graceful shutdown (

cmd/api/main.go

) • Added a

restartCh chan struct{}

wired to the handlers via

WithRestartCh

. • Restructured the HTTP server start from blocking

http.ListenAndServe

to

http.Server

running in a goroutine, with the main goroutine selecting on either a server error or the restart signal. • On restart signal: calls

srv.Shutdown()

with a 10-second timeout, then

os.Exit(0)

. The process manager (systemd, docker, k8s) restarts the service, and

Resolve

applies all

source=db

sections on boot. • Added nil-safe

TLS

pointer check for the optional-YAML case. Frontend (

frontend/src/features/service-config/ServiceConfigPage.tsx

) • "Apply & Restart" button appears in the toolbar when any section has

source=db

(pending DB-edited changes that need a restart). • Button shows "Restarting…" while the POST is in flight, then "Restart triggered ✓" on success. •

applyServiceConfig()

API client function added to

frontend/src/api/service-config.ts

. Tests • Backend:

TestSeed_NilOptionalSections_DoesNotPanic

,

TestResolve_NilOptionalSection_DBValueIgnored

— verify nil section pointers don't crash Seed/Resolve. • Frontend: 3 new tests — no Apply button when no

source=db

sections, Apply button appears when

source=db

exists, clicking Apply calls

applyServiceConfig

. Validation •

go build ./...

— clean •

go test ./...

— all packages pass •

npm run check

— TypeScript typecheck clean •

npm test

— 34 test files / 206 tests pass •

golangci-lint

— 0 issues on modified files How it works end-to-end 1. Operator edits

debug

section in the frontend → PUT saves it to DB with

source=db

. 2. "Apply & Restart" button appears in the toolbar. 3. Operator clicks it →

POST /api/v1/service-config/apply

→ 202 Accepted →

restartCh

signalled. 4. Main goroutine receives signal →

srv.Shutdown()

→

os.Exit(0)

. 5. Process manager restarts the service →

Seed

(doesn't clobber

source=db

) →

Resolve

applies the DB value to

ServiceParameters

. 6. Service runs with the edited config. Deployment impact Existing deployments: unchanged. Full YAML files work as before. New deployments: can ship a minimal YAML with only

service

,

db

, and

redis

. Optional sections are managed from the database via the API. On first boot, only required sections are seeded. The operator configures the rest through the frontend and clicks "Apply & Restart" when ready. Breaking change:

TLSConfiguration

and

APIConfiguration

struct field types changed from values to pointers for optional sections. Internal to the repo; no external consumers known. jmpsec/osctrl