fix(opampextension): skip no-op RemoteConfig + advertise ReportsRemoteConfig (ASAPCollector#381 Issue #4) - #389
Merged
Conversation
…eConfig (ASAPCollector#381 Issue #4) Two paired fixes to close the apply-loop the smoke test surfaced after ASAPQuery-backend PR #279 landed: (1) No-op short-circuit in processRemoteConfig Before writing the pushed body to disk + exiting, compare to the current on-disk file. If they match byte-for-byte, just report APPLIED and return — don't restart. This handles two scenarios: * Defense-in-depth against a controller resending the same config (which can happen any time the OpAMP server's LastRemoteConfigHash cache is empty or stale — e.g. on reconnect before the agent has reported APPLIED). * The deterministic-emit guarantee from ASAPQuery-backend #281 means same-semantic-content → same bytes, so this check is accurate for the controller's emit. (2) Advertise ReportsRemoteConfig capability In addition to AcceptsRemoteConfig, set `AgentCapabilities_AgentCapabilities_ReportsRemoteConfig` when `remote_config_path` is configured. Without this bit, `opampClient.SetRemoteConfigStatus(APPLIED)` returns `ErrReportsRemoteConfigNotSet` (opamp-go client/internal/clientcommon.go:21), the client lib refuses to record the applied hash, and the server has no way to learn the config was processed — keeping it stuck in the resend loop. Both bits are needed for the full feedback cycle. End-to-end smoke (post-#281 deterministic emit + this PR): * Agent boots from bootstrap YAML * Receives RemoteConfig push, bytes differ, applies + exits * Restarts, loads new YAML * Receives RemoteConfig push, bytes IDENTICAL (deterministic emit) * No-op short-circuit fires → SetRemoteConfigStatus(APPLIED) → keeps running, no more restarts * Pipeline emits sketches normally; smoke test Axis D registers them Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
4 tasks
zzylol
added a commit
that referenced
this pull request
May 18, 2026
…locks (#391) PR #383 (and #389 follow-up) added the `RemoteConfigPath` field to the patched opampextension: when set, the extension applies pushed AgentRemoteConfig by writing the YAML to disk and exiting, so a restart-policy-enabled supervisor (Docker `restart: unless-stopped`, systemd, k8s) brings the agent back up with the new config. The mvp-smoke-test agent uses this field via its overlay-mounted `agent.yaml`, but the 13 stock agent yamls in `deploy/mvp-singlenode/configs/asap-otel-agent-*.yaml` still ship without it, so OpAMP-apply silently no-ops in stock single-node deploys (the controller's push is received, the extension reports back, but nothing is persisted across the implied restart — the next boot reloads the same static bootstrap yaml). This change adds `remote_config_path: /etc/otel/config.yaml` (the same path the collector boots from via `--config=/etc/otel/config.yaml`, and the same convention the smoke-test uses) to the `extensions.opamp:` block of every stock yaml that already declares one. Files touched (13): - asap-otel-agent-allsketches.yaml - asap-otel-agent-b0-prometheus.yaml - asap-otel-agent-b0-victoriametrics.yaml - asap-otel-agent-b1-serf-prometheus.yaml - asap-otel-agent-b3-delta-direct.yaml - asap-otel-agent-b5-gorilla-prometheus.yaml - asap-otel-agent-b5-gorilla-victoriametrics.yaml - asap-otel-agent-b6-asap-single-sketch.yaml - asap-otel-agent-b6-gorilla-s3.yaml - asap-otel-agent-cms-direct.yaml - asap-otel-agent-cs-direct.yaml - asap-otel-agent-hll-direct.yaml - asap-otel-agent-kll-direct.yaml The 6 stock yamls WITHOUT an `extensions.opamp:` block (`b0a-raw-stream`, `b0b-raw-batched`, `b2-full`, `b3-delta`, `b4-tunable`, `kafka-fragment`) are intentionally left alone — adding `remote_config_path` would require also wiring up `extensions:` + `service.extensions:`, which is out of scope for this sweep. OPERATIONAL CAVEAT (flagged inline + in each yaml's comment): the stock `agents-N{1,10,100}.yml` compose overlays mount `/etc/otel/config.yaml` read-only (`:ro` suffix on the bind mount) and do NOT set a restart policy on the agent service. As-shipped, the extension's disk-write will fail with EROFS and the agent process will exit without coming back. To actually exercise OpAMP-apply persistence in a stock deploy, the operator must additionally: 1. Drop `:ro` from the agent's config volume mount (so the opampextension can write back to the same path the collector boots from), and 2. Add `restart: unless-stopped` (or equivalent) to the agent service so the container respawns after the extension exits. The smoke-test's `mvp-smoke-test/compose/smoke-overlay.yml` does both via `volumes: !override` + `restart: unless-stopped` — that is the reference pattern. The compose-side wiring update is deferred to a follow-up so this PR stays narrowly scoped to the agent yaml schema. YAML validity verified with `python3 -c "import yaml; ..."` over all 19 stock agent yamls; the 13 modified files parse with `extensions.opamp.remote_config_path == "/etc/otel/config.yaml"`. Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Summary
Closes the apply-loop the smoke test surfaced after ASAPQuery-backend #279 + #281 landed. Two fixes:
processRemoteConfig: compare incoming body to on-disk file before writing. If identical, just report APPLIED and return — no restart. Pairs with the deterministic emit from ASAPQuery-backend feat(asap-gorilla): Phase 1 block format encoder + decoder + index file #281 (same semantic content → same bytes, so byte comparison is accurate).ReportsRemoteConfigcapability alongsideAcceptsRemoteConfig. Without it,opampClient.SetRemoteConfigStatus(APPLIED)returnsErrReportsRemoteConfigNotSet— the client lib won't record the applied hash, server keeps resending.Smoke flow post-fix
🤖 Generated with Claude Code