Extends the heartbeat mechanism with a second gRPC service on the same mTLS channel (AgentControl.CheckIn, agent-initiated on the existing heartbeat ticker -- still push-only, no inbound port on any agent) so an agent reports its running config and can pick up an operator-set override. A new web UI section (/agents) lists every agent that's checked in, shows its reported config, and lets an operator edit a narrow, deliberately-scoped subset remotely: batch/heartbeat tuning, and (journald sources only) the unit filter. TLS material and the ingest endpoint are never reportable or remotely editable, by proto shape rather than a validation rule -- a bad or malicious edit there could permanently strand an agent or redirect where its logs go, unlike every other editable field, which only degrades behavior. An override lives only in the agent's memory (agent.toml is never rewritten) and re-syncs on the agent's own schedule; changing the journald filter aborts and respawns the source task since there's no other way to change what's being tailed. Building the hot-reload path surfaced a real, independent, pre-existing bug: shutdown was using poll_timeout(), which only drains once flush_interval has elapsed, silently dropping anything buffered more recently on every graceful shutdown that landed between flushes -- fixed with a new unconditional Batcher::flush_all(), now used at both shutdown and hot-reload. Verified live end-to-end against a real stack: an edited heartbeat interval changed a running agent's actual send cadence within one check-in cycle (confirmed by the real timestamps landing in ClickHouse), and an edited journald filter triggered a real source restart, both reflected back in the next reported-config snapshot. See /docs/agent-management-design.md.
ingest
Go service sitting between the Rust agent and ClickHouse. Two halves in one
binary, selected with --mode:
- server — mTLS gRPC front end (
LogIngest.PushBatch) that agents connect to. Assigns each record a server-siderecord_id(a UUID, overwriting whatever the agent sent — agents always send it empty) and otherwise forwards records proto-encoded onto Redpanda unchanged. Still kept thin — one field assignment, no real normalization — so agent- facing latency isn't coupled to ClickHouse write performance.record_idhas to be assigned exactly once, here, rather than independently by each downstream consumer: Phase 1's Tantivy indexer and the ClickHouse writer both read the same Redpanda messages and need to agree on the same ID for the same record to join search hits back to rows — two consumers generating their own IDs would produce mismatched ones for what's supposed to be the same record. Also (Phase 4): resolves an optional per-tenantAuthorization: Bearer <token>credential viainternal/grpcserver.TenantResolver(nil by default -- single-tenant behavior unchanged) and attaches the resolved tenant ID to every produced Kafka message as atenant_idheader (consumer.TenantIDHeaderKey) -- see "Multi-tenant write-routing" below. - consumer — reads back off Redpanda, normalizes into the ClickHouse row
shape (
internal/normalize), and batch-writes via the native protocol driver. Commits Redpanda offsets only after a successful ClickHouse write, so a ClickHouse outage causes redelivery on restart rather than data loss. Reads each message'stenant_idheader (if any) but this package's own writer (clickhousewriter.Writer, used bycmd/ingest's single-tenant mode) ignores it -- every record still lands in the one shared ClickHouse database regardless of tag. See "Multi-tenant write-routing" below for where the tag actually gets used. - all (default) — both, in one process. This is what docker-compose
runs. Splitting into two deployments later (e.g. to scale them
independently in k8s) is a manifest change, not a code change — see
--mode.
Multi-tenant write-routing
This package (AGPL core) only ever writes to one shared ClickHouse
database, regardless of any tenant_id tag a message carries -- routing
a tagged record into its own tenant's dedicated database is
enterprise/internal/chwriter and enterprise/cmd/enterprise-ingest's
job (a separate module by architectural convention, not a licensing
split -- both are AGPLv3, see /CLAUDE.md's licensing boundary), not
this package's. consumer and clickhousewriter live outside
internal/ (moved there once enterprise/internal/chwriter needed to
import them directly -- Go's compiler-enforced internal/ visibility
rule blocks a separate module from importing anything under
ingest/internal/..., the same reason several api/internal/...
packages moved out earlier in Phase 4) specifically so enterprise/ can
reuse this package's own flush loop and ClickHouse batch-insert logic
unchanged, rather than reimplementing either. See
/enterprise/README.md's "Ingest tenant identity"/write-routing
sections for the full story, including what's still not built.
Why Redpanda stays in the path
Confirmed with the project owner during Phase 0 planning: the gRPC front
end produces to Redpanda rather than writing ClickHouse directly. This
exercises the pinned transport layer from day one and keeps agents from
ever needing Kafka credentials — mTLS to ingest is the only network
egress an agent has. See /docs/architecture.md.
Dependencies worth knowing about
- github.com/segmentio/kafka-go — pure Go, no cgo, chosen over franz-go/confluent-kafka-go specifically to keep the distroless build simple (confirmed with the project owner; see git history / PR discussion for the tradeoffs considered).
- github.com/ClickHouse/clickhouse-go/v2 — official client, native protocol, pure Go (no cgo).
- golang.org/x/sync/errgroup — used in
cmd/ingest/main.goto run the server and consumer halves concurrently and propagate the first error. - github.com/google/uuid — was already in the dependency graph
transitively (via clickhouse-go); promoted to a direct dependency for
record_idgeneration ininternal/grpcserver, so not a new addition to the transitive tree.
Configuration
All via environment variables (see internal/config/config.go for the
full list and defaults) — no config file format for Phase 0:
| Var | Default | Purpose |
|---|---|---|
GRPC_LISTEN_ADDR |
:4317 |
Agent-facing gRPC listen address |
TLS_CERT_FILE / TLS_KEY_FILE |
/etc/sentry-ingest/server{,-key}.pem |
ingest's own mTLS identity |
TLS_CLIENT_CA_FILE |
/etc/sentry-ingest/ca.pem |
CA used to verify agent client certs |
REDPANDA_BROKERS |
localhost:9092 |
Comma-separated broker list |
REDPANDA_TOPIC |
sentry.logs.raw |
Must match the topic provisioned in /transport |
REDPANDA_CONSUMER_GROUP |
sentry-ingest |
Consumer group id |
CLICKHOUSE_ADDR |
localhost:9000 |
Native protocol port, not HTTP |
CLICKHOUSE_DATABASE / _USERNAME / _PASSWORD |
sentry / default / `` |
|
CONSUMER_BATCH_MAX_SIZE |
500 |
Records per ClickHouse batch insert |
CONSUMER_BATCH_FLUSH_INTERVAL_MS |
2000 |
Max time a partial batch waits before flushing |
ENTERPRISE_AUTH_URL |
(empty) | Enables internal/grpcserver.TenantResolver -- empty means PushBatch never requires a bearer credential and no tenant_id header is ever attached, same as every Phase 0-3 deployment |
Building & testing
go build ./...
go vet ./...
go test ./...
Requires google.golang.org/protobuf/cmd/protoc-gen-go and
google.golang.org/grpc/cmd/protoc-gen-go-grpc only if you're
regenerating /proto's Go bindings — ingest itself just imports the
already-generated github.com/sentry/sentry/proto module (see the
replace directive in go.mod, pointing at ../proto).
# from the repo root, not ingest/
docker build -f ingest/Dockerfile -t sentry-ingest .
Testing notes
consumer and internal/grpcserver depend on Redpanda and ClickHouse
only through small interfaces (reader/chWriter in consumer,
batchProducer in grpcserver), so the flush/commit/error-handling logic is
unit-tested against fakes — no embedded broker or database needed. This
includes the tenant_id tagging/extraction round trip end to end (a fake
TenantResolver in grpcserver's tests, a fake Kafka header in
consumer's) — real logic, fake transport, no live enterprise-auth or
Redpanda needed. What's not covered by these tests: the real
kafka.Reader/kafka.Writer wiring and the ClickHouse native-protocol
driver itself. Those are only exercised by the docker-compose end-to-end
flow described in /docs/phase-0-runbook.md.