Configuration
How the KubeMQ GCP Pub/Sub connector is enabled, secured, and configured — a server-side, opt-in gRPC emulator.
The Pub/Sub connector is configured server-side under the Connectors.Gcp block of the KubeMQ
server config, exposed as thirteen CONNECTORS_GCP_* environment variables. The connector
is opt-in (disabled by default) — a stock kubemq-server does not bind gRPC port 8085 until
you enable it.
The only thing clients configure is the emulator host via the standard
PUBSUB_EMULATOR_HOST environment variable (default localhost:8085) plus any
PUBSUB_PROJECT_ID. Everything below is broker-side server configuration.
Enable the connector
Enable the connector with its enable variable:
docker run -d \ --name kubemq \ -p 8085:8085 \ -p 50000:50000 \ -e KUBEMQ_TOKEN=YOUR_LICENSE_KEY \ -e CONNECTORS_GCP_ENABLE=true \ europe-docker.pkg.dev/kubemq/images/kubemq:nextTo turn it off again, set CONNECTORS_GCP_ENABLE=false.
Setting CONNECTORS_GCP_ENABLE=false closes port 8085 and skips the connector entirely — a
config-only rollback with no data migration. The enable variable carries the underscore in its
prefix (CONNECTORS_GCP_*), and the port must differ from the server's gRPC/REST/HTTP and
AWS-connector ports — a collision aborts startup.
Security posture
The connector runs in emulator mode: no authentication, no TLS, insecure gRPC — by design.
There is no Google OAuth2/JWT validation, no IAM enforcement (the IAM RPCs are permissive
stubs), and no per-connector TLS option. Do not expose port 8085 to untrusted networks. TLS
is provided by the server-wide Security block, not by a Pub/Sub-specific setting. DoS guards
stay active regardless — the message-size cap, MaxInflightPerSubscription,
MaxConcurrentPolls, MaxSeekReplay, and push backoff. See
Auth & security and
Connectivity & emulator mode.
Configuring the connector
The same settings can be supplied through a TOML config file, environment variables, or
docker run flags. Every environment variable uses the CONNECTORS_GCP_ prefix (with the
underscore between CONNECTORS and GCP). For the full field-by-field table and copy-paste
TOML/env/Docker examples, see
Configuration reference.
Related
Getting Started
Point your Pub/Sub SDK at port 8085 and run a publish-and-pull round-trip end-to-end in minutes.
Architecture
The gRPC emulator listener, the 38-RPC surface, and the publish-once-then-fan-out model.
Connectivity & emulator mode
The PUBSUB_EMULATOR_HOST drop-in, per-language emulator opt-in, and the insecure-gRPC posture.
Configuration reference
The thirteen CONNECTORS_GCP_* fields, their defaults, and TOML/env/Docker examples.
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Architecture
Inside the KubeMQ Pub/Sub connector — the gRPC emulator listener, the 38-RPC surface, and how topics and subscriptions map to Events Store logs and Queues.
Cross-Protocol Interop
Publish with a Google Pub/Sub SDK and consume natively with a KubeMQ client on the Events Store log gcp.{topic}, carrying the reserved _pubsub_* tags across.