Skip to main content

Configure the Temporal Proxy

View Markdown

The proxy reads a single YAML file. Three sections are the core of it: the gateway listener (hostPort), routing, and the upstreams it forwards to. The optional allowedServices, tls, auth, encryption, and extensionServers sections narrow which gRPC services the proxy forwards and add inbound TLS, inbound authentication and authorization, and payload encryption. Values support ${VAR} and $VAR environment variable expansion, and an upstream's hostPort can be a template that resolves per request (for example, {{ .RemoteNamespace }}).

The example below is the proxy's Temporal Cloud example, which connects a Worker to Temporal Cloud with an API key. The Worker carries no Cloud configuration: it talks plaintext to 127.0.0.1:7233, and the proxy adds TLS, the API key, and the Namespace rewrite on the way out.

# Gateway: the local endpoint your Workers and Clients connect to (plaintext).
hostPort: 127.0.0.1:7233

routing:
default: cloud # Namespaced requests.
system: system # Namespace-less requests (for example GetSystemInfo on connect).

upstreams:
# Namespaced traffic. The host is derived per request from the translated
# Namespace, so one entry serves any number of Namespaces.
- name: cloud
hostPort: '{{ .RemoteNamespace }}.tmprl.cloud:7233'
tls: {} # Enable outbound TLS with defaults.
namespaces:
rules:
suffix: .$TEMPORAL_ACCOUNT # quickstart becomes quickstart.<account>
credentials:
static:
apiKey: $TEMPORAL_API_KEY

# Namespace-less calls have no Namespace to derive a host from, so they use a
# fixed endpoint. Any Namespace endpoint in the account answers them.
- name: system
hostPort: ${TEMPORAL_NAMESPACE}.${TEMPORAL_ACCOUNT}.tmprl.cloud:7233
tls: {}
credentials:
static:
apiKey: ${TEMPORAL_API_KEY}

The chart values.yaml and the temporal-proxy repository hold the complete, current set of options.

Restrict forwarded services

The top-level allowedServices list names the gRPC services the proxy forwards, by proto full name. Omit it and the proxy forwards WorkflowService and OperatorService, which is what an SDK Client, a Worker, the CLI, and the Web UI need.

allowedServices:
- temporal.api.workflowservice.v1.WorkflowService
- temporal.api.operatorservice.v1.OperatorService
- grpc.reflection.v1.ServerReflection
ServiceBacksIn the default set
temporal.api.workflowservice.v1.WorkflowServiceEvery SDK Client, Worker, and the Web UIYes
temporal.api.operatorservice.v1.OperatorServicetemporal operator commands, and the Web UI's Search Attribute and Nexus viewsYes
grpc.reflection.v1.ServerReflectionService discovery for tools such as grpcurlNo

Those three are the whole set to select from. A name the proxy cannot forward fails the configuration at startup rather than at the first request.

A service you leave out is never forwarded. The gateway answers a call to one with Unimplemented and unknown service "<name>", decided before any upstream work, so the proxy behaves as a server that does not implement it rather than passing the call through.

Service discovery is opt-in, so name the reflection service only when you want tools such as grpcurl to probe the gateway. Allowing grpc.reflection.v1.ServerReflection also allows the superseded grpc.reflection.v1alpha.ServerReflection, because clients probe v1 and fall back to it. The relation runs one way: allowing only the superseded spelling does not allow the current one.

Health checks

The gateway serves the standard gRPC health service and publishes an entry for every allowed service under its proto full name, alongside the usual empty service name. Each entry reports the same status, since the proxy's health is process-wide. A Client health check that names a service, such as the Go SDK's CheckHealth, therefore gets a status, and so does a per-service liveness probe. A service your configuration does not allow returns NOT_FOUND instead of claiming a status.

Route requests

The routing section selects an upstream for each request:

  • default is the fallback when no rule matches. It is optional; omit it to reject unmatched requests with an error.
  • system is the upstream for Namespace-less requests, such as the SDK's GetSystemInfo and GetClusterInfo calls. It is optional; when unset, those requests fall back to default.
  • rules is an ordered list, evaluated top to bottom. The first match wins.

Every upstream named by default, system, or a rule must exist in upstreams. Upstream name and hostPort values must each be unique across the list: two upstreams sharing a name make a routing reference ambiguous, and two sharing an address is a copy-paste error rather than a useful configuration.

routing:
default: local # Fallback when no rule matches.
system: cloud # Namespace-less requests.
rules:
- match:
namespace: 'prod-*'
metadata:
x-tier: gold
upstream: cloud
- match:
namespace: '*-test'
upstream: local

A rule matches when its Namespace matches and every metadata condition matches (AND logic). A match must set at least one of namespace or metadata; an empty match is a configuration error, since that is what default is for. Routing runs on the local Namespace, before translation.

namespace is a string literal or a simple glob with a single leading or trailing *:

PatternMatches
paymentsexactly payments
prod-*names starting with prod-
*-testnames ending with -test
*-test-*names containing -test-
*any Namespace

A * in any other position, such as a*b, is invalid.

metadata matches gRPC request metadata (headers). Keys are case-insensitive and do not support wildcards; values use the same glob syntax as namespace. A key matches when any of the request's values for it match.

Translate Namespaces

Applications connected to the proxy use short, local Namespace names. Each upstream rewrites those names to the ones its Temporal Service expects, under namespaces.rules. The rewrite applies to requests and is reversed on responses, so callers only ever see the local name.

upstreams:
- name: cloud
hostPort: '{{ .RemoteNamespace }}.tmprl.cloud:7233'
tls: {}
namespaces:
rules:
prefix: '' # Optional string prepended to the local name.
suffix: .acct # payments becomes payments.acct
overrides: # Explicit pairs that bypass prefix and suffix.
- local: billing
remote: payments.acct
  • prefix and suffix wrap every local Namespace: the remote name is prefix + local + suffix, and responses are unwrapped back to the local name.
  • overrides lists explicit local and remote pairs for names that do not follow the prefix and suffix convention. An override takes precedence over the prefix and suffix rules. Each local name and each remote name may appear only once.

An upstream's hostPort and tls.serverName can be Go templates resolved per request, so one upstream can serve many Namespaces. Available variables:

  • {{ .LocalNamespace }}: the Namespace before translation.
  • {{ .RemoteNamespace }}: the Namespace after translation.
  • {{ .Metadata.<key> }} or {{ index .Metadata "<key>" }}: a request metadata value.

Upstreams with a static hostPort connect eagerly at startup; templated ones connect lazily on first use.

Authenticate and authorize inbound requests

Inbound authentication runs on the gateway and is off by default: omit the top-level auth block to accept all requests. When present, auth must select exactly one authenticator: staticToken, jwks, or external. The gateway decides before the request is routed, so nothing reaches an upstream until the caller is admitted, and it strips the credential before forwarding upstream.

Compare an inbound bearer token against a fixed value with staticToken:

auth:
staticToken:
token: ${GATEWAY_TOKEN} # Required. The expected token value.
header: authorization # Header to read the token from.
scheme: Bearer # Scheme prefix to strip before comparing.

Or verify a JWT's signature and claims against a JWKS endpoint with jwks:

auth:
jwks:
url: https://issuer.example.com/.well-known/jwks.json # Required. Absolute https URL.
audiences:
- temporal-proxy
issuer: https://issuer.example.com/
header: authorization
scheme: Bearer

token (for staticToken) and url (for jwks) are required; the remaining fields are optional.

Delegate the decision to an extension server

For an identity system neither built-in authenticator covers, or for a decision that turns on more than who the caller is, point auth.external at an extension server you run. Declare the server under the top-level extensionServers block, the same way you would a key management backend, and the proxy asks it about every stream it accepts, forwarding only the ones it is told to admit.

extensionServers:
- name: authz
hostPort: 127.0.0.1:9444

auth:
external:
name: authz # Required. Names an entry in extensionServers.
credentialHeaders:
- authorization

name must match a configured extension server. credentialHeaders names the metadata headers that carry the caller's credentials: the proxy lifts those into the request it sends the extension server and removes them from the stream it forwards upstream, so a credential the server consumes never reaches the Temporal Service.

Declaring no headers does not hide the caller's credentials from the extension server, since the proxy forwards the caller's other metadata on the call either way. What you lose is the field naming them, so the server has to know which metadata to read and cannot tell a header the proxy vouches for from any other. Nothing is stripped before forwarding upstream either, so the caller's credential continues to the upstream alongside any credential configured for it.

The server implements api.auth.v1.AuthService, one RPC defined in api/auth/v1. Each request carries what the call is addressing and who is making it:

FieldCarries
target.full_nameThe gRPC full method being invoked, leading slash included. Always set.
target.namespaceThe Temporal Namespace the request names.
credentialsOne entry per declared header the caller sent, each with the canonical header name and every value sent under it.

Both target fields come from the stream rather than from anything the caller claims, so a caller cannot forge either by sending a header. target.namespace is empty when the method names no Namespace, when the caller sent no message to read one from, or when the service is not one the proxy forwards. Empty means unknown rather than a Namespace called nothing, so match a Namespace-scoped rule against full_name as well. credentials is empty when you declared no headers or the caller sent none of them, which is an unauthenticated caller rather than a trusted one.

Answer with a decision:

  • DECISION_ALLOW admits the caller and is the only value that does. A response left unfilled is DECISION_UNSPECIFIED, which denies, so there is no way to admit a caller by omission.
  • DECISION_DENY refuses the caller, who is told PERMISSION_DENIED.
  • reason is optional and written for whoever operates the server. The proxy records it and keeps it out of what a refused caller is told, so it can name internal systems or subjects.

Return a gRPC error only for reaching no verdict at all, such as a backend the server cannot itself reach. The proxy denies either way, but an error keeps its status code, so UNAVAILABLE or DEADLINE_EXCEEDED tells a Worker to retry where a denial tells it not to bother. A server that cannot reach its own backend should report that rather than admit the caller.

The authorization example maps a JWT to claims and then decides each call against them, the two steps Temporal Server splits across its ClaimMapper and Authorizer. It includes a Worker that cannot reach a second Namespace and an auditor that can read Workflow History but not start a Workflow.

Present credentials to upstreams

Each upstream can present its own credential to the Temporal Service, set under credentials. static is the only variant today; it injects a fixed API key as a bearer header on every outbound request, which is how you connect to Temporal Cloud:

upstreams:
- name: cloud
hostPort: my-ns.acct.tmprl.cloud:7233
tls: {} # Required whenever credentials are set.
credentials:
static:
apiKey: ${TEMPORAL_API_KEY} # Required.
header: authorization # Optional header override.
scheme: Bearer # Optional scheme override.

Credentials require TLS to the upstream. If you set credentials without a tls block, the configuration fails to load.

Configure TLS

TLS is terminated in two independent places, both using the same keys: ca, cert, key, and serverName. ca, cert, and key are paths to PEM files on disk, not inline PEM content. On Kubernetes, let the chart mount them from a Secret and fill in the paths for you, as described in Supply TLS material.

Inbound, on the gateway. The top-level tls block secures connections from your applications. Set cert and key for server TLS, and add ca to enforce mutual TLS, which requires each client to present a certificate signed by that CA. Local development commonly omits tls and connects in plaintext.

Outbound, per upstream. Each upstream's tls block secures the connection from its proxy to the Temporal Service:

  • tls: {} verifies the upstream against the system root certificate pool and presents no client certificate. This is what Temporal Cloud with an API key needs.
  • ca alone verifies the upstream against a private trust anchor, still presenting no client certificate.
  • cert and key together select mutual TLS and require ca. They must be set as a pair.

Set serverName when the host you dial does not match the common name or SAN on the server's certificate.

For payload encryption (envelope encryption, cloud KMS, and custom key backends), see Encrypt payloads.