Redis PubSub
Last updated: 4 minutes read.
Consume from a Redis publish/subscribe channel using either the SUBSCRIBE or PSUBSCRIBE commands.
Common
# Common config fields, showing default values
input:
label: ""
redis_pubsub:
url: redis://:6397 # No default (required)
channels: [] # No default (required)
use_patterns: false
auto_replay_nacks: true
Advanced
# All config fields, showing default values
input:
label: ""
redis_pubsub:
url: redis://:6397 # No default (required)
kind: simple
master: ""
tls:
enabled: false
skip_cert_verify: false
enable_renegotiation: false
root_cas: ""
root_cas_file: ""
client_certs: []
channels: [] # No default (required)
use_patterns: false
auto_replay_nacks: true
In order to subscribe to channels using the PSUBSCRIBE
command set the field use_patterns
to true
, then you can include glob-style patterns in your channel names. For example:
h?llo
subscribes to hello, hallo and hxlloh*llo
subscribes to hllo and heeeelloh[ae]llo
subscribes to hello and hallo, but not hillo
Use \
to escape special characters if you want to match them verbatim.
Fields
url
The URL of the target Redis server. Database is optional and is supplied as the URL path.
Type: string
# Examples
url: redis://:6397
url: redis://localhost:6379
url: redis://foousername:foopassword@redisplace:6379
url: redis://:foopassword@redisplace:6379
url: redis://localhost:6379/1
url: redis://localhost:6379/1,redis://localhost:6380/1
kind
Specifies a simple, cluster-aware, or failover-aware redis client.
Type: string
Default: "simple"
Options: simple
, cluster
, failover
.
master
Name of the redis master when kind
is failover
Type: string
Default: ""
# Examples
master: mymaster
tls
Custom TLS settings can be used to override system defaults.
Troubleshooting
Some cloud hosted instances of Redis (such as Azure Cache) might need some hand holding in order to establish stable connections. Unfortunately, it is often the case that TLS issues will manifest as generic error messages such as “i/o timeout”. If you’re using TLS and are seeing connectivity problems consider setting enable_renegotiation
to true
, and ensuring that the server supports at least TLS version 1.2.
Type: object
tls.enabled
Whether custom TLS settings are enabled.
Type: bool
Default: false
tls.skip_cert_verify
Whether to skip server side certificate verification.
Type: bool
Default: false
tls.enable_renegotiation
Whether to allow the remote server to repeatedly request renegotiation. Enable this option if you’re seeing the error message local error: tls: no renegotiation
.
Type: bool
Default: false
tls.root_cas
An optional root certificate authority to use. This is a string, representing a certificate chain from the parent trusted root certificate, to possible intermediate signing certificates, to the host certificate.
Type: string
Default: ""
# Examples
root_cas: |-
-----BEGIN CERTIFICATE-----
...
-----END CERTIFICATE-----
tls.root_cas_file
An optional path of a root certificate authority file to use. This is a file, often with a .pem extension, containing a certificate chain from the parent trusted root certificate, to possible intermediate signing certificates, to the host certificate.
Type: string
Default: ""
# Examples
root_cas_file: ./root_cas.pem
tls.client_certs
A list of client certificates to use. For each certificate either the fields cert
and key
, or cert_file
and key_file
should be specified, but not both.
Type: array
Default: []
# Examples
client_certs:
- cert: foo
key: bar
client_certs:
- cert_file: ./example.pem
key_file: ./example.key
tls.client_certs[].cert
A plain text certificate to use.
Type: string
Default: ""
tls.client_certs[].key
A plain text certificate key to use.
Type: string
Default: ""
tls.client_certs[].cert_file
The path of a certificate to use.
Type: string
Default: ""
tls.client_certs[].key_file
The path of a certificate key to use.
Type: string
Default: ""
tls.client_certs[].password
A plain text password for when the private key is password encrypted in PKCS#1 or PKCS#8 format. The obsolete pbeWithMD5AndDES-CBC
algorithm is not supported for the PKCS#8 format. Warning: Since it does not authenticate the ciphertext, it is vulnerable to padding oracle attacks that can let an attacker recover the plaintext.
Type: string
Default: ""
# Example
password: foo
channels
A list of channels to consume from.
Type: array
use_patterns
Whether to use the PSUBSCRIBE command, allowing for glob-style patterns within target channel names.
Type: bool
Default: false
auto_replay_nacks
Whether messages that are rejected (nacked) at the output level should be automatically replayed indefinitely, eventually resulting in back pressure if the cause of the rejections is persistent. If set to false
these messages will instead be deleted. Disabling auto replays can greatly improve memory efficiency of high throughput streams as the original shape of the data can be discarded immediately upon consumption and mutation.
Type: bool
Default: true