redis: Interacting with a Redis database

The redis built-in function allow you to interact with a Redis database.

info

Check out our tutorial on querying Redis.

redis.query

The redis.query function allows you to make a query against a Redis database.

Parameter	Type	Required	Default	Description
addr	String	Yes		Address to connect to Redis at.
db	Int	No	0	Redis database to use.
auth	Object	No		See Auth
cache	Bool	No	false	Cache the results of queries.
cache_duration	Integer	No	60	Duration (in seconds) to keep cached query results.
raise_error	Bool	No	true	See Errors.
command	String	Yes		Redis command to execute. This field is case-insensitive.
args	Array	Yes		Arguments to pass to the Redis command.

Note that only the following Redis commands are supported. Using a Redis command not in the list below as the value for the command field will cause Enterprise OPA to exit with an error.

• get
• getrange
• hexists
• hget
• hgetall
• hkeys
• hlen
• hmget
• hrandfield
• lindex
• llen
• lpos
• lrange
• mget
• scard
• sdiff
• sinter
• sintercard
• sismember
• smembers
• smismember
• srandmember
• strlen
• sunion

Example usage

redis.query({
  "addr": "localhost:6379",
  "auth": {
    "password": "letmein1!",
  },
  "command": "get",
  "args": ["some string key"]
}) # => { "results": "<value associated with 'some string key'>" }

Auth

Parameter	Type	Required	Default	Description
auth.username	String	No	(empty string)	Stores the username to connect to the Redis server with.
auth.password	String	No	(empty string)	Stores the password of the Redis server to connect to. If the database does not require a password, an empty string should may be used, or the field may be omitted entirely.

Errors

By default—and if raise_error is true—then an error returned will halt policy evaluation.

If raise_error is false, then the response object contains the error in an error key instead of its usual response.

{
  "error": ...
}

Utility helpers

Enterprise OPA comes with a helper method for using this builtin together with vault.send: redis.query.

This method is available in Enterprise OPA at data.system.eopa.utils.redis.v1.vault.

package example
import data.system.eopa.utils.redis.v1.vault as redis

example_1 := redis.query({"addr": " ... ", "command": " ... ", "args": [ ... ]})
# => {"results": [ ... ]}

The utility method will lookup connection data from a map it expects to find in Vault, under the path secret/redis:

{
  "username": "...",
  "password": "...",
}

See Auth for more information.

To override the secret path within Vault, use:

package example
import data.system.eopa.utils.redis.v1.vault as redis

redis_query(req) := result {
  result := redis.query(req)
    with redis.override.secret_path as "secret/prod/eopa-redis"

example_2 := redis_query({"addr": " ... ", "command": " ... ", "args": [ ... ]})
) # => {"results": ... }

If you need to override the Vault address or token, you can use this:

package example
import data.system.eopa.utils.vault.v1.env as vault
import data.system.eopa.utils.redis.v1.vault as redis

redis_query(req) := result {
  result := redis.query(req)
    with redis.override.secret_path as "secret/prod/eopa-redis"
    with vault.override.address as "localhost"
    with vault.override.token as "dev-token-2"
}

example_3 := redis_query({"addr": " ... ", "command": " ... ", "args": [ ... ]})
) # => {"results": [ ... ]}