SpiceDB Documentation
Concepts
Datastores

Datastores

In order to reduce operational complexity, SpiceDB leverages existing, popular systems for persisting data.

Each datastore implementation comes with various trade-offs.

  • CockroachDB - Recommended for planet-scale, multi-region deployments
  • Cloud Spanner - Recommended for Google Cloud deployments
  • PostgreSQL - Recommended for single-region deployments
  • MySQL - Not recommended; only use if you cannot use PostgreSQL
  • memdb - Recommended for local development and integration testing against applications

Migrations

Before a datastore can be used by SpiceDB or before running a new version of SpiceDB, you must execute all available migrations.

The only exception is the memdb datastore because it does not persist any data.

In order to migrate a datastore, run the following command with your desired values:

spicedb migrate head \
    --datastore-engine $DESIRED_ENGINE \
    --datastore-conn-uri $CONNECTION_STRING

For more information, refer to the Datastore Migration documentation.

CockroachDB

Usage Notes

⚠️

SpiceDB's Watch API requires CockroachDB's Experimental Changefeed (opens in a new tab) to be enabled.

  • Recommended for multi-region deployments, with configurable region awareness
  • Enables horizonally scalablity by adding more SpiceDB and CockroachDB instances
  • Resiliency to individual CockroachDB instance failures
  • Query and data balanced across the CockroachDB
  • Setup and operational complexity of running CockroachDB

Developer Notes

Configuration

Required Parameters

ParameterDescriptionExample
datastore-enginethe datastore engine--datastore-engine=cockroachdb
datastore-conn-uriconnection string used to connect to CRDB--datastore-conn-uri="postgres://user:password@localhost:26257/spicedb?sslmode=disable"

Optional Parameters

ParameterDescriptionExample
datastore-max-tx-retriesMaximum number of times to retry a query before raising an error--datastore-max-tx-retries=50
datastore-tx-overlap-strategyThe overlap strategy to prevent New Enemy on CRDB (see below)--datastore-tx-overlap-strategy=static
datastore-tx-overlap-keyThe key to use for the overlap strategy (see below)--datastore-tx-overlap-key="foo"
datastore-conn-max-idletimeMaximum idle time for a connection before it is recycled--datastore-conn-max-idletime=60s
datastore-conn-max-lifetimeMaximum lifetime for a connection before it is recycled--datastore-conn-max-lifetime=300s
datastore-conn-max-openMaximum number of concurrent connections to open--datastore-conn-max-open=10
datastore-conn-min-openMinimum number of concurrent connections to open--datastore-conn-min-open=1
datastore-query-split-sizeThe (estimated) query size at which to split a query into multiple queries--datastore-query-split-size=5kb
datastore-gc-windowSets the window outside of which overwritten relationships are no longer accessible--datastore-gc-window=1s
datastore-revision-fuzzing-durationSets a fuzzing window on all zookies/zedtokens--datastore-revision-fuzzing-duration=50ms
datastore-readonlyPlaces the datastore into readonly mode--datastore-readonly=true
datastore-follower-read-delay-durationAmount of time to subtract from non-sync revision timestamps to ensure follower reads--datastore-follower-read-delay-duration=4.8s
datastore-relationship-integrity-enabledEnables relationship integrity checks, only supported on CRDB--datastore-relationship-integrity-enabled=false
datastore-relationship-integrity-current-key-idCurrent key id for relationship integrity checks--datastore-relationship-integrity-current-key-id="foo"
datastore-relationship-integrity-current-key-filenameCurrent key filename for relationship integrity checks--datastore-relationship-integrity-current-key-filename="foo"
datastore-relationship-integrity-expired-keysConfig for expired keys for relationship integrity checks--datastore-relationship-integrity-expired-keys="foo"

Overlap Strategy

In distributed systems, you can trade-off consistency for performance.

CockroachDB datastore users that are willing to rely on more subtle guarantees to mitigate the New Enemy Problem can configure --datastore-tx-overlap-strategy.

The available strategies are:

StrategyDescription
static (default)All writes overlap to guarantee safety at the cost of write throughput
prefixOnly writes that contain objects with same prefix overlap (e.g. tenant1/user and tenant2/user can be written in concurrently)
requestOnly writes with the same io.spicedb.requestoverlapkey header overlap enabling applications to decide on-the-fly which writes have causual dependencies. Writes without any header act the same as insecure.
insecureNo writes overlap, providing the best write throughput, but possibly leaving you vulnerable to the New Enemy Problem

For more information, refer to the CockroachDB datastore README (opens in a new tab) or our blog post "The One Crucial Difference Between Spanner and CockroachDB (opens in a new tab)".

Garbage Collection Window

As of February 2023, the default garbage collection window (opens in a new tab) has changed to 1.25 hours for CockroachDB Serverless and 4 hours for CockroachDB Dedicated.

SpiceDB warns if the garbage collection window as configured in CockroachDB is smaller than the SpiceDB configuration.

If you need a longer time window for the Watch API or querying at exact snapshots, you can adjust the value in CockroachDB (opens in a new tab):

ALTER ZONE default CONFIGURE ZONE USING gc.ttlseconds = 90000;

Relationship Integrity

Relationship Integrity is a new experimental feature in SpiceDB that ensures that data written into the supported backing datastores (currently: only CockroachDB) is validated as having been written by SpiceDB itself.

  • What does relationship integrity ensure? Relationship integrity primarily ensures that all relationships written into the backing datastore were written via a trusted instance of SpiceDB or that the caller has access to the key(s) necessary to write those relationships. It ensures that if someone gains access to the underlying datastore, they cannot simply write new relationships of their own invention.

  • What does relationship integrity not ensure? Since the relationship integrity feature signs each individual relationship, it does not ensure that removal of relationships is by a trusted party. Schema is also currently unverified, so an untrusted party could change it as well. Support for schema changes will likely come in a future version.

Setting up relationship integrity To run with relationship integrity, new flags must be given to SpiceDB:

spicedb serve ...existing flags...
--datastore-relationship-integrity-enabled
--datastore-relationship-integrity-current-key-id="somekeyid"
--datastore-relationship-integrity-current-key-filename="some.key"

Place the generated key contents (which must support an HMAC key) in some.key

Deployment Process

  1. Start with a clean datastore for SpiceDB. At this time, migrating an existing SpiceDB installation is not supported.
  2. Run the standard migrate command but with relationship integrity flags included.
  3. Run SpiceDB with the relationship integrity flags included.

Cloud Spanner

Usage Notes

  • Requires a Google Cloud Account with an active Cloud Spanner instance
  • Take advantage of Google's TrueTime. The Spanner driver assumes the database is linearizable and skips the transaction overlap strategy required by CockroachDB.

Developer Notes

Configuration

  • The Cloud Spanner docs (opens in a new tab) outline how to set up an instance
  • Authentication via service accounts: The service account that runs migrations must have Cloud Spanner Database Admin; SpiceDB (non-migrations) must have Cloud Spanner Database User.

Required Parameters

ParameterDescriptionExample
datastore-enginethe datastore engine--datastore-engine=spanner
datastore-conn-urithe cloud spanner database identifier--datastore-conn-uri="projects/project-id/instances/instance-id/databases/database-id"

Optional Parameters

ParameterDescriptionExample
datastore-spanner-credentialsJSON service account token (omit to use application default credentials (opens in a new tab))--datastore-spanner-credentials=./spanner.json
datastore-gc-intervalAmount of time to wait between garbage collection passes--datastore-gc-interval=3m
datastore-gc-windowSets the window outside of which overwritten relationships are no longer accessible--datastore-gc-window=1s
datastore-revision-fuzzing-durationSets a fuzzing window on all zookies/zedtokens--datastore-revision-fuzzing-duration=50ms
datastore-readonlyPlaces the datastore into readonly mode--datastore-readonly=true
datastore-follower-read-delay-durationAmount of time to subtract from non-sync revision timestamps to ensure stale reads--datastore-follower-read-delay-duration=4.8s

PostgreSQL

Usage Notes

  • Recommended for single-region deployments
  • Postgres 15 or newer is required for optimal performance
  • Resiliency to failures only when PostgreSQL is operating with a follower and proper failover
  • Setup and operational complexity of running PostgreSQL
  • Does not rely on any non-standard PostgreSQL extensions
  • Compatible with managed PostgreSQL services (e.g. AWS RDS)
  • Can be scaled out on read workloads using read replicas
⚠️

SpiceDB's Watch API requires PostgreSQL's Commit Timestamp tracking (opens in a new tab) to be enabled.

This can be done by providing the --track_commit_timestamp=on flag, configuring postgresql.conf, or executing ALTER SYSTEM SET track_commit_timestamp = on; and restarting the instance.

Developer Notes

Read Replicas

SpiceDB supports Postgres read replicas and does it while retaining consistency guarantees. Typical use cases are:

  • scale read workloads/offload reads from the primary
  • deploy SpiceDB in other regions with primarily read workloads

Read replicas are typically configured with asynchronous replication, which involves replication lag. That would be problematic to SpiceDB's ability to solve the new enemy problem but it addresses the challenge by checking if a revision has been replicated into the target replica. If missing, it will fall back to the primary.

All API consistency options will leverage replicas, but the ones that benefit the most are those that involve some level of staleness as it increases the odds a revision has replicated. minimize_latency, at_least_as_fresh, and at_exact_snapshot consistency modes have the highest chance of being redirected to a replica.

SpiceDB supports Postgres replicas behind a load-balancer, and/or individually listing replica hosts. When multiple URIs are provided, they will be queried using a round-robin strategy.
Please note that the maximum number of replica URIs to list is 16.

Read replicas are configured with the --datastore-read-replica-* family of flags.

SpiceDB supports PgBouncer (opens in a new tab) connection pooler and is part of the test suite.

Configuration

Required Parameters

ParameterDescriptionExample
datastore-enginethe datastore engine--datastore-engine=postgres
datastore-conn-uriconnection string used to connect to PostgreSQL--datastore-conn-uri="postgres://postgres:password@localhost:5432/spicedb?sslmode=disable"

Optional Parameters

ParameterDescriptionExample
datastore-conn-max-idletimeMaximum idle time for a connection before it is recycled--datastore-conn-max-idletime=60s
datastore-conn-max-lifetimeMaximum lifetime for a connection before it is recycled--datastore-conn-max-lifetime=300s
datastore-conn-max-openMaximum number of concurrent connections to open--datastore-conn-max-open=10
datastore-conn-min-openMinimum number of concurrent connections to open--datastore-conn-min-open=1
datastore-query-split-sizeThe (estimated) query size at which to split a query into multiple queries--datastore-query-split-size=5kb
datastore-gc-windowSets the window outside of which overwritten relationships are no longer accessible--datastore-gc-window=1s
datastore-revision-fuzzing-durationSets a fuzzing window on all zookies/zedtokens--datastore-revision-fuzzing-duration=50ms
datastore-readonlyPlaces the datastore into readonly mode--datastore-readonly=true
datastore-read-replica-conn-uriConnection string used by datastores for read replicas; only supported for postgres and MySQL--datastore-read-replica-conn-uri="postgres://postgres:password@localhost:5432/spicedb\"
—datastore-read-replica-credentials-provider-nameRetrieve datastore credentials dynamically using aws-iam
--datastore-read-replica-conn-pool-read-healthcheck-intervalamount of time between connection health checks in a read-only replica datastore's connection pool--datastore-read-replica-conn-pool-read-healthcheck-interval=30s
--datastore-read-replica-conn-pool-read-max-idletimemaximum amount of time a connection can idle in a read-only replica datastore's connection pool--datastore-read-replica-conn-pool-read-max-idletime=30m
--datastore-read-replica-conn-pool-read-max-lifetimemaximum amount of time a connection can live in a read-only replica datastore's connection pool--datastore-read-replica-conn-pool-read-max-lifetime=30m
--datastore-read-replica-conn-pool-read-max-lifetime-jitterwaits rand(0, jitter) after a connection is open for max lifetime to actually close the connection to a read replica(default: 20% of max lifetime)--datastore-read-replica-conn-pool-read-max-lifetime-jitter=6m
--datastore-read-replica-conn-pool-read-max-opennumber of concurrent connections open in a read-only replica datastore's connection pool--datastore-read-replica-conn-pool-read-max-open=20
--datastore-read-replica-conn-pool-read-min-opennumber of minimum concurrent connections open in a read-only replica datastore's connection pool--datastore-read-replica-conn-pool-read-min-open=20

MySQL

Usage Notes

  • Recommended for single-region deployments
  • Setup and operational complexity of running MySQL
  • Does not rely on any non-standard MySQL extensions
  • Compatible with managed MySQL services
  • Can be scaled out on read workloads using read replicas

Developer Notes

Read Replicas

⚠️

Do not use a load balancer between SpiceDB and MySQL replicas because SpiceDB will not be able to maintain consistency guarantees.

SpiceDB supports MySQL read replicas and does it while retaining consistency guarantees. Typical use cases are:

  • scale read workloads/offload reads from the primary
  • deploy SpiceDB in other regions with primarily read workloads

Read replicas are typically configured with asynchronous replication, which involves replication lag. That would be problematic to SpiceDB's ability to solve the new enemy problem but it addresses the challenge by checking if the revision has been replicated into the target replica. If missing, it will fall back to the primary. Compared to the Postgres implementation, MySQL support requires two roundtrips instead of one, which means it adds some extra latency overhead.

All API consistency options will leverage replicas, but the ones that benefit the most are those that involve some level of staleness as it increases the odds a revision has replicated. minimize_latency, at_least_as_fresh, and at_exact_snapshot consistency modes have the highest chance of being redirected to a replica.

SpiceDB does not support MySQL replicas behind a load-balancer: you may only list replica hosts individually. Failing to adhere to this would compromise consistency guarantees. When multiple host URIs are provided, they will be queried using round-robin. Please note that the maximum number of MySQL replica host URIs to list is 16.

Read replicas are configured with the --datastore-read-replica-* family of flags.

Configuration

Required Parameters

ParameterDescriptionExample
datastore-enginethe datastore engine--datastore-engine=mysql
datastore-conn-uriconnection string used to connect to MySQL--datastore-conn-uri="user:password@(localhost:3306)/spicedb?parseTime=True"
⚠️

SpiceDB requires --datastore-conn-uri to contain the query parameter parseTime=True.

Optional Parameters

ParameterDescriptionExample
datastore-conn-max-idletimeMaximum idle time for a connection before it is recycled--datastore-conn-max-idletime=60s
datastore-conn-max-lifetimeMaximum lifetime for a connection before it is recycled--datastore-conn-max-lifetime=300s
datastore-conn-max-openMaximum number of concurrent connections to open--datastore-conn-max-open=10
datastore-query-split-sizeThe (estimated) query size at which to split a query into multiple queries--datastore-query-split-size=5kb
datastore-gc-windowSets the window outside of which overwritten relationships are no longer accessible--datastore-gc-window=1s
datastore-revision-fuzzing-durationSets a fuzzing window on all zookies/zedtokens--datastore-revision-fuzzing-duration=50ms
datastore-mysql-table-prefix stringPrefix to add to the name of all SpiceDB database tables--datastore-mysql-table-prefix=spicedb
datastore-readonlyPlaces the datastore into readonly mode--datastore-readonly=true
datastore-read-replica-conn-uriConnection string used by datastores for read replicas; only supported for postgres and MySQL--datastore-read-replica-conn-uri="postgres://postgres:password@localhost:5432/spicedb\"
—datastore-read-replica-credentials-provider-nameRetrieve datastore credentials dynamically using aws-iam
--datastore-read-replica-conn-pool-read-healthcheck-intervalamount of time between connection health checks in a read-only replica datastore's connection pool--datastore-read-replica-conn-pool-read-healthcheck-interval=30s
--datastore-read-replica-conn-pool-read-max-idletimemaximum amount of time a connection can idle in a read-only replica datastore's connection pool--datastore-read-replica-conn-pool-read-max-idletime=30m
--datastore-read-replica-conn-pool-read-max-lifetimemaximum amount of time a connection can live in a read-only replica datastore's connection pool--datastore-read-replica-conn-pool-read-max-lifetime=30m
--datastore-read-replica-conn-pool-read-max-lifetime-jitterwaits rand(0, jitter) after a connection is open for max lifetime to actually close the connection to a read replica(default: 20% of max lifetime)--datastore-read-replica-conn-pool-read-max-lifetime-jitter=6m
--datastore-read-replica-conn-pool-read-max-opennumber of concurrent connections open in a read-only replica datastore's connection pool--datastore-read-replica-conn-pool-read-max-open=20
--datastore-read-replica-conn-pool-read-min-opennumber of minimum concurrent connections open in a read-only replica datastore's connection pool--datastore-read-replica-conn-pool-read-min-open=20

memdb

Usage Notes

  • Fully ephemeral; all data is lost when the process is terminated
  • Intended for usage with SpiceDB itself and testing application integrations
  • Cannot be ran highly-available as multiple instances will not share the same in-memory data

If you need an ephemeral datastore designed for validation or testing, see the test server system in Validating and Testing

Developer Notes

Configuration

Required Parameters

ParameterDescriptionExample
datastore-enginethe datastore engine--datastore-engine memory

Optional Parameters

ParameterDescriptionExample
datastore-revision-fuzzing-durationSets a fuzzing window on all zookies/zedtokens--datastore-revision-fuzzing-duration=50ms
datastore-gc-windowSets the window outside of which overwritten relationships are no longer accessible--datastore-gc-window=1s
datastore-readonlyPlaces the datastore into readonly mode--datastore-readonly=true
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