Safelisting with persisted queries
Secure your graph while minimizing request latency
This feature is available only with a GraphOS Enterprise plan. If your organization doesn't currently have an Enterprise plan, you can test this functionality by signing up for a free Enterprise trial.
With GraphOS Enterprise, you can enhance your supergraph's security by maintaining a persisted query list (PQL) for your supergraph's self-hosted router. The Apollo Router checks incoming requests against the PQL, an operation safelist made by your first-party apps.
Your router can use its persisted query list (PQL) to both protect your supergraph and speed up your clients' operations:
- When you enable safelisting, your router rejects any incoming operations not registered in its PQL.
- Client apps can execute an operation by providing its PQL-specified ID instead of an entire operation string.
- Querying by ID can significantly reduce latency and bandwidth usage for very large operation strings.
- Your router can require that clients provide operations by ID and reject full operation strings—even operation strings present in the PQL.
Differences from automatic persisted queries
The Apollo Router also supports a related feature called automatic persisted queries (APQ). With APQ, clients can execute a GraphQL operation by sending the SHA256 hash of its operation string instead of the entire string. APQ doesn't support safelisting because the router dynamically populates its APQ cache over time with any operations it receives.
For more details on differences between APQ and this feature, see the GraphOS persisted queries documentation.
Implementation
Enabling operation safelisting has a few steps:
- PQL creation and linking
- Router configuration
- Preregistering trusted operations
- Client updates
This article details the router configuration step. For more information on other configuration aspects, see the GraphOS persisted queries documentation.
Router configuration
As soon as a graph has an associated PQL, you can configure router instances to fetch and use the PQL by following these steps:
Ensure your router instances are ready to work with PQLs:
- Make sure you're using version
1.25.0
or later of the Apollo Router. - Make sure your router instances are connected to your GraphOS Enterprise organization and that they're associated with a variant that your PQL is linked to.
- Make sure you're using version
Set your desired security level in your router's YAML config file. For supported options, see router security levels. When first implementing persisted queries, it's best to start with audit—or "dry run"—mode.
Deploy your updated router instances to begin using your PQL.
Once your organization's PQL has preregistered all your clients' operations and you've ensured your client apps are only sending preregistered operations, you can update your router configuration to the safelisting security level.
Router security levels
The Apollo Router supports the following security levels, in increasing order of restrictiveness:
- Allow operation IDs: Clients can optionally execute an operation on your router by providing the operation's PQL-specified ID.
- All other levels also provide this core capability.
- This level doesn't provide safelisting.
- Audit mode: Executing operations by providing a PQL-specified ID is still optional, but the router also logs any unregistered operations.
- The level serves as a dry run and helps you identify operations you may still need to preregister before turning on safelisting.
- Safelisting: The router rejects any incoming operations not present in its PQL. Requests can use either ID or operation string.
- Before moving to this security level, ensure all your client operations are present in your PQL.
- Safelisting with IDs only: The router rejects any freeform GraphQL operations. Clients can only execute operations by providing their PQL-specified IDs.
- Before moving to this security level, ensure all your clients execute operations by providing their PQL-specified ID.
When adopting persisted queries, you should start with a less restrictive security such as audit mode. You can then enable increasingly restrictive levels after your teams have updated all clients.
See below for sample YAML configurations for each level. Refer to the router configuration options for option details.
Allow operation IDs
To use persisted queries only to reduce network bandwidth and latency (not for safelisting), add the following minimal configuration:
preview_persisted_queries:enabled: true
Note: You can use this security level with or without automatic persisted queries enabled.
This mode lets clients execute operations by providing their PQL-specified ID instead of the full operation string. Your router also continues to accept full operation strings, even for operations that don't appear in its PQL.
Audit mode (dry run)
Turning on logging is crucial for gauging your client apps' readiness for safelisting. The logs identify which operations you need to either add to your PQL or stop your client apps from making.
To enable logging for unregistered queries, enable the log_unknown
property:
preview_persisted_queries:enabled: truelog_unknown: true
Note: You can use audit mode with or without automatic persisted queries enabled.
Unregistered operations appear in your router's logs.
For example:
2023-08-02T11:51:59.833534Z WARN [trace_id=5006cef73e985810eb086e5900945807] unknown operation operation_body="query ExampleQuery {\n me {\n id\n }\n}\n"
If your router receives an operation preregistered in the PQL, no log message will be output.
You can use these router logs to audit operations sent to your router and ask client teams to add new ones to your PQL if necessary.
Safelisting
⚠️ Before applying this configuration, ensure your PQL contains all GraphQL operations that all active versions of your clients execute. If you enable safelisting without ensuring this, your router will reject any unpublished client operations.
With the following configuration, your router allows only GraphQL operations that are present in its PQL while rejecting all other operations:
preview_persisted_queries:enabled: truelog_unknown: truesafelist:enabled: truerequire_id: falseapq:enabled: false # APQ must be turned off
Note: To enable safelisting, you must turn off automatic persisted queries (APQs). APQs let clients register arbitrary operations at runtime while safelisting restricts operations to those that have been explicitly preregistered.
To execute an operation, clients can provide its PQL-specified ID or full operation string.
The router rejects unregistered operations, and if log_unknown
is true, those operations appear in your router's logs.
So you can monitor the operations your router rejects, it's best to keep log_unknown
as true
while adopting safelisting. Once you're confident that all your clients are properly configured, you can turn it off to reduce noise in your logs.
Safelisting with IDs only
⚠️ Do not start with this configuration: It requires all your clients to execute operations by providing their PQL-specified ID. If any clients still provide full operation strings, the router rejects those operations, even if they're included in the safelist.
With the following configuration, your router rejects all operation strings and only accepts preregistered operation IDs:
preview_persisted_queries:enabled: truelog_unknown: truesafelist:enabled: truerequire_id: trueapq:enabled: false # APQ must be turned off
Note: To enable safelisting, you must turn off automatic persisted queries (APQs). APQs let clients register arbitrary operations at runtime while safelisting restricts operations to those that have been explicitly preregistered.
If you want to use this security level, you should always first set up safelisting with operation strings allowed. ID-only safelisting requires all your clients to execute operations via PQL-specified ID instead of an operation string. While making those necessary changes, you can use the less restrictive safelisting mode in your router.
With log_unknown
set to true, the router logs all rejected operations, including those preregistered to your PQL but that used the full operation string rather than the PQL-specified ID.
So you can monitor the operations your router rejects, it's best to keep log_unknown
as true
while adopting safelisting. Once you're confident that all your clients are properly configured, you can turn it off to reduce noise in your logs.
Configuration options
The router provides four configuration options that you can combine to create the recommended security levels. This section details each configuration option. Refer to the security levels section for recommended combinations.
preview_persisted_queries
This base configuration enables the feature. All other configuration options build off this one.
preview_persisted_queries:enabled: true
log_unknown
Adding log_unknown: true
to preview_persisted_queries
configures the router to log any incoming operations not preregistered to the PQL.
preview_persisted_queries:enabled: truelog_unknown: true
If used with the safelist
option, the router logs unregistered and rejected operations. With safelist.required_id
off, the only rejected operations are unregistered ones. If safelist.required_id
is turned on, operations can be rejected even when preregistered because they use operation IDs rather than operation strings.
safelist
Adding safelist: true
to preview_persisted_queries
causes the router to reject any operations that haven't been preregistered to your PQL.
preview_persisted_queries:enabled: truesafelist:enabled: trueapq:enabled: false
Note: To enable safelisting, you must turn off automatic persisted queries (APQs). APQs let clients register arbitrary operations at runtime while safelisting restricts operations to those that have been explicitly preregistered.
By default, the require_id
suboption is false
, meaning the router accepts both operation IDs and operation strings as long as the operation is preregistered.
require_id
Adding require_id: true
to the safelist
option causes the router to reject any operations that either:
- haven't been preregistered to your PQL
- use a full operation string rather than the operation ID
preview_persisted_queries:enabled: truesafelist:enabled: truerequire_id: trueapq:enabled: false
Note: To enable safelisting, you must turn off automatic persisted queries (APQs). APQs let clients register arbitrary operations at runtime while safelisting restricts operations to those that have been explicitly preregistered.