Security & best practices
- Strict HTTP method checking
- Ensure requests are GET or POST
- CSRF protection
- Protect destructive actions from cross-site request forgery
- Cross-Origin Resource Sharing (CORS)
- Ensure that requests to your API come from a whitelist of origins
- Authentication
- Ensure your GraphQL api is only accessible to provisioned users
- Recursive or complex queries
- Protecting against potentially malicious queries
Recursive or complex queries
GraphQL schemas can contain recursive types and circular dependencies. Recursive or overly complex queries can take up a lot of resources, and could have a high impact on server performance and even result in a denial of service if not handled carefully.
Before parsing queries, if a query is found to have more than 500 nodes, it is rejected. While executing queries there is a default query depth limit of 15 for all schemas with no complexity limit.
You can customise the node limit and query depth and complexity limits by setting the following configuration:
# app/_config/graphql.yml
---
After: 'graphql-schema-global'
---
SilverStripe\GraphQL\Schema\Schema:
schemas:
'*':
config:
max_query_nodes: 250 # default 500
max_query_depth: 20 # default 15
max_query_complexity: 100 # default unlimitedFor calculating the query complexity, every field in the query gets a default score 1 (including ObjectType nodes). Total complexity of the query is the sum of all field scores.
You can also configure these settings for individual schemas. This allows you to fine-tune the security of your custom public-facing schema without affecting the security of the schema used in the CMS. To do so, either replace '*' with the name of your schema in the YAML configuration above, or set the values under the config key for your schema using preferred file structure as defined in configuring your schema. For example:
# app/_graphql/config.yml
max_query_nodes: 250
max_query_depth: 20
max_query_complexity: 100