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Essentials
Schema Validation

Schema Validation

Detect changes to your GraphQL Schema and prevent breaking your existing applications. With GraphQL Inspector you get a list of breaking, potentially dangerous and safe changes on every Pull Request. Integrate it with GitHub, BitBucket, GitLab or any Continuous Integration.

Application

Using GitHub Application

Install our GitHub Application to check Pull Requests and commits.

Using GitHub Action

Use our GitHub Action in few steps.

Using in CI

GraphQL Inspector offers a version of our CLI that is better suited for Continuous Integrations. Learn more how to use it.

Using CLI

Detected following changes:
 
 Field posts was removed from object type Query
 Field modifiedAt was removed from object type Post
 Field Post.id changed typed from ID to ID!
 Deprecation reason "No more used" on field Post.title was added
 
ERROR Detected 2 breaking changes!

Usage

Run the following command:

graphql-inspector diff OLD_SCHEMA NEW_SCHEMA

Arguments

Flags

  • -r, --require <s> - require a module
  • -t, --token <s> - an access token
  • -h, --header <s> - set http header (`--header 'Auth: Basic 123')
  • --method - method on url schema pointers (default: POST)
  • --federation - Support Apollo Federation directives (default: false)
  • --aws - Support AWS Appsync directives and scalar types (default: false)

Output

A list of all differences between two schemas. GraphQL Inspector defines three kinds of changes:

  • Non-breaking change
  • Dangerous Change
  • Breaking change

When there's at least one breaking change, the process fails, otherwise, it succeeds.

Examples

Compare your local schema against a remote server:

graphql-inspector diff https://api.com/graphql schema.graphql

Compare your local schema against a schema on a master branch (GitHub):

graphql-inspector diff github:user/repo#master:schema.graphql schema.graphql

Rules

To customize the diff's behavior, you're able to use a set of rules:

dangerousBreaking

Turns every dangerous change to be a breaking change.

graphql-inspector diff https://api.com/graphql schema.graphql --rule dangerousBreaking

suppressRemovalOfDeprecatedField

Every removal of a deprecated field is considered a breaking change. With that flag, you can turn it into a dangerous change, so it won't fail a process or a CI check.

graphql-inspector diff https://api.com/graphql schema.graphql --rule suppressRemovalOfDeprecatedField

Here is an example of a breaking change:

OLD_SCHEMA
type User {
  id: ID
  name: String
  age: Int @deprecated
}
NEW_SCHEMA
type User {
  id: ID
  name: String
}
  • When "suppressRemovalOfDeprecatedField" rule enabled, it will not consider the removal of the age field as a breaking change.

ignoreDescriptionChanges

Changes in descriptions are filtered out and are not displayed in the CLI result.

graphql-inspector diff https://api.com/graphql schema.graphql --rule ignoreDescriptionChanges

safeUnreachable

Breaking changes are done on unreachable parts of the schema (non-accessible when starting from the root types) and won't be marked as breaking.

graphql-inspector diff https://api.com/graphql schema.graphql --rule safeUnreachable

Example of unreachable type:

type Query {
  me: String
}
 
"""
User can't be requested, it's unreachable
"""
type User {
  id: ID!
}

considerUsage

Decides if a breaking change is in fact breaking, based on real usage of schema.

graphql-inspector diff https://api.com/graphql schema.graphql --rule considerUsage --onUsage check-usage.js

Example check-usage.js file:

check-usage.js
const BREAKING = false
const NOT_BREAKING = true
 
module.exports = entities => {
  return Promise.all(
    entities.map(async ({ type, field, argument }) => {
      // User                   => { type: 'User' }
      // Query.id               => { type: 'Query', field: 'me' }
      // Query.users(last: 10)  => { type: 'Query', field: 'users', argument: 'last' }
      const used = await checkIfUsedInLast30Days(type, field, argument)
      return used ? BREAKING : NOT_BREAKING
    })
  )
}

Custom rules

It's possible to write your own rules.

First, you need a module:

custom-rule.js
module.exports = ({ changes }) => {
  return changes.filter(myCustomFilter)
}

Now, you can use that module as a rule:

graphql-inspector diff https://api.com/graphql schema.graphql --rule './custom-rule.js'

Passing different headers to multiple remote schemas

If you want to do a diff between multiple remote schemas, each with a different set of authentication headers, you can do it with --left-header and --right-header flags like so:

graphql-inspector diff http://your-schema-1/graphql http://your-schema-2/graphql --left-header 'Auth: Basic 123' --right-header 'Auth: Basic 345'

where --left-header will get passed to http://your-schema-1/graphql and --right-header will get passed to http://your-schema-2/graphql.

💡
Note: --left-header and --right-header overrides the --header flags.