Bundling JSON Schemas

Bundling creates a single schema document that contains a root schema and all schemas it references. This is useful when sharing schemas with other teams or shipping self-contained validation assets.

In JsonSchema.Net, bundling is performed by SchemaRegistry.CreateBundle().

How bundling works

CreateBundle(rootUri, bundleUri, options) will create a new Draft 2020-12 schema that:

• sets $id to bundleUri
• sets top-level $ref to rootUri
• adds a $defs keyword for the root schema as well as any schemas it references

The keys in $defs are the resolved reference URIs as strings.

The process traverses only standard $ref references. Dynamic and recursive references ($dynamicRef, $recursiveRef) are not supported for bundling and will throw NotSupportedException.

If a referenced document cannot be resolved, RefResolutionException is thrown.

If rootUri cannot be found in the registry, the method returns null.

Prerequisites

Before bundling:

• ensure the root schema is available in a SchemaRegistry
• ensure all referenced schemas are either:
  • pre-registered in that registry, or
  • resolvable via SchemaRegistry.Fetch

Bundling does not infer schemas from arbitrary files. References must resolve through the registry.

Basic example

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_ = JsonSchema.FromText(
 """
 {
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "$id": "https://schemas.example.com/person",
 "type": "object",
 "properties": {
 "address": { "$ref": "https://schemas.example.com/address" }
 }
 }
 """);

_ = JsonSchema.FromText(
 """
 {
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "$id": "https://schemas.example.com/address",
 "type": "object",
 "properties": {
 "street": { "type": "string" },
 "postalCode": { "type": "string" }
 },
 "required": ["street", "postalCode"]
 }
 """);

var bundled = SchemaRegistry.Global.CreateBundle(
 new Uri("https://schemas.example.com/person"),
 new Uri("https://schemas.example.com/person.bundle")
);

if (bundled is null)
 throw new InvalidOperationException("Root schema was not found.");

The resulting bundle will have this shape:

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{"$schema":"https://json-schema.org/draft/2020-12/schema","$id":"https://schemas.example.com/person.bundle","$ref":"https://schemas.example.com/person","$defs":{"https://schemas.example.com/person":{"...":"root schema"},"https://schemas.example.com/address":{"...":"referenced schema"}}}

Build options

You can pass a BuildOptions instance as the third parameter when creating the bundle.

If options is omitted, CreateBundle() will use the global registry.

Use custom options when you need specific build behavior (for example, custom dialect/registry settings used by your environment).

When to use bundling

Bundling is a good fit when:

• consumers need a single document instead of a graph of remote references
• deployment environments have restricted network access
• schema artifacts are versioned and distributed as build outputs

For interactive or frequently changing schema graphs, keeping references external can still be a better operational model.