Schema6 min read•Audience: Developers

Template JSON Schema Specification

Formal schema definition for the PostBrix template document format, block tree relationships, and email settings.

Key Takeaways

Document structure: an array of root-level Section blocks and optional EmailSettings.
Strict validation rules enforced by the AST normalizer before MJML compilation.
TypeScript interface specifications for full programmatic compatibility.

JSON Schema Definition#

code

json

{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "title": "PostBrixTemplate",
  "type": "object",
  "properties": {
    "settings": {
      "type": "object",
      "properties": {
        "subject": { "type": "string" },
        "preheader": { "type": "string" },
        "darkMode": {
          "type": "object",
          "properties": {
            "enabled": { "type": "boolean" },
            "backgroundColor": { "type": "string" },
            "textColor": { "type": "string" }
          }
        }
      }
    },
    "blocks": {
      "type": "array",
      "items": { "$ref": "#/definitions/EmailBlock" }
    }
  },
  "definitions": {
    "EmailBlock": {
      "type": "object",
      "required": ["id", "type"],
      "properties": {
        "id": { "type": "string" },
        "type": { "type": "string" },
        "attributes": { "type": "object" },
        "styles": { "type": "object" },
        "content": { "type": "string" },
        "children": {
          "type": "array",
          "items": { "$ref": "#/definitions/EmailBlock" }
        },
        "hidden": { "type": "boolean" }
      }
    }
  }
}

AST Validation in CI/CD#

You can validate template AST files before submitting them to the PostBrix API:

Validate with standard JSON schema validators (such as ajv in Node.js or jsonschema in Python).
Confirms that required block IDs and types are present and attribute types match schema definitions.

Frequently Asked Questions

Are block IDs required to follow a specific format?

Block IDs must be unique strings within the document (e.g. "sec_1a2b", "col_3c4d", "btn_5e6f"). We recommend alphanumeric strings with prefixes.

Can I include custom metadata in the template document?

Yes. The root settings object accepts arbitrary metadata keys (like { "settings": { "tags": ["transactional", "billing"] } }).

Reference

Block Reference

Developers

JSON Schema Guide

PreviousEmail CSS & Styling Support Guide NextExported HTML Technical Specification

Schema6 min read•Audience: Developers

Template JSON Schema Specification

Formal schema definition for the PostBrix template document format, block tree relationships, and email settings.

Key Takeaways

Document structure: an array of root-level Section blocks and optional EmailSettings.
Strict validation rules enforced by the AST normalizer before MJML compilation.
TypeScript interface specifications for full programmatic compatibility.

JSON Schema Definition#

code

json

{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "title": "PostBrixTemplate",
  "type": "object",
  "properties": {
    "settings": {
      "type": "object",
      "properties": {
        "subject": { "type": "string" },
        "preheader": { "type": "string" },
        "darkMode": {
          "type": "object",
          "properties": {
            "enabled": { "type": "boolean" },
            "backgroundColor": { "type": "string" },
            "textColor": { "type": "string" }
          }
        }
      }
    },
    "blocks": {
      "type": "array",
      "items": { "$ref": "#/definitions/EmailBlock" }
    }
  },
  "definitions": {
    "EmailBlock": {
      "type": "object",
      "required": ["id", "type"],
      "properties": {
        "id": { "type": "string" },
        "type": { "type": "string" },
        "attributes": { "type": "object" },
        "styles": { "type": "object" },
        "content": { "type": "string" },
        "children": {
          "type": "array",
          "items": { "$ref": "#/definitions/EmailBlock" }
        },
        "hidden": { "type": "boolean" }
      }
    }
  }
}

AST Validation in CI/CD#

You can validate template AST files before submitting them to the PostBrix API:

Validate with standard JSON schema validators (such as ajv in Node.js or jsonschema in Python).
Confirms that required block IDs and types are present and attribute types match schema definitions.

Frequently Asked Questions

Are block IDs required to follow a specific format?

Block IDs must be unique strings within the document (e.g. "sec_1a2b", "col_3c4d", "btn_5e6f"). We recommend alphanumeric strings with prefixes.

Can I include custom metadata in the template document?

Yes. The root settings object accepts arbitrary metadata keys (like { "settings": { "tags": ["transactional", "billing"] } }).

Reference

Block Reference

Developers

JSON Schema Guide

PreviousEmail CSS & Styling Support Guide NextExported HTML Technical Specification

Template JSON Schema Specification

Key Takeaways

JSON Schema Definition#

AST Validation in CI/CD#

Frequently Asked Questions

Are block IDs required to follow a specific format?

Can I include custom metadata in the template document?

Related Articles

Template JSON Schema Specification

Key Takeaways

JSON Schema Definition#

AST Validation in CI/CD#

Frequently Asked Questions

Are block IDs required to follow a specific format?

Can I include custom metadata in the template document?

Related Articles