> ## Documentation Index > Fetch the complete documentation index at: https://docs.dataharbor.co/llms.txt > Use this file to discover all available pages before exploring further. # Control Block Reference > Detailed reference for all Control Block types. # Control Block Reference Detailed reference for all Control Block types and their options. In the current runtime, controls live inside a v0.3 Virtual API Configuration under `objects..controls`. This page documents the control entries themselves. ## Common Execution Rules | Rule | Behavior | | ---------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Ordering | Controls execute top-to-bottom | | Path syntax | Use dot notation, with array segments like `"[contacts].email"`. Slash notation is not supported. | | Filter targets | `redact`, `tokenize`, `anonymize`, `mask`, `hash`, and `allow` require scalar targets (`string`, `number`, or `bool`) | | Root arrays | If the matched payload is an array, controls apply to each object element automatically. Non-object elements are skipped. | | Array failure behavior | Array execution is not transactional across elements. If an earlier element succeeds and a later element fails a `required` check, the request fails and earlier element changes are not rolled back. | | Required semantics | `required: true` is full-path strict. Missing any intermediate parent or final target fails the request. | ## Common Options | Option | Applies to | Required | Description | | --------------- | --------------------- | -------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `fields` | All controls | Yes | Field paths to operate on | | `required` | All controls | No | When `true`, missing referenced fields fail instead of being skipped. That includes missing intermediate parent paths, not just the final field. For `coalesce`, all fields missing or empty also fails. | | `into` | `combine`, `coalesce` | Yes | Target field for the transformed value | | `separator` | `combine` | No | Separator inserted between combined string values. Default: `""` | | `remove_source` | `combine`, `coalesce` | No | Remove the source fields after the transform completes. Default: `false` | ## Data Control ### redact Remove sensitive data entirely. | Option | Type | Required | Description | | -------- | ------ | -------- | --------------------- | | `type` | string | Yes | Must be `redact` | | `fields` | array | Yes | Field paths to redact | **Behavior:** * Strings → `""` * Numbers → `0` * Booleans → `false` * Objects and arrays are invalid targets * The key remains in the output. If you want to remove the field entirely, use [`delete`](#delete) instead. ```yaml theme={null} - type: redact fields: - ssn - credit_card - user.password ``` *** ### tokenize Replace with deterministic tokens. | Option | Type | Required | Description | | -------- | ------ | -------- | ----------------------- | | `type` | string | Yes | Must be `tokenize` | | `fields` | array | Yes | Field paths to tokenize | **Behavior:** * Same input → same token within the same Virtual API and matched object definition * Different object definitions or different Virtual APIs → different tokens * Token format: `tok_[hash]` * Booleans are not supported ```yaml theme={null} - type: tokenize fields: - email - phone - customer_id ``` *** ### anonymize Replace with random values preserving structure. | Option | Type | Required | Description | | -------- | ------ | -------- | ------------------------ | | `type` | string | Yes | Must be `anonymize` | | `fields` | array | Yes | Field paths to anonymize | **Behavior:** * Each request produces different values * Format is preserved (email looks like email) * Not reversible, not correlatable ```yaml theme={null} - type: anonymize fields: - email - name - street_address ``` *** ### mask Partially redact values while preserving structure. | Option | Type | Required | Description | | -------- | ------ | -------- | ------------------- | | `type` | string | Yes | Must be `mask` | | `fields` | array | Yes | Field paths to mask | **Behavior:** * Strings → first and last characters visible, middle masked (e.g., `"John Smith"` → `"Jo** ***th"`) * Numbers → leading digits zeroed, last 2 visible (e.g., `5551234567` → `0000000067`) * Booleans → `false` ```yaml theme={null} - type: mask fields: - ssn - phone - name ``` *** ### hash Replace with one-way SHA-256 digest. Deterministic within the same Virtual API and matched object definition — same input always produces the same hash in the same scope. | Option | Type | Required | Description | | -------- | ------ | -------- | ------------------- | | `type` | string | Yes | Must be `hash` | | `fields` | array | Yes | Field paths to hash | **Behavior:** * Strings → 64-character hex digest * Numbers → deterministic number derived from hash bytes * Booleans → deterministic boolean ```yaml theme={null} - type: hash fields: - email - customer_id ``` *** ### allow Pass values through unchanged. Fields not referenced by any control are allowed by default — `allow` is provided for users who prefer to be explicit about which fields are permitted. | Option | Type | Required | Description | | -------- | ------ | -------- | -------------------- | | `type` | string | Yes | Must be `allow` | | `fields` | array | Yes | Field paths to allow | ```yaml theme={null} - type: allow fields: - public_id - display_name ``` *** ## Data Transform ### combine Merge fields into a new field. | Option | Type | Required | Description | | ----------- | ------ | -------- | --------------------------------------------- | | `type` | string | Yes | Must be `combine` | | `fields` | array | Yes | Fields to combine (order matters; at least 2) | | `into` | string | Yes | Name of new field | | `separator` | string | No | Separator between values. Default: `""` | All source fields must be strings. When you use nested paths, every entry in `fields` plus `into` must share the same parent path. If `into` already exists, the transform fails instead of overwriting it. ```yaml theme={null} - type: combine fields: - first_name - last_name into: full_name separator: " " remove_source: true ``` *** ### coalesce Select first non-empty value. | Option | Type | Required | Description | | -------- | ------ | -------- | ---------------------------------------------- | | `type` | string | Yes | Must be `coalesce` | | `fields` | array | Yes | Fields to check (order = priority; at least 2) | | `into` | string | Yes | Name of new field | `coalesce` treats missing values, `null`, and empty strings as empty. Whitespace-only strings, numeric `0`, boolean `false`, objects, and arrays are all treated as present values. When you use nested paths, every entry in `fields` plus `into` must share the same parent path. If `into` already exists, the transform fails instead of overwriting it. ```yaml theme={null} - type: coalesce fields: - mobile_phone - work_phone - home_phone into: primary_phone ``` *** ### delete Remove fields entirely from the outbound payload. | Option | Type | Required | Description | | -------- | ------ | -------- | ---------------- | | `type` | string | Yes | Must be `delete` | | `fields` | array | Yes | Fields to remove | `delete` does not support `into`. When you use nested paths, all entries in `fields` must share the same parent path. This keeps cleanup operations predictable for nested objects and arrays. ```yaml theme={null} - type: delete fields: - first_name - last_name - internal_note ``` *** ## Access Control Access controls are defined in the `access` block, not as Control Blocks. ### expires | Option | Type | Description | | --------- | ------ | ------------------------------------------------ | | `expires` | string | ISO 8601 date (`2025-12-31`) or relative (`90d`) | ```yaml theme={null} access: expires: 2025-12-31 ``` *** ### geo\_allow / geo\_deny | Option | Type | Description | | ----------- | ----- | ----------------------------------------- | | `geo_allow` | array | ISO 3166-1 alpha-2 country codes to allow | | `geo_deny` | array | ISO 3166-1 alpha-2 country codes to deny | ```yaml theme={null} access: geo_allow: - US - CA - EU # Special value: all EU countries ``` *** ### ip\_allow | Option | Type | Description | | ---------- | ----- | -------------------- | | `ip_allow` | array | CIDR ranges to allow | ```yaml theme={null} access: ip_allow: - 10.0.0.0/8 - 192.168.1.0/24 ``` *** ### rate\_limit | Option | Type | Description | | --------------------- | ------ | ------------------------------ | | `rate_limit.requests` | number | Max requests per period | | `rate_limit.period` | string | Time period (`1m`, `1h`, `1d`) | ```yaml theme={null} access: rate_limit: requests: 10000 period: 1d ``` *** ## Field path syntax ### Simple fields ```yaml theme={null} fields: - email - phone ``` ### Nested fields ```yaml theme={null} fields: - user.email - billing.address.street ``` ### Array items ```yaml theme={null} fields: - "[contacts].email" # All items in array - "[orders].[items].sku" # Nested arrays ```