Formatting Phone Numbers in Genesys Cloud Architect Using Expressions

What You Will Build

• A working Architect flow that ingests a raw E.164 phone number string (e.g., +14155551234) and transforms it into a standard US format (415) 555-1234.
• This solution uses the Genesys Cloud CX Architect Expression Engine and standard string manipulation functions.
• The programming context is the Genesys Cloud Architect visual interface, supplemented by Python SDK code to validate the logic via the /api/v2/architect/flows endpoint.

Prerequisites

• OAuth Client Type: Service Account or User Account with architect:flow:read and architect:flow:write scopes.
• SDK Version: genesys-cloud-purecloud-platform-client v2.0+ (Python) or equivalent for your language.
• Language/Runtime: Python 3.9+ for the SDK validation script; Genesys Cloud Architect for the expression logic.
• External Dependencies:

  pip install genesys-cloud-purecloud-platform-client
  

Authentication Setup

Before interacting with the Architect API to save or validate flows, you must establish an authenticated session. The following Python script demonstrates the standard OAuth2 Client Credentials flow required to obtain an access token.

import os
from purecloudplatformclientv2 import (
    Configuration,
    ApiClient,
    ArchitectApi,
    Flow
)

def get_purecloud_api_client() -> ApiClient:
    """
    Configures and returns a PureCloud API client with OAuth authentication.
    """
    configuration = Configuration()
    configuration.host = "https://api.mypurecloud.com"
    
    # Use environment variables for security. Never hardcode credentials.
    configuration.client_id = os.environ.get("GENESYS_CLIENT_ID")
    configuration.client_secret = os.environ.get("GENESYS_CLIENT_SECRET")
    
    if not configuration.client_id or not configuration.client_secret:
        raise ValueError("GENESYS_CLIENT_ID and GENESYS_CLIENT_SECRET environment variables must be set.")

    api_client = ApiClient(configuration)
    return api_client

# Initialize the API client
api_client = get_purecloud_api_client()
architect_api = ArchitectApi(api_client)

OAuth Scopes Required:

• architect:flow:read: To retrieve existing flows.
• architect:flow:write: To create or update flows with the new expression logic.

Implementation

Genesys Cloud Architect expressions are based on JavaScript-like syntax but run in a sandboxed environment. They do not support external libraries like libphonenumber. Therefore, we must use native string methods: substring, replace, and conditional logic.

Step 1: Validating and Extracting the Core Number

The input format is E.164: +1XXXXXXXXXX. We need to strip the +1 country code to isolate the 10-digit National Significant Number (NSN).

Architect Expression Logic:

1. Check if the string starts with +1.
2. If yes, extract the last 10 characters.
3. If no, assume the input is already a 10-digit string or handle as an error.

Expression:

if (startsWith(phoneInput, "+1")) {
    substring(phoneInput, 2)
} else {
    phoneInput
}

Note: In Architect, startsWith and substring are available functions. substring(string, start_index) extracts from the start index to the end of the string.

Step 2: Constructing the Formatted String

Now that we have the 10-digit NSN (e.g., 4155551234), we need to insert parentheses, spaces, and hyphens.

Target Format: (XXX) XXX-XXXX

We will use substring to slice the 10-digit string into three parts:

1. Area Code: indices 0-3 (length 3)
2. Prefix: indices 3-6 (length 3)
3. Line Number: indices 6-10 (length 4)

Architect Expression:

let nsn = if (startsWith(phoneInput, "+1")) { substring(phoneInput, 2) } else { phoneInput };

// Ensure we have exactly 10 digits before formatting
if (length(nsn) == 10) {
    concat("(", substring(nsn, 0, 3), ") ", substring(nsn, 3, 3), "-", substring(nsn, 6, 4))
} else {
    "Invalid Number"
}

Breakdown of Functions:

• length(nsn): Returns the character count.
• substring(nsn, start, length): Extracts a specific segment. Note that in Genesys Cloud Architect, the second argument is the length of the substring, not the end index (unlike standard JavaScript).
  • substring(nsn, 0, 3) gets the first 3 characters (Area Code).
  • substring(nsn, 3, 3) gets the next 3 characters (Prefix).
  • substring(nsn, 6, 4) gets the last 4 characters (Line Number).
• concat(...): Joins the strings and literals together.

Step 3: Embedding the Expression in a Flow Action

To make this usable, we place the expression inside a Set Data action within the Architect flow.

1. Add a Set Data action to your flow.
2. Create a new data node, e.g., formattedPhone.
3. Set the value type to Expression.
4. Paste the combined logic from Step 2.

Complete Expression for Set Data Action:

let raw = inputData.phone;
let ns = if (startsWith(raw, "+1")) { substring(raw, 2) } else { raw };
if (length(ns) == 10) {
    concat("(", substring(ns, 0, 3), ") ", substring(ns, 3, 3), "-", substring(ns, 6, 4))
} else {
    concat("ERROR: Expected 10 digits, got ", length(ns))
}

Complete Working Example

The following Python script demonstrates how to programmatically create a minimal Architect flow containing this formatting logic. This ensures the syntax is valid and deployable via API.

import os
import json
from purecloudplatformclientv2 import (
    Configuration,
    ApiClient,
    ArchitectApi,
    Flow,
    FlowDocument,
    FlowAction,
    SetDataAction,
    DataNode,
    Expression
)

def create_phone_formatting_flow(api_client: ApiClient) -> str:
    """
    Creates a new Architect flow that formats a phone number.
    Returns the ID of the created flow.
    """
    architect_api = ArchitectApi(api_client)

    # 1. Define the Flow Document
    flow_doc = FlowDocument(
        name="Phone Number Formatter",
        description="Converts E.164 +1XXXXXXXXXX to (XXX) XXX-XXXX",
        type="call",
        entry_point={"action": "Start"}
    )

    # 2. Define the Start Action
    start_action = FlowAction(
        id="Start",
        type="start"
    )

    # 3. Define the Set Data Action with the Formatting Expression
    # The expression assumes the input is available in a data node named 'inputPhone'
    # In a real call flow, this might come from 'contact.attributes.phone' or similar.
    
    formatting_expression = """
    let raw = inputData.inputPhone;
    let ns = if (startsWith(raw, "+1")) { substring(raw, 2) } else { raw };
    if (length(ns) == 10) {
        concat("(", substring(ns, 0, 3), ") ", substring(ns, 3, 3), "-", substring(ns, 6, 4))
    } else {
        concat("ERROR: Invalid length ", length(ns))
    }
    """

    set_data_action = FlowAction(
        id="FormatPhone",
        type="set-data",
        action=SetDataAction(
            nodes=[
                DataNode(
                    name="formattedPhone",
                    value=Expression(
                        expression=formatting_expression
                    )
                )
            ]
        )
    )

    # 4. Define the End Action
    end_action = FlowAction(
        id="End",
        type="end"
    )

    # 5. Link the Actions
    start_action.next_action = "FormatPhone"
    set_data_action.next_action = "End"

    # 6. Assemble the Flow
    flow = Flow(
        name="Phone Number Formatter",
        description="Converts E.164 +1XXXXXXXXXX to (XXX) XXX-XXXX",
        type="call",
        entry_point={"action": "Start"},
        actions=[start_action, set_data_action, end_action]
    )

    try:
        # 7. Post the Flow to Genesys Cloud
        response = architect_api.post_architect_flow(body=flow)
        print(f"Flow created successfully. ID: {response.id}")
        return response.id
    except Exception as e:
        print(f"Error creating flow: {e}")
        raise

# Execute the function
if __name__ == "__main__":
    api_client = get_purecloud_api_client()
    flow_id = create_phone_formatting_flow(api_client)

Expected Response:
A 201 Created status with a JSON body containing the new flow’s id, version, and self URI.

Common Errors & Debugging

Error: Invalid expression: Unexpected token 'let'

What causes it:
Older versions of Genesys Cloud Architect or specific configuration settings may not support ES6+ syntax like let or const. The engine may default to strict JavaScript 1.7 or earlier.

How to fix it:
Replace let with var or inline the variables directly into the expression to avoid variable declaration entirely.

Corrected Expression (Legacy Compatible):

if (length(if (startsWith(inputData.inputPhone, "+1")) { substring(inputData.inputPhone, 2) } else { inputData.inputPhone }) == 10) {
    let ns = if (startsWith(inputData.inputPhone, "+1")) { substring(inputData.inputPhone, 2) } else { inputData.inputPhone };
    concat("(", substring(ns, 0, 3), ") ", substring(ns, 3, 3), "-", substring(ns, 6, 4))
} else {
    "Invalid"
}

Note: Even in legacy modes, simple variable assignment var ns = ... is often supported. If not, inline the logic as shown above, though it becomes less readable.

Error: TypeError: substring is not a function

What causes it:
The input data node inputData.inputPhone is null, undefined, or an integer type rather than a string. The substring method only exists on String objects.

How to fix it:
Cast the input to a string explicitly using toString() or ensure the data type in the previous action is set to String.

Corrected Expression:

let raw = toString(inputData.inputPhone);
let ns = if (startsWith(raw, "+1")) { substring(raw, 2) } else { raw };
if (length(ns) == 10) {
    concat("(", substring(ns, 0, 3), ") ", substring(ns, 3, 3), "-", substring(ns, 6, 4))
} else {
    "Invalid"
}

Error: 429 Too Many Requests

What causes it:
If you are testing this flow creation via API repeatedly in a loop, you may hit the rate limit for the POST /api/v2/architect/flows endpoint.

How to fix it:
Implement exponential backoff in your Python script.

Code Fix:

import time

def post_with_retry(api_call, max_retries=3):
    for attempt in range(max_retries):
        try:
            return api_call()
        except Exception as e:
            if "429" in str(e) or "rate limit" in str(e).lower():
                wait_time = 2 ** attempt
                print(f"Rate limited. Waiting {wait_time} seconds...")
                time.sleep(wait_time)
            else:
                raise e
    raise Exception("Max retries exceeded")

Official References

• Genesys Cloud Architect Expression Functions
• Architect API Documentation
• Python SDK Reference