Code Explainer

API Response Validation for Reference Numbers

This code snippet demonstrates handling an API response in Java, validating a reference number against a specific format using regular expressions, and updating a response map with success or error messages based on the validation result.

Prompt

entityMap = crmAPIRequest.toMap().get("record");
referenceField= entityMap.get("Reference_Number"); // Reference_Number is the API name for "Reference number" field.
response = Map();
if(referenceField.matches("[A-Z]{3}-[0-9]{10}")) {
      response.put('status','error');
      response.put('message', 'Invalid Reference Number');
} else {
/* If there are no errors found during validation, set the status as shown below: */
      response.put('status','success');
}

Answer

Code Explanation

The provided code snippet is written in a Java-like syntax. It demonstrates how to handle an API response, validate a reference number, and return an appropriate status and message based on the validation result.

Code Breakdown

Variable Initialization
```
entityMap = crmAPIRequest.toMap().get("record");
```
- crmAPIRequest.toMap(): Converts the crmAPIRequest object to a Map.
- .get("record"): Retrieves the value associated with the key "record" from the map, which is assigned to entityMap.
Extracting Reference Field
```
referenceField = entityMap.get("Reference_Number");
```
- Retrieves the value associated with the key "Reference_Number" in entityMap and stores it in referenceField. This represents the reference number field from the API response.
Initializing Response Map
```
response = Map();
```
- Initializes an empty map called response to store the validation results.
Validation and Response Population
```
if (referenceField.matches("[A-Z]{3}-[0-9]{10}")) {
    response.put('status', 'error');
    response.put('message', 'Invalid Reference Number');
} else {
    response.put('status', 'success');
}
```
- referenceField.matches("[A-Z]{3}-[0-9]{10}"): Checks if referenceField matches the specified regular expression pattern.
  - [A-Z]{3}: Checks for exactly three uppercase letters.
  - -: Checks for a hyphen.
  - [0-9]{10}: Checks for exactly ten digits.
- If the reference number matches the pattern, the response map is updated with 'status': 'error' and 'message': 'Invalid Reference Number'.
- If it does not match, the response map is updated with 'status': 'success'.

Key Concepts

Maps
- A Map is a collection of key-value pairs. In this code:
  - crmAPIRequest.toMap() converts an object to a map.
  - entityMap.get("Reference_Number") retrieves a value from the map.
Regular Expressions (Regex)
- Regular expressions are patterns used to match strings. The pattern [A-Z]{3}-[0-9]{10} specifies the format of a valid reference number.
Validation Logic
- Validation is performed using the matches method, which checks if the reference number adheres to the expected format.

Additional Example

To demonstrate a similar concept, consider the following Python code that achieves the same functionality:

crm_api_response = {"record": {"Reference_Number": "ABC-0123456789"}}
entity_map = crm_api_response.get("record")
reference_field = entity_map.get("Reference_Number")
response = {}

import re
if re.match(r"[A-Z]{3}-[0-9]{10}", reference_field):
    response['status'] = 'error'
    response['message'] = 'Invalid Reference Number'
else:
    response['status'] = 'success'

print(response)

Conclusion

The provided code validates a reference number from an API response against a specific format using regular expressions and updates a response map with the validation result. Understanding maps and regular expressions is crucial for grasping the logic behind this code. For further learning on related topics, consider the courses available on the Enterprise DNA Platform.