Can't catch System.ProcedureException thrown by System.requestVersion()

Question

I'm trying to write a simple method to extract the package version (using System.requestVersion()) and convert it to a string. The documentation for that method indicates that it will throw an exception if called from an unmanaged package. I've since found that it's throwing a System.ProcedureException.

But I can't figure out how to either:

• Determine if I'm in a managed package before trying to call the method.
• Catch the exception so I can return null to the caller.

The code below throws a System.ProcedureException: Method is not supported from an unmanaged namespace on the line calling System.requestVersion() but it isn't caught by the catch block for some reason.

public static String packageVersion()
{
    try
    {
        System.Version v = System.requestVersion();
        String versionString = v.major() + '.' + v.minor();
        if (v.patch() != null)
        {
            versionString += '.' + v.patch();
        }
        return versionString;
    }
    catch (Exception e) { /* ignore exceptions and return null */ }

    return null;
}

I've tried both catching all exceptions (shown above) and just catching System.ProcedureExceptions. Both fail to catch.

Looking for help with either of the bullet points at the top of the question -- code to know if it's safe to call, or a way to catch the exception.

Answer 1

It looks like System.ProcedureException is yet another uncatchable exception. I think your only option here is to avoid having that exception thrown.

You can detect if you're in an unmanaged context with some careful use of the UserInfo. isCurrentUserLicensed method. A careful read of the docs shows it throws a System.TypeException if the namespace passed is not installed in the current org, so you could make a method that detects an unmanaged context and avoids the call to requestVersion():

public static boolean isManaged(){
    boolean result;
    try{
        UserInfo.isCurrentUserLicensed('your_namespace');
        result = true;
    }catch(System.TypeException e){
        result = false;
    }
    return result;  
}

Since you only care if the package is managed, not if the user is actually licensed, you ignore the return value of isCurrentUserLicensed and only check if it throws a TypeException here.

Answer 2

    /*
 * Returns true for Managed package
 */
public static Boolean isManaged() {
    //null for unmanaged package
    if (getNameSpacePrefix() == null) {
        return false;
    } else {
        return true;
    }
}
/*
 * Returns namespacePrefix.
 * null for unmanaged package
 * <namespace name> for managed package in PROD
 */
public static String getNameSpacePrefix() {

    Map<String, Schema.SObjectType> gd = Schema.getGlobalDescribe(); 
    Set<String> gdKeys = new Set<String>();
    gdKeys = gd.keySet();
    integer indexOfToken = -1;
    // Token Sobject Name, this can be any Custom Sobject name from your product.Replace CustomObjectName with ur custom object name
    String TOKEN_SOBJECT_NAME = '__CustomObjectName__c';
    // This variable will have the namespace prefix
    String namespacePrefix = null;
    for (String sobjName: gdKeys) {
            System.debug('sobjName:'+sobjName);
        if (sobjName != null) {
            // Try matching each Sobject Name with the TOKEN Sobject
                indexOfToken = sobjName.indexOf(TOKEN_SOBJECT_NAME);
            }

        if (indexOfToken != -1) {
            // If match is success, then substring the namespace prefix
            namespacePrefix = sobjName.substring(0, indexOfToken);
            break;
        }

    }
    System.debug('namespacePrefix:'+namespacePrefix);
    return namespacePrefix;

}

Vijay