Disable cache TTL by default

The current cache TTL default is 30 minutes, which is relatively short
and could easily lead to hiccups if there is a lull in data, a schema is
removed from the cache and Daffodil needs to recompile it when data
starts flowing again.

To avoid these hiccups, this changes the default to 0 seconds, which
means to never remove schemas from the cache. In most cases, if a user
uses a schema once they are probably going to use it again, so this
avoids recompilations that could lead to unexpected latencies.

nifi-daffodil-processors/src/main/java/com/owlcyberdefense/nifi/processors/AbstractDaffodilProcessor.java

@@ -138,9 +138,9 @@ public abstract class AbstractDaffodilProcessor extends AbstractProcessor {
     public static final PropertyDescriptor CACHE_TTL_AFTER_LAST_ACCESS = new PropertyDescriptor.Builder()
             .name("cache-ttl-after-last-access")
             .displayName("Cache TTL After Last Access")
-            .description("The cache TTL (time-to-live) or how long to keep compiled DFDL schemas in the cache after last access.")
+            .description("Defines how long keep unused compiled DFDL schemas in the cache before removing them to free memory. Defaults to '0 seconds' which means to never remove cached schemas.")
             .required(true)
-            .defaultValue("30 mins")
+            .defaultValue("0 seconds")
             .addValidator(StandardValidators.TIME_PERIOD_VALIDATOR)
             .build();
 

nifi-daffodil-processors/src/main/resources/docs/com.owlcyberdefense.nifi.processors.DaffodilParse/additionalDetails.html

@@ -139,9 +139,8 @@ <h2>Compiled DFDL Schema Cache</h2>
             Cached compiled DFDL schemas that go unused for a specified amount of time are removed from the cache to
             save memory. This time is defind by the <tt>Cache TTL after last access</tt> property, with the format of
             <tt>&lt;duration&gt; &lt;time_unit&gt;</tt>, where <tt>&lt;duration&gt;</tt> is a non-negative integer and
-            <tt>&lt;time_unit&gt;</tt> is a supported unit of time, such as nanos, millis, secs, mins, hrs, days. If set
-            to zero (e.g. "0 seconds"), cached compiled DFDL schemas are never removed from the cache. The default value
-            is 30 minutes.
+            <tt>&lt;time_unit&gt;</tt> is a supported unit of time, such as nanos, millis, secs, mins, hrs, days. The
+            default is "0 seconds", which means compiled DFDL schemas are never removed from the cache.
             </p>
             <p>
             For example, if a schema is used occasionally (once a day perhaps), then set this to <tt>24 hours</tt> to

nifi-daffodil-processors/src/main/resources/docs/com.owlcyberdefense.nifi.processors.DaffodilUnparse/additionalDetails.html

@@ -140,9 +140,8 @@ <h2>Compiled DFDL Schema Cache</h2>
             Cached compiled DFDL schemas that go unused for a specified amount of time are removed from the cache to
             save memory. This time is defind by the <tt>Cache TTL after last access</tt> property, with the format of
             <tt>&lt;duration&gt; &lt;time_unit&gt;</tt>, where <tt>&lt;duration&gt;</tt> is a non-negative integer and
-            <tt>&lt;time_unit&gt;</tt> is a supported unit of time, such as nanos, millis, secs, mins, hrs, days. If set
-            to zero (e.g. "0 seconds"), cached compiled DFDL schemas are never removed from the cache. The default value
-            is 30 minutes.
+            <tt>&lt;time_unit&gt;</tt> is a supported unit of time, such as nanos, millis, secs, mins, hrs, days. The
+            default is "0 seconds", which means compiled DFDL schemas are never removed from the cache.
             </p>
             <p>
             For example, if a schema is used occasionally (once a day perhaps), then set this to <tt>24 hours</tt> to