Name
global.AbstractReconciler
Description
Abstract base class for reconciling newly discovered data in an XMLMemoryTable to a related list in the database.
Script
// Discovery
gs.include("PrototypeServer");
/**
* Implements the common logic and helper methods for reconciling related lists for a particular CMDB item against
* discovered information present in a MemoryTable instance. Most of this logic is very straightforward, but one bit
* may not be: the resolution of references to previously reconciled records. This feature works by collecting
* information while reconciling one related list, then passing that information on to the reconciler for another
* related list. For example, while switch partitions are being reconciled, information is gathered (in a Map instance)
* that maps an interface number for a partition to the sys_id of the partition's record in the partition table. Then
* later when the switchports are being reconciled, a reference to the switch partition that contains the switchport
* can be resolved by using this Map.
*
* author Tom Dilatush tom.dilatush@service-now.com
*/
var AbstractReconciler = Class.create();
AbstractReconciler.prototype = {
/**
* Creates a new instance of this class for the given related list, parent field name, CMDB item, and newly
* discovered data.
*
* tableName
* The table name of the related list we are reconciling to.
* parentFieldName
* The field name for the reference to the parent record.
* cmdbSysID
* The sys_id for the CMDB item that owns our related list.
* discovered
* The MemoryTable containing our newly discovered information.
*/
_initialize: function(tableName, parentFieldName, cmdbSysID, discovered) {
this.database = new GlideRecord(tableName); // GlideRecord: the related list being reconciled...
this.discovered = discovered; // MemoryTable: the data just discovered...
this.rediscovered = null; // Set: tracks those items that have been rediscovered (so we can
// figure out which discovered items are new)...
this.cmdbSysID = cmdbSysID; // String: the sys_id of the CMDB item we're related to...
this.parentFieldName = parentFieldName; // String: the name of the field containing a reference to the
// parent...
this.database.addQuery(this.parentFieldName, this.cmdbSysID);
this.database.query();
},
/**
* Reconciles the newly discovered data with the data already present in the database. Resolves references
* to previously reconciled data.
*/
process: function() {
// some setup...
this.rediscovered = new Packages.java.util.HashSet();
var rField = this.getReconcilationField();
if (!this.discovered.index(rField))
gs.log('WARNING: At least one duplicate key in reconcilation: ' + this.type);
this.setup();
// walk through each record we already have in the database...
while (this.database.next()) {
// read in what's currently in the database for this record...
this.readDatabaseFields();
// does the same item exist in the newly discovered data?
var rKey = this.getReconcilationKey();
if (this.discovered.indexMoveTo(rKey)) {
// yes, we found the same item, so read the data we discovered and see if it's valid...
if (!this.readDiscovered())
continue;
// we got valid data, so resolve any reference fields, mark it as rediscovered, and track it...
this.resolveReferenceFields();
this.rediscovered.add('' + rKey);
this.track(this.database.getValue('sys_id'));
// if the data we discovered is different than what we already knew, update the database...
if (this.hasChanged()) {
this.setDatabaseFields();
this.markPresent();
this.database.update();
}
} else { // the item in the database isn't in the discovered data, so mark the database record as absent...
this.markAbsent();
this.database.update();
}
}
// iterate through any discovered records that were not marked as rediscovered...
var it = this.discovered.iteratorRemaining(this.rediscovered);
while (it.hasNext()) {
// read the data from the discovered record, and see if it was valid...
it.next();
if (!this.readDiscovered())
continue;
// we got valid data, so resolve any reference fields...
this.resolveReferenceFields();
// insert a new record in the database for this item and track it...
this.database.initialize();
this.setDatabaseFields();
this.database.setValue(this.parentFieldName, this.cmdbSysID);
this.markPresent();
this.track(this.database.insert());
}
},
/**
* Optional method, overridden in concrete subclasses that need special setup.
*/
setup: function() {},
/**
* Optional method, overridden in concrete subclasses that need to track reference resolution information for the
* current updated or inserted database record. Typically this method adds a map entry relating some discoverable
* information to the sys_id of the current database record, but this behavior is not mandatory.
*
* sysID
* The sys_id of the current database record.
*/
track: function(sysID) {},
/**
* Optional method, overridden in concrete subclasses that need to resolve reference fields. This method is invoked
* after valid discovered data is read. Generally implementations will use some of this discovered data as a key
* into a map (passed into the concrete reconciler class when it was instantiated) that will return the sys_id of
* the database record holding the referenced information. However, implementations are not required to use this
* approach.
*/
resolveReferenceFields: function() {},
/**
* Read the fields in the current database record into instance member fields.
* Mandatory method, must be overridden in all concrete subclasses.
*/
readDatabaseFields: function() {},
/**
* Read the current memory table record of newly discovered data and check its validity.
* Mandatory method, must be overridden in all concrete subclasses.
*
* return
* A boolean, true if the data read is valid.
*/
readDiscovered: function() {},
/**
* Returns the name of the column in the memory table of discovered data that will be used as the key to find
* rediscovered records. The memory table will be indexed on this column.
* Mandatory method, must be overridden in all concrete subclasses.
*
* return
* The column name.
*/
getReconcilationKey: function() {},
/**
* Returns the string value of the field to be used as a key to look up a record in the newly discovered data. This
* value will be used to attempt to find a record in the discovered data, using the column returned by the
* getReconciliationKey() method.
* Mandatory method, must be overridden in all concrete subclasses.
*
* return
* The String value to use as a key into the discovered data.
*/
getReconcilationField: function() {},
/**
* Returns true if the newly discovered data is different than the data already in the database for this item. This
* method is only invoked for items that have been rediscovered.
* Mandatory method, must be overridden in all concrete subclasses.
*
* return
* A boolean, true if the data has changed.
*/
hasChanged: function() {},
/**
* Sets the database fields for the current record to the valuees in the newly discovered information. This method
* is invoked both for new database records and for existing database records when the discovered data has changed.
* Mandatory method, must be overridden in all concrete subclasses.
*/
setDatabaseFields: function() {},
/**
* CIs are marked as absent by setting the install status to "Absent"; other tables are marked by setting the
* (presumed present) field "absent" to true.
*/
markAbsent: function() {
if (this.isCI())
this.database.setValue('install_status', 100); // set to "Absent"...
else
this.database.setValue('absent', true);
},
/**
* CIs are marked as present by setting the install status to "Installed"; other tables are marked by setting the
* (presumed present) field "absent" to false.
*/
markPresent: function() {
if (this.isCI())
this.database.setValue('install_status', 1); // set to "Installed"...
else
this.database.setValue('absent', false);
},
isCI: function() {
var base = '' + GlideDBObjectManager.get().getAbsoluteBase0(this.database.getTableName());
return 'cmdb_ci' == base;
},
//===============================================================================================================
// The following methods are all helper methods; their main purpose is to provide simpler, cleaner syntax in the
// concrete subclasses.
//===============================================================================================================
areEqual: function(a, b) {
if ((a instanceof Object) || (b instanceof Object))
return GlideObjectUtil.areEqual(a, b);
else
return a == b;
},
areNotEqual: function(a, b) {
return !this.areEqual(a, b);
},
getDsMAC: function(fieldName) {
return SncMACAddress.getMACAddressInstance(this.discovered.getValue(fieldName));
},
getDsIP: function(fieldName) {
return SncIPAddressV4.getIPAddressV4Instance(this.discovered.getValue(
fieldName));
},
getDsNetmask: function(fieldName) {
return SncIPNetmaskV4.getIPNetmaskV4Instance(this.discovered.getValue(
fieldName));
},
getDsNetwork: function(fieldName) {
return SncIPNetworkV4.getIPNetworkInstance(this.discovered.getValue(fieldName));
},
getDsBoolean: function(fieldName) {
return 'true' == this.discovered.getValue(fieldName);
},
getDsInt: function(fieldName) {
return this.discovered.getValueInt(fieldName);
},
getDsFloat: function(fieldName) {
return this.discovered.getValueDouble(fieldName);
},
getDsString: function(fieldName) {
return this.discovered.getValue(fieldName);
},
getMAC: function(fieldName) {
return SncMACAddress.getMACAddressInstance(this.database.getValue(fieldName));
},
getIP: function(fieldName) {
return SncIPAddressV4.getIPAddressV4Instance(this.database.getValue(fieldName));
},
getNetmask: function(fieldName) {
return SncIPNetmaskV4.getIPNetmaskV4Instance(this.database.getValue(fieldName));
},
getNetwork: function(fieldName) {
return SncIPNetworkV4.getIPNetworkInstance(this.database.getValue(fieldName));
},
getBoolean: function(fieldName) {
return true && this.database.getValue(fieldName);
},
getInt: function(fieldName) {
return this.database.getValue(fieldName) - 0;
},
getFloat: function(fieldName) {
return this.database.getValue(fieldName) - 0.0;
},
getString: function(fieldName) {
return this.database.getValue(fieldName);
},
set: function(fieldName, value) {
var val = (value == null) ? '' : value;
if (val instanceof Object)
val = val.toString();
this.database.setValue(fieldName, val);
},
type: 'AbstractReconciler'
};Sys ID
a8cfae6f0ab3015600584bcd5ca1e5c3