Name
global.SNMPResponse
Description
Wraps an SNMP payload response instance with methods to safely and easily retrieve SNMP singleton fields or tables.
Script
// Discovery class
/**
* Wraps an SNMP payload response instance with methods to safely and easily retrieve SNMP singleton fields or tables.
*
* Tom Dilatush tom.dilatush@service-now.com
*/
var SNMPResponse = Class.create();
SNMPResponse.prototype = {
/*
* Initializes a new instance of this class from the given payload.
*/
initialize: function(result) {
this.snmp = result.snmp;
if (!this.snmp)
this.snmp = result.result.snmp;
this.map = {};
this.normalize(this.snmp);
this.buildIndex(this.snmp, '', '');
this.buildReferences();
},
/*
* Resolve SNMP tables into hashmaps and OID values into primitives. All SNMP numeric types convert to a JavaScript
* number. An SNMP null type converts to a JavaScript null. An SNMP IP Address value converts to a Java IPAddressV4
* instance. All other values convert to a JavaScript string.
*/
normalize: function(cur) {
// what's in this thing?
for (var prop_name in cur) {
// if it's an attribute, ignore it...
if (prop_name.substring(0, 1) == '@' || prop_name.substring(0, 1) == '#')
continue;
var prop = cur[prop_name];
if (JSUtil.nil(prop))
continue;
var prop_type = JSUtil.type_of(prop);
// if this is a leaf value, it will have a type; convert it...
var oid_type = prop['@type']
if (oid_type) {
var oid_numeric = (oid_type == 'SnmpCounter32') || (oid_type == 'SnmpCounter64') ||
(oid_type == 'SnmpGauge32');
oid_numeric = oid_numeric || (oid_type == 'SnmpInt32') || (oid_type == 'SnmpUInt32') ||
(oid_type == 'SnmpTimeTicks');
var oid_null = (oid_type == 'SnmpNull');
var oid_ip = (oid_type == 'SnmpIPAddress');
var oid_oid = (oid_type == 'SnmpObjectId');
if (oid_numeric)
cur[prop_name] = JSUtil.has(prop['#text']) ? parseInt(prop['#text']) : 0;
else if (oid_oid) {
var oid_txt = JSUtil.has(prop['#text']) ? '' + prop['#text'] : null;
cur[prop_name] = (JSUtil.notNil(oid_txt) && oid_txt.charAt(0) == '.') ? oid_txt.substr(1) : oid_txt;
} else if (oid_null)
cur[prop_name] = null;
else if (oid_ip)
cur[prop_name] = JSUtil.has(prop['#text']) ?
SncIPAddressV4.getIPAddressV4Instance(prop['#text']) :
null;
else
cur[prop_name] = JSUtil.has(prop['#text']) ? '' + prop['#text'] : null;
continue;
}
// ah, but is this a table?
var index = prop['@instance'];
if (index || (prop instanceof Array)) {
// yup, we've got a table entry; transform it...
var entries = g_array_util.ensureArray(prop);
var tm = new SNMPTable();
for (var i = 0; i < entries.length; i++) {
var entry = entries[i];
var instance = entry['@instance'].substring(1); // lose the leading period...
tm[instance] = entry;
this.normalize(entry);
}
cur[prop_name] = tm;
continue;
}
// nope, we must have a container, so recursively explore it...
this.normalize(prop);
}
},
/*
* Builds references to actual instances for all identified indexes (in the discovery_snmp_ref table) that can be
* resolved.
*/
buildReferences: function() {
// iterate through all the references we know how to map to table entries...
var gr = new GlideRecord('discovery_snmp_ref');
gr.addActiveQuery();
gr.orderBy('order');
gr.query();
while (gr.next()) {
var ref = '' + gr.getValue('reference');
var ent = '' + gr.getValue('entry');
var ent_obj = this.getOIDObj(ent);
var ref_last_dot = ref.lastIndexOf('.');
var ref_base = ref.substring(0, ref_last_dot);
var ref_leaf = ref.substring(ref_last_dot + 1);
var refs = this.getAmbiguousOIDs(ref_base, ref_leaf);
if (JSUtil.nil(ent_obj))
continue;
// map to specific entries...
for (var i = 0; i < refs.length; i++) {
var entry = refs[i];
var refers_to = ent_obj[entry[ref_leaf]];
if (JSUtil.nil(refers_to))
refers_to = null;
entry[ref_leaf + '_'] = refers_to;
}
}
},
/*
* Return an array of OIDs that match the given ref_base and which have a defined, non-null ref_leaf. Note that
* the last character of ref_base may be a question mark; in that case, if the parent node is a table then all
* table entries are returned.
*/
getAmbiguousOIDs: function(ref_base, ref_leaf) {
var result = [];
// is this an ambiguous entry?
if (ref_base.substr(-1) == '?') {
var table = this.getOIDObj(ref_base.substr(0, ref_base.length - 2));
for (var ent_name in table) {
var ent = table[ent_name];
if (!ent)
continue;
var leaf = ent[ref_leaf];
if (JSUtil.nil(leaf))
continue;
result.push(ent);
}
}
// nope, so treat it as a non-table entry...
var ent = this.getOIDObj(ref_base);
if (ent)
result.push(ent);
return result;
},
/*
* Builds an index to all SNMP entities in our object. Note that it does NOT index the fields within table entries
* (though it does index the table itself).
*/
buildIndex: function(cur, name, ext_name) {
// what's in this thing?
for (var prop_name in cur) {
// if it's an attribute, ignore it...
if (prop_name.substring(0, 1) == '@' || prop_name.substring(0, 1) == '#')
continue;
var prop = cur[prop_name];
var prop_type = JSUtil.type_of(prop);
// add this fellow to our index...
var index = ext_name + ((ext_name == '') ? '' : '.') + prop_name;
this.map[index] = prop;
// if this property is a table, a primitive, or an IPAddressV4, we're done...
if ((typeof prop != 'object') || (prop instanceof SNMPTable) || (JSUtil.instance_of(prop,
'com.snc.commons.networks.IPAddressV4')))
continue;
else // nope, we've got something else; recursively explore it...
this.buildIndex(prop, prop_name, ext_name + ((ext_name == '') ? '' : '.') + prop_name);
}
},
/*
* Returns the text contained in the OID object with the given MIB name. Returns null if the object could not be
* found, or if it has no text.
*/
getOIDText: function(name) {
var oid = this.getOIDObj(name);
if (JSUtil.nil(oid))
return null;
return '' + oid;
},
/*
* Returns the integer contained in the OID object with the given MID name, or zero if the object could not be
* found or is empty.
*/
getOIDInt: function(name) {
var result = this.getOIDText(name);
return JSUtil.nil(result) ? 0 : result - 0;
},
/*
* Returns a hashmap of table entries under the given parent MIB name, with the given entry MIB names. Returns
* null if the parent does not exist.
*/
getOIDTable: function(parent_name, entry_name) {
var pn = parent_name;
if (entry_name)
pn += '.' + entry_name;
return this.getOIDObj(pn);
},
/*
* Retrieve the OID object with the given MIB name from the response. Returns null if the object could not be
* found, or if any table entries are encountered while walking down the named elements. Note that this method
* does not work with numeric OID strings, only MIB names.
*/
getOIDObj: function(name) {
return this.map[name];
},
type: "SNMPResponse"
};Sys ID
83f9a33a0ab30153004187736f3a6d34