org.jumpmind.symmetric.route.ColumnMatchDataRouter Maven / Gradle / Ivy
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/*
* Licensed to JumpMind Inc under one or more contributor
* license agreements. See the NOTICE file distributed
* with this work for additional information regarding
* copyright ownership. JumpMind Inc licenses this file
* to you under the GNU Lesser General Public License (the
* "License"); you may not use this file except in compliance
* with the License.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see
*
* The value can be a constant. In the data router the value of the new data is
* always represented by a string so all comparisons are done in the format that
* SymmetricDS transmits.
*
* The column name used for the match is the upper case column name if the
* current value is being compared. The upper case column name prefixed by OLD_
* can be used if the comparison is being done of the old data.
*
* For example, if the column on a table is named STATUS you can specify that
* you want to router when STATUS=OK by specifying such for the
* router_expression. If you wanted to route when only the old value for
* STATUS=OK you would specify OLD_STATUS=OK.
*
* The value can also be one of the following expressions:
*
* - :NODE_ID
* - :EXTERNAL_ID
* - :NODE_GROUP_ID
* - :REDIRECT_NODE
* - :{column name}
*
* NODE_ID, EXTERNAL_ID, and NODE_GROUP_ID are instructions for the column
* matcher to select nodes that have a NODE_ID, EXTERNAL_ID or NODE_GROUP_ID
* that are equal to the value on the column.
*
* REDIRECT_NODE is an instruction to match the specified column to a
* registrant_external_id on registration_redirect and return the associated
* registration_node_id in the list of node id to route to. For example, if the
* 'price' table was being routed to to a region 1 node based on the store_id,
* the store_id would be the external_id of a node in the registration_redirect
* table and the router_expression for trigger entry for the 'price' table would
* be 'store_id=:REDIRECT_NODE' and the router_type would be 'column'.
*
*
*
*/
public class ColumnMatchDataRouter extends AbstractDataRouter implements IDataRouter {
private static final String NULL_VALUE = "NULL";
private IRegistrationService registrationService;
final static String EXPRESSION_KEY = String.format("%s.Expression.", ColumnMatchDataRouter.class
.getName());
public Collection routeToNodes(IRouterContext routingContext,
DataMetaData dataMetaData, Set nodes, boolean initialLoad) {
Set nodeIds = null;
List expressions = getExpressions(dataMetaData.getTriggerRouter().getRouter(), routingContext);
Map columnValues = getDataMap(dataMetaData);
if (columnValues != null) {
for (Expression e : expressions) {
String column = e.tokens[0].trim();
String value = e.tokens[1];
if (value.equalsIgnoreCase(TokenConstants.NODE_ID)) {
for (Node node : nodes) {
if (e.equals && node.getNodeId().equals(columnValues.get(column))) {
nodeIds = addNodeId(node.getNodeId(), nodeIds, nodes);
}
}
} else if (value.equalsIgnoreCase(TokenConstants.EXTERNAL_ID)) {
for (Node node : nodes) {
if (e.equals && node.getExternalId().equals(columnValues.get(column))) {
nodeIds = addNodeId(node.getNodeId(), nodeIds, nodes);
}
}
} else if (value.equalsIgnoreCase(TokenConstants.NODE_GROUP_ID)) {
for (Node node : nodes) {
if (e.equals && node.getNodeGroupId().equals(columnValues.get(column))) {
nodeIds = addNodeId(node.getNodeId(), nodeIds, nodes);
}
}
} else if (e.equals && value.equalsIgnoreCase(TokenConstants.REDIRECT_NODE)) {
Map redirectMap = getRedirectMap(routingContext);
String nodeId = redirectMap.get(columnValues.get(column));
if (nodeId != null) {
nodeIds = addNodeId(nodeId, nodeIds, nodes);
}
} else if (value.startsWith(":")) {
String firstValue = columnValues.get(column);
String secondValue = columnValues.get(value.substring(1));
if (e.equals
&& ((firstValue == null && secondValue == null) || (firstValue != null
&& secondValue != null && firstValue.equals(secondValue)))) {
nodeIds = toNodeIds(nodes, nodeIds);
} else if (!e.equals
&& ((firstValue != null && secondValue == null)
|| (firstValue == null && secondValue != null) || (firstValue != null
&& secondValue != null && !firstValue.equals(secondValue)))) {
nodeIds = toNodeIds(nodes, nodeIds);
}
} else {
if (e.equals && (value.equals(columnValues.get(column)) ||
(value.equals(NULL_VALUE) && columnValues.get(column) == null))) {
nodeIds = toNodeIds(nodes, nodeIds);
} else if (!e.equals && ((!value.equals(NULL_VALUE) && !value.equals(columnValues.get(column))) ||
(value.equals(NULL_VALUE) && columnValues.get(column) != null))) {
nodeIds = toNodeIds(nodes, nodeIds);
}
}
}
} else {
log.warn("RouterNoColumnsToMatch", dataMetaData.getData().getDataId());
}
return nodeIds;
}
/**
* Cache parsed expressions in the context to minimize the amount of parsing
* we have to do when we have lots of throughput.
*/
@SuppressWarnings("unchecked")
protected List getExpressions(Router router, IRouterContext context) {
final String KEY = EXPRESSION_KEY + router.getRouterId();
List expressions = (List) context.getContextCache().get(
KEY);
if (expressions == null) {
expressions = new ArrayList();
String routerExpression = router.getRouterExpression();
if (!StringUtils.isBlank(routerExpression)) {
context.getContextCache().put(KEY, expressions);
String[] expTokens = routerExpression.split("\r\n|\r|\n");
if (expTokens != null) {
for (String t : expTokens) {
if (!StringUtils.isBlank(t)) {
String[] tokens = null;
boolean equals = !t.contains("!=");
if (!equals) {
tokens = t.split("!=");
} else {
tokens = t.split("=");
}
if (tokens.length == 2) {
expressions.add(new Expression(equals, tokens));
} else {
log.warn("RouterIllegalColumnMatchExpression", t, routerExpression);
}
}
}
}
} else {
log.warn("RouterIllegalColumnMatchExpression", routerExpression, routerExpression);
}
}
return expressions;
}
@SuppressWarnings("unchecked")
protected Map getRedirectMap(IRouterContext ctx) {
final String CTX_CACHE_KEY = ColumnMatchDataRouter.class.getSimpleName() + "RouterMap";
Map redirectMap = (Map) ctx.getContextCache().get(
CTX_CACHE_KEY);
if (redirectMap == null) {
redirectMap = registrationService.getRegistrationRedirectMap();
ctx.getContextCache().put(CTX_CACHE_KEY, redirectMap);
}
return redirectMap;
}
public void setRegistrationService(IRegistrationService registrationService) {
this.registrationService = registrationService;
}
class Expression {
boolean equals;
String[] tokens;
public Expression(boolean equals, String[] tokens) {
this.equals = equals;
this.tokens = tokens;
}
}
}