Zipping and password protect file using camel - apache-camel

Question

I have been trying to zip multiple csv file in my route. I have been successfully able to do that.
I am using spring to do the same.
Now the new requirement is to password protect them. Following is the aggregation strategy I have used. How to achieve this?
<route autoStartup="false" routePolicyRef="routeTwoTimer" startupOrder="2" id="zippingFileRoute">
<from uri="{{to.file.processed1}}"/>
<choice id="csvZipFile">
<when>
<simple>$simple{header.CamelFileName} regex '^.*(csv|CSV)$'</simple>
<aggregate strategyRef="zipAggregationStrategy" completionFromBatchConsumer="true" eagerCheckCompletion="true">
<correlationExpression>
<constant>true</constant>
</correlationExpression>
<to uri="{{to.file.processed2}}"/>
</aggregate>
</when>
</choice>
</route>

Answer 1

As pointed in comments, Java API is a bit limited in encrypting ZIP files. Apache Camel ZipAggregationStrategy is using ZipOutputStream, so there is this limitation too. You can implement custom Aggregator using any other library, which allows encryption of Zip files. For example Zip4j
Add Maven dependency
<dependency>
<groupId>net.lingala.zip4j</groupId>
<artifactId>zip4j</artifactId>
<version>1.3.2</version>
</dependency>
Implement custom Aggregator
import net.lingala.zip4j.core.ZipFile;
//next few imports. I have added this only to take correct ZipFile class, not the JDK one
public class PasswordZipAggregationStrategy implements AggregationStrategy {
public static final String ZIP_PASSWORD_HEADER = "PasswordZipAggregationStrategy.ZipPassword";
#Override
public Exchange aggregate(Exchange oldExchange, Exchange newExchange){
try {
if (newExchange == null) {
return oldExchange;
}
return aggregateUnchecked(oldExchange,newExchange);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
private Exchange aggregateUnchecked(Exchange oldExchange, Exchange newExchange) throws Exception{
ZipFile zipFile;
String password;
if (oldExchange == null) { // first
password = newExchange.getIn().getHeader(ZIP_PASSWORD_HEADER, String.class);
zipFile = new ZipFile(newExchange.getExchangeId()+".zip");
File toDelete = new File(zipFile.getFile().getPath());
newExchange.addOnCompletion(new Synchronization() {
#Override
public void onComplete(Exchange exchange) {
toDelete.delete();
}
#Override
public void onFailure(Exchange exchange) {
}
});
} else {
password = newExchange.getIn().getHeader(ZIP_PASSWORD_HEADER, String.class);
zipFile = new ZipFile(oldExchange.getIn().getBody(File.class));
}
if (password==null){
throw new IllegalStateException("Null password given");
}
ZipParameters zipParameters = new ZipParameters();
zipParameters.setPassword(password);
zipParameters.setEncryptFiles(true);
zipParameters.setCompressionLevel(Zip4jConstants.DEFLATE_LEVEL_FAST);
zipParameters.setEncryptionMethod(Zip4jConstants.ENC_METHOD_STANDARD);
zipFile.addFile(newExchange.getIn().getBody(File.class), zipParameters);
GenericFile genericFile = FileConsumer.asGenericFile(zipFile.getFile().getParent(), zipFile.getFile(), Charset.defaultCharset().toString(), false);
genericFile.bindToExchange(newExchange);
newExchange.getIn().setBody(zipFile.getFile());
newExchange.getIn().setHeader(ZIP_PASSWORD_HEADER, password);
return newExchange;
}
}
Use it
from("file://in")
.to("log:in")
.setHeader(PasswordZipAggregationStrategy.ZIP_PASSWORD_HEADER, constant("testPassword"))
.aggregate().constant(true).completionFromBatchConsumer()
.aggregationStrategy(new PasswordZipAggregationStrategy())
.to("log:out")
.to("file://out");