Amazon DynamoDB からのクエリで実証的にテストと測定を行う

package example;

import com.amazonaws.Request;
import com.amazonaws.Response;
import com.amazonaws.metrics.RequestMetricCollector;

import java.util.Timer;
import java.util.TimerTask;
import java.util.concurrent.ConcurrentHashMap;
import java.util.regex.Pattern;

public class DDBQueryLogger extends RequestMetricCollector {

    private static final long TIMER_DELAY = 0L;
    private static final long TIMER_PERIOD = 100; // 5 * 60 * 1000;
    private static final int MAX_HASH_MAP_SIZE = 10000;
    protected static final ConcurrentHashMap<String, DDBQueryInfo> ddbQueryInfos = new ConcurrentHashMap<>();

    // These regular expressions strip out all query specific values.This helps
    // us “standardize” the textual representation of the query.For example,
    // “uuid={S:123}” would become “uuid={S:}”.This makes it possible to group
    // classes of queries together.
    private static final Pattern N = Pattern.compile("(?<=N:)(.*?)(?=,)");
    private static final Pattern S = Pattern.compile("(?<=S:)(.*?)(?=,)");

    private static final TimerTask emitLogTask = new TimerTask() {
        /**
         * Loop over all standardized DDB queries in memory for this host and emit our DDBQueryInfo object.
         */
        public void run() {
            for (final DDBQueryInfo ddbQueryInfo : ddbQueryInfos.values()) {
                System.out.println("PerformanceMetrics: " + ddbQueryInfo.toString());
            }
        }
    };

    private static final Timer timer = new Timer("Timer");

    static {
        timer.scheduleAtFixedRate(emitLogTask, TIMER_DELAY, TIMER_PERIOD);
        System.out.println("Timer started.");
    }

    @Override
    public void collectMetrics(Request<?> request, Response<?> response) {
        if (request == null || request.getOriginalRequest() == null) {
            return;
        }

        // Preventing out-of-memory errors.If you are standardizing queries correctly, you should never come close to this.
        if (ddbQueryInfos.keySet().size() > MAX_HASH_MAP_SIZE) {
            System.out.println("DDBQueryLogger in-memory data structure is too big.Standardized queries are broken.");
            return;
        }

        final String ddbQuery = standardizeQuery(request.getOriginalRequest().toString());

        final DDBQueryInfo infoOld = ddbQueryInfos.get(ddbQuery);

        final DDBQueryInfo infoNew = new DDBQueryInfo();
        infoNew.setExampleQuery(request.getOriginalRequest().toString());
        infoNew.setStandardizedQuery(ddbQuery);

        if (infoOld != null) {
            infoNew.getCount().set(infoOld.getCount().incrementAndGet());
        } else {
            infoNew.getCount().set(1L);
        }

        ddbQueryInfos.put(ddbQuery, infoNew);
    }

    /**
     * Take a DDB query (as a string) and remove all values that make it unique.
     * @param query toString() of the "original request" from the AWS SDK.
     * @return Standardized DDB query.
     */
    private String standardizeQuery(final String query) {
        return N.matcher(S.matcher(query).replaceAll("")).replaceAll("");
    }

}

package example;

import java.util.concurrent.atomic.AtomicLong;

public class DDBQueryInfo {
    private AtomicLong count;
    private String exampleQuery;
    private String standardizedQuery;

    public AtomicLong getCount() { return count; }
    public void setCount(AtomicLong count) { this.count = count; }

    public String getExampleQuery() { return exampleQuery; }
    public void setExampleQuery(String exampleQuery) { this.exampleQuery = exampleQuery; }

    public String getStandardizedQuery() { return standardizedQuery; }
    public void setStandardizedQuery(String standardizedQuery) { this. standardizedQuery = standardizedQuery; }

    public DDBQueryInfo() {
        this.count = new AtomicLong();
    }

    /**
     * "@@" should help us tokenize a log entry.
     * @return A parsable string representing the object state.
     */
    @Override
    public String toString() {
        return String.format("@@ %s @@ %s @@ %s", count, exampleQuery, standardizedQuery);
    }
}

package example;

import com.amazonaws.AmazonServiceException;
import com.amazonaws.services.dynamodbv2.AmazonDynamoDB;
import com.amazonaws.services.dynamodbv2.AmazonDynamoDBClientBuilder;
import com.amazonaws.services.dynamodbv2.model.AttributeValue;
import com.amazonaws.services.dynamodbv2.model.GetItemRequest;
import com.amazonaws.services.lambda.runtime.Context; 
import com.amazonaws.services.lambda.runtime.RequestHandler;

import java.util.HashMap;
import java.util.Map;
import java.util.Set;

public class LogTest implements RequestHandler<Integer, String> {

    public String handleRequest(Integer myCount, Context context) {
    	for (int i = 0; i < 5; i++) {
    		getItem();
    	}

        return "Log test done.";
    }

    public void getItem() {
        HashMap<String, AttributeValue> key = new HashMap<>();

        key.put("uuid", new AttributeValue("73bed7db-55d8-4ecc-b516-ddb0672bc31a"));

        GetItemRequest request = new GetItemRequest()
            .withKey(key)
            .withTableName("LogTest");

        // Make sure that your DynamoDB client references the DDBQueryLogger class.
        // You might consider turning it on/off with a feature flag.
        final AmazonDynamoDB ddb = AmazonDynamoDBClientBuilder
        	.standard()
        	.withMetricsCollector(new DDBQueryLogger())
        	.build();

        try {
            Map<String, AttributeValue> item = ddb.getItem(request).getItem();
        } catch (AmazonServiceException e) {
            System.err.println(e.getErrorMessage());
        }
    }

}

apply plugin: 'java'

repositories {
  mavenCentral()
}

dependencies {
    compile (
        'com.amazonaws:aws-lambda-java-core:1.1.0',
        'com.amazonaws:aws-lambda-java-events:1.1.0',
        'com.fasterxml.jackson.core:jackson-core:2.9.8',
        'com.amazonaws:aws-java-sdk-dynamodb'
    )
}

task buildZip(type: Zip) {
    from compileJava
    from processResources              
    into('lib') {
        from configurations.compileClasspath
    }           
}

build.dependsOn buildZip

START RequestId: 5e22204c-d91c-4899-924d-abaef69589f4 Version: $LATEST
Timer started.
PerformanceMetrics: @@ 1 @@ {TableName: LogTest,Key: {uuid={S: 73bed7db-55d8-4ecc-b516-ddb0672bc31a,}},} @@ {TableName: LogTest,Key: {uuid={S:,}},}
PerformanceMetrics: @@ 1 @@ {TableName: LogTest,Key: {uuid={S: 73bed7db-55d8-4ecc-b516-ddb0672bc31a,}},} @@ {TableName: LogTest,Key: {uuid={S:,}},}
PerformanceMetrics: @@ 1 @@ {TableName: LogTest,Key: {uuid={S: 73bed7db-55d8-4ecc-b516-ddb0672bc31a,}},} @@ {TableName: LogTest,Key: {uuid={S:,}},}
PerformanceMetrics: @@ 1 @@ {TableName: LogTest,Key: {uuid={S: 73bed7db-55d8-4ecc-b516-ddb0672bc31a,}},} @@ {TableName: LogTest,Key: {uuid={S:,}},}
PerformanceMetrics: @@ 2 @@ {TableName: LogTest,Key: {uuid={S: 73bed7db-55d8-4ecc-b516-ddb0672bc31a,}},} @@ {TableName: LogTest,Key: {uuid={S:,}},}
PerformanceMetrics: @@ 2 @@ {TableName: LogTest,Key: {uuid={S: 73bed7db-55d8-4ecc-b516-ddb0672bc31a,}},} @@ {TableName: LogTest,Key: {uuid={S:,}},}
PerformanceMetrics: @@ 4 @@ {TableName: LogTest,Key: {uuid={S: 73bed7db-55d8-4ecc-b516-ddb0672bc31a,}},} @@ {TableName: LogTest,Key: {uuid={S:,}},}
PerformanceMetrics: @@ 4 @@ {TableName: LogTest,Key: {uuid={S: 73bed7db-55d8-4ecc-b516-ddb0672bc31a,}},} @@ {TableName: LogTest,Key: {uuid={S:,}},}
END RequestId: 5e22204c-d91c-4899-924d-abaef69589f4
REPORT RequestId: 5e22204c-d91c-4899-924d-abaef69589f4	Duration: 9607.21 ms	Billed Duration: 9700 ms 	Memory Size: 512 MB	Max Memory Used: 139 MB