dcache-common: add QoS Json policy objects

Motivation:

Implement version 1 of the QoS Policy/Rule engine.

Modification:

This patch adds the various JSON objects used
to define a QoS policy.

A parsing unit test is included.

Result:

The QoS policy (schema) is now defined.

Target: master
Patch: https://rb.dcache.org/r/14024/
Acked-by: Tigran

modules/common/src/main/java/org/dcache/qos/DefaultQoSDiskSpecification.java

@@ -0,0 +1,139 @@
+/*
+COPYRIGHT STATUS:
+Dec 1st 2001, Fermi National Accelerator Laboratory (FNAL) documents and
+software are sponsored by the U.S. Department of Energy under Contract No.
+DE-AC02-76CH03000. Therefore, the U.S. Government retains a  world-wide
+non-exclusive, royalty-free license to publish or reproduce these documents
+and software for U.S. Government purposes.  All documents and software
+available from this server are protected under the U.S. and Foreign
+Copyright Laws, and FNAL reserves all rights.
+
+Distribution of the software available from this server is free of
+charge subject to the user following the terms of the Fermitools
+Software Legal Information.
+
+Redistribution and/or modification of the software shall be accompanied
+by the Fermitools Software Legal Information  (including the copyright
+notice).
+
+The user is asked to feed back problems, benefits, and/or suggestions
+about the software to the Fermilab Software Providers.
+
+Neither the name of Fermilab, the  URA, nor the names of the contributors
+may be used to endorse or promote products derived from this software
+without specific prior written permission.
+
+DISCLAIMER OF LIABILITY (BSD):
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED  WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED  WARRANTIES OF MERCHANTABILITY AND FITNESS
+FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL FERMILAB,
+OR THE URA, OR THE U.S. DEPARTMENT of ENERGY, OR CONTRIBUTORS BE LIABLE
+FOR  ANY  DIRECT, INDIRECT,  INCIDENTAL, SPECIAL, EXEMPLARY, OR
+CONSEQUENTIAL DAMAGES  (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+OF SUBSTITUTE  GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY  OF
+LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT  OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE  POSSIBILITY OF SUCH DAMAGE.
+
+Liabilities of the Government:
+
+This software is provided by URA, independent from its Prime Contract
+with the U.S. Department of Energy. URA is acting independently from
+the Government and in its own private capacity and is not acting on
+behalf of the U.S. Government, nor as its contractor nor its agent.
+Correspondingly, it is understood and agreed that the U.S. Government
+has no connection to this software and in no manner whatsoever shall
+be liable for nor assume any responsibility or obligation for any claim,
+cost, or damages arising out of or resulting from the use of the software
+available from this server.
+
+Export Control:
+
+All documents and software available from this server are subject to U.S.
+export control laws.  Anyone downloading information from this server is
+obligated to secure any necessary Government licenses before exporting
+documents or software obtained from this server.
+ */
+package org.dcache.qos;
+
+import java.util.List;
+import java.util.Objects;
+
+/**
+ *  A simple disk specification.  Type may or may not be supported by the QoS verifier.
+ */
+public class DefaultQoSDiskSpecification extends QoSDiskSpecification {
+
+    private static final long serialVersionUID = -4741659925401058789L;
+
+    /**
+     *  e.g., "SSD", "Spinning"
+     */
+    private String type;
+
+    /**
+     *  Total number of copies on this medium.
+     */
+    private Integer numberOfCopies;
+
+    /**
+     *  How the copies should be partitioned across the media instances, if there
+     *  are more than one.
+     */
+    private List<String> partitionKeys;
+
+    @Override
+    public String getType() {
+        return type;
+    }
+
+    @Override
+    public Integer getNumberOfCopies() {
+        return numberOfCopies;
+    }
+
+    @Override
+    public List<String> getPartitionKeys() {
+        return partitionKeys;
+    }
+
+    public void setType(String type) {
+        this.type = type;
+    }
+
+    public void setNumberOfCopies(Integer numberOfCopies) {
+        this.numberOfCopies = numberOfCopies;
+    }
+
+    public void setPartitionKeys(List<String> partitionKeys) {
+        this.partitionKeys = partitionKeys;
+    }
+
+    public boolean equals(Object obj) {
+        if (!(obj instanceof DefaultQoSDiskSpecification)) {
+            return false;
+        }
+
+        DefaultQoSDiskSpecification other = (DefaultQoSDiskSpecification) obj;
+
+        if ((type == null && other.type != null) ||
+              type != null && !type.equals(other.type)) {
+            return false;
+        }
+
+        if ((numberOfCopies == null && other.numberOfCopies != null) ||
+              (numberOfCopies != null && numberOfCopies != other.numberOfCopies)) {
+            return false;
+        }
+
+        return (partitionKeys == null && other.partitionKeys == null) ||
+              partitionKeys != null && partitionKeys.equals(other.partitionKeys);
+    }
+
+    public int hashCode() {
+        return Objects.hash(type, numberOfCopies, partitionKeys);
+    }
+}

modules/common/src/main/java/org/dcache/qos/DefaultQoSPolicyJsonDeserializer.java

@@ -0,0 +1,148 @@
+/*
+COPYRIGHT STATUS:
+Dec 1st 2001, Fermi National Accelerator Laboratory (FNAL) documents and
+software are sponsored by the U.S. Department of Energy under Contract No.
+DE-AC02-76CH03000. Therefore, the U.S. Government retains a  world-wide
+non-exclusive, royalty-free license to publish or reproduce these documents
+and software for U.S. Government purposes.  All documents and software
+available from this server are protected under the U.S. and Foreign
+Copyright Laws, and FNAL reserves all rights.
+
+Distribution of the software available from this server is free of
+charge subject to the user following the terms of the Fermitools
+Software Legal Information.
+
+Redistribution and/or modification of the software shall be accompanied
+by the Fermitools Software Legal Information  (including the copyright
+notice).
+
+The user is asked to feed back problems, benefits, and/or suggestions
+about the software to the Fermilab Software Providers.
+
+Neither the name of Fermilab, the  URA, nor the names of the contributors
+may be used to endorse or promote products derived from this software
+without specific prior written permission.
+
+DISCLAIMER OF LIABILITY (BSD):
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED  WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED  WARRANTIES OF MERCHANTABILITY AND FITNESS
+FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL FERMILAB,
+OR THE URA, OR THE U.S. DEPARTMENT of ENERGY, OR CONTRIBUTORS BE LIABLE
+FOR  ANY  DIRECT, INDIRECT,  INCIDENTAL, SPECIAL, EXEMPLARY, OR
+CONSEQUENTIAL DAMAGES  (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+OF SUBSTITUTE  GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY  OF
+LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT  OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE  POSSIBILITY OF SUCH DAMAGE.
+
+Liabilities of the Government:
+
+This software is provided by URA, independent from its Prime Contract
+with the U.S. Department of Energy. URA is acting independently from
+the Government and in its own private capacity and is not acting on
+behalf of the U.S. Government, nor as its contractor nor its agent.
+Correspondingly, it is understood and agreed that the U.S. Government
+has no connection to this software and in no manner whatsoever shall
+be liable for nor assume any responsibility or obligation for any claim,
+cost, or damages arising out of or resulting from the use of the software
+available from this server.
+
+Export Control:
+
+All documents and software available from this server are subject to U.S.
+export control laws.  Anyone downloading information from this server is
+obligated to secure any necessary Government licenses before exporting
+documents or software obtained from this server.
+ */
+package org.dcache.qos;
+
+import java.util.ArrayList;
+import java.util.List;
+import org.json.JSONArray;
+import org.json.JSONObject;
+
+/**
+ *  Uses the default specification objects to populate the policy from its JSON representation.
+ */
+public class DefaultQoSPolicyJsonDeserializer {
+
+    private static final String NAME = "name";
+    private static final String STATES = "states";
+    private static final String DURATION = "duration";
+    private static final String MEDIA = "media";
+    private static final String STORAGE_ELEMENT = "storageElement";
+    private static final String TYPE = "type";
+    private static final String NUMBER_OF_COPIES = "numberOfCopies";
+    private static final String PARTITION_KEYS = "partitionKeys";
+    private static final String INSTANCE = "instance";
+
+    public static QoSPolicy fromJsonString(String json) {
+        return deserializePolicy(new JSONObject(json));
+    }
+
+    private static QoSPolicy deserializePolicy(JSONObject object) {
+        QoSPolicy policy = new QoSPolicy();
+        policy.setName(object.getString(NAME));
+        JSONArray stateArray = object.getJSONArray(STATES);
+        int len = stateArray.length();
+        List<QoSState> states = new ArrayList<>();
+        for (int i = 0; i < len; ++i) {
+            states.add(deserializeState(stateArray.getJSONObject(i)));
+        }
+        policy.setStates(states);
+        return policy;
+    }
+
+    private static QoSState deserializeState(JSONObject jsonState) {
+        QoSState state = new QoSState();
+        if (jsonState.has(DURATION)) {
+            state.setDuration(jsonState.getString(DURATION));
+        }
+        List<QoSStorageMediumSpecification> media = new ArrayList<>();
+        JSONArray mediaArray = jsonState.getJSONArray(MEDIA);
+        int len = mediaArray.length();
+        for (int i = 0; i < len; ++i) {
+            media.add(deserializeStorageElement(mediaArray.getJSONObject(i)));
+        }
+        state.setMedia(media);
+        return state;
+    }
+
+    private static QoSStorageMediumSpecification deserializeStorageElement(JSONObject jsonMedia) {
+        switch(jsonMedia.getEnum(QoSStorageMedium.class, STORAGE_ELEMENT)) {
+            case DISK:
+                DefaultQoSDiskSpecification diskSpec = new DefaultQoSDiskSpecification();
+                if (jsonMedia.has(TYPE)) {
+                    diskSpec.setType(jsonMedia.getString(TYPE));
+                }
+                diskSpec.setNumberOfCopies(jsonMedia.getInt(NUMBER_OF_COPIES));
+                if (jsonMedia.has(PARTITION_KEYS)) {
+                    List<String> partitionKeys = new ArrayList<>();
+                    JSONArray keyArray = jsonMedia.getJSONArray(PARTITION_KEYS);
+                    int len = keyArray.length();
+                    for (int i = 0; i < len; ++i) {
+                        partitionKeys.add(keyArray.getString(i));
+                    }
+                    diskSpec.setPartitionKeys(partitionKeys);
+                }
+                return diskSpec;
+            case HSM:
+            default:
+                DefaultQoSTapeSpecification tapeSpec = new DefaultQoSTapeSpecification();
+                if (jsonMedia.has(TYPE)) {
+                    tapeSpec.setType(jsonMedia.getString(TYPE));
+                }
+                if (jsonMedia.has(INSTANCE)) {
+                    tapeSpec.setInstance(jsonMedia.getString(INSTANCE));
+                }
+                return tapeSpec;
+        }
+    }
+
+    private DefaultQoSPolicyJsonDeserializer() {
+        // static singleton
+    }
+}