Add 'direct' keyword to descendants option to query direct children (ep1)

[cps.git] / cps-service / src / main / java / org / onap / cps / spi / FetchDescendantsOption.java

diff --git a/cps-service/src/main/java/org/onap/cps/spi/FetchDescendantsOption.java b/cps-service/src/main/java/org/onap/cps/spi/FetchDescendantsOption.java
index 0c994d8..3b90b06 100644 (file)
--- a/cps-service/src/main/java/org/onap/cps/spi/FetchDescendantsOption.java
+++ b/cps-service/src/main/java/org/onap/cps/spi/FetchDescendantsOption.java
@@ -1,6 +1,8 @@
 /*
  *  ============LICENSE_START=======================================================
  *  Copyright (C) 2021 Pantheon.tech
+ *  Copyright (C) 2022-2023 Nordix Foundation
+ *  Modifications Copyright (C) 2023 TechMahindra Ltd.
  *  ================================================================================
  *  Licensed under the Apache License, Version 2.0 (the "License");
  *  you may not use this file except in compliance with the License.
@@ -19,7 +21,109 @@
 
 package org.onap.cps.spi;
 
-public enum FetchDescendantsOption {
-    OMIT_DESCENDANTS,
-    INCLUDE_ALL_DESCENDANTS
+import com.google.common.base.Strings;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+import lombok.RequiredArgsConstructor;
+import org.onap.cps.spi.exceptions.DataValidationException;
+
+@RequiredArgsConstructor
+public class FetchDescendantsOption {
+
+    public static final FetchDescendantsOption DIRECT_CHILDREN_ONLY
+        = new FetchDescendantsOption(1, "DirectChildrenOnly");
+    public static final FetchDescendantsOption OMIT_DESCENDANTS
+        = new FetchDescendantsOption(0, "OmitDescendants");
+    public static final FetchDescendantsOption INCLUDE_ALL_DESCENDANTS
+        = new FetchDescendantsOption(-1, "IncludeAllDescendants");
+
+    FetchDescendantsOption(final int depth) {
+        this(depth, "Depth=" + depth);
+    }
+
+    private static final Pattern FETCH_DESCENDANTS_OPTION_PATTERN =
+        Pattern.compile("^$|^all$|^none$|^direct$|^[0-9]+$|^-1$|^1$");
+
+    private final int depth;
+
+    private final String optionName;
+
+    /**
+     * Has next depth.
+     *
+     * @return true if next level of depth is available
+     * @throws IllegalArgumentException when depth less than -1
+     */
+    public boolean hasNext() {
+        validateDepth(depth);
+        return depth > 0 || this.depth == INCLUDE_ALL_DESCENDANTS.depth;
+    }
+
+    /**
+     * Next fetch descendants option.
+     *
+     * @return the next fetch descendants option
+     * @throws IllegalArgumentException when depth less than -1 or 0
+     */
+    public FetchDescendantsOption next() {
+        if (depth == 0) {
+            throw new IllegalArgumentException("Do not use next() method with zero depth");
+        }
+        final FetchDescendantsOption nextDescendantsOption = this.depth == INCLUDE_ALL_DESCENDANTS.depth
+                ? INCLUDE_ALL_DESCENDANTS : new FetchDescendantsOption(depth - 1);
+        validateDepth(nextDescendantsOption.depth);
+        return nextDescendantsOption;
+    }
+
+    /**
+     * Get depth.
+     * @return depth: -1 for all descendants, 0 for no descendants, or positive value for fixed level of descendants
+     */
+    public int getDepth() {
+        return depth;
+    }
+
+    /**
+     * get fetch descendants option for given descendant.
+     *
+     * @param fetchDescendantsOptionAsString fetch descendants option string
+     * @return fetch descendants option for given descendant
+     */
+    public static FetchDescendantsOption getFetchDescendantsOption(final String fetchDescendantsOptionAsString) {
+        validateFetchDescendantsOption(fetchDescendantsOptionAsString);
+        if (Strings.isNullOrEmpty(fetchDescendantsOptionAsString)
+                || "0".equals(fetchDescendantsOptionAsString) || "none".equals(fetchDescendantsOptionAsString)) {
+            return FetchDescendantsOption.OMIT_DESCENDANTS;
+        } else if ("-1".equals(fetchDescendantsOptionAsString) || "all".equals(fetchDescendantsOptionAsString)) {
+            return FetchDescendantsOption.INCLUDE_ALL_DESCENDANTS;
+        } else if ("1".equals(fetchDescendantsOptionAsString) || "direct".equals(fetchDescendantsOptionAsString)) {
+            return FetchDescendantsOption.DIRECT_CHILDREN_ONLY;
+        } else {
+            final Integer depth = Integer.valueOf(fetchDescendantsOptionAsString);
+            return new FetchDescendantsOption(depth);
+        }
+    }
+
+    @Override
+    public String toString() {
+        return optionName;
+    }
+
+    private static void validateFetchDescendantsOption(final String fetchDescendantsOptionAsString) {
+        if (Strings.isNullOrEmpty(fetchDescendantsOptionAsString)) {
+            return;
+        }
+        final Matcher matcher = FETCH_DESCENDANTS_OPTION_PATTERN.matcher(fetchDescendantsOptionAsString);
+        if (!matcher.matches()) {
+            throw new DataValidationException("FetchDescendantsOption validation error.",
+                    fetchDescendantsOptionAsString + " is not valid fetch descendants option");
+        }
+    }
+
+    private static void validateDepth(final int depth) {
+        if (depth < -1) {
+            throw new IllegalArgumentException("A depth of less than minus one is not allowed");
+        }
+    }
+
 }