feat: Add support for resource tagging

4 files changed, 180 insertions, 0 deletions

diff --git a/opendc/opendc-core/src/main/kotlin/com/atlarge/opendc/core/resource/Resource.kt b/opendc/opendc-core/src/main/kotlin/com/atlarge/opendc/core/resource/Resource.kt
new file mode 100644
index 00000000..25a494bc
--- /dev/null
+++ b/opendc/opendc-core/src/main/kotlin/com/atlarge/opendc/core/resource/Resource.kt
@@ -0,0 +1,37 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2020 atlarge-research
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.atlarge.opendc.core.resource
+
+import com.atlarge.opendc.core.Identity
+
+/**
+ * Represents a generic cloud resource.
+ */
+public interface Resource : Identity {
+    /**
+     * The tags of this cloud resource.
+     */
+    public val tags: TagContainer
+}
diff --git a/opendc/opendc-core/src/main/kotlin/com/atlarge/opendc/core/resource/TagContainer.kt b/opendc/opendc-core/src/main/kotlin/com/atlarge/opendc/core/resource/TagContainer.kt
new file mode 100644
index 00000000..4167cd20
--- /dev/null
+++ b/opendc/opendc-core/src/main/kotlin/com/atlarge/opendc/core/resource/TagContainer.kt
@@ -0,0 +1,62 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2020 atlarge-research
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.atlarge.opendc.core.resource
+
+/**
+ * An immutable map containing the tags of some resource.
+ */
+public interface TagContainer {
+    /**
+     * The keys in this container.
+     */
+    public val keys: Collection<TagKey<*>>
+
+    /**
+     * Determine if this container contains a tag with the specified [TagKey].
+     *
+     * @param key The key of the tag to check for.
+     * @return `true` if the tag is in the container, `false` otherwise.
+     */
+    public operator fun contains(key: TagKey<*>): Boolean
+
+    /**
+     * Obtain the tag with the specified [TagKey].
+     *
+     * @param key The key of the tag to obtain.
+     * @return The value of the tag.
+     * @throws IllegalArgumentException if the tag does not exists in the container.
+     */
+    public operator fun <T : Any> get(key: TagKey<T>): T
+
+    /**
+     * Return the result of associating the specified [value] with the specified [key] in this container.
+     */
+    public fun <T : Any> put(key: TagKey<T>, value: T): TagContainer
+
+    /**
+     * Return the result of removing the specified [key] and its corresponding value from this container.
+     */
+    public fun remove(key: TagKey<*>): TagContainer
+}
diff --git a/opendc/opendc-core/src/main/kotlin/com/atlarge/opendc/core/resource/TagContainerImpl.kt b/opendc/opendc-core/src/main/kotlin/com/atlarge/opendc/core/resource/TagContainerImpl.kt
new file mode 100644
index 00000000..1acc7de4
--- /dev/null
+++ b/opendc/opendc-core/src/main/kotlin/com/atlarge/opendc/core/resource/TagContainerImpl.kt
@@ -0,0 +1,51 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2020 atlarge-research
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.atlarge.opendc.core.resource
+
+/**
+ * Default implementation of [TagContainer] interface.
+ *
+ * @property map The internal map object to hold the tags.
+ */
+public class TagContainerImpl private constructor(private val map: Map<TagKey<*>, Any>) : TagContainer {
+    /**
+     * Construct an empty [TagContainerImpl].
+     */
+    public constructor() : this(emptyMap())
+
+    override val keys: Collection<TagKey<*>>
+        get() = map.keys
+
+    override fun contains(key: TagKey<*>): Boolean = map.contains(key)
+
+    override fun <T : Any> get(key: TagKey<T>): T {
+        @Suppress("UNCHECKED_CAST")
+        return map.getValue(key) as T
+    }
+
+    override fun <T : Any> put(key: TagKey<T>, value: T): TagContainer = TagContainerImpl(map.plus(key to value))
+
+    override fun remove(key: TagKey<*>): TagContainer = TagContainerImpl(map.minus(key))
+}
diff --git a/opendc/opendc-core/src/main/kotlin/com/atlarge/opendc/core/resource/TagKey.kt b/opendc/opendc-core/src/main/kotlin/com/atlarge/opendc/core/resource/TagKey.kt
new file mode 100644
index 00000000..759f4461
--- /dev/null
+++ b/opendc/opendc-core/src/main/kotlin/com/atlarge/opendc/core/resource/TagKey.kt
@@ -0,0 +1,30 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2020 atlarge-research
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.atlarge.opendc.core.resource
+
+/**
+ * Represents a typed key for a resource tag with a unique name.
+ */
+public data class TagKey<T : Any>(val name: String)