Initial implementation

Sources/MCP/Server/Resources.swift

@@ -0,0 +1,195 @@
+import Foundation
+
+/// The Model Context Protocol (MCP) provides a standardized way
+/// for servers to expose resources to clients.
+/// Resources allow servers to share data that provides context to language models,
+/// such as files, database schemas, or application-specific information.
+/// Each resource is uniquely identified by a URI.
+///
+/// - SeeAlso: https://spec.modelcontextprotocol.io/specification/2024-11-05/server/resources/
+public struct Resource: Hashable, Codable, Sendable {
+    /// The resource name
+    public var name: String
+    /// The resource URI
+    public var uri: String
+    /// The resource description
+    public var description: String?
+    /// The resource MIME type
+    public var mimeType: String?
+    /// The resource metadata
+    public var metadata: [String: String]?
+
+    public init(
+        name: String,
+        uri: String,
+        description: String? = nil,
+        mimeType: String? = nil,
+        metadata: [String: String]? = nil
+    ) {
+        self.name = name
+        self.uri = uri
+        self.description = description
+        self.mimeType = mimeType
+        self.metadata = metadata
+    }
+
+    /// Content of a resource.
+    public struct Content: Hashable, Codable, Sendable {
+        /// The resource URI
+        public let uri: String
+        /// The resource MIME type
+        public let mimeType: String?
+        /// The resource text content
+        public let text: String?
+        /// The resource binary content
+        public let blob: String?
+
+        public static func text(_ content: String, uri: String, mimeType: String? = nil) -> Self {
+            .init(uri: uri, mimeType: mimeType, text: content)
+        }
+
+        public static func binary(_ data: Data, uri: String, mimeType: String? = nil) -> Self {
+            .init(uri: uri, mimeType: mimeType, blob: data.base64EncodedString())
+        }
+
+        private init(uri: String, mimeType: String? = nil, text: String? = nil) {
+            self.uri = uri
+            self.mimeType = mimeType
+            self.text = text
+            self.blob = nil
+        }
+
+        private init(uri: String, mimeType: String? = nil, blob: String) {
+            self.uri = uri
+            self.mimeType = mimeType
+            self.text = nil
+            self.blob = blob
+        }
+    }
+
+    /// A resource template.
+    public struct Template: Hashable, Codable, Sendable {
+        /// The URI template pattern
+        public var uriTemplate: String
+        /// The template name
+        public var name: String
+        /// The template description
+        public var description: String?
+        /// The resource MIME type
+        public var mimeType: String?
+
+        public init(
+            uriTemplate: String,
+            name: String,
+            description: String? = nil,
+            mimeType: String? = nil
+        ) {
+            self.uriTemplate = uriTemplate
+            self.name = name
+            self.description = description
+            self.mimeType = mimeType
+        }
+    }
+}
+
+// MARK: -
+
+/// To discover available resources, clients send a `resources/list` request.
+/// - SeeAlso: https://spec.modelcontextprotocol.io/specification/2024-11-05/server/resources/#listing-resources
+public enum ListResources: Method {
+    public static let name: String = "resources/list"
+
+    public struct Parameters: Hashable, Codable, Sendable {
+        public let cursor: String?
+
+        public init(cursor: String? = nil) {
+            self.cursor = cursor
+        }
+    }
+
+    public struct Result: Hashable, Codable, Sendable {
+        public let resources: [Resource]
+        public let nextCursor: String?
+
+        public init(resources: [Resource], nextCursor: String? = nil) {
+            self.resources = resources
+            self.nextCursor = nextCursor
+        }
+    }
+}
+
+/// To retrieve resource contents, clients send a `resources/read` request:
+/// - SeeAlso: https://spec.modelcontextprotocol.io/specification/2024-11-05/server/resources/#reading-resources
+public enum ReadResource: Method {
+    public static let name: String = "resources/read"
+
+    public struct Parameters: Hashable, Codable, Sendable {
+        public let uri: String
+
+        public init(uri: String) {
+            self.uri = uri
+        }
+    }
+
+    public struct Result: Hashable, Codable, Sendable {
+        public let contents: [Resource.Content]
+
+        public init(contents: [Resource.Content]) {
+            self.contents = contents
+        }
+    }
+}
+
+/// To discover available resource templates, clients send a `resources/templates/list` request.
+/// - SeeAlso: https://spec.modelcontextprotocol.io/specification/2024-11-05/server/resources/#resource-templates
+public enum ListResourceTemplates: Method {
+    public static let name: String = "resources/templates/list"
+
+    public typealias Parameters = Empty
+
+    public struct Result: Hashable, Codable, Sendable {
+        public let templates: [Resource.Template]
+
+        public init(templates: [Resource.Template]) {
+            self.templates = templates
+        }
+
+        private enum CodingKeys: String, CodingKey {
+            case templates = "resourceTemplates"
+        }
+    }
+}
+
+/// When the list of available resources changes, servers that declared the listChanged capability SHOULD send a notification.
+/// - SeeAlso: https://spec.modelcontextprotocol.io/specification/2024-11-05/server/resources/#list-changed-notification
+public struct ResourceListChangedNotification: Notification {
+    public static let name: String = "notifications/resources/list_changed"
+
+    public typealias Parameters = Empty
+}
+
+/// Clients can subscribe to specific resources and receive notifications when they change.
+/// - SeeAlso: https://spec.modelcontextprotocol.io/specification/2024-11-05/server/resources/#subscriptions
+public enum ResourceSubscribe: Method {
+    public static let name: String = "resources/subscribe"
+
+    public struct Parameters: Hashable, Codable, Sendable {
+        public let uri: String
+    }
+
+    public typealias Result = Empty
+}
+
+/// When a resource changes, servers that declared the updated capability SHOULD send a notification to subscribed clients.
+/// - SeeAlso: https://spec.modelcontextprotocol.io/specification/2024-11-05/server/resources/#subscriptions
+public struct ResourceUpdatedNotification: Notification {
+    public static let name: String = "notifications/resources/updated"
+
+    public struct Parameters: Hashable, Codable, Sendable {
+        public let uri: String
+
+        public init(uri: String) {
+            self.uri = uri
+        }
+    }
+}