implemented Machines interface

FabAccessAPI/Machines.cs

@@ -0,0 +1,176 @@
+using FabAccessAPI.Schema;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+
+namespace FabAccessAPI {
+    /// <summary>
+    /// Wraps a capability for accessing the Machines subsystem of BFFH
+    /// </summary>
+    class Machines {
+        private IMachines _machinesCap;
+
+        /// <summary>
+        /// Constructs the Wrapper Class from a given capability.
+        /// </summary>
+        /// <param name="machinesCap">The capability that should be wrapped.</param>
+        public Machines(IMachines machinesCap) {
+            _machinesCap = machinesCap;
+        }
+
+        /// <summary>
+        /// List of all machines that BFFH knows about the user has been granted at least read access on
+        /// </summary>
+        /// <returns>ReadOnlyList of available Machines</returns>
+        public async Task<IReadOnlyList<Machine>> ListMachines() {
+            return (await _machinesCap.ListMachines().ConfigureAwait(false)).Select(x => new Machine(x)) as IReadOnlyList<Machine>;
+        }
+
+        /// <summary>
+        /// Access a particular machine by known UUID. This may fail for two reasons:
+        /// The user has not been granted access to know the machine exists or the machine does in fact not exist.
+        /// In both cases the `machine` result will be a NULL-pointer
+        /// </summary>
+        /// <param name="uuid">UUID of the Machine</param>
+        /// <returns>The Machine we requested</returns>
+        public async Task<Machine> GetMachine(UUID uuid) {
+            var mach = (await _machinesCap.GetMachine(uuid).ConfigureAwait(false)).Item1;
+            if (mach == null) {
+                //TODO: Throw a more specific exception!
+                throw new Exception();
+            }
+            return new Machine(mach);
+        }
+    }
+
+    /// <summary>
+    /// A machine. This represents a machine as BFFH thinks about it which may mean
+    ///several machines or just part of a machine in the real world.
+    ///By itself this struct is completely useless since it contains only the information
+    ///that the machine exists the user is allowed to know about that fact. For all further
+    ///information the user has to call the contained capabilities which depending on the
+    ///access level may not be set. For example an admin will have every capability here
+    ///set but a simple user may only have `read` and `write` set while some users may not
+    /// even have `read` set and are unable to even see if the machine is currently in use.
+    /// </summary>
+    class Machine {
+        private Schema.Machine _machine;
+
+        /// <summary>
+        /// Constructs the Wrapper Class from a given capability
+        /// </summary>
+        /// <param name="machine">The capability that should be wrapped.</param>
+        public Machine(Schema.Machine machine) {
+            _machine = machine;
+        }
+
+        // read operations
+
+        /// <summary>
+        /// Get the MInfo Struct for the Machine.
+        /// This contains everything BFFH knows about the Machine.
+        /// </summary>
+        /// <exception cref="UnauthorizedException"></exception>
+        /// <returns>The MInfo Struct describing the Machine</returns>
+        public async Task<Schema.Machine.MInfo> GetMInfo() {
+            var readCap = _machine.Read;
+            if (readCap == null) {
+                throw new UnauthorizedException();
+            }
+
+            return (await _machine.Read.Info().ConfigureAwait(false)).Item1;
+        }
+
+        //write operations
+
+        /// <summary>
+        /// Try to use a machine. Throws a UnauthorizedException if the user does not have the required
+        /// permissions to use this machine.
+        ///
+        /// Use the Ret() Method of the returned Object to return the machine
+        /// </summary>
+        /// <exception cref="UnauthorizedException"></exception>
+        /// <returns>Capability to give back the machine</returns>
+        public Task<Schema.Machine.WriteInterface.IGiveBack> Use() {
+            var writeCap = _machine.Write;
+            if (writeCap == null) {
+                throw new UnauthorizedException();
+            }
+
+            return writeCap.Use();
+        }
+
+       
+        // public void GiveBack(Schema.Machine.WriteInterface.IGiveBack cap) {
+        //     cap.Ret();
+        // }
+
+        //manage operations
+
+        /// <summary>
+        /// After a machine has been used by an user with low enough permissions it's
+        /// in the 'toCheck' state.  This call then allows more priviledged users to
+        /// "check" the machine and move it to the `free` state.
+        ///
+        /// Calling this method signifies that the machine was checked and in an acceptable state.
+        ///  </summary>
+        public async void MarkOk() {
+            var manageCap = _machine.Manage;
+            if (manageCap == null) {
+                throw new UnauthorizedException();
+            }
+            // TODO: Do we really want to check this here?
+            if ((await GetMInfo().ConfigureAwait(false)).State == State.toCheck) {
+                await _machine.Manage.Ok().ConfigureAwait(false);
+            }
+        }
+
+        /// <summary>
+        /// After a machine has been used by an user with low enough permissions it's
+        /// in the 'toCheck' state.  This call then allows more priviledged users to
+        /// "check" the machine and move it to the `free` state.
+        ///
+        /// Calling this method signifies that the machine was checked and in an unacceptable state.
+        /// It will most likely be marked as `blocked` and the previous user will somehow  be informed.
+        ///  </summary>
+        public async void MarkNotOk() {
+            var manageCap = _machine.Manage;
+            if (manageCap == null) {
+                throw new UnauthorizedException();
+            }
+            // TODO: Do we really want to check this here?
+            if ((await GetMInfo().ConfigureAwait(false)).State == State.toCheck) {
+                await _machine.Manage.NotOk().ConfigureAwait(false);
+            }
+        }
+
+        //administrative operations
+
+        /// <summary>
+        /// Forcefully set a machine state.
+        /// </summary>
+        /// <param name="state">The desired machine state.</param>
+        public async void ForceSetState(State state) {
+            var adminCap = _machine.Admin;
+            if (adminCap == null) {
+                throw new UnauthorizedException();
+            }
+
+            await adminCap.ForceSetState(state).ConfigureAwait(false);
+        }
+
+        /// <summary>
+        /// Set the given user as current responsible
+        /// </summary>
+        /// <param name="user">The user</param>
+        public async void ForceSetUser(String user) {
+            var adminCap = _machine.Admin;
+            if (adminCap == null) {
+                throw new UnauthorizedException();
+            }
+
+            await adminCap.ForceSetUser(user).ConfigureAwait(false);
+        }
+    }
+}