feat: define an IPFS Peer, 314

src/Peer.cs

@@ -0,0 +1,160 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace Ipfs
+{
+    /// <summary>
+    ///   A node on the IPFS network.
+    /// </summary>
+    public class Peer : IEquatable<Peer>
+    {
+        static MultiAddress[] noAddress = new MultiAddress[0];
+        const string unknown = "unknown/0.0";
+
+        /// <summary>
+        ///   Universally unique identifier.
+        /// </summary>
+        /// <value>
+        ///   This is the <see cref="MultiHash"/> of the peer's <see cref="PublicKey"/>.
+        /// </value>
+        public MultiHash Id { get; set; }
+
+        /// <summary>
+        ///   The public key of the node.
+        /// </summary>
+        /// <value>
+        ///   The base 64 encoding of the node's public key.  The default is <b>null</b>
+        /// </value>
+        public string PublicKey { get; set; }
+
+        /// <summary>
+        ///   The multiple addresses of the node.
+        /// </summary>
+        /// <value>
+        ///   Where the peer can be found.  The default is an empty sequence.
+        /// </value>
+        public IEnumerable<MultiAddress> Addresses { get; set; } = noAddress;
+
+        /// <summary>
+        ///   The name and version of the IPFS software.
+        /// </summary>
+        /// <value>
+        ///   For example "go-ipfs/0.4.17/".
+        /// </value>
+        /// <remarks>
+        ///   There is no specification that describes the agent version string.  The default
+        ///   is "unknown/0.0".
+        /// </remarks>
+        public string AgentVersion { get; set; } = unknown;
+
+        /// <summary>
+        ///  The name and version of the supported IPFS protocol.
+        /// </summary>
+        /// <value>
+        ///   For example "ipfs/0.1.0".
+        /// </value>
+        /// <remarks>
+        ///   There is no specification that describes the protocol version string. The default
+        ///   is "unknown/0.0".
+        /// </remarks>
+        public string ProtocolVersion { get; set; } = unknown;
+
+        /// <summary>
+        ///   Determines if the information on the peer is valid.
+        /// </summary>
+        /// <returns>
+        ///   <b>true</b> if all validation rules pass; otherwise <b>false</b>.
+        /// </returns>
+        /// <remarks>
+        ///    Verifies that
+        ///    <list type="bullet">
+        ///      <item><description>The <see cref="Id"/> is defined</description></item>
+        ///      <item><description>The <see cref="Id"/> is a hash of the <see cref="PublicKey"/></description></item>
+        ///    </list>
+        /// </remarks>
+        public bool IsValid()
+        {
+            if (Id == null)
+                return false;
+            if (PublicKey != null && !Id.Matches(Convert.FromBase64String(PublicKey)))
+                return false;
+
+            return true;
+        }
+
+        /// <inheritdoc />
+        public override int GetHashCode()
+        {
+            return ToString().GetHashCode();
+        }
+
+        /// <inheritdoc />
+        public override bool Equals(object obj)
+        {
+            var that = obj as Peer;
+            return (that == null)
+                ? false
+                : this.ToString() == that.ToString();
+        }
+
+        /// <inheritdoc />
+        public bool Equals(Peer that)
+        {
+            return this.ToString() == that.ToString();
+        }
+
+        /// <summary>
+        ///   Value equality.
+        /// </summary>
+        public static bool operator ==(Peer a, Peer b)
+        {
+            if (object.ReferenceEquals(a, b)) return true;
+            if (object.ReferenceEquals(a, null)) return false;
+            if (object.ReferenceEquals(b, null)) return false;
+
+            return a.Equals(b);
+        }
+
+        /// <summary>
+        ///   Value inequality.
+        /// </summary>
+        public static bool operator !=(Peer a, Peer b)
+        {
+            if (object.ReferenceEquals(a, b)) return false;
+            if (object.ReferenceEquals(a, null)) return true;
+            if (object.ReferenceEquals(b, null)) return true;
+
+            return !a.Equals(b);
+        }
+
+        /// <summary>
+        ///   Returns the <see cref="Base58"/> encoding of the <see cref="Id"/>.
+        /// </summary>
+        /// <returns>
+        ///   A Base58 representaton of the peer.
+        /// </returns>
+        public override string ToString()
+        {
+            return Id == null ? string.Empty : Id.ToBase58();
+        }
+
+        /// <summary>
+        ///   Implicit casting of a <see cref="string"/> to a <see cref="Peer"/>.
+        /// </summary>
+        /// <param name="s">
+        ///   A <see cref="Base58"/> encoded <see cref="Id"/>.
+        /// </param>
+        /// <returns>
+        ///   A new <see cref="Peer"/>.
+        /// </returns>
+        /// <remarks>
+        ///    Equivalent to <code>new Peer { Id = s }</code>
+        /// </remarks>
+        static public implicit operator Peer(string s)
+        {
+            return new Peer { Id = s };
+        }
+    }
+}

test/PeerTest.cs

@@ -0,0 +1,127 @@
+using System;
+using System.Text;
+using System.Collections.Generic;
+using System.Linq;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using System.IO;
+
+namespace Ipfs
+{
+
+    [TestClass]
+    public class PeerTest
+    {
+        const string marsId = "QmSoLMeWqB7YGVLJN3pNLQpmmEk35v6wYtsMGLzSr5QBU3";
+        const string plutoId = "QmSoLPppuBtQSGwKDZT2M73ULpjvfd3aZ6ha4oFGL1KrGM";
+        const string marsPublicKey = "CAASogEwgZ8wDQYJKoZIhvcNAQEBBQADgY0AMIGJAoGBAKGUtbRQf+a9SBHFEruNAUatS/tsGUnHuCtifGrlbYPELD3UyyhWf/FYczBCavx3i8hIPEW2jQv4ehxQxi/cg9SHswZCQblSi0ucwTBFr8d40JEiyB9CcapiMdFQxdMgGvXEOQdLz1pz+UPUDojkdKZq8qkkeiBn7KlAoGEocnmpAgMBAAE=";
+
+        [TestMethod]
+        public new void ToString()
+        {
+            Assert.AreEqual("", new Peer().ToString());
+            Assert.AreEqual(marsId, new Peer { Id = marsId }.ToString());
+        }
+
+        [TestMethod]
+        public void DefaultValues()
+        {
+            var peer = new Peer();
+            Assert.AreEqual(null, peer.Id);
+            Assert.AreEqual(0, peer.Addresses.Count());
+            Assert.AreEqual("unknown/0.0", peer.ProtocolVersion);
+            Assert.AreEqual("unknown/0.0", peer.AgentVersion);
+            Assert.AreEqual(null, peer.PublicKey);
+            Assert.AreEqual(false, peer.IsValid()); // missing peer ID
+        }
+
+        [TestMethod]
+        public void Validation_No_Id()
+        {
+            var peer = new Peer();
+            Assert.AreEqual(false, peer.IsValid());
+        }
+
+        [TestMethod]
+        public void Validation_With_Id()
+        {
+            Peer peer = marsId;
+            Assert.AreEqual(true, peer.IsValid());
+        }
+
+        [TestMethod]
+        public void Validation_With_Id_Pubkey()
+        {
+            var peer = new Peer
+            {
+                Id = marsId,
+                PublicKey = marsPublicKey
+            };
+            Assert.AreEqual(true, peer.IsValid());
+        }
+
+        [TestMethod]
+        public void Validation_With_Id_Invalid_Pubkey()
+        {
+            var peer = new Peer
+            {
+                Id = plutoId,
+                PublicKey = marsPublicKey
+            };
+            Assert.AreEqual(false, peer.IsValid());
+        }
+
+        [TestMethod]
+        public void Value_Equality()
+        {
+            var a0 = new Peer { Id = marsId };
+            var a1 = new Peer { Id = marsId };
+            var b = new Peer { Id = plutoId };
+            Peer c = null;
+            Peer d = null;
+
+            Assert.IsTrue(c == d);
+            Assert.IsFalse(c == b);
+            Assert.IsFalse(b == c);
+
+            Assert.IsFalse(c != d);
+            Assert.IsTrue(c != b);
+            Assert.IsTrue(b != c);
+
+#pragma warning disable 1718
+            Assert.IsTrue(a0 == a0);
+            Assert.IsTrue(a0 == a1);
+            Assert.IsFalse(a0 == b);
+
+#pragma warning disable 1718
+            Assert.IsFalse(a0 != a0);
+            Assert.IsFalse(a0 != a1);
+            Assert.IsTrue(a0 != b);
+
+            Assert.IsTrue(a0.Equals(a0));
+            Assert.IsTrue(a0.Equals(a1));
+            Assert.IsFalse(a0.Equals(b));
+
+            Assert.AreEqual(a0, a0);
+            Assert.AreEqual(a0, a1);
+            Assert.AreNotEqual(a0, b);
+
+            Assert.AreEqual<Peer>(a0, a0);
+            Assert.AreEqual<Peer>(a0, a1);
+            Assert.AreNotEqual<Peer>(a0, b);
+
+            Assert.AreEqual(a0.GetHashCode(), a0.GetHashCode());
+            Assert.AreEqual(a0.GetHashCode(), a1.GetHashCode());
+            Assert.AreNotEqual(a0.GetHashCode(), b.GetHashCode());
+        }
+
+
+        [TestMethod]
+        public void Implicit_Conversion_From_String()
+        {
+            Peer a = marsId;
+            Assert.IsInstanceOfType(a, typeof(Peer));
+        }
+
+    }
+}
+