5fb501ad312ffe88b0644bd5bf4fecb3327a05e4-PR-1445

Build # 5fb501ad312ffe88b0644bd5bf4fecb3327a05e4-PR-1445

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Pull Request Pull Request #1445: Oracle policy contract

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98.48

/src/neo/SmartContract/Native/Oracle/OracleContract.cs

using Neo.Cryptography.ECC;
using Neo.IO;
using Neo.Ledger;
using Neo.Persistence;
using Neo.SmartContract.Manifest;
using Neo.VM;
using Neo.VM.Types;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Numerics;
using System.Text;
using Array = Neo.VM.Types.Array;

namespace Neo.SmartContract.Native.Oracle
{
    public sealed class OracleContract : NativeContract
    {
        public override string ServiceName => "Neo.Native.Oracle";

        public override int Id => -4;

        private const byte Prefix_Validator = 24;
        private const byte Prefix_HttpConfig = 25;
        private const byte Prefix_PerRequestFee = 26;

        public OracleContract()
        {
            Manifest.Features = ContractFeatures.HasStorage;
        }

        internal override bool Initialize(ApplicationEngine engine)
        {
            if (!base.Initialize(engine)) return false;
            engine.Snapshot.Storages.Add(CreateStorageKey(Prefix_HttpConfig, Encoding.UTF8.GetBytes("HttpTimeout")), new StorageItem
            {
                Value = new ByteArray(BitConverter.GetBytes(5000)).GetSpan().ToArray()
            });
            engine.Snapshot.Storages.Add(CreateStorageKey(Prefix_PerRequestFee), new StorageItem
            {
                Value = BitConverter.GetBytes(1000)
            });
            return true;
        }

        /// <summary>
        /// Consensus node can delegate third party to operate Oracle nodes
        /// </summary>
        /// <param name="engine">VM</param>
        /// <param name="args">Parameter Array</param>
        /// <returns>Returns true if the execution is successful, otherwise returns false</returns>
        [ContractMethod(0_03000000, ContractParameterType.Boolean, ParameterTypes = new[] { ContractParameterType.ByteArray, ContractParameterType.ByteArray }, ParameterNames = new[] { "consignorPubKey", "consigneePubKey" })]
        private StackItem DelegateOracleValidator(ApplicationEngine engine, Array args)
        {
            StoreView snapshot = engine.Snapshot;
            ECPoint consignorPubKey = args[0].GetSpan().AsSerializable<ECPoint>();
            ECPoint consigneePubKey = args[1].GetSpan().AsSerializable<ECPoint>();
            ECPoint[] cnPubKeys = NativeContract.NEO.GetValidators(snapshot);
            if (!cnPubKeys.Contains(consignorPubKey)) return false;
            UInt160 account = Contract.CreateSignatureRedeemScript(consignorPubKey).ToScriptHash();
            if (!InteropService.Runtime.CheckWitnessInternal(engine, account)) return false;
            StorageKey key = CreateStorageKey(Prefix_Validator, consignorPubKey);
            StorageItem item = snapshot.Storages.GetAndChange(key, () => new StorageItem());
            item.Value = consigneePubKey.ToArray();

            byte[] prefixKey = StorageKey.CreateSearchPrefix(Id, new[] { Prefix_Validator });
            List<ECPoint> delegatedOracleValidators = snapshot.Storages.Find(prefixKey).Select(p =>
              (
                  p.Key.Key.AsSerializable<ECPoint>(1)
              )).ToList();
            foreach (var validator in delegatedOracleValidators)
            {
                if (!cnPubKeys.Contains(validator))
                {
                    snapshot.Storages.Delete(CreateStorageKey(Prefix_Validator, validator));
                }
            }
            return true;
        }

        /// <summary>
        /// Get current authorized Oracle validator.
        /// </summary>
        /// <param name="engine">VM</param>
        /// <param name="args">Parameter Array</param>
        /// <returns>Authorized Oracle validator</returns>
        [ContractMethod(0_01000000, ContractParameterType.Array)]
        private StackItem GetOracleValidators(ApplicationEngine engine, Array args)
        {
            return new Array(engine.ReferenceCounter, GetOracleValidators(engine.Snapshot).Select(p => (StackItem)p.ToArray()));
        }

        /// <summary>
        /// Get current authorized Oracle validator
        /// </summary>
        /// <param name="snapshot">snapshot</param>
        /// <returns>Authorized Oracle validator</returns>
        public ECPoint[] GetOracleValidators(StoreView snapshot)
        {
            ECPoint[] cnPubKeys = NativeContract.NEO.GetValidators(snapshot);
            ECPoint[] oraclePubKeys = new ECPoint[cnPubKeys.Length];
            System.Array.Copy(cnPubKeys, oraclePubKeys, cnPubKeys.Length);
            for (int index = 0; index < oraclePubKeys.Length; index++)
            {
                var oraclePubKey = oraclePubKeys[index];
                StorageKey key = CreateStorageKey(Prefix_Validator, oraclePubKey);
                ECPoint delegatePubKey = snapshot.Storages.TryGet(key)?.Value.AsSerializable<ECPoint>();
                if (delegatePubKey != null) { oraclePubKeys[index] = delegatePubKey; }
            }
            return oraclePubKeys;
        }

        /// <summary>
        /// Get number of current authorized Oracle validator
        /// </summary>
        /// <param name="engine">VM</param>
        /// <param name="args">Parameter Array</param>
        /// <returns>The number of authorized Oracle validator</returns>
        [ContractMethod(0_01000000, ContractParameterType.Integer)]
        private StackItem GetOracleValidatorsCount(ApplicationEngine engine, Array args)
        {
            return GetOracleValidatorsCount(engine.Snapshot);
        }

        /// <summary>
        /// Get number of current authorized Oracle validator
        /// </summary>
        /// <param name="snapshot">snapshot</param>
        /// <returns>The number of authorized Oracle validator</returns>
        public BigInteger GetOracleValidatorsCount(StoreView snapshot)
        {
            return GetOracleValidators(snapshot).Length;
        }

        /// <summary>
        /// Create a Oracle multisignature address
        /// </summary>
        /// <param name="snapshot">snapshot</param>
        /// <returns>Oracle multisignature address</returns>
        public UInt160 GetOracleMultiSigAddress(StoreView snapshot)
        {
            ECPoint[] cnPubKeys = NativeContract.NEO.GetValidators(snapshot);
            return Contract.CreateMultiSigRedeemScript(cnPubKeys.Length - (cnPubKeys.Length - 1) / 3, cnPubKeys).ToScriptHash();
        }

        /// <summary>
        /// Set HttpConfig
        /// </summary>
        /// <param name="engine">VM</param>
        /// <param name="args">Parameter Array</param>
        /// <returns>Returns true if the execution is successful, otherwise returns false</returns>
        [ContractMethod(0_03000000, ContractParameterType.Boolean, ParameterTypes = new[] { ContractParameterType.String, ContractParameterType.ByteArray }, ParameterNames = new[] { "configKey", "configValue" })]
        private StackItem SetConfig(ApplicationEngine engine, Array args)
        {
            StoreView snapshot = engine.Snapshot;
            UInt160 account = GetOracleMultiSigAddress(snapshot);
            if (!InteropService.Runtime.CheckWitnessInternal(engine, account)) return false;
            string key = args[0].GetString();
            ByteArray value = args[1].GetSpan().ToArray();
            StorageItem storage = snapshot.Storages.GetAndChange(CreateStorageKey(Prefix_HttpConfig, Encoding.UTF8.GetBytes(key)));
            storage.Value = value.GetSpan().ToArray();
            return true;
        }

        /// <summary>
        /// Get HttpConfig
        /// </summary>
        /// <param name="engine">VM</param>
        /// <returns>value</returns>
        [ContractMethod(0_01000000, ContractParameterType.Array, ParameterTypes = new[] { ContractParameterType.String }, ParameterNames = new[] { "configKey" })]
        private StackItem GetConfig(ApplicationEngine engine, Array args)
        {
            StoreView snapshot = engine.Snapshot;
            string key = args[0].GetString();
            return GetConfig(snapshot, key);
        }

        /// <summary>
        /// Get HttpConfig
        /// </summary>
        /// <param name="snapshot">snapshot</param>
        /// <param name="key">key</param>
        /// <returns>value</returns>
        public ByteArray GetConfig(StoreView snapshot, string key)
        {
            StorageItem storage = snapshot.Storages.GetAndChange(CreateStorageKey(Prefix_HttpConfig, Encoding.UTF8.GetBytes(key)));
            return storage.Value;
        }

        /// <summary>
        /// Set PerRequestFee
        /// </summary>
        /// <param name="engine">VM</param>
        /// <param name="args">Parameter Array</param>
        /// <returns>Returns true if the execution is successful, otherwise returns false</returns>
        [ContractMethod(0_03000000, ContractParameterType.Boolean, ParameterTypes = new[] { ContractParameterType.Integer }, ParameterNames = new[] { "fee" })]
        private StackItem SetPerRequestFee(ApplicationEngine engine, Array args)
        {
            StoreView snapshot = engine.Snapshot;
            UInt160 account = GetOracleMultiSigAddress(snapshot);
            if (!InteropService.Runtime.CheckWitnessInternal(engine, account)) return false;
            int perRequestFee = (int)args[0].GetBigInteger();
            if (perRequestFee <= 0) return false;
            StorageItem storage = snapshot.Storages.GetAndChange(CreateStorageKey(Prefix_PerRequestFee));
            storage.Value = BitConverter.GetBytes(perRequestFee);
            return true;
        }

        /// <summary>
        /// Get PerRequestFee
        /// </summary>
        /// <param name="engine">VM</param>
        /// <param name="args">Parameter Array</param>
        /// <returns>Value</returns>
        [ContractMethod(0_01000000, ContractParameterType.Integer, SafeMethod = true)]
        private StackItem GetPerRequestFee(ApplicationEngine engine, Array args)
        {
            return new Integer(GetPerRequestFee(engine.Snapshot));
        }

        /// <summary>
        /// Get PerRequestFee
        /// </summary>
        /// <param name="snapshot">snapshot</param>
        /// <returns>Value</returns>
        public int GetPerRequestFee(StoreView snapshot)
        {
            return BitConverter.ToInt32(snapshot.Storages[CreateStorageKey(Prefix_PerRequestFee)].Value, 0);
        }
    }
}

1	using Neo.Cryptography.ECC;
2	using Neo.IO;
3	using Neo.Ledger;
4	using Neo.Persistence;
5	using Neo.SmartContract.Manifest;
6	using Neo.VM;
7	using Neo.VM.Types;
8	using System;
9	using System.Collections.Generic;
10	using System.Linq;
11	using System.Numerics;
12	using System.Text;
13	using Array = Neo.VM.Types.Array;
14
15	namespace Neo.SmartContract.Native.Oracle
16	{
17	public sealed class OracleContract : NativeContract
18	{
19	public override string ServiceName => "Neo.Native.Oracle";	2✔
20
21	public override int Id => -4;	369✔
22
23	private const byte Prefix_Validator = 24;
24	private const byte Prefix_HttpConfig = 25;
25	private const byte Prefix_PerRequestFee = 26;
26
27	public OracleContract()	1✔
28	{	1✔
29	Manifest.Features = ContractFeatures.HasStorage;	1✔
30	}	1✔
31
32	internal override bool Initialize(ApplicationEngine engine)
33	{	19✔
34	if (!base.Initialize(engine)) return false;	×
35	engine.Snapshot.Storages.Add(CreateStorageKey(Prefix_HttpConfig, Encoding.UTF8.GetBytes("HttpTimeout")), new StorageItem	19✔
36	{	19✔
37	Value = new ByteArray(BitConverter.GetBytes(5000)).GetSpan().ToArray()	19✔
38	});	19✔
39	engine.Snapshot.Storages.Add(CreateStorageKey(Prefix_PerRequestFee), new StorageItem	19✔
40	{	19✔
41	Value = BitConverter.GetBytes(1000)	19✔
42	});	19✔
43	return true;	19✔
44	}	19✔
45
46	/// <summary>
47	/// Consensus node can delegate third party to operate Oracle nodes
48	/// </summary>
49	/// <param name="engine">VM</param>
50	/// <param name="args">Parameter Array</param>
51	/// <returns>Returns true if the execution is successful, otherwise returns false</returns>
52	[ContractMethod(0_03000000, ContractParameterType.Boolean, ParameterTypes = new[] { ContractParameterType.ByteArray, ContractParameterType.ByteArray }, ParameterNames = new[] { "consignorPubKey", "consigneePubKey" })]
53	private StackItem DelegateOracleValidator(ApplicationEngine engine, Array args)
54	{	24✔
55	StoreView snapshot = engine.Snapshot;	24✔
56	ECPoint consignorPubKey = args[0].GetSpan().AsSerializable<ECPoint>();	24✔
57	ECPoint consigneePubKey = args[1].GetSpan().AsSerializable<ECPoint>();	24✔
58	ECPoint[] cnPubKeys = NativeContract.NEO.GetValidators(snapshot);	24✔
59	if (!cnPubKeys.Contains(consignorPubKey)) return false;	30✔
60	UInt160 account = Contract.CreateSignatureRedeemScript(consignorPubKey).ToScriptHash();	18✔
61	if (!InteropService.Runtime.CheckWitnessInternal(engine, account)) return false;	30✔
62	StorageKey key = CreateStorageKey(Prefix_Validator, consignorPubKey);	6✔
63	StorageItem item = snapshot.Storages.GetAndChange(key, () => new StorageItem());	12✔
64	item.Value = consigneePubKey.ToArray();	6✔
65
66	byte[] prefixKey = StorageKey.CreateSearchPrefix(Id, new[] { Prefix_Validator });	6✔
67	List<ECPoint> delegatedOracleValidators = snapshot.Storages.Find(prefixKey).Select(p =>	6✔
68	(	18✔
69	p.Key.Key.AsSerializable<ECPoint>(1)	18✔
70	)).ToList();	18✔
71	foreach (var validator in delegatedOracleValidators)	42✔
72	{	12✔
73	if (!cnPubKeys.Contains(validator))	12✔
74	{	6✔
75	snapshot.Storages.Delete(CreateStorageKey(Prefix_Validator, validator));	6✔
76	}	6✔
77	}	12✔
78	return true;	6✔
79	}	24✔
80
81	/// <summary>
82	/// Get current authorized Oracle validator.
83	/// </summary>
84	/// <param name="engine">VM</param>
85	/// <param name="args">Parameter Array</param>
86	/// <returns>Authorized Oracle validator</returns>
87	[ContractMethod(0_01000000, ContractParameterType.Array)]
88	private StackItem GetOracleValidators(ApplicationEngine engine, Array args)
89	{	12✔
90	return new Array(engine.ReferenceCounter, GetOracleValidators(engine.Snapshot).Select(p => (StackItem)p.ToArray()));	96✔
91	}	12✔
92
93	/// <summary>
94	/// Get current authorized Oracle validator
95	/// </summary>
96	/// <param name="snapshot">snapshot</param>
97	/// <returns>Authorized Oracle validator</returns>
98	public ECPoint[] GetOracleValidators(StoreView snapshot)
99	{	36✔
100	ECPoint[] cnPubKeys = NativeContract.NEO.GetValidators(snapshot);	36✔
101	ECPoint[] oraclePubKeys = new ECPoint[cnPubKeys.Length];	36✔
102	System.Array.Copy(cnPubKeys, oraclePubKeys, cnPubKeys.Length);	36✔
103	for (int index = 0; index < oraclePubKeys.Length; index++)	576✔
104	{	252✔
105	var oraclePubKey = oraclePubKeys[index];	252✔
106	StorageKey key = CreateStorageKey(Prefix_Validator, oraclePubKey);	252✔
107	ECPoint delegatePubKey = snapshot.Storages.TryGet(key)?.Value.AsSerializable<ECPoint>();	252✔
108	if (delegatePubKey != null) { oraclePubKeys[index] = delegatePubKey; }	288✔
109	}	252✔
110	return oraclePubKeys;	36✔
111	}	36✔
112
113	/// <summary>
114	/// Get number of current authorized Oracle validator
115	/// </summary>
116	/// <param name="engine">VM</param>
117	/// <param name="args">Parameter Array</param>
118	/// <returns>The number of authorized Oracle validator</returns>
119	[ContractMethod(0_01000000, ContractParameterType.Integer)]
120	private StackItem GetOracleValidatorsCount(ApplicationEngine engine, Array args)
121	{	6✔
122	return GetOracleValidatorsCount(engine.Snapshot);	6✔
123	}	6✔
124
125	/// <summary>
126	/// Get number of current authorized Oracle validator
127	/// </summary>
128	/// <param name="snapshot">snapshot</param>
129	/// <returns>The number of authorized Oracle validator</returns>
130	public BigInteger GetOracleValidatorsCount(StoreView snapshot)
131	{	6✔
132	return GetOracleValidators(snapshot).Length;	6✔
133	}	6✔
134
135	/// <summary>
136	/// Create a Oracle multisignature address
137	/// </summary>
138	/// <param name="snapshot">snapshot</param>
139	/// <returns>Oracle multisignature address</returns>
140	public UInt160 GetOracleMultiSigAddress(StoreView snapshot)
141	{	42✔
142	ECPoint[] cnPubKeys = NativeContract.NEO.GetValidators(snapshot);	42✔
143	return Contract.CreateMultiSigRedeemScript(cnPubKeys.Length - (cnPubKeys.Length - 1) / 3, cnPubKeys).ToScriptHash();	42✔
144	}	42✔
145
146	/// <summary>
147	/// Set HttpConfig
148	/// </summary>
149	/// <param name="engine">VM</param>
150	/// <param name="args">Parameter Array</param>
151	/// <returns>Returns true if the execution is successful, otherwise returns false</returns>
152	[ContractMethod(0_03000000, ContractParameterType.Boolean, ParameterTypes = new[] { ContractParameterType.String, ContractParameterType.ByteArray }, ParameterNames = new[] { "configKey", "configValue" })]
153	private StackItem SetConfig(ApplicationEngine engine, Array args)
154	{	12✔
155	StoreView snapshot = engine.Snapshot;	12✔
156	UInt160 account = GetOracleMultiSigAddress(snapshot);	12✔
157	if (!InteropService.Runtime.CheckWitnessInternal(engine, account)) return false;	18✔
158	string key = args[0].GetString();	6✔
159	ByteArray value = args[1].GetSpan().ToArray();	6✔
160	StorageItem storage = snapshot.Storages.GetAndChange(CreateStorageKey(Prefix_HttpConfig, Encoding.UTF8.GetBytes(key)));	6✔
161	storage.Value = value.GetSpan().ToArray();	6✔
162	return true;	6✔
163	}	12✔
164
165	/// <summary>
166	/// Get HttpConfig
167	/// </summary>
168	/// <param name="engine">VM</param>
169	/// <returns>value</returns>
170	[ContractMethod(0_01000000, ContractParameterType.Array, ParameterTypes = new[] { ContractParameterType.String }, ParameterNames = new[] { "configKey" })]
171	private StackItem GetConfig(ApplicationEngine engine, Array args)
172	{	12✔
173	StoreView snapshot = engine.Snapshot;	12✔
174	string key = args[0].GetString();	12✔
175	return GetConfig(snapshot, key);	12✔
176	}	12✔
177
178	/// <summary>
179	/// Get HttpConfig
180	/// </summary>
181	/// <param name="snapshot">snapshot</param>
182	/// <param name="key">key</param>
183	/// <returns>value</returns>
184	public ByteArray GetConfig(StoreView snapshot, string key)
185	{	12✔
186	StorageItem storage = snapshot.Storages.GetAndChange(CreateStorageKey(Prefix_HttpConfig, Encoding.UTF8.GetBytes(key)));	12✔
187	return storage.Value;	12✔
188	}	12✔
189
190	/// <summary>
191	/// Set PerRequestFee
192	/// </summary>
193	/// <param name="engine">VM</param>
194	/// <param name="args">Parameter Array</param>
195	/// <returns>Returns true if the execution is successful, otherwise returns false</returns>
196	[ContractMethod(0_03000000, ContractParameterType.Boolean, ParameterTypes = new[] { ContractParameterType.Integer }, ParameterNames = new[] { "fee" })]
197	private StackItem SetPerRequestFee(ApplicationEngine engine, Array args)
198	{	18✔
199	StoreView snapshot = engine.Snapshot;	18✔
200	UInt160 account = GetOracleMultiSigAddress(snapshot);	18✔
201	if (!InteropService.Runtime.CheckWitnessInternal(engine, account)) return false;	24✔
202	int perRequestFee = (int)args[0].GetBigInteger();	12✔
203	if (perRequestFee <= 0) return false;	18✔
204	StorageItem storage = snapshot.Storages.GetAndChange(CreateStorageKey(Prefix_PerRequestFee));	6✔
205	storage.Value = BitConverter.GetBytes(perRequestFee);	6✔
206	return true;	6✔
207	}	18✔
208
209	/// <summary>
210	/// Get PerRequestFee
211	/// </summary>
212	/// <param name="engine">VM</param>
213	/// <param name="args">Parameter Array</param>
214	/// <returns>Value</returns>
215	[ContractMethod(0_01000000, ContractParameterType.Integer, SafeMethod = true)]
216	private StackItem GetPerRequestFee(ApplicationEngine engine, Array args)
217	{	12✔
218	return new Integer(GetPerRequestFee(engine.Snapshot));	12✔
219	}	12✔
220
221	/// <summary>
222	/// Get PerRequestFee
223	/// </summary>
224	/// <param name="snapshot">snapshot</param>
225	/// <returns>Value</returns>
226	public int GetPerRequestFee(StoreView snapshot)
227	{	12✔
228	return BitConverter.ToInt32(snapshot.Storages[CreateStorageKey(Prefix_PerRequestFee)].Value, 0);	12✔
229	}	12✔
230	}
231	}

neo-project / neo / 5fb501ad312ffe88b0644bd5bf4fecb3327a05e4-PR-1445

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