| | | 1 | | // Copyright (c) ZeroC, Inc. |
| | | 2 | | |
| | | 3 | | using IceRpc.Slice.Ice; |
| | | 4 | | using Microsoft.Extensions.Logging; |
| | | 5 | | |
| | | 6 | | namespace IceRpc.Locator.Internal; |
| | | 7 | | |
| | | 8 | | /// <summary>Provides extension methods for <see cref="ILogger" />. They are used by <see |
| | | 9 | | /// cref="LogServerAddressFinderDecorator"/>.</summary> |
| | | 10 | | internal static partial class ServerAddressFinderLoggerExtensions |
| | | 11 | | { |
| | | 12 | | [LoggerMessage( |
| | | 13 | | EventId = (int)LocationEventId.FindFailed, |
| | | 14 | | EventName = nameof(LocationEventId.FindFailed), |
| | | 15 | | Level = LogLevel.Trace, |
| | | 16 | | Message = "Failed to find {LocationKind} '{Location}'")] |
| | | 17 | | internal static partial void LogFindFailed( |
| | | 18 | | this ILogger logger, |
| | | 19 | | string locationKind, |
| | | 20 | | Location location); |
| | | 21 | | |
| | | 22 | | [LoggerMessage( |
| | | 23 | | EventId = (int)LocationEventId.Found, |
| | | 24 | | EventName = nameof(LocationEventId.Found), |
| | | 25 | | Level = LogLevel.Trace, |
| | | 26 | | Message = "Found {LocationKind} '{Location}' = '{ServiceAddress}'")] |
| | | 27 | | internal static partial void LogFound( |
| | | 28 | | this ILogger logger, |
| | | 29 | | string locationKind, |
| | | 30 | | Location location, |
| | | 31 | | ServiceAddress serviceAddress); |
| | | 32 | | } |
| | | 33 | | |
| | | 34 | | /// <summary>A server address finder finds the server address(es) of a location. These server address(es) are carried by |
| | | 35 | | /// a dummy service address. When this dummy service address is not null, its ServerAddress property is guaranteed to be |
| | | 36 | | /// not <see langword="null" />. Unlike <see cref="ILocationResolver" />, a server address finder does not provide |
| | | 37 | | /// cache-related parameters and typically does not maintain a cache.</summary> |
| | | 38 | | internal interface IServerAddressFinder |
| | | 39 | | { |
| | | 40 | | Task<ServiceAddress?> FindAsync(Location location, CancellationToken cancellationToken); |
| | | 41 | | } |
| | | 42 | | |
| | | 43 | | /// <summary>The main implementation of IServerAddressFinder. It uses an <see cref="ILocator"/> to "find" the server |
| | | 44 | | /// addresses.</summary> |
| | | 45 | | internal class LocatorServerAddressFinder : IServerAddressFinder |
| | | 46 | | { |
| | | 47 | | private readonly ILocator _locator; |
| | | 48 | | |
| | | 49 | | public async Task<ServiceAddress?> FindAsync(Location location, CancellationToken cancellationToken) |
| | | 50 | | { |
| | | 51 | | if (location.IsAdapterId) |
| | | 52 | | { |
| | | 53 | | try |
| | | 54 | | { |
| | | 55 | | ServiceAddress? serviceAddress = await _locator.FindAdapterByIdAsync( |
| | | 56 | | location.Value, |
| | | 57 | | cancellationToken: cancellationToken).ConfigureAwait(false); |
| | | 58 | | |
| | | 59 | | if (serviceAddress is not null) |
| | | 60 | | { |
| | | 61 | | return serviceAddress.Protocol == Protocol.Ice && serviceAddress.ServerAddress is not null ? |
| | | 62 | | serviceAddress : |
| | | 63 | | throw new InvalidDataException( |
| | | 64 | | $"The locator returned invalid service address '{serviceAddress}' when looking up an adapter |
| | | 65 | | } |
| | | 66 | | else |
| | | 67 | | { |
| | | 68 | | return null; |
| | | 69 | | } |
| | | 70 | | } |
| | | 71 | | catch (AdapterNotFoundException) |
| | | 72 | | { |
| | | 73 | | // We treat AdapterNotFoundException just like a null return value. |
| | | 74 | | return null; |
| | | 75 | | } |
| | | 76 | | } |
| | | 77 | | else |
| | | 78 | | { |
| | | 79 | | try |
| | | 80 | | { |
| | | 81 | | ServiceAddress? serviceAddress = await _locator.FindObjectByIdAsync( |
| | | 82 | | location.Value, |
| | | 83 | | cancellationToken: cancellationToken).ConfigureAwait(false); |
| | | 84 | | |
| | | 85 | | if (serviceAddress is not null) |
| | | 86 | | { |
| | | 87 | | // findObjectById can return an indirect service address with an adapter ID |
| | | 88 | | return serviceAddress.Protocol == Protocol.Ice && |
| | | 89 | | (serviceAddress.ServerAddress is not null || serviceAddress.Params.ContainsKey("adapter-id")) ? |
| | | 90 | | serviceAddress : |
| | | 91 | | throw new InvalidDataException( |
| | | 92 | | $"The locator returned invalid service address '{serviceAddress}' when looking up an obj |
| | | 93 | | } |
| | | 94 | | else |
| | | 95 | | { |
| | | 96 | | return null; |
| | | 97 | | } |
| | | 98 | | } |
| | | 99 | | catch (ObjectNotFoundException) |
| | | 100 | | { |
| | | 101 | | // We treat ObjectNotFoundException just like a null return value. |
| | | 102 | | return null; |
| | | 103 | | } |
| | | 104 | | } |
| | | 105 | | } |
| | | 106 | | |
| | | 107 | | internal LocatorServerAddressFinder(ILocator locator) => _locator = locator; |
| | | 108 | | } |
| | | 109 | | |
| | | 110 | | /// <summary>A decorator that adds logging to a server address finder.</summary> |
| | | 111 | | internal class LogServerAddressFinderDecorator : IServerAddressFinder |
| | | 112 | | { |
| | | 113 | | private readonly IServerAddressFinder _decoratee; |
| | | 114 | | private readonly ILogger _logger; |
| | | 115 | | |
| | | 116 | | public async Task<ServiceAddress?> FindAsync(Location location, CancellationToken cancellationToken) |
| | | 117 | | { |
| | | 118 | | // We don't log any exceptions here because we expect another decorator further up in chain to log these |
| | | 119 | | // exceptions. |
| | | 120 | | ServiceAddress? serviceAddress = await _decoratee.FindAsync(location, cancellationToken).ConfigureAwait(false); |
| | | 121 | | if (serviceAddress is not null) |
| | | 122 | | { |
| | | 123 | | _logger.LogFound(location.Kind, location, serviceAddress); |
| | | 124 | | } |
| | | 125 | | else |
| | | 126 | | { |
| | | 127 | | _logger.LogFindFailed(location.Kind, location); |
| | | 128 | | } |
| | | 129 | | return serviceAddress; |
| | | 130 | | } |
| | | 131 | | |
| | | 132 | | internal LogServerAddressFinderDecorator(IServerAddressFinder decoratee, ILogger logger) |
| | | 133 | | { |
| | | 134 | | _decoratee = decoratee; |
| | | 135 | | _logger = logger; |
| | | 136 | | } |
| | | 137 | | } |
| | | 138 | | |
| | | 139 | | /// <summary>A decorator that updates its server address cache after a call to its decoratee (e.g. remote locator). It |
| | | 140 | | /// needs to execute downstream from the Coalesce decorator.</summary> |
| | | 141 | | internal class CacheUpdateServerAddressFinderDecorator : IServerAddressFinder |
| | | 142 | | { |
| | | 143 | | private readonly IServerAddressFinder _decoratee; |
| | | 144 | | private readonly IServerAddressCache _serverAddressCache; |
| | | 145 | | |
| | | 146 | | public async Task<ServiceAddress?> FindAsync(Location location, CancellationToken cancellationToken) |
| | 3 | 147 | | { |
| | 3 | 148 | | ServiceAddress? serviceAddress = await _decoratee.FindAsync(location, cancellationToken).ConfigureAwait(false); |
| | | 149 | | |
| | 3 | 150 | | if (serviceAddress is not null) |
| | 2 | 151 | | { |
| | 2 | 152 | | _serverAddressCache.Set(location, serviceAddress); |
| | 2 | 153 | | } |
| | | 154 | | else |
| | 1 | 155 | | { |
| | 1 | 156 | | _serverAddressCache.Remove(location); |
| | 1 | 157 | | } |
| | 3 | 158 | | return serviceAddress; |
| | 3 | 159 | | } |
| | | 160 | | |
| | 3 | 161 | | internal CacheUpdateServerAddressFinderDecorator( |
| | 3 | 162 | | IServerAddressFinder decoratee, |
| | 3 | 163 | | IServerAddressCache serverAddressCache) |
| | 3 | 164 | | { |
| | 3 | 165 | | _serverAddressCache = serverAddressCache; |
| | 3 | 166 | | _decoratee = decoratee; |
| | 3 | 167 | | } |
| | | 168 | | } |
| | | 169 | | |
| | | 170 | | /// <summary>A decorator that detects multiple concurrent identical FindAsync and "coalesce" them to avoid overloading |
| | | 171 | | /// the decoratee (e.g. the remote locator).</summary> |
| | | 172 | | internal class CoalesceServerAddressFinderDecorator : IServerAddressFinder |
| | | 173 | | { |
| | | 174 | | private readonly IServerAddressFinder _decoratee; |
| | | 175 | | private readonly object _mutex = new(); |
| | | 176 | | private readonly Dictionary<Location, Task<ServiceAddress?>> _requests = new(); |
| | | 177 | | |
| | | 178 | | public Task<ServiceAddress?> FindAsync(Location location, CancellationToken cancellationToken) |
| | | 179 | | { |
| | | 180 | | Task<ServiceAddress?>? task; |
| | | 181 | | |
| | | 182 | | lock (_mutex) |
| | | 183 | | { |
| | | 184 | | if (!_requests.TryGetValue(location, out task)) |
| | | 185 | | { |
| | | 186 | | // If there is no request in progress, we invoke one and cache the request to prevent concurrent |
| | | 187 | | // identical requests. It's removed once the response is received. |
| | | 188 | | task = PerformFindAsync(); |
| | | 189 | | |
| | | 190 | | if (!task.IsCompleted) |
| | | 191 | | { |
| | | 192 | | // If PerformFindAsync completed, don't add the task (it would leak since PerformFindAsync |
| | | 193 | | // is responsible for removing it). |
| | | 194 | | // Since PerformFindAsync locks _mutex in its finally block, the only way it can |
| | | 195 | | // be completed now is if completed synchronously. |
| | | 196 | | _requests.Add(location, task); |
| | | 197 | | } |
| | | 198 | | } |
| | | 199 | | } |
| | | 200 | | |
| | | 201 | | return task.WaitAsync(cancellationToken); |
| | | 202 | | |
| | | 203 | | async Task<ServiceAddress?> PerformFindAsync() |
| | | 204 | | { |
| | | 205 | | try |
| | | 206 | | { |
| | | 207 | | return await _decoratee.FindAsync(location, cancellationToken).ConfigureAwait(false); |
| | | 208 | | } |
| | | 209 | | finally |
| | | 210 | | { |
| | | 211 | | lock (_mutex) |
| | | 212 | | { |
| | | 213 | | _requests.Remove(location); |
| | | 214 | | } |
| | | 215 | | } |
| | | 216 | | } |
| | | 217 | | } |
| | | 218 | | |
| | | 219 | | internal CoalesceServerAddressFinderDecorator(IServerAddressFinder decoratee) => |
| | | 220 | | _decoratee = decoratee; |
| | | 221 | | } |