| | | 1 | | // Copyright (c) Microsoft Corporation. All rights reserved. |
| | | 2 | | // Licensed under the MIT License. |
| | | 3 | | |
| | | 4 | | using System; |
| | | 5 | | using System.ComponentModel; |
| | | 6 | | using System.Globalization; |
| | | 7 | | using Azure.Core; |
| | | 8 | | |
| | | 9 | | namespace Azure.Messaging.EventHubs.Consumer |
| | | 10 | | { |
| | | 11 | | /// <summary> |
| | | 12 | | /// The position of events in an Event Hub partition, typically used in the creation of |
| | | 13 | | /// an <see cref="EventHubConsumerClient" />. |
| | | 14 | | /// </summary> |
| | | 15 | | /// |
| | | 16 | | public struct EventPosition : IEquatable<EventPosition> |
| | | 17 | | { |
| | | 18 | | /// <summary>The token that represents the beginning event in the stream of a partition.</summary> |
| | | 19 | | private const string StartOfStreamOffset = "-1"; |
| | | 20 | | |
| | | 21 | | /// <summary>The token that represents the last event in the stream of a partition.</summary> |
| | | 22 | | private const string EndOfStreamOffset = "@latest"; |
| | | 23 | | |
| | | 24 | | /// <summary> |
| | | 25 | | /// Corresponds to the location of the first event present in the partition. Use this |
| | | 26 | | /// position to begin receiving from the first event that was enqueued in the partition |
| | | 27 | | /// which has not expired due to the retention policy. |
| | | 28 | | /// </summary> |
| | | 29 | | /// |
| | 660 | 30 | | public static EventPosition Earliest => FromOffset(StartOfStreamOffset, false); |
| | | 31 | | |
| | | 32 | | /// <summary> |
| | | 33 | | /// Corresponds to the end of the partition, where no more events are currently enqueued. Use this |
| | | 34 | | /// position to begin receiving from the next event to be enqueued in the partition after an <see cref="EventH |
| | | 35 | | /// is created with this position. |
| | | 36 | | /// </summary> |
| | | 37 | | /// |
| | 38 | 38 | | public static EventPosition Latest => FromOffset(EndOfStreamOffset, false); |
| | | 39 | | |
| | | 40 | | /// <summary> |
| | | 41 | | /// The offset of the event identified by this position. |
| | | 42 | | /// </summary> |
| | | 43 | | /// |
| | | 44 | | /// <value>Expected to be <c>null</c> if the event position represents a sequence number or enqueue time.</value |
| | | 45 | | /// |
| | | 46 | | /// <remarks> |
| | | 47 | | /// The offset is the relative position for event in the context of the stream. The offset |
| | | 48 | | /// should not be considered a stable value, as the same offset may refer to a different event |
| | | 49 | | /// as events reach the age limit for retention and are no longer visible within the stream. |
| | | 50 | | /// </remarks> |
| | | 51 | | /// |
| | 1364 | 52 | | internal string Offset { get; set; } |
| | | 53 | | |
| | | 54 | | /// <summary> |
| | | 55 | | /// Indicates if the specified offset is inclusive of the event which it identifies. This |
| | | 56 | | /// information is only relevant if the event position was identified by an offset or sequence number. |
| | | 57 | | /// </summary> |
| | | 58 | | /// |
| | | 59 | | /// <value><c>true</c> if the offset is inclusive; otherwise, <c>false</c>.</value> |
| | | 60 | | /// |
| | 1198 | 61 | | internal bool IsInclusive { get; set; } |
| | | 62 | | |
| | | 63 | | /// <summary> |
| | | 64 | | /// The enqueue time of the event identified by this position. |
| | | 65 | | /// </summary> |
| | | 66 | | /// |
| | | 67 | | /// <value>Expected to be <c>null</c> if the event position represents an offset or sequence number.</value> |
| | | 68 | | /// |
| | 330 | 69 | | internal DateTimeOffset? EnqueuedTime { get; set; } |
| | | 70 | | |
| | | 71 | | /// <summary> |
| | | 72 | | /// The sequence number of the event identified by this position. |
| | | 73 | | /// </summary> |
| | | 74 | | /// |
| | | 75 | | /// <value>Expected to be <c>null</c> if the event position represents an offset or enqueue time.</value> |
| | | 76 | | /// |
| | 384 | 77 | | internal long? SequenceNumber { get; set; } |
| | | 78 | | |
| | | 79 | | /// <summary> |
| | | 80 | | /// Corresponds to the event in the partition at the provided offset, inclusive of that event. |
| | | 81 | | /// </summary> |
| | | 82 | | /// |
| | | 83 | | /// <param name="offset">The offset of an event with respect to its relative position in the partition.</param> |
| | | 84 | | /// <param name="isInclusive">If true, the event with the <paramref name="offset"/> is included; otherwise the n |
| | | 85 | | /// |
| | | 86 | | /// <returns>The position of the specified event.</returns> |
| | | 87 | | /// |
| | | 88 | | public static EventPosition FromOffset(long offset, |
| | 146 | 89 | | bool isInclusive = true) => FromOffset(offset.ToString(CultureInfo.Invari |
| | | 90 | | |
| | | 91 | | /// <summary> |
| | | 92 | | /// Corresponds to the event in the partition having a specified sequence number associated with it. |
| | | 93 | | /// </summary> |
| | | 94 | | /// |
| | | 95 | | /// <param name="sequenceNumber">The sequence number assigned to an event when it was enqueued in the partition. |
| | | 96 | | /// <param name="isInclusive">If true, the event with the <paramref name="sequenceNumber"/> is included; otherwi |
| | | 97 | | /// |
| | | 98 | | /// <returns>The position of the specified event.</returns> |
| | | 99 | | /// |
| | | 100 | | public static EventPosition FromSequenceNumber(long sequenceNumber, |
| | | 101 | | bool isInclusive = true) |
| | | 102 | | { |
| | 44 | 103 | | return new EventPosition |
| | 44 | 104 | | { |
| | 44 | 105 | | SequenceNumber = sequenceNumber, |
| | 44 | 106 | | IsInclusive = isInclusive |
| | 44 | 107 | | }; |
| | | 108 | | } |
| | | 109 | | |
| | | 110 | | /// <summary> |
| | | 111 | | /// Corresponds to a specific date and time within the partition to begin seeking an event; the event enqueued |
| | | 112 | | /// requested <paramref name="enqueuedTime" /> will become the current position. |
| | | 113 | | /// </summary> |
| | | 114 | | /// |
| | | 115 | | /// <param name="enqueuedTime">The date and time, in UTC, from which the next available event should be chosen.< |
| | | 116 | | /// |
| | | 117 | | /// <returns>The position of the specified event.</returns> |
| | | 118 | | /// |
| | | 119 | | public static EventPosition FromEnqueuedTime(DateTimeOffset enqueuedTime) |
| | | 120 | | { |
| | 16 | 121 | | return new EventPosition |
| | 16 | 122 | | { |
| | 16 | 123 | | EnqueuedTime = enqueuedTime |
| | 16 | 124 | | }; |
| | | 125 | | } |
| | | 126 | | |
| | | 127 | | /// <summary> |
| | | 128 | | /// Determines whether the specified <see cref="EventPosition" /> is equal to this instance. |
| | | 129 | | /// </summary> |
| | | 130 | | /// |
| | | 131 | | /// <param name="other">The <see cref="EventPosition" /> to compare with this instance.</param> |
| | | 132 | | /// |
| | | 133 | | /// <returns><c>true</c> if the specified <see cref="EventPosition" /> is equal to this instance; otherwise, <c> |
| | | 134 | | /// |
| | | 135 | | public bool Equals(EventPosition other) |
| | | 136 | | { |
| | 180 | 137 | | return (Offset == other.Offset) |
| | 180 | 138 | | && (SequenceNumber == other.SequenceNumber) |
| | 180 | 139 | | && (EnqueuedTime == other.EnqueuedTime) |
| | 180 | 140 | | && (IsInclusive == other.IsInclusive); |
| | | 141 | | } |
| | | 142 | | |
| | | 143 | | /// <summary> |
| | | 144 | | /// Determines whether the specified <see cref="System.Object" /> is equal to this instance. |
| | | 145 | | /// </summary> |
| | | 146 | | /// |
| | | 147 | | /// <param name="obj">The <see cref="System.Object" /> to compare with this instance.</param> |
| | | 148 | | /// |
| | | 149 | | /// <returns><c>true</c> if the specified <see cref="System.Object" /> is equal to this instance; otherwise, <c> |
| | | 150 | | /// |
| | | 151 | | [EditorBrowsable(EditorBrowsableState.Never)] |
| | | 152 | | public override bool Equals(object obj) => |
| | 64 | 153 | | obj switch |
| | 64 | 154 | | { |
| | 128 | 155 | | EventPosition other => Equals(other), |
| | 0 | 156 | | _ => false |
| | 64 | 157 | | }; |
| | | 158 | | |
| | | 159 | | /// <summary> |
| | | 160 | | /// Returns a hash code for this instance. |
| | | 161 | | /// </summary> |
| | | 162 | | /// |
| | | 163 | | /// <returns>A hash code for this instance, suitable for use in hashing algorithms and data structures like a ha |
| | | 164 | | /// |
| | | 165 | | [EditorBrowsable(EditorBrowsableState.Never)] |
| | | 166 | | public override int GetHashCode() |
| | | 167 | | { |
| | 4 | 168 | | var hashCode = new HashCodeBuilder(); |
| | 4 | 169 | | hashCode.Add(Offset); |
| | 4 | 170 | | hashCode.Add(SequenceNumber); |
| | 4 | 171 | | hashCode.Add(EnqueuedTime); |
| | 4 | 172 | | hashCode.Add(IsInclusive); |
| | | 173 | | |
| | 4 | 174 | | return hashCode.ToHashCode(); |
| | | 175 | | } |
| | | 176 | | |
| | | 177 | | /// <summary> |
| | | 178 | | /// Converts the instance to string representation. |
| | | 179 | | /// </summary> |
| | | 180 | | /// |
| | | 181 | | /// <returns>A <see cref="System.String" /> that represents this instance.</returns> |
| | | 182 | | /// |
| | | 183 | | [EditorBrowsable(EditorBrowsableState.Never)] |
| | | 184 | | public override string ToString() => |
| | | 185 | | this switch |
| | | 186 | | { |
| | 122 | 187 | | EventPosition _ when (Offset == StartOfStreamOffset) => nameof(Earliest), |
| | 16 | 188 | | EventPosition _ when (Offset == EndOfStreamOffset) => nameof(Latest), |
| | 18 | 189 | | EventPosition _ when (!string.IsNullOrEmpty(Offset)) => $"Offset: [{ Offset }] | Inclusive: [{ IsInclusi |
| | 10 | 190 | | EventPosition _ when (SequenceNumber.HasValue) => $"Sequence Number: [{ SequenceNumber }] | Inclusive: [ |
| | 4 | 191 | | EventPosition _ when (EnqueuedTime.HasValue) => $"Enqueued: [{ EnqueuedTime }]", |
| | 0 | 192 | | _ => base.ToString() |
| | | 193 | | }; |
| | | 194 | | |
| | | 195 | | /// <summary> |
| | | 196 | | /// Corresponds to the event in the partition at the provided offset. |
| | | 197 | | /// </summary> |
| | | 198 | | /// |
| | | 199 | | /// <param name="offset">The offset of an event with respect to its relative position in the partition.</param> |
| | | 200 | | /// <param name="isInclusive">If true, the event at the <paramref name="offset"/> is included; otherwise the nex |
| | | 201 | | /// |
| | | 202 | | /// <returns>The position of the specified event.</returns> |
| | | 203 | | /// |
| | | 204 | | private static EventPosition FromOffset(string offset, |
| | | 205 | | bool isInclusive) |
| | | 206 | | { |
| | 844 | 207 | | Argument.AssertNotNullOrWhiteSpace(nameof(offset), offset); |
| | | 208 | | |
| | 844 | 209 | | return new EventPosition |
| | 844 | 210 | | { |
| | 844 | 211 | | Offset = offset, |
| | 844 | 212 | | IsInclusive = isInclusive |
| | 844 | 213 | | }; |
| | | 214 | | } |
| | | 215 | | |
| | | 216 | | /// <summary> |
| | | 217 | | /// Determines whether the specified <see cref="EventPosition" /> instances are equal to each other. |
| | | 218 | | /// </summary> |
| | | 219 | | /// |
| | | 220 | | /// <param name="left">The first <see cref="EventPosition" /> to consider.</param> |
| | | 221 | | /// <param name="right">The second <see cref="EventPosition" /> to consider.</param> |
| | | 222 | | /// |
| | | 223 | | /// <returns><c>true</c> if the two specified <see cref="EventPosition" /> instances are equal; otherwise, <c>fa |
| | | 224 | | /// |
| | | 225 | | public static bool operator ==(EventPosition left, |
| | 58 | 226 | | EventPosition right) => left.Equals(right); |
| | | 227 | | |
| | | 228 | | /// <summary> |
| | | 229 | | /// Determines whether the specified <see cref="EventPosition" /> instances are not equal to each other. |
| | | 230 | | /// </summary> |
| | | 231 | | /// |
| | | 232 | | /// <param name="left">The first <see cref="EventPosition" /> to consider.</param> |
| | | 233 | | /// <param name="right">The second <see cref="EventPosition" /> to consider.</param> |
| | | 234 | | /// |
| | | 235 | | /// <returns><c>true</c> if the two specified <see cref="EventPosition" /> instances are not equal; otherwise, < |
| | | 236 | | /// |
| | | 237 | | public static bool operator !=(EventPosition left, |
| | 22 | 238 | | EventPosition right) => (!left.Equals(right)); |
| | | 239 | | } |
| | | 240 | | } |