aboutsummaryrefslogtreecommitdiffhomepage
path: root/src/csharp/Grpc.Core/ServerCallContext.cs
blob: c8950b7677930782e7ab5e63136df96f6fe44a2a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
#region Copyright notice and license

// Copyright 2015, Google Inc.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
//     * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#endregion

using System;
using System.Threading;
using System.Threading.Tasks;

using Grpc.Core.Internal;

namespace Grpc.Core
{
    /// <summary>
    /// Context for a server-side call.
    /// </summary>
    public class ServerCallContext
    {
        private readonly CallSafeHandle callHandle;
        private readonly string method;
        private readonly string host;
        private readonly DateTime deadline;
        private readonly Metadata requestHeaders;
        private readonly CancellationToken cancellationToken;
        private readonly Metadata responseTrailers = new Metadata();

        private Status status = Status.DefaultSuccess;
        private Func<Metadata, Task> writeHeadersFunc;
        private IHasWriteOptions writeOptionsHolder;
        private Lazy<AuthContext> authContext;

        internal ServerCallContext(CallSafeHandle callHandle, string method, string host, DateTime deadline, Metadata requestHeaders, CancellationToken cancellationToken,
            Func<Metadata, Task> writeHeadersFunc, IHasWriteOptions writeOptionsHolder)
        {
            this.callHandle = callHandle;
            this.method = method;
            this.host = host;
            this.deadline = deadline;
            this.requestHeaders = requestHeaders;
            this.cancellationToken = cancellationToken;
            this.writeHeadersFunc = writeHeadersFunc;
            this.writeOptionsHolder = writeOptionsHolder;
            this.authContext = new Lazy<AuthContext>(GetAuthContextEager);
        }

        /// <summary>
        /// Asynchronously sends response headers for the current call to the client. This method may only be invoked once for each call and needs to be invoked
        /// before any response messages are written. Writing the first response message implicitly sends empty response headers if <c>WriteResponseHeadersAsync</c> haven't
        /// been called yet.
        /// </summary>
        /// <param name="responseHeaders">The response headers to send.</param>
        /// <returns>The task that finished once response headers have been written.</returns>
        public Task WriteResponseHeadersAsync(Metadata responseHeaders)
        {
            return writeHeadersFunc(responseHeaders);
        }

        /// <summary>
        /// Creates a propagation token to be used to propagate call context to a child call.
        /// </summary>
        public ContextPropagationToken CreatePropagationToken(ContextPropagationOptions options = null)
        {
            return new ContextPropagationToken(callHandle, deadline, cancellationToken, options);
        }
            
        /// <summary>Name of method called in this RPC.</summary>
        public string Method
        {
            get
            {
                return this.method;
            }
        }

        /// <summary>Name of host called in this RPC.</summary>
        public string Host
        {
            get
            {
                return this.host;
            }
        }

        /// <summary>Address of the remote endpoint in URI format.</summary>
        public string Peer
        {
            get
            {
                // Getting the peer lazily is fine as the native call is guaranteed
                // not to be disposed before user-supplied server side handler returns.
                // Most users won't need to read this field anyway.
                return this.callHandle.GetPeer();
            }
        }

        /// <summary>Deadline for this RPC.</summary>
        public DateTime Deadline
        {
            get
            {
                return this.deadline;
            }
        }

        /// <summary>Initial metadata sent by client.</summary>
        public Metadata RequestHeaders
        {
            get
            {
                return this.requestHeaders;
            }
        }

        /// <summary>Cancellation token signals when call is cancelled.</summary>
        public CancellationToken CancellationToken
        {
            get
            {
                return this.cancellationToken;
            }
        }

        /// <summary>Trailers to send back to client after RPC finishes.</summary>
        public Metadata ResponseTrailers
        {
            get
            {
                return this.responseTrailers;
            }
        }

        /// <summary> Status to send back to client after RPC finishes.</summary>
        public Status Status
        {
            get
            {
                return this.status;
            }

            set
            {
                status = value;
            }
        }

        /// <summary>
        /// Allows setting write options for the following write.
        /// For streaming response calls, this property is also exposed as on IServerStreamWriter for convenience.
        /// Both properties are backed by the same underlying value.
        /// </summary>
        public WriteOptions WriteOptions
        {
            get
            {
                return writeOptionsHolder.WriteOptions;
            }

            set
            {
                writeOptionsHolder.WriteOptions = value;
            }
        }

        /// <summary>
        /// Gets the <c>AuthContext</c> associated with this call.
        /// Note: Access to AuthContext is an experimental API that can change without any prior notice.
        /// </summary>
        public AuthContext AuthContext
        {
            get
            {
                return authContext.Value;
            }
        }

        private AuthContext GetAuthContextEager()
        {
            using (var authContextNative = callHandle.GetAuthContext())
            {
                return authContextNative.ToAuthContext();
            }
        }
    }

    /// <summary>
    /// Allows sharing write options between ServerCallContext and other objects.
    /// </summary>
    public interface IHasWriteOptions
    {
        /// <summary>
        /// Gets or sets the write options.
        /// </summary>
        WriteOptions WriteOptions { get; set; }
    }
}