aboutsummaryrefslogtreecommitdiff
path: root/mod/tenant-service.hxx
blob: 48f525ab31add2244bd8a3456f0c4afb22bd0852 (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
// file      : mod/tenant-service.hxx -*- C++ -*-
// license   : MIT; see accompanying LICENSE file

#ifndef MOD_TENANT_SERVICE_HXX
#define MOD_TENANT_SERVICE_HXX

#include <map>

#include <libbrep/types.hxx>
#include <libbrep/utility.hxx>

#include <libbrep/build.hxx>

#include <mod/diagnostics.hxx>

namespace brep
{
  class tenant_service_base
  {
  public:
    virtual ~tenant_service_base () = default;
  };

  // Possible build notifications (see also the unloaded special notification
  // below):
  //
  // queued
  // building
  // built
  //
  // Possible transitions:
  //
  //          -> queued
  // queued   -> building
  // building -> queued   (interrupted & re-queued due to higher priority task)
  // building -> built
  // built    -> queued   (periodic or user-forced rebuild)
  //
  // While the implementation tries to make sure the notifications arrive in
  // the correct order, this is currently done by imposing delays (some
  // natural, such as building->built, and some artificial, such as
  // queued->building). As result, it is unlikely but possible to be notified
  // about the state transitions in the wrong order, especially if the
  // notifications take a long time. To minimize the chance of this happening,
  // the service implementation should strive to batch the queued state
  // notifications (or which there could be hundreds) in a single request if
  // at all possible. Also, if supported by the third-party API, it makes
  // sense for the implementation to protect against overwriting later states
  // with earlier. For example, if it's possible to place a condition on a
  // notification, it makes sense to only set the state to queued if none of
  // the later states (e.g., building) are already in effect.
  //
  // Note also that it's possible for the build to get deleted at any stage
  // without any further notifications. This can happen, for example, due to
  // data retention timeout or because the build configuration (buildtab
  // entry) is no longer present. There is no explicit `deleted` transition
  // notification because such situations (i.e., when a notification sequence
  // is abandoned half way) are not expected to arise ordinarily in a
  // properly-configured brep instance. And the third-party service is
  // expected to deal with them using some overall timeout/expiration
  // mechanism which it presumably has.
  //
  // Each build notification is in its own interface since a service may not
  // be interested in all of them while computing the information to pass is
  // expensive.

  class tenant_service_build_queued: public virtual tenant_service_base
  {
  public:
    // If the returned function is not NULL, it is called to update the
    // service data. It should return the new data or nullopt if no update is
    // necessary. Note: tenant_service::data passed to the callback and to the
    // returned function may not be the same. Also, the returned function may
    // be called multiple times (on transaction retries).
    //
    // The passed initial_state indicates the logical initial state and is
    // either absent, `building` (interrupted), or `built` (rebuild). Note
    // that all the passed build objects are for the same package version and
    // have the same initial state.
    //
    // The implementation of this and the below functions should normally not
    // need to make any decisions based on the passed build::state. Rather,
    // the function name suffix (_queued, _building, _built) signify the
    // logical end state.
    //
    // The build_queued_hints can be used to omit certain components from the
    // build id. If single_package_version is true, then this tenant contains
    // a single (non-test) package version and this package name and package
    // version can be omitted. If single_package_config is true, then the
    // package version being built only has the default package configuration
    // and thus it can be omitted.
    //
    struct build_queued_hints
    {
      bool single_package_version;
      bool single_package_config;
    };

    virtual function<optional<string> (const tenant_service&)>
    build_queued (const tenant_service&,
                  const vector<build>&,
                  optional<build_state> initial_state,
                  const build_queued_hints&,
                  const diag_epilogue& log_writer) const noexcept = 0;
  };

  class tenant_service_build_building: public virtual tenant_service_base
  {
  public:
    virtual function<optional<string> (const tenant_service&)>
    build_building (const tenant_service&,
                    const build&,
                    const diag_epilogue& log_writer) const noexcept = 0;
  };

  class tenant_service_build_built: public virtual tenant_service_base
  {
  public:
    virtual function<optional<string> (const tenant_service&)>
    build_built (const tenant_service&,
                 const build&,
                 const diag_epilogue& log_writer) const noexcept = 0;
  };

  // This notification is only made on unloaded CI requests created with the
  // ci_start::create() call and until they are loaded with ci_start::load()
  // or, alternatively, abandoned with ci_start::abandon().
  //
  class tenant_service_build_unloaded: public virtual tenant_service_base
  {
  public:
    virtual function<optional<string> (const tenant_service&)>
    build_unloaded (tenant_service&&,
                    const diag_epilogue& log_writer) const noexcept = 0;
  };

  // Map of service type (tenant_service::type) to service.
  //
  using tenant_service_map = std::map<string, shared_ptr<tenant_service_base>>;

  // Every notification callback function that needs to produce any
  // diagnostics shall begin with:
  //
  // NOTIFICATION_DIAG (log_writer);
  //
  // This will instantiate the error, warn, info, and trace diagnostics
  // streams with the function's name.
  //
  // Note that a callback function is not expected to throw any exceptions.
  // This is, in particular, why this macro doesn't instantiate the fail
  // diagnostics stream.
  //
#define NOTIFICATION_DIAG(log_writer)                                   \
  const basic_mark error (severity::error,                              \
                          log_writer,                                   \
                          __PRETTY_FUNCTION__);                         \
  const basic_mark warn (severity::warning,                             \
                         log_writer,                                    \
                         __PRETTY_FUNCTION__);                          \
  const basic_mark info (severity::info,                                \
                         log_writer,                                    \
                         __PRETTY_FUNCTION__);                          \
  const basic_mark trace (severity::trace,                              \
                          log_writer,                                   \
                          __PRETTY_FUNCTION__)
}

#endif // MOD_TENANT_SERVICE_HXX