Mercurial > hg > orthanc-book
annotate Sphinx/source/plugins/python.rst @ 373:847996394688
Scheduling a task for periodic execution
author | Sebastien Jodogne <s.jodogne@gmail.com> |
---|---|
date | Sun, 05 Apr 2020 10:25:36 +0200 |
parents | 181b02cea7ab |
children | f5bbdabb04d9 |
rev | line source |
---|---|
343
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
1 .. _python-plugin: |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
2 |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
3 |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
4 Python plugin for Orthanc |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
5 ========================= |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
6 |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
7 .. contents:: |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
8 |
364
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
9 Overview |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
10 -------- |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
11 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
12 This plugin can be used to write :ref:`Orthanc plugins |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
13 <creating-plugins>` using the `Python programming language |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
14 <https://en.wikipedia.org/wiki/Python_(programming_language)>`__ |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
15 instead of the more complex C/C++ programming languages. |
343
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
16 |
364
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
17 Python plugins have access to more features and a more consistent SDK |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
18 than :ref:`Lua scripts <lua>`. The Python API is automatically |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
19 generated from the `Orthanc plugin SDK in C |
345 | 20 <https://hg.orthanc-server.com/orthanc/file/Orthanc-1.5.7/Plugins/Include/orthanc/OrthancCPlugin.h>`__ |
21 using the `Clang <https://en.wikipedia.org/wiki/Clang>`__ compiler | |
364
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
22 front-end. |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
23 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
24 As of initial release 1.0 of the plugin, the coverage of the C SDK is |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
25 about 75% (105 functions are automatically wrapped in Python out of a |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
26 total of 139 functions in the Orthanc SDK 1.5.7). |
343
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
27 |
353 | 28 Licensing |
29 --------- | |
30 | |
31 Pay attention to the fact that this plugin is licensed under the terms | |
32 of the `AGPL license | |
33 <https://en.wikipedia.org/wiki/GNU_Affero_General_Public_License>`__. | |
34 | |
35 This has an important consequence: If you distribute Orthanc to | |
364
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
36 clients together with one Python script, or if you put an Orthanc |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
37 server equipped with one Python script on a Web portal, you **must** |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
38 disclose the source code of your Python script to the Orthanc |
354 | 39 community under the terms of the AGPL license. |
40 | |
41 We suggest you to put the source code of your Python scripts on the | |
42 dedicated `"OrthancContributed" repository on GitHub | |
43 <https://github.com/jodogne/OrthancContributed/tree/master/Plugins>`__, | |
44 and/or to send it to the `Orthanc Users | |
45 <https://groups.google.com/forum/#!forum/orthanc-users>`__ discussion | |
46 group. | |
353 | 47 |
48 Check out the :ref:`FAQ about licensing <licensing>` for more context. | |
49 | |
50 | |
364
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
51 Usage |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
52 ----- |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
53 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
54 Docker |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
55 ...... |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
56 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
57 .. highlight:: json |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
58 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
59 The most direct way of starting Orthanc together with the Python |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
60 plugin is through :ref:`Docker <docker>`. Let's create the file |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
61 ``/tmp/hello.py`` that contains the following basic Python script:: |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
62 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
63 print('Hello world!') |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
64 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
65 .. highlight:: json |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
66 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
67 Let's also create the file ``/tmp/orthanc.json`` that contains the |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
68 following minimal :ref:`configuration for Orthanc <configuration>`:: |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
69 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
70 { |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
71 "StorageDirectory" : "/var/lib/orthanc/db", |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
72 "RemoteAccessAllowed" : true, |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
73 "Plugins" : [ |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
74 "/usr/local/share/orthanc/plugins" |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
75 ], |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
76 "PythonScript" : "/etc/orthanc/hello.py" |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
77 } |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
78 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
79 .. highlight:: bash |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
80 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
81 Given these two files, Orthanc can be started as follows:: |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
82 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
83 $ docker run -p 4242:4242 -p 8042:8042 --rm \ |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
84 -v /tmp/orthanc.json:/etc/orthanc/orthanc.json:ro \ |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
85 -v /tmp/hello.py:/etc/orthanc/hello.py:ro \ |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
86 jodogne/orthanc-python |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
87 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
88 .. highlight:: text |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
89 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
90 You'll see the following excerpt in the log, which indicates that the Python plugin is properly loaded:: |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
91 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
92 W0331 15:48:12.990661 PluginsManager.cpp:269] Registering plugin 'python' (version mainline) |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
93 W0331 15:48:12.990691 PluginsManager.cpp:168] Python plugin is initializing |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
94 W0331 15:48:12.990743 PluginsManager.cpp:168] Using Python script "hello.py" from directory: /etc/orthanc |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
95 W0331 15:48:12.990819 PluginsManager.cpp:168] Program name: /usr/local/sbin/Orthanc |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
96 Hello world! |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
97 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
98 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
99 Compiling from source |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
100 ..................... |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
101 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
102 .. highlight:: bash |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
103 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
104 The procedure to compile this plugin from source is similar to that |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
105 for the :ref:`core of Orthanc <compiling>`. The following commands |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
106 should work for most UNIX-like distribution (including GNU/Linux):: |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
107 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
108 $ mkdir Build |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
109 $ cd Build |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
110 $ cmake .. -DPYTHON_VERSION=3.7 -DSTATIC_BUILD=ON -DCMAKE_BUILD_TYPE=Release |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
111 $ make |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
112 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
113 Before running CMake, make sure that the Python interpreter and its |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
114 associated development library are installed. On Ubuntu 18.04 LTS, you |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
115 would for instance install packages ``libpython3.7-dev`` and |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
116 ``python3.7``. |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
117 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
118 The compilation will produce the shared library ``OrthancPython``, |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
119 that can be loaded by properly setting the ``Plugins`` |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
120 :ref:`configuration option <configuration>` of Orthanc. |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
121 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
122 **Warning:** The shared library is only compatible with the Python |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
123 interpreter whose version corresponds to the value of the |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
124 ``PYTHON_VERSION`` argument that was given to CMake. |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
125 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
126 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
127 Microsoft Windows |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
128 ................. |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
129 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
130 Pre-compiled binaries for Microsoft Windows `are also available |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
131 <https://www.orthanc-server.com/browse.php?path=/plugin-python>`__. |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
132 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
133 Beware that one version of the Python plugin can only be run against |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
134 one version of the Python interpreter. This version is clearly |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
135 indicated in the name of the folder. |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
136 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
137 As of release 1.0, the Orthanc project only provides pre-compiled |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
138 binaries for Microsoft Windows 32bit and Python 2.7. Even though this |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
139 version of Python is not supported anymore, it can still run on all |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
140 the versions of Microsoft Windows that have been released for more |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
141 than 10 years. |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
142 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
143 .. highlight:: text |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
144 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
145 You are of course free to compile the plugin from sources if you need |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
146 a more recent version. You'll have to explicitly specify the path to |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
147 your Python installation while invoking CMake. For instance:: |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
148 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
149 C:\orthanc-python\Build> cmake .. -DPYTHON_VERSION=2.7 -DPYTHON_WINDOWS_ROOT=C:/Python27 \ |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
150 -DSTATIC_BUILD=ON -DCMAKE_BUILD_TYPE=Release -G "Visual Studio 15 2017" |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
151 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
152 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
153 Configuration options |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
154 --------------------- |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
155 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
156 The only two configuration options that are available for this plugin |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
157 are the following: |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
158 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
159 * ``PythonScript`` indicates where the Python script is located. If |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
160 this configuration option is not provided, the Python plugin is not |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
161 started. |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
162 |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
163 * ``PythonVerbose`` is a Boolean value to make the Python interpreter |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
164 verbose. |
234de55ed125
usage of the python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
354
diff
changeset
|
165 |
343
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
166 |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
167 Samples |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
168 ------- |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
169 |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
170 Extending the REST API |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
171 ...................... |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
172 |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
173 .. highlight:: python |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
174 |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
175 Here is a basic Python script that registers two new routes in the |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
176 REST API:: |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
177 |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
178 import orthanc |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
179 import pprint |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
180 |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
181 def OnRest(output, uri, **request): |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
182 pprint.pprint(request) |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
183 print('Accessing uri: %s' % uri) |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
184 output.AnswerBuffer('ok\n', 'text/plain') |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
185 |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
186 orthanc.RegisterRestCallback('/(to)(t)o', OnRest) |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
187 orthanc.RegisterRestCallback('/tata', OnRest) |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
188 |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
189 .. highlight:: json |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
190 |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
191 Here is the associated minimal configuration file for Orthanc |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
192 (provided the Python script is saved as ``rest.py``):: |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
193 |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
194 { |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
195 "Plugins" : [ "." ], |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
196 "PythonScript" : "rest.py", |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
197 "PythonVerbose" : false |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
198 } |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
199 |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
200 .. highlight:: bash |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
201 |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
202 The route can then be accessed as:: |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
203 |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
204 $ curl http://localhost:8042/toto |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
205 ok |
fff45618262d
creating the documentation of the Python plugin
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
|
206 |
345 | 207 |
208 Listening to changes | |
209 .................... | |
210 | |
346
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
211 .. highlight:: python |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
212 |
345 | 213 This sample uploads a DICOM file as soon as Orthanc is started:: |
214 | |
215 import orthanc | |
216 | |
217 def OnChange(changeType, level, resource): | |
218 if changeType == orthanc.ChangeType.ORTHANC_STARTED: | |
219 print('Started') | |
220 | |
221 with open('/tmp/sample.dcm', 'rb') as f: | |
222 orthanc.RestApiPost('/instances', f.read()) | |
223 | |
224 elif changeType == orthanc.ChangeType.ORTHANC_STOPPED: | |
225 print('Stopped') | |
226 | |
227 elif changeType == orthanc.ChangeType.NEW_INSTANCE: | |
228 print('A new instance was uploaded: %s' % resource) | |
229 | |
230 orthanc.RegisterOnChangeCallback(OnChange) | |
231 | |
232 | |
233 Accessing the content of a new instance | |
346
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
234 ....................................... |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
235 |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
236 .. highlight:: python |
345 | 237 |
238 :: | |
239 | |
240 import orthanc | |
241 import json | |
242 import pprint | |
243 | |
244 def OnStoredInstance(dicom, instanceId): | |
245 print('Received instance %s of size %d (transfer syntax %s, SOP class UID %s)' % ( | |
246 instanceId, dicom.GetInstanceSize(), | |
247 dicom.GetInstanceMetadata('TransferSyntax'), | |
248 dicom.GetInstanceMetadata('SopClassUid'))) | |
249 | |
250 # Print the origin information | |
251 if dicom.GetInstanceOrigin() == orthanc.InstanceOrigin.DICOM_PROTOCOL: | |
252 print('This instance was received through the DICOM protocol') | |
253 elif dicom.GetInstanceOrigin() == orthanc.InstanceOrigin.REST_API: | |
254 print('This instance was received through the REST API') | |
255 | |
256 # Print the DICOM tags | |
257 pprint.pprint(json.loads(dicom.GetInstanceSimplifiedJson())) | |
258 | |
259 orthanc.RegisterOnStoredInstanceCallback(OnStoredInstance) | |
346
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
260 |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
261 |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
262 Calling pydicom |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
263 ............... |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
264 |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
265 .. highlight:: python |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
266 |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
267 Here is a sample Python plugin that registers a REST callback to dump |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
268 the content of the dataset of one given DICOM instance stored in |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
269 Orthanc, using `pydicom <https://pydicom.github.io/>`__:: |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
270 |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
271 import io |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
272 import orthanc |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
273 import pydicom |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
274 |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
275 def DecodeInstance(output, uri, **request): |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
276 if request['method'] == 'GET': |
347 | 277 # Retrieve the instance ID from the regular expression (*) |
346
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
278 instanceId = request['groups'][0] |
347 | 279 # Get the content of the DICOM file |
346
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
280 f = orthanc.GetDicomForInstance(instanceId) |
347 | 281 # Parse it using pydicom |
346
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
282 dicom = pydicom.dcmread(io.BytesIO(f)) |
347 | 283 # Return a string representation the dataset to the caller |
346
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
284 output.AnswerBuffer(str(dicom), 'text/plain') |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
285 else: |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
286 output.SendMethodNotAllowed('GET') |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
287 |
347 | 288 orthanc.RegisterRestCallback('/pydicom/(.*)', DecodeInstance) # (*) |
346
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
289 |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
290 .. highlight:: bash |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
291 |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
292 This can be called as follows:: |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
293 |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
294 $ curl http://localhost:8042/pydicom/19816330-cb02e1cf-df3a8fe8-bf510623-ccefe9f5 |
bdf8757449e3
more python samples
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
345
diff
changeset
|
295 |
347 | 296 |
297 Auto-routing studies | |
298 .................... | |
299 | |
300 .. highlight:: python | |
301 | |
302 Here is a sample Python plugin that routes any :ref:`stable study | |
303 <lua-callbacks>` to a modality named ``samples`` (as declared in the | |
304 ``DicomModalities`` configuration option):: | |
305 | |
306 import orthanc | |
307 | |
308 def OnChange(changeType, level, resourceId): | |
309 if changeType == orthanc.ChangeType.STABLE_STUDY: | |
310 print('Stable study: %s' % resourceId) | |
311 orthanc.RestApiPost('/modalities/sample/store', resourceId) | |
312 | |
313 orthanc.RegisterOnChangeCallback(OnChange) | |
348 | 314 |
315 | |
352 | 316 Rendering a thumbnail using PIL/Pillow |
317 ...................................... | |
348 | 318 |
319 .. highlight:: python | |
320 | |
321 :: | |
322 | |
323 from PIL import Image | |
324 import io | |
325 import orthanc | |
326 | |
327 def DecodeInstance(output, uri, **request): | |
328 if request['method'] == 'GET': | |
329 # Retrieve the instance ID from the regular expression (*) | |
330 instanceId = request['groups'][0] | |
331 | |
332 # Render the instance, then open it in Python using PIL/Pillow | |
333 png = orthanc.RestApiGet('/instances/%s/rendered' % instanceId) | |
334 image = Image.open(io.BytesIO(png)) | |
335 | |
336 # Downsize the image as a 64x64 thumbnail | |
337 image.thumbnail((64, 64), Image.ANTIALIAS) | |
338 | |
339 # Save the thumbnail as JPEG, then send the buffer to the caller | |
340 jpeg = io.BytesIO() | |
341 image.save(jpeg, format = "JPEG", quality = 80) | |
342 jpeg.seek(0) | |
343 output.AnswerBuffer(jpeg.read(), 'text/plain') | |
344 | |
345 else: | |
346 output.SendMethodNotAllowed('GET') | |
347 | |
348 orthanc.RegisterRestCallback('/pydicom/(.*)', DecodeInstance) # (*) | |
351 | 349 |
350 | |
369
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
351 .. _python-introspection: |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
352 |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
353 Inspecting the available API |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
354 ............................ |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
355 |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
356 .. highlight:: python |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
357 |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
358 Thanks to Python's introspection primitives, it is possible to inspect |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
359 the API of the ``orthanc`` module in order to dump all the available |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
360 features:: |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
361 |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
362 import inspect |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
363 import numbers |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
364 import orthanc |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
365 |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
366 # Loop over the members of the "orthanc" module |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
367 for (name, obj) in inspect.getmembers(orthanc): |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
368 if inspect.isroutine(obj): |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
369 print('Function %s():\n Documentation: %s\n' % (name, inspect.getdoc(obj))) |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
370 |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
371 elif inspect.isclass(obj): |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
372 print('Class %s:\n Documentation: %s' % (name, inspect.getdoc(obj))) |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
373 |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
374 # Loop over the members of the class |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
375 for (subname, subobj) in inspect.getmembers(obj): |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
376 if isinstance(subobj, numbers.Number): |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
377 print(' - Enumeration value %s: %s' % (subname, subobj)) |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
378 elif (not subname.startswith('_') and |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
379 inspect.ismethoddescriptor(subobj)): |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
380 print(' - Method %s(): %s' % (subname, inspect.getdoc(subobj))) |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
381 print('') |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
382 |
373
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
383 |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
384 .. _python-scheduler: |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
385 |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
386 Scheduling a task for periodic execution |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
387 ........................................ |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
388 |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
389 .. highlight:: python |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
390 |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
391 The following Python script will periodically (every second) run the |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
392 function ``Hello()`` thanks to the ``threading`` module:: |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
393 |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
394 import orthanc |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
395 import threading |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
396 |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
397 TIMER = None |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
398 |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
399 def Hello(): |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
400 global TIMER |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
401 TIMER = None |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
402 orthanc.LogWarning("In Hello()") |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
403 # Do stuff... |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
404 TIMER = threading.Timer(1, Hello) # Re-schedule after 1 second |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
405 TIMER.start() |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
406 |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
407 def OnChange(changeType, level, resource): |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
408 if changeType == orthanc.ChangeType.ORTHANC_STARTED: |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
409 orthanc.LogWarning("Starting the scheduler") |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
410 Hello() |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
411 |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
412 elif changeType == orthanc.ChangeType.ORTHANC_STOPPED: |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
413 if TIMER != None: |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
414 orthanc.LogWarning("Stopping the scheduler") |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
415 TIMER.cancel() |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
416 |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
417 orthanc.RegisterOnChangeCallback(OnChange) |
847996394688
Scheduling a task for periodic execution
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
369
diff
changeset
|
418 |
369
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
419 |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
420 |
181b02cea7ab
inspecting Python API
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
364
diff
changeset
|
421 |
351 | 422 Performance and concurrency |
423 --------------------------- | |
424 | |
425 .. highlight:: python | |
426 | |
427 Let us consider the following sample Python script that makes a | |
428 CPU-intensive computation on a REST callback:: | |
429 | |
430 import math | |
431 import orthanc | |
432 import time | |
433 | |
434 # CPU-intensive computation taking about 4 seconds | |
435 def SlowComputation(): | |
436 start = time.time() | |
437 for i in range(1000): | |
438 for j in range(30000): | |
439 math.sqrt(float(j)) | |
440 end = time.time() | |
441 duration = (end - start) | |
442 return 'computation done in %.03f seconds\n' % duration | |
443 | |
444 def OnRest(output, uri, **request): | |
445 answer = SlowComputation() | |
446 output.AnswerBuffer(answer, 'text/plain') | |
447 | |
448 orthanc.RegisterRestCallback('/computation', OnRest) | |
449 | |
450 | |
451 .. highlight:: text | |
452 | |
453 Calling this REST route from the command-line returns the time that is | |
454 needed to compute 30 million times a squared root on your CPU:: | |
455 | |
456 $ curl http://localhost:8042/computation | |
457 computation done in 4.208 seconds | |
458 | |
459 Now, let us call this route three times concurrently (we use bash):: | |
460 | |
461 $ (curl http://localhost:8042/computation & curl http://localhost:8042/computation & curl http://localhost:8042/computation ) | |
462 computation done in 11.262 seconds | |
463 computation done in 12.457 seconds | |
464 computation done in 13.360 seconds | |
465 | |
466 As can be seen, the computation time has tripled. This means that the | |
467 computations were not distributed across the available CPU cores. | |
468 This might seem surprising, as Orthanc is a threaded server (in | |
469 Orthanc, a pool of C++ threads serves concurrent requests). | |
470 | |
471 The explanation is that the Python interpreter (`CPython | |
472 <https://en.wikipedia.org/wiki/CPython>`__ actually) is built on the | |
473 top of a so-called `Global Interpreter Lock (GIL) | |
474 <https://en.wikipedia.org/wiki/Global_interpreter_lock>`__. The GIL is | |
475 basically a mutex that protects all the calls to the Python | |
476 interpreter. If multiple C++ threads from Orthanc call a Python | |
353 | 477 callback, only one can proceed at any given time. Note however that |
478 the GIL only applies to the Python script: The baseline REST API of | |
479 Orthanc is not affected by the GIL. | |
351 | 480 |
481 .. highlight:: python | |
482 | |
483 The solution is to use the `multiprocessing primitives | |
484 <https://docs.python.org/3/library/multiprocessing.html>`__ of Python. | |
485 The "master" Python interpreter that is initially started by the | |
486 Orthanc plugin, can start several `children processes | |
487 <https://en.wikipedia.org/wiki/Process_(computing)>`__, each of these | |
488 processes running a separate Python interpreter. This allows to | |
489 offload intensive computations from the "master" Python interpreter of | |
490 Orthanc onto those "slave" interpreters. The ``multiprocessing`` | |
491 library is actually quite straightforward to use:: | |
492 | |
493 import math | |
494 import multiprocessing | |
495 import orthanc | |
496 import signal | |
497 import time | |
498 | |
499 # CPU-intensive computation taking about 4 seconds | |
500 # (same code as above) | |
501 def SlowComputation(): | |
502 start = time.time() | |
503 for i in range(1000): | |
504 for j in range(30000): | |
505 math.sqrt(float(j)) | |
506 end = time.time() | |
507 duration = (end - start) | |
508 return 'computation done in %.03f seconds\n' % duration | |
509 | |
510 # Ignore CTRL+C in the slave processes | |
511 def Initializer(): | |
512 signal.signal(signal.SIGINT, signal.SIG_IGN) | |
513 | |
514 # Create a pool of 4 slave Python interpreters | |
515 POOL = multiprocessing.Pool(4, initializer = Initializer) | |
516 | |
517 def OnRest(output, uri, **request): | |
518 # Offload the call to "SlowComputation" onto one slave process. | |
519 # The GIL is unlocked until the slave sends its answer back. | |
520 answer = POOL.apply(SlowComputation) | |
521 output.AnswerBuffer(answer, 'text/plain') | |
522 | |
523 orthanc.RegisterRestCallback('/computation', OnRest) | |
524 | |
525 .. highlight:: text | |
526 | |
527 Here is now the result of calling this route three times concurrently:: | |
528 | |
529 $ (curl http://localhost:8042/computation & curl http://localhost:8042/computation & curl http://localhost:8042/computation ) | |
530 computation done in 4.211 seconds | |
531 computation done in 4.215 seconds | |
532 computation done in 4.225 seconds | |
533 | |
534 As can be seen, the calls to the Python computation now fully run in | |
535 parallel (the time is cut down from 12 seconds to 4 seconds, the same | |
536 as for one isolated request). | |
537 | |
538 Note also how the ``multiprocessing`` library allows to make a fine | |
539 control over the computational resources that are available to the | |
540 Python script: The number of "slave" interpreters can be easily | |
541 changed in the constructor of the ``multiprocessing.Pool`` object, and | |
542 are fully independent of the threads used by the Orthanc server. | |
543 | |
352 | 544 .. highlight:: python |
545 | |
546 Very importantly, pay attention to the fact that only the "master" | |
547 Python interpreter has access to the Orthanc SDK. For instance, here | |
548 is how you would parse a DICOM file in a slave process:: | |
549 | |
550 import pydicom | |
551 import io | |
552 | |
553 def OffloadedDicomParsing(dicom): | |
554 # No access to the "orthanc" library here, as we are in the slave process | |
555 dataset = pydicom.dcmread(io.BytesIO(dicom)) | |
556 return str(dataset) | |
557 | |
558 def OnRest(output, uri, **request): | |
559 # The call to "orthanc.RestApiGet()" is only possible in the master process | |
560 dicom = orthanc.RestApiGet('/instances/19816330-cb02e1cf-df3a8fe8-bf510623-ccefe9f5/file') | |
561 answer = POOL.apply(OffloadedDicomParsing, args = (dicom, )) | |
562 output.AnswerBuffer(answer, 'text/plain') | |
563 | |
564 Communication primitives such as ``multiprocessing.Queue`` are | |
565 available to exchange messages from the "slave" Python interpreters to | |
566 the "master" Python interpreter if further calls to the Orthanc SDK | |
567 are required. | |
568 | |
351 | 569 Obviously, an in-depth discussion about the ``multiprocessing`` |
570 library is out of the scope of this document. There are many | |
571 references available on Internet. Also, note that ``multithreading`` | |
572 is not useful here, as Python multithreading is also limited by the | |
573 GIL, and is more targeted at dealing with costly I/O operations. |