DynamicChoiceStringParameter: a base class for dynamic lists in Force…

…Scheduler

Provide a better mechanism for generating dynamic content for ForceScheduler, and
adjust the InheritBuildParameter to use this new base class.

master/buildbot/schedulers/forcesched.py

@@ -210,13 +210,40 @@ def parse_from_arg(self, s):
         return s
 
 
+class DynamicChoiceStringParameter(ChoiceStringParameter):
+    """A list of strings, allowing the selection of one of the predefined values.
+       The 'strict' parameter controls whether values outside the predefined list
+       of choices are allowed"""
+    type = ChoiceStringParameter.type + ["dynamic"]
+
+    # Assume not strict. In general, there is no "session" to remember what each
+    # user was presented with, so there is no way to validate a user's selection.
+    # Custom validation can be implemented in a derived 'updateFromKwargs', if desired.
+    strict = False 
 
-class InheritBuildParameter(ChoiceStringParameter):
+    # A functor to return the choices available. This will be called for each
+    # form generation, and the first element will be presented as the default
+    # choice. 
+    dynamicChoices = lambda masterStatus, buildername: []
+
+
+class InheritBuildParameter(DynamicChoiceStringParameter):
     """A parameter that takes its values from another build"""
-    type = ChoiceStringParameter.type + ["inherit"]
+    type = DynamicChoiceStringParameter.type + ["inherit"]
     name = "inherit"
     compatible_builds = None
+    strict = True
 
+    def __init__(self, compatible_builds=None, **kw):
+        def dynamicChoices(masterStatus, buildername):
+            # cache the choices because that's what we've always done
+            self.choices = self.compatible_builds(masterStatus, buildername)
+            return self.choices
+
+        DynamicChoiceStringParameter.__init__(self,
+                                              compatible_builds=compatible_builds,
+                                              dynamicChoices=dynamicChoices,
+                                              **kw)
     def getFromKwargs(self, kwargs):
         raise ValidationError("InheritBuildParameter can only be used by properties")
 

master/buildbot/status/web/builder.py

@@ -25,7 +25,6 @@
     map_branches, path_to_authzfail, ActionResource, \
     getRequestCharset
 from buildbot.schedulers.forcesched import ForceScheduler
-from buildbot.schedulers.forcesched import InheritBuildParameter, NestedParameter
 from buildbot.schedulers.forcesched import ValidationError
 from buildbot.status.web.build import BuildsResource, StatusResourceBuild
 from buildbot import util
@@ -177,23 +176,23 @@ def buildForceContextForField(req, default_props, sch, field, master, buildernam
     pname = "%s.%s"%(sch.name, field.fullName)
 
     default = field.default
-    if isinstance(field, InheritBuildParameter):
-        # yes, I know, its bad to overwrite the parameter attribute,
-        # but I dont have any other simple way of doing this atm.
-        field.choices = field.compatible_builds(master.status, buildername)
-        if field.choices:
-            default = field.choices[0]
+
+    if "dynamic" in field.type:
+        choices = field.dynamicChoices(master.status, buildername)
+        default_props[pname+".choices"] = choices
+        if choices:
+            default = choices[0]
 
     default = req.args.get(pname, [default])[0]
     if "bool" in field.type:
-        default_props[pname] = "checked" if default else ""
-    else:
+        default = "checked" if default else ""
+    elif isinstance(default, unicode):
         # filter out unicode chars, and html stuff
-        if isinstance(default, unicode):
-            default = html.escape(default.encode('utf-8','ignore'))
-        default_props[pname] = default
+        default = html.escape(default.encode('utf-8','ignore'))
+
+    default_props[pname] = default
 
-    if isinstance(field, NestedParameter):
+    if "nested" in field.type:
         for subfield in field.fields:
             buildForceContextForField(req, default_props, sch, subfield, master, buildername)
 

master/buildbot/status/web/templates/forms.html

@@ -94,7 +94,8 @@
        <span class="label">{{f.label}}</span>
        <span class="select">
        <select name='{{f.fullName}}' {{ f.multiple and "multiple" or ""}}>
-         {% for c in f.choices %}
+         {% set choices = f.choices if 'dynamic' not in f.type else default_props[sch.name+"."+f.fullName+".choices"] %}
+         {% for c in choices %}
          <option {{(c in default_props[sch.name+"."+f.fullName]) and "selected" or ""}}>{{c}}</option>
          {% endfor %}
        </select>

master/buildbot/test/unit/test_schedulers_forcesched.py

@@ -22,6 +22,7 @@
 from buildbot.schedulers.forcesched import ChoiceStringParameter, ValidationError
 from buildbot.schedulers.forcesched import NestedParameter, AnyPropertyParameter
 from buildbot.schedulers.forcesched import CodebaseParameter, BaseParameter
+from buildbot.schedulers.forcesched import DynamicChoiceStringParameter
 from buildbot.test.util import scheduler
 from buildbot.test.util.config import ConfigErrorsMixin
 
@@ -379,6 +380,11 @@ def test_ChoiceParameterError(self):
                 klass=ChoiceStringParameter, choices=['t1','t2'],
                 debug=False)
 
+    def test_ChoiceParameterError_notStrict(self):
+        self.do_ParameterTest(value='t1', expect='t1',
+                strict=False,
+                klass=ChoiceStringParameter, choices=['t1','t2'])
+
 
     def test_ChoiceParameterMultiple(self):
         self.do_ParameterTest(value=['t1','t2'], expect=['t1','t2'],
@@ -393,6 +399,26 @@ def test_ChoiceParameterMultipleError(self):
                 multiple=True, debug=False)
 
 
+    def test_DynamicChoiceStringParameter(self):
+        self.do_ParameterTest(value='t1', expect='t1',
+                klass=DynamicChoiceStringParameter, dynamicChoices=lambda m,b: ['t1','t2'])
+
+    def test_DynamicChoiceStringParameter_notStrict(self):
+        # the 'dynamicChoices' parameter really doesnt get called, so it really doesnt apply here
+        self.do_ParameterTest(value='t3', expect='t3',
+                strict=False,
+                klass=DynamicChoiceStringParameter, dynamicChoices=lambda m,b: ['t1','t2'])
+
+    def test_DynamicChoiceStringParameter_strict(self):
+        # the 'dynamicChoices' value doesnt affect the validation, so even a "GOOD" value will
+        # fail for strict=True tests, unless programmer overrides and provides their own validation
+        self.do_ParameterTest(value='t1',
+                strict=True,
+                expect=ValidationError,
+                expectKind=Exception,
+                klass=DynamicChoiceStringParameter, dynamicChoices=lambda m,b: ['t1','t2'],
+                debug=False)
+
     def test_NestedParameter(self):
         fields = [
             IntParameter(name="foo")

master/docs/manual/cfg-schedulers.rst

@@ -1121,6 +1121,10 @@ Example::
 CodebaseParameter
 #####################
 
+::
+
+    CodebaseParameter(codebase="mycode")
+
 This is a parameter group to specify a sourcestamp for a given codebase.
 
 ``codebase``
@@ -1147,6 +1151,36 @@ This is a parameter group to specify a sourcestamp for a given codebase.
     A :ref:`parameter <ForceScheduler-Parameters>` specifying the project for
     the build.  The default value is a string parameter.
 
+
+.. bb:sched:: DynamicChoiceStringParameter
+
+DynamicChoiceStringParameter
+############################
+
+::
+
+    DynamicChoiceStringParameter(name="param",
+        dynamicChoices=functor)
+
+This is a special parameter base class for generating dynamic content. It shares
+the same fields as :py:class:`~ChoiceStringParameter`, but the choices will be
+generated by a call to ``dynamicChoices``.
+
+By default, this class works with ``strict=False``, and the selection will NOT be 
+validated. Since there is no method for tracking a user "session", it is not possible
+to store the values displayed for a particular user and validate their selection against
+"their" values. For a reference of ways to implement custom validation, please refer
+to the source for the :py:class:`~InheritBuildParameter` subclass.
+
+``dynamicChoices``
+
+   A function to generate the choices to be presented.  This function is
+   given the master :py:class:`~buildbot.status.master.Status` instance as
+   first argument, and the current builder name as second argument. It should
+   return a list of values, from which the first element in the list will be 
+   selected by default.
+
+
 InheritBuildParameter
 #####################
 

master/docs/relnotes/index.rst

@@ -27,6 +27,8 @@ Features
 
 * :bb:step:`CopyDirectory` has been added.
 
+* :bb:sched:`DynamicChoiceStringParameter` has been added.
+
 * default.css now wraps preformatted text by default.
 
 * Slaves can now be paused through the web status.