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1 #!/usr/bin/python2.5 |
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2 # |
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3 # Copyright 2008 the Melange authors. |
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4 # |
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5 # Licensed under the Apache License, Version 2.0 (the "License"); |
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6 # you may not use this file except in compliance with the License. |
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7 # You may obtain a copy of the License at |
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8 # |
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9 # http://www.apache.org/licenses/LICENSE-2.0 |
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10 # |
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11 # Unless required by applicable law or agreed to in writing, software |
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12 # distributed under the License is distributed on an "AS IS" BASIS, |
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13 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
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14 # See the License for the specific language governing permissions and |
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15 # limitations under the License. |
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16 |
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17 """Helpers functions for updating different kinds of models in datastore. |
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18 """ |
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19 |
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20 __authors__ = [ |
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21 '"Pawel Solyga" <pawel.solyga@gmail.com>', |
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22 ] |
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23 |
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24 from google.appengine.ext import db |
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25 |
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26 def updateModelProperties(model, **model_properties): |
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27 """Update existing model entity using supplied model properties. |
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28 |
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29 Args: |
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30 model: a model entity |
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31 **model_properties: keyword arguments that correspond to model entity |
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32 properties and their values |
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33 |
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34 Returns: |
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35 the original model entity with any supplied properties changed |
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36 """ |
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37 def update(): |
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38 return _unsafeUpdateModelProperties(model, **model_properties) |
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39 |
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40 return db.run_in_transaction(update) |
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41 |
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42 |
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43 def _unsafeUpdateModelProperties(model, **model_properties): |
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44 """(see updateModelProperties) |
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45 |
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46 Like updateModelProperties(), but not run within a transaction. |
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47 """ |
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48 properties = model.properties() |
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49 |
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50 for prop in properties.values(): |
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51 if prop.name in model_properties: |
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52 value = model_properties[prop.name] |
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53 prop.__set__(model, value) |
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54 |
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55 model.put() |
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56 return model |