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<h1>Source code for stem.util.conf</h1><div class="highlight"><pre>
<span class="c"># Copyright 2011-2013, Damian Johnson and The Tor Project</span>
<span class="c"># See LICENSE for licensing information</span>
<span class="sd">"""</span>
<span class="sd">Handlers for text configuration files. Configurations are simple string to</span>
<span class="sd">string mappings, with the configuration files using the following rules...</span>
<span class="sd">* the key/value is separated by a space</span>
<span class="sd">* anything after a "#" is ignored as a comment</span>
<span class="sd">* excess whitespace is trimmed</span>
<span class="sd">* empty lines are ignored</span>
<span class="sd">* multi-line values can be defined by following the key with lines starting</span>
<span class="sd"> with a '|'</span>
<span class="sd">For instance...</span>
<span class="sd">::</span>
<span class="sd"> # This is my sample config</span>
<span class="sd"> user.name Galen</span>
<span class="sd"> user.password yabba1234 # here's an inline comment</span>
<span class="sd"> user.notes takes a fancy to pepperjack cheese</span>
<span class="sd"> blankEntry.example</span>
<span class="sd"> msg.greeting</span>
<span class="sd"> |Multi-line message exclaiming of the</span>
<span class="sd"> |wonder and awe that is pepperjack!</span>
<span class="sd">... would be loaded as...</span>
<span class="sd">::</span>
<span class="sd"> config = {</span>
<span class="sd"> "user.name": "Galen",</span>
<span class="sd"> "user.password": "yabba1234",</span>
<span class="sd"> "user.notes": "takes a fancy to pepperjack cheese",</span>
<span class="sd"> "blankEntry.example": "",</span>
<span class="sd"> "msg.greeting": "Multi-line message exclaiming of the\\nwonder and awe that is pepperjack!",</span>
<span class="sd"> }</span>
<span class="sd">Configurations are managed via the :class:`~stem.util.conf.Config` class. The</span>
<span class="sd">:class:`~stem.util.conf.Config` can be be used directly with its</span>
<span class="sd">:func:`~stem.util.conf.Config.get` and :func:`~stem.util.conf.Config.set`</span>
<span class="sd">methods, but usually modules will want a local dictionary with just the</span>
<span class="sd">configurations that it cares about.</span>
<span class="sd">To do this use the :func:`~stem.util.conf.config_dict` function. For example...</span>
<span class="sd">::</span>
<span class="sd"> import getpass</span>
<span class="sd"> from stem.util import conf, connection</span>
<span class="sd"> def config_validator(key, value):</span>
<span class="sd"> if key == "timeout":</span>
<span class="sd"> # require at least a one second timeout</span>
<span class="sd"> return max(1, value)</span>
<span class="sd"> elif key == "endpoint":</span>
<span class="sd"> if not connection.is_valid_ipv4_address(value):</span>
<span class="sd"> raise ValueError("'%s' isn't a valid IPv4 address" % value)</span>
<span class="sd"> elif key == "port":</span>
<span class="sd"> if not connection.is_valid_port(value):</span>
<span class="sd"> raise ValueError("'%s' isn't a valid port" % value)</span>
<span class="sd"> elif key == "retries":</span>
<span class="sd"> # negative retries really don't make sense</span>
<span class="sd"> return max(0, value)</span>
<span class="sd"> CONFIG = conf.config_dict("ssh_login", {</span>
<span class="sd"> "username": getpass.getuser(),</span>
<span class="sd"> "password": "",</span>
<span class="sd"> "timeout": 10,</span>
<span class="sd"> "endpoint": "263.12.8.0",</span>
<span class="sd"> "port": 22,</span>
<span class="sd"> "reconnect": False,</span>
<span class="sd"> "retries": 3,</span>
<span class="sd"> }, config_validator)</span>
<span class="sd">There's several things going on here so lets take it step by step...</span>
<span class="sd">* The :func:`~stem.util.conf.config_dict` provides a dictionary that's bound</span>
<span class="sd"> to a given configuration. If the "ssh_proxy_config" configuration changes</span>
<span class="sd"> then so will the contents of CONFIG.</span>
<span class="sd">* The dictionary we're passing to :func:`~stem.util.conf.config_dict` provides</span>
<span class="sd"> two important pieces of information: default values and their types. See the</span>
<span class="sd"> Config's :func:`~stem.util.conf.Config.get` method for how these type</span>
<span class="sd"> inferences work.</span>
<span class="sd">* The config_validator is a hook we're adding to make sure CONFIG only gets</span>
<span class="sd"> values we think are valid. In this case it ensures that our timeout value</span>
<span class="sd"> is at least one second, and rejects endpoints or ports that are invalid.</span>
<span class="sd">Now lets say our user has the following configuration file...</span>
<span class="sd">::</span>
<span class="sd"> username waddle_doo</span>
<span class="sd"> password jabberwocky</span>
<span class="sd"> timeout -15</span>
<span class="sd"> port 9000000</span>
<span class="sd"> retries lots</span>
<span class="sd"> reconnect true</span>
<span class="sd"> logging debug</span>
<span class="sd">... and we load it as follows...</span>
<span class="sd">::</span>
<span class="sd"> >>> from from stem.util import conf</span>
<span class="sd"> >>> our_config = conf.get_config("ssh_login")</span>
<span class="sd"> >>> our_config.load("/home/atagar/user_config")</span>
<span class="sd"> >>> print CONFIG</span>
<span class="sd"> {</span>
<span class="sd"> "username": "waddle_doo",</span>
<span class="sd"> "password": "jabberwocky",</span>
<span class="sd"> "timeout": 1,</span>
<span class="sd"> "endpoint": "263.12.8.0",</span>
<span class="sd"> "port": 22,</span>
<span class="sd"> "reconnect": True,</span>
<span class="sd"> "retries": 3,</span>
<span class="sd"> }</span>
<span class="sd">Here's an expanation of what happened...</span>
<span class="sd">* the username, password, and reconnect attributes took the values in the</span>
<span class="sd"> configuration file</span>
<span class="sd">* the 'config_validator' we added earlier allows for a minimum timeout of one</span>
<span class="sd"> and rejected the invalid port (with a log message)</span>
<span class="sd">* we weren't able to convert the retries' "lots" value to an integer so it kept</span>
<span class="sd"> its default value and logged a warning</span>
<span class="sd">* the user didn't supply an endpoint so that remained unchanged</span>
<span class="sd">* our CONFIG didn't have a 'logging' attribute so it was ignored</span>
<span class="sd">**Module Overview:**</span>
<span class="sd">::</span>
<span class="sd"> config_dict - provides a dictionary that's kept in sync with our config</span>
<span class="sd"> get_config - singleton for getting configurations</span>
<span class="sd"> parse_enum_csv - helper funcion for parsing confguration entries for enums</span>
<span class="sd"> Config - Custom configuration</span>
<span class="sd"> |- load - reads a configuration file</span>
<span class="sd"> |- save - writes the current configuration to a file</span>
<span class="sd"> |- clear - empties our loaded configuration contents</span>
<span class="sd"> |- add_listener - notifies the given listener when an update occurs</span>
<span class="sd"> |- clear_listeners - removes any attached listeners</span>
<span class="sd"> |- keys - provides keys in the loaded configuration</span>
<span class="sd"> |- set - sets the given key/value pair</span>
<span class="sd"> |- unused_keys - provides keys that have never been requested</span>
<span class="sd"> |- get - provides the value for a given key, with type inference</span>
<span class="sd"> +- get_value - provides the value for a given key as a string</span>
<span class="sd">"""</span>
<span class="kn">import</span> <span class="nn">threading</span>
<span class="kn">from</span> <span class="nn">stem.util</span> <span class="kn">import</span> <span class="n">log</span>
<span class="n">CONFS</span> <span class="o">=</span> <span class="p">{}</span> <span class="c"># mapping of identifier to singleton instances of configs</span>
<span class="k">class</span> <span class="nc">_SyncListener</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span>
<span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">config_dict</span><span class="p">,</span> <span class="n">interceptor</span><span class="p">):</span>
<span class="bp">self</span><span class="o">.</span><span class="n">config_dict</span> <span class="o">=</span> <span class="n">config_dict</span>
<span class="bp">self</span><span class="o">.</span><span class="n">interceptor</span> <span class="o">=</span> <span class="n">interceptor</span>
<span class="k">def</span> <span class="nf">update</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">config</span><span class="p">,</span> <span class="n">key</span><span class="p">):</span>
<span class="k">if</span> <span class="n">key</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">config_dict</span><span class="p">:</span>
<span class="n">new_value</span> <span class="o">=</span> <span class="n">config</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="n">key</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">config_dict</span><span class="p">[</span><span class="n">key</span><span class="p">])</span>
<span class="k">if</span> <span class="n">new_value</span> <span class="o">==</span> <span class="bp">self</span><span class="o">.</span><span class="n">config_dict</span><span class="p">[</span><span class="n">key</span><span class="p">]:</span>
<span class="k">return</span> <span class="c"># no change</span>
<span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">interceptor</span><span class="p">:</span>
<span class="n">interceptor_value</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">interceptor</span><span class="p">(</span><span class="n">key</span><span class="p">,</span> <span class="n">new_value</span><span class="p">)</span>
<span class="k">if</span> <span class="n">interceptor_value</span><span class="p">:</span>
<span class="n">new_value</span> <span class="o">=</span> <span class="n">interceptor_value</span>
<span class="bp">self</span><span class="o">.</span><span class="n">config_dict</span><span class="p">[</span><span class="n">key</span><span class="p">]</span> <span class="o">=</span> <span class="n">new_value</span>
<div class="viewcode-block" id="config_dict"><a class="viewcode-back" href="../../../api/util/conf.html#stem.util.conf.config_dict">[docs]</a><span class="k">def</span> <span class="nf">config_dict</span><span class="p">(</span><span class="n">handle</span><span class="p">,</span> <span class="n">conf_mappings</span><span class="p">,</span> <span class="n">handler</span> <span class="o">=</span> <span class="bp">None</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> Makes a dictionary that stays synchronized with a configuration.</span>
<span class="sd"> This takes a dictionary of 'config_key => default_value' mappings and</span>
<span class="sd"> changes the values to reflect our current configuration. This will leave</span>
<span class="sd"> the previous values alone if...</span>
<span class="sd"> * we don't have a value for that config_key</span>
<span class="sd"> * we can't convert our value to be the same type as the default_value</span>
<span class="sd"> If a handler is provided then this is called just prior to assigning new</span>
<span class="sd"> values to the config_dict. The handler function is expected to accept the</span>
<span class="sd"> (key, value) for the new values and return what we should actually insert</span>
<span class="sd"> into the dictionary. If this returns None then the value is updated as</span>
<span class="sd"> normal.</span>
<span class="sd"> For more information about how we convert types see our</span>
<span class="sd"> :func:`~stem.util.conf.Config.get` method.</span>
<span class="sd"> **The dictionary you get from this is manged by the</span>
<span class="sd"> :class:`~stem.util.conf.Config` class and should be treated as being</span>
<span class="sd"> read-only.**</span>
<span class="sd"> :param str handle: unique identifier for a config instance</span>
<span class="sd"> :param dict conf_mappings: config key/value mappings used as our defaults</span>
<span class="sd"> :param functor handler: function referred to prior to assigning values</span>
<span class="sd"> """</span>
<span class="n">selected_config</span> <span class="o">=</span> <span class="n">get_config</span><span class="p">(</span><span class="n">handle</span><span class="p">)</span>
<span class="n">selected_config</span><span class="o">.</span><span class="n">add_listener</span><span class="p">(</span><span class="n">_SyncListener</span><span class="p">(</span><span class="n">conf_mappings</span><span class="p">,</span> <span class="n">handler</span><span class="p">)</span><span class="o">.</span><span class="n">update</span><span class="p">)</span>
<span class="k">return</span> <span class="n">conf_mappings</span>
</div>
<div class="viewcode-block" id="get_config"><a class="viewcode-back" href="../../../api/util/conf.html#stem.util.conf.get_config">[docs]</a><span class="k">def</span> <span class="nf">get_config</span><span class="p">(</span><span class="n">handle</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> Singleton constructor for configuration file instances. If a configuration</span>
<span class="sd"> already exists for the handle then it's returned. Otherwise a fresh instance</span>
<span class="sd"> is constructed.</span>
<span class="sd"> :param str handle: unique identifier used to access this config instance</span>
<span class="sd"> """</span>
<span class="k">if</span> <span class="ow">not</span> <span class="n">handle</span> <span class="ow">in</span> <span class="n">CONFS</span><span class="p">:</span>
<span class="n">CONFS</span><span class="p">[</span><span class="n">handle</span><span class="p">]</span> <span class="o">=</span> <span class="n">Config</span><span class="p">()</span>
<span class="k">return</span> <span class="n">CONFS</span><span class="p">[</span><span class="n">handle</span><span class="p">]</span>
</div>
<div class="viewcode-block" id="parse_enum"><a class="viewcode-back" href="../../../api/util/conf.html#stem.util.conf.parse_enum">[docs]</a><span class="k">def</span> <span class="nf">parse_enum</span><span class="p">(</span><span class="n">key</span><span class="p">,</span> <span class="n">value</span><span class="p">,</span> <span class="n">enumeration</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> Provides the enumeration value for a given key. This is a case insensitive</span>
<span class="sd"> lookup and raises an exception if the enum key doesn't exist.</span>
<span class="sd"> :param str key: configuration key being looked up</span>
<span class="sd"> :param str value: value to be parsed</span>
<span class="sd"> :param stem.util.enum.Enum enumeration: enumeration the values should be in</span>
<span class="sd"> :returns: enumeration value</span>
<span class="sd"> :raises: **ValueError** if the **value** isn't among the enumeration keys</span>
<span class="sd"> """</span>
<span class="k">return</span> <span class="n">parse_enum_csv</span><span class="p">(</span><span class="n">key</span><span class="p">,</span> <span class="n">value</span><span class="p">,</span> <span class="n">enumeration</span><span class="p">,</span> <span class="mi">1</span><span class="p">)[</span><span class="mi">0</span><span class="p">]</span>
</div>
<div class="viewcode-block" id="parse_enum_csv"><a class="viewcode-back" href="../../../api/util/conf.html#stem.util.conf.parse_enum_csv">[docs]</a><span class="k">def</span> <span class="nf">parse_enum_csv</span><span class="p">(</span><span class="n">key</span><span class="p">,</span> <span class="n">value</span><span class="p">,</span> <span class="n">enumeration</span><span class="p">,</span> <span class="n">count</span> <span class="o">=</span> <span class="bp">None</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> Parses a given value as being a comma separated listing of enumeration keys,</span>
<span class="sd"> returning the corresponding enumeration values. This is intended to be a</span>
<span class="sd"> helper for config handlers. The checks this does are case insensitive.</span>
<span class="sd"> The **count** attribute can be used to make assertions based on the number of</span>
<span class="sd"> values. This can be...</span>
<span class="sd"> * None to indicate that there's no restrictions.</span>
<span class="sd"> * An int to indicate that we should have this many values.</span>
<span class="sd"> * An (int, int) tuple to indicate the range that values can be in. This range</span>
<span class="sd"> is inclusive and either can be None to indicate the lack of a lower or</span>
<span class="sd"> upper bound.</span>
<span class="sd"> :param str key: configuration key being looked up</span>
<span class="sd"> :param str value: value to be parsed</span>
<span class="sd"> :param stem.util.enum.Enum enumeration: enumeration the values should be in</span>
<span class="sd"> :param int,tuple count: validates that we have this many items</span>
<span class="sd"> :returns: list with the enumeration values</span>
<span class="sd"> :raises: **ValueError** if the count assertion fails or the **value** entries</span>
<span class="sd"> don't match the enumeration keys</span>
<span class="sd"> """</span>
<span class="n">values</span> <span class="o">=</span> <span class="p">[</span><span class="n">val</span><span class="o">.</span><span class="n">upper</span><span class="p">()</span><span class="o">.</span><span class="n">strip</span><span class="p">()</span> <span class="k">for</span> <span class="n">val</span> <span class="ow">in</span> <span class="n">value</span><span class="o">.</span><span class="n">split</span><span class="p">(</span><span class="s">','</span><span class="p">)]</span>
<span class="k">if</span> <span class="n">values</span> <span class="o">==</span> <span class="p">[</span><span class="s">''</span><span class="p">]:</span>
<span class="k">return</span> <span class="p">[]</span>
<span class="k">if</span> <span class="n">count</span> <span class="ow">is</span> <span class="bp">None</span><span class="p">:</span>
<span class="k">pass</span> <span class="c"># no count validateion checks to do</span>
<span class="k">elif</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">count</span><span class="p">,</span> <span class="nb">int</span><span class="p">):</span>
<span class="k">if</span> <span class="nb">len</span><span class="p">(</span><span class="n">values</span><span class="p">)</span> <span class="o">!=</span> <span class="n">count</span><span class="p">:</span>
<span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s">"Config entry '</span><span class="si">%s</span><span class="s">' is expected to be </span><span class="si">%i</span><span class="s"> comma separated values, got '</span><span class="si">%s</span><span class="s">'"</span> <span class="o">%</span> <span class="p">(</span><span class="n">key</span><span class="p">,</span> <span class="n">count</span><span class="p">,</span> <span class="n">value</span><span class="p">))</span>
<span class="k">elif</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">count</span><span class="p">,</span> <span class="nb">tuple</span><span class="p">)</span> <span class="ow">and</span> <span class="nb">len</span><span class="p">(</span><span class="n">count</span><span class="p">)</span> <span class="o">==</span> <span class="mi">2</span><span class="p">:</span>
<span class="n">minimum</span><span class="p">,</span> <span class="n">maximum</span> <span class="o">=</span> <span class="n">count</span>
<span class="k">if</span> <span class="n">minimum</span> <span class="ow">is</span> <span class="ow">not</span> <span class="bp">None</span> <span class="ow">and</span> <span class="nb">len</span><span class="p">(</span><span class="n">values</span><span class="p">)</span> <span class="o"><</span> <span class="n">minimum</span><span class="p">:</span>
<span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s">"Config entry '</span><span class="si">%s</span><span class="s">' must have at least </span><span class="si">%i</span><span class="s"> comma separated values, got '</span><span class="si">%s</span><span class="s">'"</span> <span class="o">%</span> <span class="p">(</span><span class="n">key</span><span class="p">,</span> <span class="n">minimum</span><span class="p">,</span> <span class="n">value</span><span class="p">))</span>
<span class="k">if</span> <span class="n">maximum</span> <span class="ow">is</span> <span class="ow">not</span> <span class="bp">None</span> <span class="ow">and</span> <span class="nb">len</span><span class="p">(</span><span class="n">values</span><span class="p">)</span> <span class="o">></span> <span class="n">maximum</span><span class="p">:</span>
<span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s">"Config entry '</span><span class="si">%s</span><span class="s">' can have at most </span><span class="si">%i</span><span class="s"> comma separated values, got '</span><span class="si">%s</span><span class="s">'"</span> <span class="o">%</span> <span class="p">(</span><span class="n">key</span><span class="p">,</span> <span class="n">maximum</span><span class="p">,</span> <span class="n">value</span><span class="p">))</span>
<span class="k">else</span><span class="p">:</span>
<span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s">"The count must be None, an int, or two value tuple. Got '</span><span class="si">%s</span><span class="s">' (</span><span class="si">%s</span><span class="s">)'"</span> <span class="o">%</span> <span class="p">(</span><span class="n">count</span><span class="p">,</span> <span class="nb">type</span><span class="p">(</span><span class="n">count</span><span class="p">)))</span>
<span class="n">result</span> <span class="o">=</span> <span class="p">[]</span>
<span class="n">enum_keys</span> <span class="o">=</span> <span class="p">[</span><span class="n">k</span><span class="o">.</span><span class="n">upper</span><span class="p">()</span> <span class="k">for</span> <span class="n">k</span> <span class="ow">in</span> <span class="n">enumeration</span><span class="o">.</span><span class="n">keys</span><span class="p">()]</span>
<span class="n">enum_values</span> <span class="o">=</span> <span class="nb">list</span><span class="p">(</span><span class="n">enumeration</span><span class="p">)</span>
<span class="k">for</span> <span class="n">val</span> <span class="ow">in</span> <span class="n">values</span><span class="p">:</span>
<span class="k">if</span> <span class="n">val</span> <span class="ow">in</span> <span class="n">enum_keys</span><span class="p">:</span>
<span class="n">result</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">enum_values</span><span class="p">[</span><span class="n">enum_keys</span><span class="o">.</span><span class="n">index</span><span class="p">(</span><span class="n">val</span><span class="p">)])</span>
<span class="k">else</span><span class="p">:</span>
<span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s">"The '</span><span class="si">%s</span><span class="s">' entry of config entry '</span><span class="si">%s</span><span class="s">' wasn't in the enumeration (expected </span><span class="si">%s</span><span class="s">)"</span> <span class="o">%</span> <span class="p">(</span><span class="n">val</span><span class="p">,</span> <span class="n">key</span><span class="p">,</span> <span class="s">', '</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">enum_keys</span><span class="p">)))</span>
<span class="k">return</span> <span class="n">result</span>
</div>
<div class="viewcode-block" id="Config"><a class="viewcode-back" href="../../../api/util/conf.html#stem.util.conf.Config">[docs]</a><span class="k">class</span> <span class="nc">Config</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> Handler for easily working with custom configurations, providing persistence</span>
<span class="sd"> to and from files. All operations are thread safe.</span>
<span class="sd"> **Example usage:**</span>
<span class="sd"> User has a file at '/home/atagar/myConfig' with...</span>
<span class="sd"> ::</span>
<span class="sd"> destination.ip 1.2.3.4</span>
<span class="sd"> destination.port blarg</span>
<span class="sd"> startup.run export PATH=$PATH:~/bin</span>
<span class="sd"> startup.run alias l=ls</span>
<span class="sd"> And they have a script with...</span>
<span class="sd"> ::</span>
<span class="sd"> from stem.util import conf</span>
<span class="sd"> # Configuration values we'll use in this file. These are mappings of</span>
<span class="sd"> # configuration keys to the default values we'll use if the user doesn't</span>
<span class="sd"> # have something different in their config file (or it doesn't match this</span>
<span class="sd"> # type).</span>
<span class="sd"> ssh_config = conf.config_dict("ssh_login", {</span>
<span class="sd"> "login.user": "atagar",</span>
<span class="sd"> "login.password": "pepperjack_is_awesome!",</span>
<span class="sd"> "destination.ip": "127.0.0.1",</span>
<span class="sd"> "destination.port": 22,</span>
<span class="sd"> "startup.run": [],</span>
<span class="sd"> })</span>
<span class="sd"> # Makes an empty config instance with the handle of 'ssh_login'. This is</span>
<span class="sd"> # a singleton so other classes can fetch this same configuration from</span>
<span class="sd"> # this handle.</span>
<span class="sd"> user_config = conf.get_config("ssh_login")</span>
<span class="sd"> # Loads the user's configuration file, warning if this fails.</span>
<span class="sd"> try:</span>
<span class="sd"> user_config.load("/home/atagar/myConfig")</span>
<span class="sd"> except IOError as exc:</span>
<span class="sd"> print "Unable to load the user's config: %s" % exc</span>
<span class="sd"> # This replace the contents of ssh_config with the values from the user's</span>
<span class="sd"> # config file if...</span>
<span class="sd"> #</span>
<span class="sd"> # * the key is present in the config file</span>
<span class="sd"> # * we're able to convert the configuration file's value to the same type</span>
<span class="sd"> # as what's in the mapping (see the Config.get() method for how these</span>
<span class="sd"> # type inferences work)</span>
<span class="sd"> #</span>
<span class="sd"> # For instance in this case...</span>
<span class="sd"> #</span>
<span class="sd"> # * the login values are left alone because they aren't in the user's</span>
<span class="sd"> # config file</span>
<span class="sd"> #</span>
<span class="sd"> # * the 'destination.port' is also left with the value of 22 because we</span>
<span class="sd"> # can't turn "blarg" into an integer</span>
<span class="sd"> #</span>
<span class="sd"> # The other values are replaced, so ssh_config now becomes...</span>
<span class="sd"> #</span>
<span class="sd"> # {"login.user": "atagar",</span>
<span class="sd"> # "login.password": "pepperjack_is_awesome!",</span>
<span class="sd"> # "destination.ip": "1.2.3.4",</span>
<span class="sd"> # "destination.port": 22,</span>
<span class="sd"> # "startup.run": ["export PATH=$PATH:~/bin", "alias l=ls"]}</span>
<span class="sd"> #</span>
<span class="sd"> # Information for what values fail to load and why are reported to</span>
<span class="sd"> # 'stem.util.log'.</span>
<span class="sd"> """</span>
<span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="bp">self</span><span class="o">.</span><span class="n">_path</span> <span class="o">=</span> <span class="bp">None</span> <span class="c"># location we last loaded from or saved to</span>
<span class="bp">self</span><span class="o">.</span><span class="n">_contents</span> <span class="o">=</span> <span class="p">{}</span> <span class="c"># configuration key/value pairs</span>
<span class="bp">self</span><span class="o">.</span><span class="n">_listeners</span> <span class="o">=</span> <span class="p">[]</span> <span class="c"># functors to be notified of config changes</span>
<span class="c"># used for accessing _contents</span>
<span class="bp">self</span><span class="o">.</span><span class="n">_contents_lock</span> <span class="o">=</span> <span class="n">threading</span><span class="o">.</span><span class="n">RLock</span><span class="p">()</span>
<span class="c"># keys that have been requested (used to provide unused config contents)</span>
<span class="bp">self</span><span class="o">.</span><span class="n">_requested_keys</span> <span class="o">=</span> <span class="nb">set</span><span class="p">()</span>
<div class="viewcode-block" id="Config.load"><a class="viewcode-back" href="../../../api/util/conf.html#stem.util.conf.Config.load">[docs]</a> <span class="k">def</span> <span class="nf">load</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">path</span> <span class="o">=</span> <span class="bp">None</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> Reads in the contents of the given path, adding its configuration values</span>
<span class="sd"> to our current contents.</span>
<span class="sd"> :param str path: file path to be loaded, this uses the last loaded path if</span>
<span class="sd"> not provided</span>
<span class="sd"> :raises:</span>
<span class="sd"> * **IOError** if we fail to read the file (it doesn't exist, insufficient</span>
<span class="sd"> permissions, etc)</span>
<span class="sd"> * **ValueError** if no path was provided and we've never been provided one</span>
<span class="sd"> """</span>
<span class="k">if</span> <span class="n">path</span><span class="p">:</span>
<span class="bp">self</span><span class="o">.</span><span class="n">_path</span> <span class="o">=</span> <span class="n">path</span>
<span class="k">elif</span> <span class="ow">not</span> <span class="bp">self</span><span class="o">.</span><span class="n">_path</span><span class="p">:</span>
<span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s">"Unable to load configuration: no path provided"</span><span class="p">)</span>
<span class="k">with</span> <span class="nb">open</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_path</span><span class="p">,</span> <span class="s">"r"</span><span class="p">)</span> <span class="k">as</span> <span class="n">config_file</span><span class="p">:</span>
<span class="n">read_contents</span> <span class="o">=</span> <span class="n">config_file</span><span class="o">.</span><span class="n">readlines</span><span class="p">()</span>
<span class="k">with</span> <span class="bp">self</span><span class="o">.</span><span class="n">_contents_lock</span><span class="p">:</span>
<span class="k">while</span> <span class="n">read_contents</span><span class="p">:</span>
<span class="n">line</span> <span class="o">=</span> <span class="n">read_contents</span><span class="o">.</span><span class="n">pop</span><span class="p">(</span><span class="mi">0</span><span class="p">)</span>
<span class="c"># strips any commenting or excess whitespace</span>
<span class="n">comment_start</span> <span class="o">=</span> <span class="n">line</span><span class="o">.</span><span class="n">find</span><span class="p">(</span><span class="s">"#"</span><span class="p">)</span>
<span class="k">if</span> <span class="n">comment_start</span> <span class="o">!=</span> <span class="o">-</span><span class="mi">1</span><span class="p">:</span>
<span class="n">line</span> <span class="o">=</span> <span class="n">line</span><span class="p">[:</span><span class="n">comment_start</span><span class="p">]</span>
<span class="n">line</span> <span class="o">=</span> <span class="n">line</span><span class="o">.</span><span class="n">strip</span><span class="p">()</span>
<span class="c"># parse the key/value pair</span>
<span class="k">if</span> <span class="n">line</span><span class="p">:</span>
<span class="k">try</span><span class="p">:</span>
<span class="n">key</span><span class="p">,</span> <span class="n">value</span> <span class="o">=</span> <span class="n">line</span><span class="o">.</span><span class="n">split</span><span class="p">(</span><span class="s">" "</span><span class="p">,</span> <span class="mi">1</span><span class="p">)</span>
<span class="n">value</span> <span class="o">=</span> <span class="n">value</span><span class="o">.</span><span class="n">strip</span><span class="p">()</span>
<span class="k">except</span> <span class="ne">ValueError</span><span class="p">:</span>
<span class="n">log</span><span class="o">.</span><span class="n">debug</span><span class="p">(</span><span class="s">"Config entry '</span><span class="si">%s</span><span class="s">' is expected to be of the format 'Key Value', defaulting to '</span><span class="si">%s</span><span class="s">' -> ''"</span> <span class="o">%</span> <span class="p">(</span><span class="n">line</span><span class="p">,</span> <span class="n">line</span><span class="p">))</span>
<span class="n">key</span><span class="p">,</span> <span class="n">value</span> <span class="o">=</span> <span class="n">line</span><span class="p">,</span> <span class="s">""</span>
<span class="k">if</span> <span class="ow">not</span> <span class="n">value</span><span class="p">:</span>
<span class="c"># this might be a multi-line entry, try processing it as such</span>
<span class="n">multiline_buffer</span> <span class="o">=</span> <span class="p">[]</span>
<span class="k">while</span> <span class="n">read_contents</span> <span class="ow">and</span> <span class="n">read_contents</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span><span class="o">.</span><span class="n">lstrip</span><span class="p">()</span><span class="o">.</span><span class="n">startswith</span><span class="p">(</span><span class="s">"|"</span><span class="p">):</span>
<span class="n">content</span> <span class="o">=</span> <span class="n">read_contents</span><span class="o">.</span><span class="n">pop</span><span class="p">(</span><span class="mi">0</span><span class="p">)</span><span class="o">.</span><span class="n">lstrip</span><span class="p">()[</span><span class="mi">1</span><span class="p">:]</span> <span class="c"># removes '\s+|' prefix</span>
<span class="n">content</span> <span class="o">=</span> <span class="n">content</span><span class="o">.</span><span class="n">rstrip</span><span class="p">(</span><span class="s">"</span><span class="se">\n</span><span class="s">"</span><span class="p">)</span> <span class="c"># trailing newline</span>
<span class="n">multiline_buffer</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">content</span><span class="p">)</span>
<span class="k">if</span> <span class="n">multiline_buffer</span><span class="p">:</span>
<span class="bp">self</span><span class="o">.</span><span class="n">set</span><span class="p">(</span><span class="n">key</span><span class="p">,</span> <span class="s">"</span><span class="se">\n</span><span class="s">"</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">multiline_buffer</span><span class="p">),</span> <span class="bp">False</span><span class="p">)</span>
<span class="k">continue</span>
<span class="bp">self</span><span class="o">.</span><span class="n">set</span><span class="p">(</span><span class="n">key</span><span class="p">,</span> <span class="n">value</span><span class="p">,</span> <span class="bp">False</span><span class="p">)</span>
</div>
<div class="viewcode-block" id="Config.save"><a class="viewcode-back" href="../../../api/util/conf.html#stem.util.conf.Config.save">[docs]</a> <span class="k">def</span> <span class="nf">save</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">path</span> <span class="o">=</span> <span class="bp">None</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> Saves configuration contents to disk. If a path is provided then it</span>
<span class="sd"> replaces the configuration location that we track.</span>
<span class="sd"> :param str path: location to be saved to</span>
<span class="sd"> :raises: **ValueError** if no path was provided and we've never been provided one</span>
<span class="sd"> """</span>
<span class="k">if</span> <span class="n">path</span><span class="p">:</span>
<span class="bp">self</span><span class="o">.</span><span class="n">_path</span> <span class="o">=</span> <span class="n">path</span>
<span class="k">elif</span> <span class="ow">not</span> <span class="bp">self</span><span class="o">.</span><span class="n">_path</span><span class="p">:</span>
<span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s">"Unable to save configuration: no path provided"</span><span class="p">)</span>
<span class="k">with</span> <span class="bp">self</span><span class="o">.</span><span class="n">_contents_lock</span><span class="p">:</span>
<span class="k">with</span> <span class="nb">open</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_path</span><span class="p">,</span> <span class="s">'w'</span><span class="p">)</span> <span class="k">as</span> <span class="n">output_file</span><span class="p">:</span>
<span class="k">for</span> <span class="n">entry_key</span> <span class="ow">in</span> <span class="nb">sorted</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">keys</span><span class="p">()):</span>
<span class="k">for</span> <span class="n">entry_value</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">get_value</span><span class="p">(</span><span class="n">entry_key</span><span class="p">,</span> <span class="n">multiple</span> <span class="o">=</span> <span class="bp">True</span><span class="p">):</span>
<span class="c"># check for multi line entries</span>
<span class="k">if</span> <span class="s">"</span><span class="se">\n</span><span class="s">"</span> <span class="ow">in</span> <span class="n">entry_value</span><span class="p">:</span>
<span class="n">entry_value</span> <span class="o">=</span> <span class="s">"</span><span class="se">\n</span><span class="s">|"</span> <span class="o">+</span> <span class="n">entry_value</span><span class="o">.</span><span class="n">replace</span><span class="p">(</span><span class="s">"</span><span class="se">\n</span><span class="s">"</span><span class="p">,</span> <span class="s">"</span><span class="se">\n</span><span class="s">|"</span><span class="p">)</span>
<span class="n">output_file</span><span class="o">.</span><span class="n">write</span><span class="p">(</span><span class="s">'</span><span class="si">%s</span><span class="s"> </span><span class="si">%s</span><span class="se">\n</span><span class="s">'</span> <span class="o">%</span> <span class="p">(</span><span class="n">entry_key</span><span class="p">,</span> <span class="n">entry_value</span><span class="p">))</span>
</div>
<div class="viewcode-block" id="Config.clear"><a class="viewcode-back" href="../../../api/util/conf.html#stem.util.conf.Config.clear">[docs]</a> <span class="k">def</span> <span class="nf">clear</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> Drops the configuration contents and reverts back to a blank, unloaded</span>
<span class="sd"> state.</span>
<span class="sd"> """</span>
<span class="k">with</span> <span class="bp">self</span><span class="o">.</span><span class="n">_contents_lock</span><span class="p">:</span>
<span class="bp">self</span><span class="o">.</span><span class="n">_contents</span><span class="o">.</span><span class="n">clear</span><span class="p">()</span>
<span class="bp">self</span><span class="o">.</span><span class="n">_requested_keys</span> <span class="o">=</span> <span class="nb">set</span><span class="p">()</span>
</div>
<div class="viewcode-block" id="Config.add_listener"><a class="viewcode-back" href="../../../api/util/conf.html#stem.util.conf.Config.add_listener">[docs]</a> <span class="k">def</span> <span class="nf">add_listener</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">listener</span><span class="p">,</span> <span class="n">backfill</span> <span class="o">=</span> <span class="bp">True</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> Registers the function to be notified of configuration updates. Listeners</span>
<span class="sd"> are expected to be functors which accept (config, key).</span>
<span class="sd"> :param functor listener: function to be notified when our configuration is changed</span>
<span class="sd"> :param bool backfill: calls the function with our current values if **True**</span>
<span class="sd"> """</span>
<span class="k">with</span> <span class="bp">self</span><span class="o">.</span><span class="n">_contents_lock</span><span class="p">:</span>
<span class="bp">self</span><span class="o">.</span><span class="n">_listeners</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">listener</span><span class="p">)</span>
<span class="k">if</span> <span class="n">backfill</span><span class="p">:</span>
<span class="k">for</span> <span class="n">key</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">keys</span><span class="p">():</span>
<span class="n">listener</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">key</span><span class="p">)</span>
</div>
<div class="viewcode-block" id="Config.clear_listeners"><a class="viewcode-back" href="../../../api/util/conf.html#stem.util.conf.Config.clear_listeners">[docs]</a> <span class="k">def</span> <span class="nf">clear_listeners</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> Removes all attached listeners.</span>
<span class="sd"> """</span>
<span class="bp">self</span><span class="o">.</span><span class="n">_listeners</span> <span class="o">=</span> <span class="p">[]</span>
</div>
<div class="viewcode-block" id="Config.keys"><a class="viewcode-back" href="../../../api/util/conf.html#stem.util.conf.Config.keys">[docs]</a> <span class="k">def</span> <span class="nf">keys</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> Provides all keys in the currently loaded configuration.</span>
<span class="sd"> :returns: **list** if strings for the configuration keys we've loaded</span>
<span class="sd"> """</span>
<span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_contents</span><span class="o">.</span><span class="n">keys</span><span class="p">()</span>
</div>
<div class="viewcode-block" id="Config.unused_keys"><a class="viewcode-back" href="../../../api/util/conf.html#stem.util.conf.Config.unused_keys">[docs]</a> <span class="k">def</span> <span class="nf">unused_keys</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> Provides the configuration keys that have never been provided to a caller</span>
<span class="sd"> via :func:`~stem.util.conf.config_dict` or the</span>
<span class="sd"> :func:`~stem.util.conf.Config.get` and</span>
<span class="sd"> :func:`~stem.util.conf.Config.get_value` methods.</span>
<span class="sd"> :returns: **set** of configuration keys we've loaded but have never been requested</span>
<span class="sd"> """</span>
<span class="k">return</span> <span class="nb">set</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">keys</span><span class="p">())</span><span class="o">.</span><span class="n">difference</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_requested_keys</span><span class="p">)</span>
</div>
<div class="viewcode-block" id="Config.set"><a class="viewcode-back" href="../../../api/util/conf.html#stem.util.conf.Config.set">[docs]</a> <span class="k">def</span> <span class="nf">set</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">key</span><span class="p">,</span> <span class="n">value</span><span class="p">,</span> <span class="n">overwrite</span> <span class="o">=</span> <span class="bp">True</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> Appends the given key/value configuration mapping, behaving the same as if</span>
<span class="sd"> we'd loaded this from a configuration file.</span>
<span class="sd"> :param str key: key for the configuration mapping</span>
<span class="sd"> :param str,list value: value we're setting the mapping to</span>
<span class="sd"> :param bool overwrite: replaces the previous value if **True**, otherwise</span>
<span class="sd"> the values are appended</span>
<span class="sd"> """</span>
<span class="k">with</span> <span class="bp">self</span><span class="o">.</span><span class="n">_contents_lock</span><span class="p">:</span>
<span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">value</span><span class="p">,</span> <span class="nb">str</span><span class="p">):</span>
<span class="k">if</span> <span class="ow">not</span> <span class="n">overwrite</span> <span class="ow">and</span> <span class="n">key</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_contents</span><span class="p">:</span>
<span class="bp">self</span><span class="o">.</span><span class="n">_contents</span><span class="p">[</span><span class="n">key</span><span class="p">]</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">value</span><span class="p">)</span>
<span class="k">else</span><span class="p">:</span>
<span class="bp">self</span><span class="o">.</span><span class="n">_contents</span><span class="p">[</span><span class="n">key</span><span class="p">]</span> <span class="o">=</span> <span class="p">[</span><span class="n">value</span><span class="p">]</span>
<span class="k">for</span> <span class="n">listener</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_listeners</span><span class="p">:</span>
<span class="n">listener</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">key</span><span class="p">)</span>
<span class="k">elif</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">value</span><span class="p">,</span> <span class="p">(</span><span class="nb">list</span><span class="p">,</span> <span class="nb">tuple</span><span class="p">)):</span>
<span class="k">if</span> <span class="ow">not</span> <span class="n">overwrite</span> <span class="ow">and</span> <span class="n">key</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_contents</span><span class="p">:</span>
<span class="bp">self</span><span class="o">.</span><span class="n">_contents</span><span class="p">[</span><span class="n">key</span><span class="p">]</span> <span class="o">+=</span> <span class="n">value</span>
<span class="k">else</span><span class="p">:</span>
<span class="bp">self</span><span class="o">.</span><span class="n">_contents</span><span class="p">[</span><span class="n">key</span><span class="p">]</span> <span class="o">=</span> <span class="n">value</span>
<span class="k">for</span> <span class="n">listener</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_listeners</span><span class="p">:</span>
<span class="n">listener</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">key</span><span class="p">)</span>
<span class="k">else</span><span class="p">:</span>
<span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s">"Config.set() only accepts str, list, or tuple. Provided value was a '</span><span class="si">%s</span><span class="s">'"</span> <span class="o">%</span> <span class="nb">type</span><span class="p">(</span><span class="n">value</span><span class="p">))</span>
</div>
<div class="viewcode-block" id="Config.get"><a class="viewcode-back" href="../../../api/util/conf.html#stem.util.conf.Config.get">[docs]</a> <span class="k">def</span> <span class="nf">get</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">key</span><span class="p">,</span> <span class="n">default</span> <span class="o">=</span> <span class="bp">None</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> Fetches the given configuration, using the key and default value to</span>
<span class="sd"> determine the type it should be. Recognized inferences are:</span>
<span class="sd"> * **default is a boolean => boolean**</span>
<span class="sd"> * values are case insensitive</span>
<span class="sd"> * provides the default if the value isn't "true" or "false"</span>
<span class="sd"> * **default is an integer => int**</span>
<span class="sd"> * provides the default if the value can't be converted to an int</span>
<span class="sd"> * **default is a float => float**</span>
<span class="sd"> * provides the default if the value can't be converted to a float</span>
<span class="sd"> * **default is a list => list**</span>
<span class="sd"> * string contents for all configuration values with this key</span>
<span class="sd"> * **default is a tuple => tuple**</span>
<span class="sd"> * string contents for all configuration values with this key</span>
<span class="sd"> * **default is a dictionary => dict**</span>
<span class="sd"> * values without "=>" in them are ignored</span>
<span class="sd"> * values are split into key/value pairs on "=>" with extra whitespace</span>
<span class="sd"> stripped</span>
<span class="sd"> :param str key: config setting to be fetched</span>
<span class="sd"> :param default object: value provided if no such key exists or fails to be converted</span>
<span class="sd"> :returns: given configuration value with its type inferred with the above rules</span>
<span class="sd"> """</span>
<span class="n">is_multivalue</span> <span class="o">=</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">default</span><span class="p">,</span> <span class="p">(</span><span class="nb">list</span><span class="p">,</span> <span class="nb">tuple</span><span class="p">,</span> <span class="nb">dict</span><span class="p">))</span>
<span class="n">val</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">get_value</span><span class="p">(</span><span class="n">key</span><span class="p">,</span> <span class="n">default</span><span class="p">,</span> <span class="n">is_multivalue</span><span class="p">)</span>
<span class="k">if</span> <span class="n">val</span> <span class="o">==</span> <span class="n">default</span><span class="p">:</span>
<span class="k">return</span> <span class="n">val</span> <span class="c"># don't try to infer undefined values</span>
<span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">default</span><span class="p">,</span> <span class="nb">bool</span><span class="p">):</span>
<span class="k">if</span> <span class="n">val</span><span class="o">.</span><span class="n">lower</span><span class="p">()</span> <span class="o">==</span> <span class="s">"true"</span><span class="p">:</span>
<span class="n">val</span> <span class="o">=</span> <span class="bp">True</span>
<span class="k">elif</span> <span class="n">val</span><span class="o">.</span><span class="n">lower</span><span class="p">()</span> <span class="o">==</span> <span class="s">"false"</span><span class="p">:</span>
<span class="n">val</span> <span class="o">=</span> <span class="bp">False</span>
<span class="k">else</span><span class="p">:</span>
<span class="n">log</span><span class="o">.</span><span class="n">debug</span><span class="p">(</span><span class="s">"Config entry '</span><span class="si">%s</span><span class="s">' is expected to be a boolean, defaulting to '</span><span class="si">%s</span><span class="s">'"</span> <span class="o">%</span> <span class="p">(</span><span class="n">key</span><span class="p">,</span> <span class="nb">str</span><span class="p">(</span><span class="n">default</span><span class="p">)))</span>
<span class="n">val</span> <span class="o">=</span> <span class="n">default</span>
<span class="k">elif</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">default</span><span class="p">,</span> <span class="nb">int</span><span class="p">):</span>
<span class="k">try</span><span class="p">:</span>
<span class="n">val</span> <span class="o">=</span> <span class="nb">int</span><span class="p">(</span><span class="n">val</span><span class="p">)</span>
<span class="k">except</span> <span class="ne">ValueError</span><span class="p">:</span>
<span class="n">log</span><span class="o">.</span><span class="n">debug</span><span class="p">(</span><span class="s">"Config entry '</span><span class="si">%s</span><span class="s">' is expected to be an integer, defaulting to '</span><span class="si">%i</span><span class="s">'"</span> <span class="o">%</span> <span class="p">(</span><span class="n">key</span><span class="p">,</span> <span class="n">default</span><span class="p">))</span>
<span class="n">val</span> <span class="o">=</span> <span class="n">default</span>
<span class="k">elif</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">default</span><span class="p">,</span> <span class="nb">float</span><span class="p">):</span>
<span class="k">try</span><span class="p">:</span>
<span class="n">val</span> <span class="o">=</span> <span class="nb">float</span><span class="p">(</span><span class="n">val</span><span class="p">)</span>
<span class="k">except</span> <span class="ne">ValueError</span><span class="p">:</span>
<span class="n">log</span><span class="o">.</span><span class="n">debug</span><span class="p">(</span><span class="s">"Config entry '</span><span class="si">%s</span><span class="s">' is expected to be a float, defaulting to '</span><span class="si">%f</span><span class="s">'"</span> <span class="o">%</span> <span class="p">(</span><span class="n">key</span><span class="p">,</span> <span class="n">default</span><span class="p">))</span>
<span class="n">val</span> <span class="o">=</span> <span class="n">default</span>
<span class="k">elif</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">default</span><span class="p">,</span> <span class="nb">list</span><span class="p">):</span>
<span class="k">pass</span> <span class="c"># nothing special to do (already a list)</span>
<span class="k">elif</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">default</span><span class="p">,</span> <span class="nb">tuple</span><span class="p">):</span>
<span class="n">val</span> <span class="o">=</span> <span class="nb">tuple</span><span class="p">(</span><span class="n">val</span><span class="p">)</span>
<span class="k">elif</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">default</span><span class="p">,</span> <span class="nb">dict</span><span class="p">):</span>
<span class="n">valMap</span> <span class="o">=</span> <span class="p">{}</span>
<span class="k">for</span> <span class="n">entry</span> <span class="ow">in</span> <span class="n">val</span><span class="p">:</span>
<span class="k">if</span> <span class="s">"=>"</span> <span class="ow">in</span> <span class="n">entry</span><span class="p">:</span>
<span class="n">entryKey</span><span class="p">,</span> <span class="n">entryVal</span> <span class="o">=</span> <span class="n">entry</span><span class="o">.</span><span class="n">split</span><span class="p">(</span><span class="s">"=>"</span><span class="p">,</span> <span class="mi">1</span><span class="p">)</span>
<span class="n">valMap</span><span class="p">[</span><span class="n">entryKey</span><span class="o">.</span><span class="n">strip</span><span class="p">()]</span> <span class="o">=</span> <span class="n">entryVal</span><span class="o">.</span><span class="n">strip</span><span class="p">()</span>
<span class="k">else</span><span class="p">:</span>
<span class="n">log</span><span class="o">.</span><span class="n">debug</span><span class="p">(</span><span class="s">"Ignoring invalid </span><span class="si">%s</span><span class="s"> config entry (expected a mapping, but </span><span class="se">\"</span><span class="si">%s</span><span class="se">\"</span><span class="s"> was missing </span><span class="se">\"</span><span class="s">=></span><span class="se">\"</span><span class="s">)"</span> <span class="o">%</span> <span class="p">(</span><span class="n">key</span><span class="p">,</span> <span class="n">entry</span><span class="p">))</span>
<span class="n">val</span> <span class="o">=</span> <span class="n">valMap</span>
<span class="k">return</span> <span class="n">val</span>
</div>
<div class="viewcode-block" id="Config.get_value"><a class="viewcode-back" href="../../../api/util/conf.html#stem.util.conf.Config.get_value">[docs]</a> <span class="k">def</span> <span class="nf">get_value</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">key</span><span class="p">,</span> <span class="n">default</span> <span class="o">=</span> <span class="bp">None</span><span class="p">,</span> <span class="n">multiple</span> <span class="o">=</span> <span class="bp">False</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> This provides the current value associated with a given key.</span>
<span class="sd"> :param str key: config setting to be fetched</span>
<span class="sd"> :param object default: value provided if no such key exists</span>
<span class="sd"> :param bool multiple: provides back a list of all values if **True**,</span>
<span class="sd"> otherwise this returns the last loaded configuration value</span>
<span class="sd"> :returns: **str** or **list** of string configuration values associated</span>
<span class="sd"> with the given key, providing the default if no such key exists</span>
<span class="sd"> """</span>
<span class="k">with</span> <span class="bp">self</span><span class="o">.</span><span class="n">_contents_lock</span><span class="p">:</span>
<span class="k">if</span> <span class="n">key</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_contents</span><span class="p">:</span>
<span class="bp">self</span><span class="o">.</span><span class="n">_requested_keys</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">key</span><span class="p">)</span>
<span class="k">if</span> <span class="n">multiple</span><span class="p">:</span>
<span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_contents</span><span class="p">[</span><span class="n">key</span><span class="p">]</span>
<span class="k">else</span><span class="p">:</span>
<span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_contents</span><span class="p">[</span><span class="n">key</span><span class="p">][</span><span class="o">-</span><span class="mi">1</span><span class="p">]</span>
<span class="k">else</span><span class="p">:</span>
<span class="n">message_id</span> <span class="o">=</span> <span class="s">"stem.util.conf.missing_config_key_</span><span class="si">%s</span><span class="s">"</span> <span class="o">%</span> <span class="n">key</span>
<span class="n">log</span><span class="o">.</span><span class="n">log_once</span><span class="p">(</span><span class="n">message_id</span><span class="p">,</span> <span class="n">log</span><span class="o">.</span><span class="n">TRACE</span><span class="p">,</span> <span class="s">"config entry '</span><span class="si">%s</span><span class="s">' not found, defaulting to '</span><span class="si">%s</span><span class="s">'"</span> <span class="o">%</span> <span class="p">(</span><span class="n">key</span><span class="p">,</span> <span class="n">default</span><span class="p">))</span>
<span class="k">return</span> <span class="n">default</span></div></div>
</pre></div>
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