XML Example

Here is an example of an XML continuous query definition. SAS Micro Analytic Service related elements are highlighted.
<engine port='55555'>
  <description>
    This example has one source window and one procedural
    window. The procedural window uses DS2 code to calculate
    a value from the source window.

    The engine element creates the single engine top level container which
    sets up dfESP fundamental services such as licensing and logging.
    This single engine instance wraps one or more projects that wrap
    one or more continuous queries and different types of windows.
  </description>
  <projects>
    <project name='trades_proj' pubsub='auto' threads='4'>
      <description>
        This is to create a project. A project specifies a container
        that holds one or more continuous queries and are backed by a
        thread pool of user defined size. You can specify the pubsub
        port and type, number of threads for the project, index type, 
        and a tag token data flow model.
      </description>
        <mas-modules>
          <mas-module language="ds2" module="module_1" func-names='compute_volume'>
            <description>
              <![CDATA[This is a SAS Micro Analytic Service module in DS2 ]]>
            </description>
            <code>
              <![CDATA[
              ds2_options sas;  /* SAS-style missing value handling */
              package module_1/overwrite=yes;
                method compute_volume(int quantity, double price, in_out int volume);
                  volume = quantity * price;
                end;
              endpackage;
              ]]>
            </code>
            </mas-module>
          </mas-modules>
      <contqueries>
        <contquery name='trades_traders_cq' trace='pw1'>
          <description>
            This specifies the continuous query container that holds
            a collection of windows and enables you to specify the
            connectivity between windows. You can turn on tracing
            for a list of windows, and specify the index type for
            windows in the query.
          </description>
          <windows>
            <window-source name='Trades' index='pi_RBTREE'>
              <description>
                This defines a source window. All event streams must
                enter continuous queries by being published or
                injected into a source window.
              </description>
              <schema>
                <fields>
                  <field name='tradeID' type='string' key='true'/>
                  <field name='security' type='string'/>
                  <field name='quantity' type='int32'/>
                  <field name='price' type='double'/>
                  <field name='traderID' type='int64'/>
                  <field name='time' type='string'/>
                </fields>
              </schema>
              <connectors>
                <connector class='fs' name='pub'>
                  <properties>
                    <property name='type'>pub</property>
                    <property name='fstype'>csv</property>
                    <property name='fsname'>input.csv</property>
                    <property name='transactional'>true</property>
                  </properties>
                </connector>
              </connectors>
            </window-source>
            <window-procedural name='pw1'>
              <description>
                This defines a procedural window. The window passes
                all fields of the event as variables to the DS2 program.
              </description>
              <schema>
                <fields>
                  <field name='tradeID' type='string' key='true'/>
                  <field name='security' type='string'/>
                  <field name='quantity' type='int32'/>
                  <field name='price' type='double'/>
                  <field name='traderID' type='int64'/>
                  <field name='time' type='string'/>
                  <field name='volume' type='int32' key='true'/>
                </fields>
              </schema>
              <mas-map>
                <window-map module="module_1" revision="0" source="Trades"
                   function="compute_volume"/>
              </mas-map>
              <connectors>
                <connector class='fs' name='sub'>
                  <properties>
                    <property name='type'>sub</property>
                    <property name='fstype'>csv</property>
                    <property name='fsname'>output.csv</property>
                    <property name='snapshot'>true</property>
                  </properties>
                </connector>
              </connectors>
            </window-procedural>
          </windows>
          <edges>
            <description>
              This fully specifies the continuous query with window
              connectivity, which is a directed graph.
            </description>
            <edge source='Trades' target='pw1'/>
          </edges>
        </contquery>
      </contqueries>
      <project-connectors>
        <connector-groups>
          <connector-group name='sub_group'>
            <connector-entry connector='trades_traders_cq/pw1/sub'
                state='running'/>
          </connector-group>
          <connector-group name='pub_group'>
            <connector-entry connector='trades_traders_cq/Trades/pub'
               state='finished'/>
          </connector-group>
        </connector-groups>
        <edges>
          <edge source='sub_group' target='pub_group'/>
        </edges>
      </project-connectors>
    </project>
  </projects>
</engine>
Last updated: March 2, 2017