model.xml

<project name="lua_module" threads="1" pubsub="auto" heartbeat-interval="1" luaroot="@ESP_PROJECT_OUTPUT@/luaroot">
  <description><![CDATA[This example demonstrates how you can define useful functions in a Lua module at project level and reference those functions from other Lua code in the project.]]></description>
  <metadata>
    <meta id="layout">{"cq1":{"Lua":{"x":50,"y":175},"Source":{"x":50,"y":50}}}</meta>
    <meta id="studioUploadedBy">anonymousUser</meta>
    <meta id="studioUploaded">1722341337292</meta>
    <meta id="studioModifiedBy">anonymousUser</meta>
    <meta id="studioModified">1722341353358</meta>
    <meta id="studioTags">Example</meta>
  </metadata>
  <lua-modules>
    <lua-module name="logger">
      <description><![CDATA[This Lua module defines logging functions.]]></description>
      <code><![CDATA[Logger = {
            _context = nil
        }

        function Logger:new(context)
            o = {}
            setmetatable(o,self)
            self.__index = self
            self._context = context or "mylogger"
            return o
        end

        function Logger:error(msg,line)
            esp_logMessage(self._context,msg,"error",line)
        end

        function Logger:warn(msg,line)
            esp_logMessage(self._context,msg,"warn",line)
        end

        function Logger:fatal(msg,line)
            esp_logMessage(self._context,msg,"fatal",line)
        end

        function Logger:info(msg,line)
            esp_logMessage(self._context,msg,"info",line)
        end

        function Logger:debug(msg,line)
            esp_logMessage(self._context,msg,"debug",line)
        end

        function Logger:trace(msg,line)
            esp_logMessage(self._context,msg,"trace",line)
        end]]></code>
    </lua-module>
  </lua-modules>
  <contqueries>
    <contquery name="cq1">
      <windows>
        <window-source name="Source">
          <description><![CDATA[The Source window streams information from the lua_module.csv file to the Lua window.]]></description>
          <schema>
            <fields>
              <field name="id" type="string" key="true"/>
              <field name="dividend" type="int32"/>
              <field name="divisor" type="int32"/>
              <field name="quotient" type="double"/>
            </fields>
          </schema>
          <connectors>
            <connector class="fs" name="pub">
              <properties>
                <property name="type"><![CDATA[pub]]></property>
                <property name="fsname"><![CDATA[@ESP_PROJECT_HOME@/test_files/lua_module.csv]]></property>
                <property name="fstype"><![CDATA[csv]]></property>
              </properties>
            </connector>
          </connectors>
        </window-source>
        <window-lua events="create" require="logger" name="Lua">
          <description><![CDATA[The Lua window performs division calculations and references a Lua module that defines the logging functionality.]]></description>
          <schema>
            <fields>
              <field name="id" type="string" key="true"/>
              <field name="dividend" type="int32"/>
              <field name="divisor" type="int32"/>
              <field name="quotient" type="double"/>
            </fields>
          </schema>
          <copy><![CDATA[id,dividend,divisor]]></copy>
          <use><![CDATA[dividend,divisor]]></use>
          <code><![CDATA[function create(data)

    local   e = {}
    local   dividend = data["dividend"]
    local   divisor = data["divisor"]

    if (divisor == 0)
    then
        local   logger = Logger:new("modules.example")
        logger:error("division by 0, "..tostring(dividend).."/"..tostring(divisor))
        return nil
    end

    e["quotient"] = dividend / divisor

    return(e)
end]]></code>
        </window-lua>
      </windows>
      <edges>
        <edge source="Source" target="Lua"/>
      </edges>
    </contquery>
  </contqueries>
</project>