Filereader-call

Definition

This plug-in allows you to read the contents of a file on the local file system and saves it in the field "object" of output.

GreenVulcano^® ESB provides two different tools, GV Console^® and VulCon^®, to configure all supported plug-ins in GV services.

VulCon / GV Console Configuration

This plug-in reads the local filesystem file's content, and saves it in output GVBuffer object field.

Complete file path is the concatenation of srcPath attribute, with the fileName attribute.

Both of them can contain placeholders, that are expanded at plugin call time.

Attributes srcPath and fileName are subject to these constraints:

• attribute srcPath is overridden by GVFR_DIRECTORY property, if present in current GVBuffer. If property is not defined in GVBuffer, the srcPath attribute in the configuration is used. In both cases, the value of this attribute can be a placeholder, resolved at plugin call time, and the result of the expansion, must result in an absolute pathname, otherwise an exception is thrown. An exception is also thrown if neither the property nor the attribute in configuration are set.
• attribute fileName is overridden by GVFR_FILE_NAME property, if present in current GVBuffer. If property is not defined in GVBuffer, the fileName attribute in the configuration is used. In both cases, the value of this attribute can be a placeholder, resolved at plugin call time, and the result of the expansion, combined with the previous attribute, must result in an existent resource in the local filesystem, otherwise an exception is thrown. An exception is also thrown if neither the property nor the attribute in configuration are set.

The filereader-call Element is used by: Channel, routed-call. The following table shows its attributes:

Attribute	Type	Description
type	fixed	This attribute must assume the value call.
class	fixed	This attribute must assume the value it.greenvulcano.gvesb.virtual.file.reader.FileReader.
name	required	Operation name. Used in the Flow section to associate workflow nodes to VCL operations.
srcPath	required	This value can be static or dynamic, containing placeholders that could be replaced at plugin call time. This is a default value, and is used if the property GVFR_DIRECTORY is not defined in the current GVBuffer.
fileName	required	This value can be static or dynamic, containing placeholders that could be replaced at plugin call time. This is a default value, and is used if the property GVFR_FILE_NAME is not defined in the current GVBuffer.

Might contain the following sub-elements:

• Description
• xml-processor

xml-processor

If this element is specified, the plugin will read the file directly parsed as an XML.

The xml-processor Element is used by:

• filereader-call
• rsh-filereader-call

Its attributes are:

Attribute	Type	Description
as-xml	optional	If true the file is parsed as an XML. Default is false.
use-axiom	optional	If true uses AXIOM instead of DOM to parse the file. Default is false.
validating	optional	If true the XML representing the file is validated. This option applies only if as-xml is true. Default is false.
namespace-aware	optional	If true the DOM keeps informations about the declared namespaces on the file. This option applies only if as-xml is true. Default is false.

How To

Suppose you want to read a file present in the ${{gv.app.home}}/TEST/TESTFS/TestXML/input folder. Right-clicking on Channel, insert after, FileReader-call, it adds a new element FileReader-call.

Filereader_call attributes

Clicking above this new element, in the Properties view, you can set its attributes:

• Class and type are passed by default
• Name, in this example takes the value ReadFile
• file-name is passed as a parameter through the property FILE_NAME (see placeholders).

The respective part of the GVCore.xml file becomes:

<System id-system="GVESB" system-activation="on">
    <Channel id-channel="TEST_CHANNEL_FILE">                    
        <filereader-call class="it.greenvulcano.gvesb.virtual.file.reader.FileReader"
            fileName="ognl{{property[&apos;FILE_NAME&apos;]}}"
            name="ReadFile"
            srcPath="${{gv.app.home}}/TEST/TESTFS/TestXML/input"
            type="call"/>                                     
    </Channel>
</System>

associated to the Service ValidateSingleXMLFile.

<Service group-name="DEFAULT_GRP" id-service="ValidateSingleXMLFile" service-activation="on" statistics="off">
   <Operation name="Request" operation-activation="on" out-check-type="none" type="operation">
      <Participant id-channel="TEST_CHANNEL_FILE" id-system="GVESB"/>
      <Flow first-node="fillProperties" point-x="9" point-y="31">
           <ChangeGVBufferNode class="it.greenvulcano.gvesb.core.flow.ChangeGVBufferNode"
                id="fillProperties" input="node" next-node-id="read_validate_file"
                op-type="change GVBuffer" output="input" point-x="-25" point-y="163" type="flow-node">
                 <ChangeGVBuffer clear-data="false">
                      <OGNLScript>property[&apos;FILE_NAME&apos;] =                                           
                                   @it.greenvulcano.configuration.XMLConfig@get(object,&apos;@name&apos;) 
                      </OGNLScript>
                 </ChangeGVBuffer>
           </ChangeGVBufferNode>
           <GVOperationNode class="it.greenvulcano.gvesb.core.flow.GVOperationNode"
                  id="read_validate_file" id-system="GVESB"
                  input="input" next-node-id="end"
                  op-type="call" operation-name="ReadFile"
                  output="payload" point-x="160" point-y="165"
                  type="flow-node">
                      <OutputServices>
                          <xml-validation-service internal="yes" type="service">
                              <xml-validation-call class="it.greenvulcano.gvesb.virtual.internal.xml.XMLValidationCallOperation"
                                      default-xsd="ValidateXML.xsd"
                                      name="ValidateXML"
                                      return-dom="false" type="call"
                                      xsd-policy="force-default"/>
                          </xml-validation-service>
                      </OutputServices>
           </GVOperationNode>
           <GVEndNode class="it.greenvulcano.gvesb.core.flow.GVEndNode"
                 end-business-process="yes" id="end" op-type="end"
                 output="input" point-x="729" point-y="33"
                 type="flow-node"/>
       </Flow>
   </Operation>
</Service>

The first operation node, ChangeGVBufferNode: fillProperties is used for setting the property FILE_NAME containing the name of the file to be read. Successively, it is added the GVOperationNode: read_validate_file who calls the operation filereader_call: ReadFile, and internally, it is define an OutputServices, xml-validation-service and xml-validation-call: ValidateXML in order to validate the XML file FILE_NAME using ValidateXML.xsd.