Shell-call

Definition

Many IT applications, within their business process, need to invoke shell command. Gvvcl-shell plug-in can be used to invoke command shell. It is very simple to configure.

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

VulCon / GV Console Configuration

shell-call is the operation that must be configured into VulCon^® or GV Console^® System section, to invoke command shell In order to add an operation shell-call you must define the following fields:

• class: it.greenvulcano.gvesb.virtual.shell.ShellCallOperation (java class that manage shell-call invocation).
• name: this field identify the operation name that you will use in service definition.
• directory: Pathname of the directory in which the command is executed.
• encoding: The encoding with which encode the output of the command in the body of GVBuffer.If not specified, is used the the 'file.encoding' system property value.

The following example shows the configuration generated from VulCon^® or GV Console^® when you configure a shell-call operation:

<?xml version="1.0" encoding="UTF-8"?>
<Channel id-channel="CHANNEL-NAME">
    <shell-call class="it.greenvulcano.gvesb.virtual.shell.ShellCallOperation"
      directory="/home/greenvulcano/script" name="less_file"
      type="call">
     <cmd>less greenvulcano.log</cmd>
    </shell-call>
</Channel>

To use an excelreader-call in a GreenVulcano^® ESB service, you need to define a node of type GVOperationNode in Service section and define in the field operation-name the name defined in excelreader-call operation.

The following example shows the configuration generated from VulCon^® or GV Console^® when you configure an excelreader-call operation in GreenVulcano^® ESB service:

<?xml version="1.0" encoding="UTF-8"?>
<GVServices name="SERVICES" type="module">
    <Groups>
        <Group group-activation="on" id-group="DEFAULT_GRP"/>
    </Groups>
    <Services>
        <Service group-name="DEFAULT_GRP" id-service="SERVICE-NAME"
                 service-activation="on">
            <Client id-system="SYSTEM-NAME" statistics="off" system-activation="on">
                <Operation name="RequestReply" operation-activation="on"
                           out-check-type="none" type="operation">
                    <Participant id-channel="CHANNEL-NAME" id-system="SYSTEM-NAME"/>
                    <Flow first-node="excel_reader" point-x="20" point-y="112">
                        <GVOperationNode class="it.greenvulcano.gvesb.core.flow.GVOperationNode"
                                         id="excel_reader" id-system="DAMA"
                                         input="input" next-node-id="end"
                                         op-type="call"
                                         operation-name="ReadExcelInput"
                                         output="excel_xml" point-x="158"
                                         point-y="112" type="flow-node"/>
                        <GVEndNode class="it.greenvulcano.gvesb.core.flow.GVEndNode"
                                   end-business-process="yes" id="end" op-type="end"
                                   output="excel_xml" point-x="358" point-y="112"
                                   type="flow-node"/>
                    </Flow>
                </Operation>
            </Client>    
        </Service>
    </Services>
</GVServices>

At this point you have configured a service with an excelreader-call operation.

Example

This example shows an XML document generated by a simple Excel sheet (without cols and rows grouping). Given an Excel sheet with the following structure:

ID1	ID2	ID3	ID4	ID5	ID6	ID7
23	23232	23	23333	1	2	3
24	24444	23	23332	1	2	3

excelreader-call generates the following XML:

<?xml version="1.0" encoding="UTF-8"?>
<workbook>
    <sheet number="0">
        <name><![CDATA[Foglio1]]></name>
        <row number="0">
            <col number="0">
                <data><![CDATA[ID1]]></data>
            </col>
            <col number="1">
                <data><![CDATA[ID2]]></data>
            </col>
            <col number="2">
                <data><![CDATA[ID3]]></data>
            </col>
            <col number="3">
                <data><![CDATA[ID4]]></data>
            </col>
            <col number="4">
                <data><![CDATA[ID5]]></data>
            </col>
            <col number="5">
                <data><![CDATA[ID6]]></data>
            </col>
            <col number="6">
                <data><![CDATA[ID7]]></data>
            </col>
        </row>
        <row number="1">
            <col number="0">
                <data><![CDATA[23]]></data>
            </col>
            <col number="1">
                <data><![CDATA[23232]]></data>
            </col>
            <col number="2">
                <data><![CDATA[23]]></data>
            </col>
            <col number="3">
                <data><![CDATA[711]]></data>
            </col>
            <col number="4">
                <data><![CDATA[1]]></data>
            </col>
            <col number="5">
                <data><![CDATA[1]]></data>
            </col>
            <col number="6">
                <data><![CDATA[1]]></data>
            </col>
        </row>
        <row number="2">
            <col number="0">
                <data><![CDATA[23]]></data>
            </col>
            <col number="1">
                <data><![CDATA[711]]></data>
            </col>
            <col number="2">
                <data><![CDATA[23]]></data>
            </col>
            <col number="3">
                <data><![CDATA[23232]]></data>
            </col>
            <col number="4">
                <data><![CDATA[1]]></data>
            </col>
            <col number="5">
                <data><![CDATA[1]]></data>
            </col>
            <col number="6">
                <data><![CDATA[1]]></data>
            </col>
        </row>
    </sheet>
</workbook>

With a ChangeGvBufferNode is possible parsing XML and retrieve any tag and value.

--A.sicignano 16:30, 19 January 2012 (CET)