tFileInputXML

tFileInputXML Properties

Component family	XML or File/Input
Function	tFileInputXML reads an XML structured file and extracts data row by row. If you have subscribed to one of the Talend solutions with Big Data, you are able to use this component in a Talend Map/Reduce Job to generate Map/Reduce code. For further information, see tFileInputXML in Talend Map/Reduce Jobs
Purpose	Opens an XML structured file and reads it row by row to split them up into fields then sends fields as defined in the Schema to the next component, via a Row link.
Basic settings	Property type	Either Built-in or Repository.
		Built-in: No property data stored centrally.
		Repository: Select the Repository file where Properties are stored. The following fields are pre-filled in using fetched data.
	Schema and Edit Schema	A schema is a row description, it defines the number of fields that will be processed and passed on to the next component. The schema is either built-in or remote in the Repository. Click Edit schema to make changes to the schema. If the current schema is of the Repository type, three options are available: View schema: choose this option to view the schema only. Change to built-in property: choose this option to change the schema to Built-in for local changes. Update repository connection: choose this option to change the schema stored in the repository and decide whether to propagate the changes to all the Jobs upon completion. If you just want to propagate the changes to the current Job, you can select No upon completion and choose this schema metadata again in the [Repository Content] window.
		Built-in: The schema will be created and stored locally for this component only. Related topic: see Talend Studio User Guide.
		Repository: The schema already exists and is stored in the Repository, hence can be reused in various projects and job flowcharts. Related topic: see Talend Studio User Guide.
	File name/Stream	File name: Name and path of the file to be processed. Stream: The data flow to be processed. The data must be added to the flow in order for tFileInputXML to fetch these data via the corresponding representative variable. This variable could be already pre-defined in your Studio or provided by the context or the components you are using along with this component, for example, the INPUT_STREAM variable of tFileFetch; otherwise, you could define it manually and use it according to the design of your Job, for example, using tJava or tJavaFlex. In order to avoid the inconvenience of hand writing, you could select the variable of interest from the auto-completion list (Ctrl+Space) to fill the current field on condition that this variable has been properly defined. Related topic to the available variables: see Talend Studio User Guide. Related scenario to the input stream, see Scenario 2: Reading data from a remote file in streaming mode.
	Loop XPath query	Node of the tree, which the loop is based on.
	Mapping	Column: Columns to map. They reflect the schema as defined in the Schema type field. XPath Query: Enter the fields to be extracted from the structured input. Get nodes: Select this check box to recuperate the XML content of all current nodes specified in the Xpath query list, or select the check box next to specific XML nodes to recuperate only the content of the selected nodes. These nodes are important when the output flow from this component needs to use the XML structure, for example, the Document data type. For further information about the Document type, see Talend Studio User Guide. Note The Get Nodes option functions in the DOM4j and SAX modes, although in SAX mode namespaces are not supported. For further information concerning the DOM4j and SAX modes, please see the properties noted in the Generation mode list of the Advanced Settings tab.
	Limit	Maximum number of rows to be processed. If Limit = 0, no row is read nor processed. If -1, all rows are read or processed.
	Die on error	Select this check box to stop the execution of the Job when an error occurs. Clear the check box to skip any rows on error and complete the process for error-free rows. When errors are skipped, you can collect the rows on error using a Row > Reject link.
Advanced settings	Ignore DTD file	Select this check box to ignore the DTD file indicated in the XML file being processed.
	Advanced separator (for number)	Select this check box to change data separator for numbers: Thousands separator: define the separators to use for thousands. Decimal separator: define the separators to use for decimals.
	Ignore the namespaces	Select this check box to ignore name spaces. Generate a temporary file: click the three-dot button to browse to the XML temporary file and set its path in the field.
	Use Separator for mode Xerces	Select this check box if you want to separate concatenated children node values. Note This field can only be used if the selected Generation mode is Xerces. The following field displays: Field separator: Define the delimiter to be used to separate the children node values.
	Encoding	Select the encoding from the list or select Custom and define it manually. This field is compulsory for database data handling.
	Generation mode	From the drop-down list select the generation mode for the XML file, according to the memory available and the desired speed: Slow and memory-consuming (Dom4j) Note This option allows you to use dom4j to process the XML files of high complexity. Memory-consuming (Xerces). Fast with low memory consumption (SAX)
	Validate date	Select this check box to check the date format strictly against the input schema.
	tStatCatcher Statistics	Select this check box to gather the Job processing metadata at a Job level as well as at each component level.
Global Variables	ERROR_MESSAGE: the error message generated by the component when an error occurs. This is an After variable and it returns a string. This variable functions only if the Die on error check box is cleared, if the component has this check box. NB_LINE: the number of rows processed. This is an After variable and it returns an integer. A Flow variable functions during the execution of a component while an After variable functions after the execution of the component. To fill up a field or expression with a variable, press Ctrl + Space to access the variable list and choose the variable to use from it. For further information about variables, see Talend Studio User Guide.
Usage	tFileInputXML is for use as an entry componant. It allows you to create a flow of XML data using a Row > Main link. You can also create a rejection flow using a Row > Reject link to filter the data which doesn’t correspond to the type defined. For an example of how to use these two links, see Scenario 2: Extracting correct and erroneous data from an XML field in a delimited file.
Log4j	The activity of this component can be logged using the log4j feature. For more information on this feature, see Talend Studio User Guide. For more information on the log4j logging levels, see the Apache documentation at http://logging.apache.org/log4j/1.2/apidocs/org/apache/log4j/Level.html.
Limitation	n/a

tFileInputXML in Talend
Map/Reduce Jobs

Warning

The information in this section is only for users that have subscribed to one of
the Talend solutions with Big Data and is not applicable to
Talend Open Studio for Big Data users.

In a Talend Map/Reduce Job, tFileInputXML, as well as the whole Map/Reduce Job using it, generates
native Map/Reduce code. This section presents the specific properties of tFileInputXML when it is used in that situation. For further
information about a Talend Map/Reduce Job, see the Talend Big Data Getting Started Guide.

Component family	MapReduce/Input
Basic settings	Property type	Either Built-in or Repository.
		Built-in: No property data stored centrally.
		Repository: reuse properties stored centrally under the Hadoop Cluster node of the Repository tree. The fields that come after are pre-filled in using the fetched data. For further information about the Hadoop Cluster node, see the Getting Started Guide.
	Schema and Edit Schema	A schema is a row description, it defines the number of fields that will be processed and passed on to the next component. The schema is either built-in or remote in the Repository. Click Edit schema to make changes to the schema. If the current schema is of the Repository type, three options are available: View schema: choose this option to view the schema only. Change to built-in property: choose this option to change the schema to Built-in for local changes. Update repository connection: choose this option to change the schema stored in the repository and decide whether to propagate the changes to all the Jobs upon completion. If you just want to propagate the changes to the current Job, you can select No upon completion and choose this schema metadata again in the [Repository Content] window.
		Built-in: The schema will be created and stored locally for this component only. Related topic: see Talend Studio User Guide.
		Repository: The schema already exists and is stored in the Repository, hence can be reused in various projects and job flowcharts. Related topic: see Talend Studio User Guide.
	Folder/File	Browse to, or enter the directory in HDFS where the data you need to use is. If the path you set points to a folder, this component will read all of the files stored in that folder, for example, /user/talend/in; if sub-folders exist, the sub-folders are automatically ignored unless you define the path like /user/talend/in/. If you want to specify more than one files or directories in this field, separate each path using a coma (,). If the file to be read is a compressed one, enter the file name with its extension; then ttFileInputXML* automatically decompresses it at runtime. The supported compression formats and their corresponding extensions are: DEFLATE: .deflate gzip: .gz bzip2: .bz2 LZO: .lzo Note that you need to ensure you have properly configured the connection to the Hadoop distribution to be used in the Hadoop configuration tab in the Run view.
	Element to extract	Enter the element from which you need to read the contents and the child elements of the input XML data. The element defined in this field is used at the root node of any XPath specified within this component. This element helps define the atomic units of the XML data to be used so that however big the original document is or wherever the input is split, the rows within this element can be correctly distributed to the mapper tasks. Note that any content outside this element is ignored and the child elements of this element cannot contain this element itself.
	Loop XPath query	Node of the tree, which the loop is based on. Note its root is the element you have defined in the Element to extract field.
	Mapping	Column: Columns to map. They reflect the schema as defined in the Schema type field. XPath Query: Enter the fields to be extracted from the structured input. Get nodes: Select this check box to recuperate the XML content of all current nodes specified in the Xpath query list, or select the check box next to specific XML nodes to recuperate only the content of the selected nodes. These nodes are important when the output flow from this component needs to use the XML structure, for example, the Document data type. For further information about the Document type, see Talend Studio User Guide.
	Die on error	Select this check box to stop the execution of the Job when an error occurs. Clear the check box to skip any rows on error and complete the process for error-free rows. When errors are skipped, you can collect the rows on error using a Row > Reject link.
Advanced settings	Ignore the namespaces	Select this check box to ignore name spaces.
	Custom encoding	You may encounter encoding issues when you process the stored data. In that situation, select this check box to display the Encoding list. Select the encoding from the list or select Custom and define it manually. This field is compulsory for database data handling.
Global Variables	ERROR_MESSAGE: the error message generated by the component when an error occurs. This is an After variable and it returns a string. This variable functions only if the Die on error check box is cleared, if the component has this check box. A Flow variable functions during the execution of a component while an After variable functions after the execution of the component. To fill up a field or expression with a variable, press Ctrl + Space to access the variable list and choose the variable to use from it. For further information about variables, see Talend Studio User Guide.
Usage	Because of the characteristics of the MapReduce framework, the Map/Reduce version of tFileInputXML does not support none of the following XML parsers: the DOM-based parsers, the SAX-based parsers and the streaming-based parsers. In a Talend Map/Reduce Job, it is used as a start component and requires a transformation component as output link. The other components used along with it must be Map/Reduce components, too. They generate native Map/Reduce code that can be executed directly in Hadoop. Once a Map/Reduce Job is opened in the workspace, tFileInputXML as well as the MapReduce family appears in the Palette of the Studio. Note that in this documentation, unless otherwise explicitly stated, a scenario presents only Standard Jobs, that is to say traditional Talend data integration Jobs, and non Map/Reduce Jobs.
Hadoop Connection	You need to use the Hadoop Configuration tab in the Run view to define the connection to a given Hadoop distribution for the whole Job. This connection is effective on a per-Job basis.

Scenario 1: Reading and extracting data from an XML structure

This scenario describes a basic Job that reads a defined XML directory and extracts
specific information and outputs it on the Run console
via a tLogRow component.

Drop tFileInputXML and tLogRow from the Palette to the
design workspace.
Connect both components together using a Main Row
link.
Double-click tFileInputXML to open its
Basic settings view and define the
component properties.
As the street dir file used as input file has been previously defined in the
Metadata area, select Repository as Property type. This way, the properties are
automatically leveraged and the rest of the properties fields are filled in
(apart from Schema). For more information regarding the metadata
creation wizards, see Talend Studio User
Guide.
Select the same way the relevant schema in the Repository metadata list.
Edit schema if you want to make any change
to the schema loaded.
The Filename shows the structured file to be
used as input
In Loop XPath query, change if needed the
node of the structure where the loop is based.
On the Mapping table, fill the fields to be
extracted and displayed in the output.
If the file size is consequent, fill in a Limit of rows to be read.
Enter the encoding if needed then double-click on tLogRow to define the separator character.
Save your Job and press F6 to execute
it.

The fields defined in the input properties are extracted from the XML structure and
displayed on the console.

Scenario 2: Extracting erroneous XML data via a reject flow

This Java scenario describes a three-component Job that reads an XML file and:

first, returns correct XML data in an output XML file,
and second, displays on the console erroneous XML data which type does not
correspond to the defined one in the schema.

Drop the following components from the Palette to the design workspace: tFileInputXML, tFileOutputXML
and tLogRow.

Right-click tFileInputXML and select
Row > Main in the contextual menu and then click tFileOutputXML to connect the components together.

Right-click tFileInputXML and select
Row > Reject in the contextual menu and then click tLogRow to connect the components together using a
reject link.
Double-click tFileInputXML to display the
Basic settings view and define the
component properties.
In the Property Type list, select Repository and click the three-dot button next to the
field to display the [Repository Content]
dialog box where you can select the metadata relative to the input
file if you have already stored it in the File xml node under the Metadata folder of the Repository tree view. The fields that follow are automatically
filled with the fetched data. If not, select Built-in and fill in the fields that follow manually.

For more information about storing schema metadat in the Repository tree
view, see Talend Studio User Guide.
In the Schema Type list, select Repository and click the three-dot button to open the
dialog box where you can select the schema that describe the structure of the
input file if you have already stored it in the Repository tree view. If not, select Built-in and click the three-dot button next to Edit schema to open a dialog box where you can define
the schema manually.

The schema in this example consists of five columns: id,
CustomerName, CustomerAddress, idState and
id2.
Click the three-dot button next to the Filename field and browse to the XML file you want to
process.
In the Loop XPath query, enter between
inverted commas the path of the XML node on which to loop in order to retrieve
data.

In the Mapping table, Column is automatically populated with the defined
schema.

In the XPath query column, enter between
inverted commas the node of the XML file that holds the data you want to extract
from the corresponding column.
In the Limit field, enter the number of lines
to be processed, the first 10 lines in this example.
Double-click tFileOutputXML to display its
Basic settings view and define the
component properties.
Click the three-dot button next to the File
Name field and browse to the output XML file you want to collect
data in, customer_data.xml in this example.

In the Row tag field, enter between inverted
commas the name you want to give to the tag that will hold the recuperated
data.

Click Edit schema to display the schema
dialog box and make sure that the schema matches that of the preceding
component. If not, click Sync columns to
retrieve the schema from the preceding component.
Double-click tLogRow to display its Basic settings view and define the component
properties.

Click Edit schema to open the schema dialog
box and make sure that the schema matches that of the preceding component. If
not, click Sync columns to retrieve the schema
of the preceding component.

In the Mode area, select the Vertical option.
Save your Job and press F6 to execute
it.

The output file customer_data.xml holding the correct XML data is
created in the defined path and erroneous XML data is displayed on the console of the
Run view.

Document get from Talend https://help.talend.com

Thank you for watching.

Docs 5.x

0 Comments

Inline Feedbacks

View all comments

tFileInputXML – Docs for ESB 5.x

tFileInputXML

tFileInputXML Properties

Note

Note

Note

tFileInputXML in Talend
Map/Reduce Jobs

Warning

Scenario 1: Reading and extracting data from an XML structure

Scenario 2: Extracting erroneous XML data via a reject flow

My Website Links

Tags

tFileInputXML

tFileInputXML Properties

Note

Note

Note

tFileInputXML in Talend Map/Reduce Jobs

Warning

Scenario 1: Reading and extracting data from an XML structure

Scenario 2: Extracting erroneous XML data via a reject flow

tFileInputXML in Talend
Map/Reduce Jobs