Generate documents from templates with GroupDocs.Assembly Leave feedback
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GroupDocs.Assembly generates documents from a template and a data source. Unlike the rest of the suite it needs an input you have to author yourself: a template carrying <<[...]>> tags that say where the data goes.
<<[expr]>> inserts a value, <<foreach [x in xs]>>…<</foreach>> repeats a block, and expressions can compute. JSON, XML and spreadsheet fields are referred to by name, for example Name or Client.Name. The output format follows the output file’s extension.
Import the package first, so the Total library is on the classpath, then load the Assembly classes with java.import.
NotePlain JavaScript objects cannot be passed as data sources, because they are not Java objects. Where the Java documentation binds a custom class such asManager, pass JSON, XML or CSV of the same shape, or aDocumentTable.
JsonDataSource reads a JSON file. The name passed to DataSourceInfo is what the template iterates. simple-dataset.docx contains:
<<foreach [in managers]>>Manager: <<[Name]>>
Contracts:
<<foreach [in Contract]>>- <<[Client.Name]>> ($<<[Price]>>)
<</foreach>>
<</foreach>>
The file’s root is an array, so foreach [in managers] walks that array. Nested objects and arrays are reached by name: Contract, then Client.Name.
import '@groupdocs/groupdocs.total';
import java from 'java';
const DocumentAssembler = java.import('com.groupdocs.assembly.DocumentAssembler');
const JsonDataSource = java.import('com.groupdocs.assembly.JsonDataSource');
const DataSourceInfo = java.import('com.groupdocs.assembly.DataSourceInfo');
const managers = new JsonDataSource('manager-data.json');
const assembler = new DocumentAssembler();
assembler.assembleDocument(
'simple-dataset.docx',
'assembly-json.docx',
new DataSourceInfo(managers, 'managers')
);
simple-dataset.docx is the template and manager-data.json is the data. Download simple-dataset.docx and manager-data.json.
Manager: John Smith
Contracts:
- A Company ($1200000)
- B Ltd. ($750000)
- C & D ($350000)
Manager: Tony Anderson
Contracts:
- E Corp. ($650000)
- F & Partners ($550000)
Manager: July James
Contracts:
- G & Co. ($350000)
- H Group ($250000)
- I & Sons ($100000)
- J Ent. ($100000)
The string argument of JsonDataSource is a file path. To assemble JSON held in memory, pass a Java InputStream instead.
XmlDataSource reads the same kind of structure from XML. The template above works unchanged when each manager is a <Manager> element and each contract is a nested <Contract>.
import '@groupdocs/groupdocs.total';
import java from 'java';
const DocumentAssembler = java.import('com.groupdocs.assembly.DocumentAssembler');
const XmlDataSource = java.import('com.groupdocs.assembly.XmlDataSource');
const DataSourceInfo = java.import('com.groupdocs.assembly.DataSourceInfo');
const managers = new XmlDataSource('managers.xml');
const assembler = new DocumentAssembler();
assembler.assembleDocument(
'simple-dataset.docx',
'assembly-xml.docx',
new DataSourceInfo(managers, 'managers')
);
simple-dataset.docx is the template and managers.xml is the data. Download simple-dataset.docx and managers.xml.
Manager: John Smith
Contracts:
- A Company ($1200000)
- B Ltd. ($750000)
- C & D ($350000)
Manager: Tony Anderson
Contracts:
- E Corp. ($650000)
- F & Partners ($550000)
Manager: July James
Contracts:
- G & Co. ($350000)
- H Group ($250000)
- I & Sons ($100000)
- J Ent. ($100000)
DocumentTable reads one worksheet as a table of rows. setFirstRowContainsColumnNames(true) takes the first row as the field names. A space in a heading becomes an underscore, so the column Contract Price is Contract_Price in the template.
contracts-template.docx groups those rows by manager and sums the prices:
Total Contract Prices by Managers
Manager
Total Contract Price
<<foreach [group in contracts.groupBy(c => c.Manager).orderBy(g => g.key)]>><<[group.key]>>
<<[group.sum(c => c.Contract_Price)]>><</foreach>>
import '@groupdocs/groupdocs.total';
import java from 'java';
const DocumentAssembler = java.import('com.groupdocs.assembly.DocumentAssembler');
const DocumentTable = java.import('com.groupdocs.assembly.DocumentTable');
const DocumentTableOptions = java.import('com.groupdocs.assembly.DocumentTableOptions');
const DataSourceInfo = java.import('com.groupdocs.assembly.DataSourceInfo');
const options = new DocumentTableOptions();
options.setFirstRowContainsColumnNames(true);
// First worksheet: Client, Manager, Contract Price
const contracts = new DocumentTable('contracts-data.xlsx', 0, options);
const assembler = new DocumentAssembler();
assembler.assembleDocument(
'contracts-template.docx',
'assembly-spreadsheet.docx',
new DataSourceInfo(contracts, 'contracts')
);
contracts-template.docx is the template and contracts-data.xlsx is the table. Download contracts-template.docx and contracts-data.xlsx.
Total Contract Prices by Managers
Manager
Total Contract Price
John Smith
2300000.0
July James
800000.0
Tony Anderson
1200000.0
GroupDocs.Assembly also reads CSV and database data sources, generates tables, lists and charts from collections, supports conditional blocks and master-detail reports, and can insert hyperlinks and images from the data.
- GroupDocs.Assembly for Node.js via Java documentation — the full product guide
- Template syntax
- Supported file formats
- API reference
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