Generate docx documents from templates, in Node or in the browser.
npm install easy-template-xtypescript
import * as fs from 'fs';
import { TemplateHandler } from 'easy-template-x';
// 1. read template file
const templateFile = fs.readFileSync('myTemplate.docx');
// 2. process the template
const data = {
posts: [
{ author: 'Alon Bar', text: 'Very important\ntext here!' },
{ author: 'Alon Bar', text: 'Forgot to mention that...' }
]
};
const handler = new TemplateHandler();
const doc = await handler.process(templateFile, data);
// 3. save output
fs.writeFileSync('myTemplate - output.docx', doc);
`
Input:
!input template
Output:
!output document
Browser Example
The following example produces the same output while running in the browser.
Notice that the actual template processing (step 2) is exactly the same as in the previous Node example.
`typescript
import { TemplateHandler } from 'easy-template-x';
// 1. read template file
// (in this example we're loading the template by performing
// an AJAX call using the fetch API, another common way to
// get your hand on a Blob is to use an HTML File Input)
const response = await fetch('http://somewhere.com/myTemplate.docx');
const templateFile = await response.blob();
// 2. process the template
const data = {
posts: [
{ author: 'Alon Bar', text: 'Very important\ntext here!' },
{ author: 'Alon Bar', text: 'Forgot to mention that...' }
]
};
const handler = new TemplateHandler();
const doc = await handler.process(templateFile, data);
// 3. save output
saveFile('myTemplate - output.docx', doc);
function saveFile(filename, blob) {
// see: https://stackoverflow.com/questions/19327749/javascript-blob-filename-without-link
// get downloadable url from the blob
const blobUrl = URL.createObjectURL(blob);
// create temp link element
let link = document.createElement("a");
link.download = filename;
link.href = blobUrl;
// use the link to invoke a download
document.body.appendChild(link);
link.click();
// remove the link
setTimeout(() => {
link.remove();
window.URL.revokeObjectURL(blobUrl);
link = null;
}, 0);
}
`
Live Demo
Checkout this live demo on CodeSandbox 😎
Plugins
easy-template-x uses a plugin model to support it's various template manipulation capabilities. There are some built-in plugins and you can also write your own custom plugins if required.
These are the plugins that comes bundled with easy-template-x:
- Text plugin - For simple text replacement.
- Loop plugin - For iterating text, table rows, table columns and list rows and for simple conditions.
- Image plugin - For embedding images.
- Link plugin - For hyperlinks creation.
- Chart plugin - For handling charts.
- Raw xml plugin - For custom xml insertion.
$3
The most basic plugin. Replaces a single tag with custom text. Preserves the original text style.
Input template:
!input template
Input data:
`json
{
"First Tag": "Quis et ducimus voluptatum\nipsam id.",
"Second Tag": "Dolorem sit voluptas magni dolorem molestias."
}
`
Output document:
!output document
$3
Iterates text, table rows, table columns and lists.
Requires an opening tag that starts with # and a closing tag that starts with / (configurable).
Note: The closing tag does not need to have the same name as the opening tag, or a name at all. This will work {#loop}{/loop}, but also this {#loop}{/} and even this {#loop}{/something else}.
Input template:
!input template
Input data:
`json
{
"Beers": [
{ "Brand": "Carlsberg", "Price": 1 },
{ "Brand": "Leaf Blonde", "Price": 2 },
{ "Brand": "Weihenstephan", "Price": 1.5 }
]
}
`
Output document:
!output document
#### Conditions
You can render content conditionally depending on a boolean value using the same syntax used for loops.
The example below shows two lines being rendered, each with different content depending on the truthy value.
Input template:
!input template
Input data:
`javascript
{
lines: [
{ visible: true },
{ invisible: true }
]
}
`
Output document:
!output document
#### Nested Conditions
Nested conditions are also supported, so you can nest other tags including loop tags and even other conditions in them. When doing so remember to format your data accordingly. See the example below for clarification:
Input template:
!input template
Input data:
Notice how even though name and members are nested in the template under the show condition their values are adjacent to it in the input data.
`javascript
{
"teams": [
{
show: true,
name: "A-Team",
members: [
{ name: "Hannibal" },
{ name: "Face" },
{ name: "Murdock" },
{ name: "Baracus" },
]
},
{
show: false,
name: "B-Team",
members: [
{ name: "Alice" },
{ name: "Bob" },
{ name: "Charlie" },
{ name: "Dave" },
]
}
],
}
`
Output document:
!output document
_If you are looking for a yet more powerful conditional syntax see the alternative syntax section._
#### Controlling loop behavior
The loop plugin uses some heuristics to determine the right behavior in each
case (i.e. when to loop over rows, columns, paragraphs, etc.). You can control this behavior
explicitly through the loopOver option as explain below.
##### Default behavior
The default heuristics are as follows:
1. If both loop tags are inside the same table cell - the plugin assumes you want to repeat the cell content, not the row or column.
2. If both loop tags are in the same column - the plugin will repeat the column.
3. If both loop tags are inside a table - the plugin will repeat the relevant table rows.
4. If both loop tags are in a list - the plugin will repeat the relevant list items.
5. Otherwise - the plugin will use a naive approach for repeating the content in between the loop tags.
##### Changing the default
To use a different behavior than the default one you can use the loopOver
option. Supported values are: row, column and content.
Note: This option controls conditions too.
For instance, given this data:
`javascript
{
students: [
{ name: "Alice" },
{ name: "Bob" }
]
}
`
You can use this syntax:
!input template
Or this syntax:
!input template
Or this syntax:
!input template
The first will produce this document:
!output document
The second will produce this document:
!output document
And the third will produce this document:
!output document
$3
Embed images into the document.
The image plugin supports two modes:
1. Text tag replacement
2. Image placeholder replacement
#### Text tag replacement
Insert inline images by placing tags in the document body.
Input template example:
!input template
#### Image placeholder replacement
Replace existing placeholder images while preserving their size, position, and styling.
Note: You can use any image you want as the placeholder.
Input template example:
!input template
To let easy-template-x know you want to replace the placeholder image, insert a tag in it's alt text:
!alt text context menu
!alt text panel
#### Data and output
The data and resulting output are the same for both modes.
Input data:
`javascript
{
"Kung Fu Hero": {
_type: "image",
source: fs.readFileSync("hero.png"),
format: MimeType.Png,
width: 200, // Required for text tags, optional for placeholders
height: 200, // Required for text tags, optional for placeholders
altText: "Kung Fu Hero", // Optional
transparencyPercent: 80 // Optional
}
}
`
Output document:
!output document
$3
Inserts hyperlinks into the document.
Like text tags link tags also preserve their original style.
Input template:
!input template
Input data:
`javascript
{
"easy": {
_type: 'link',
text: 'super easy', // Optional - if not specified the target property will be used
target: 'https://github.com/alonrbar/easy-template-x'
}
}
`
Output document:
!output document
$3
To use charts in templates, put a placeholder chart and place a tag in its title, like so:
!chart placeholder
Generally speaking, the charts preserve their original settings and style with
some configurations also available through the input json data.
easy-template-x try to keep the same terminology used by MS Word. Therefore,
while the exact input data schema depends on the chart type, the main terms
are common to most:
- Categories are the values of the X axis.
- Series are the values of the Y axis.
Take a look at the examples below to get a better understanding of how chart
tags behave.
#### Line, bar & column charts
Line, bar & column charts all uses the same input data format.
The example below shows 4 charts in the same template: Line chart, Column chart, Bar chart and Stacked Column chart. In this example all of the charts use the same input data (the MyChart tag data) but you can of course use a different tag for each chart.
Notice how the end result ignores the placeholder data and matches our input data instead.
Note that you are not limited to use the same number of categories or series as the placeholder chart. This specific example uses less series than the placeholder (2 instead of 3) but you can just as easily add more series or change the number of categories.
Input template:
!input template
Input data:
`javascript
{
MyChart: {
_type: "chart",
title: "Easy Chart", // Optional
categories: {
names: ["Q1", "Q2", "Q3", "Q4"]
},
series: [
{
name: "Earnings", // Optional
color: "#34d399", // Optional
values: [100, 210, 150, 170]
},
{
name: "Expenses",
color: "#f87171",
values: [170, 165, 169, 155]
},
],
}
}
`
Output document:
!output document
#### Pie & doughnut charts
Pie & doughnut uses the same input data format as line, bar and column chart,
except they expect a single series.
The example below shows 4 charts in the same template: 2 pie charts and 2 doughnut charts, each with a different style.
Input template:
!input template
Input data:
`javascript
{
Chart1: {
_type: "chart",
title: "Easy Chart", // Optional
categories: {
names: ["Q1", "Q2", "Q3", "Q4"]
},
series: [
{ values: [100, 210, 150, 170] },
],
}
}
`
Output document:
!output document
#### Scatter chart
Scatter chart do not have a categories property. Instead, each of their values requires an x and a y properties.
Input template:
!input template
Input data:
`javascript
{
scatter: {
_type: "chart",
title: "Easy Scatter Chart", // Optional
series: [
{
name: "Earnings", // Optional
color: "#34d399", // Optional
values: [
{ x: 1, y: 310 },
{ x: 3, y: 450 },
{ x: 4, y: 200 },
{ x: 6, y: 200 },
],
},
{
name: "Expenses",
color: "#f87171",
values: [
{ x: 1, y: 410 },
{ x: 2, y: 450 },
{ x: 3, y: 200 },
{ x: 5, y: 350 },
],
},
],
}
}
`
Output document:
!output document
#### Bubble chart
Bubble charts are very similar to scatter charts but they have an additional
size property (notice the placeholder chart should be a bubble chart, not a
scatter chart).
Input template:
!input template
Input data:
`javascript
{
bubble: {
_type: "chart",
title: "Bubble Chart", // Optional
series: [
{
name: "Earnings", // Optional
color: "#34d399", // Optional
values: [
{ x: 1, y: 10, size: 10 },
{ x: 2, y: 10, size: 20 },
{ x: 3, y: 8, size: 40 },
{ x: 4, y: 8, size: 30 },
],
},
{
name: "Expenses",
color: "#f87171",
values: [
{ x: 1, y: 4, size: 40 },
{ x: 2, y: 4, size: 20 },
{ x: 3, y: 3, size: 30 },
],
},
],
}
}
`
Output document:
!output document
$3
Add custom xml into the document to be interpreted by Word.
Tip:
You can add page breaks using this plugin and the following xml markup:
Input template:
!input template
Input data:
`javascript
{
"Dont worry be happy": {
_type: 'rawXml',
xml: '
replaceParagraph: false, // Optional - should the plugin replace an entire paragraph or just the tag itself
}
}
`
Output document:
!output document
$3
To write a plugin inherit from the TemplatePlugin class.
The base class provides two methods you can implement and a set of utilities to
make it easier to do the actual xml modification.
_To better understand the internal structure of Word documents check out this excellent source._
Example plugin implementation (this is a simplified example of the RawXmlPlugin - read the full source here):
`typescript
import { officeMarkup, xml } from "easy-template-x";
/**
* A plugin that inserts raw xml to the document.
*/
export class RawXmlPlugin extends TemplatePlugin {
// Declare the unique "content type" this plugin handles
public readonly contentType = 'rawXml';
// Plugin logic goes here:
public simpleTagReplacements(tag: Tag, data: ScopeData): void {
// Get the value to use from the input data.
const value = data.getScopeData();
if (value && typeof value.xml === 'string') {
// Tag.xmlTextNode always reference the actual xml text node.
// In MS Word each text node is wrapped by a node so we retrieve that.
const wordTextNode = officeMarkup.query.containingTextNode(tag.xmlTextNode);
// If the input data contains an "xml" string property, parse it and insert
// the content next to the placeholder tag.
const newNode = xml.parser.parse(value.xml);
xml.modify.insertBefore(newNode, wordTextNode);
}
// Remove the placeholder tag.
officeMarkup.modify.removeTag(tag);
}
}
`
The content type that this plugin expects to see is:
`typescript
export interface RawXmlContent extends PluginContent {
_type: 'rawXml';
xml: string;
}
`
Listing tags
You can get the list of tags in a template by calling the parseTags method as follows:
`typescript
import { TemplateHandler } from 'easy-template-x';
const templateFile = fs.readFileSync('myTemplate.docx');
const handler = new TemplateHandler();
const tags = await handler.parseTags(templateFile);
`
Scope resolution
easy-template-x supports tag data scoping. That is, you can reference
"shallow" data from within deeper in the hierarchy similarly to how you can
reference an outer scope variables from within a function in JavaScript. You can
leverage this property to declare "top level" data (your logo and company name
or some useful xml snippets like page breaks, etc.) to be used anywhere in the
document.
Input template:
(notice that we are using the "Company" tag inside the "Employees" loop)
!input template
Input data:
(notice that the "Company" data is declared outside the "Employees" loop, in it's so
called "outer scope")
`javascript
{
"Company": "Contoso Ltd.",
"Employees": [
{ "Surname": "Gates", "Given name": "William" },
{ "Surname": "Nadella", "Given name": "Satya" },
]
}
`
Output document:
!output document
Extensions
While most document manipulation can be achieved using plugins, there are some cases where a more powerful tool is required. In order to extend the document manipulation process you can specify extensions that will be run before and/or after the standard template processing.
To write an extension inherit from the TemplateExtension class.
By default no extension is loaded. Extensions and the order they run in are specified via the TemplateHandlerOptions.
`typescript
const handler = new TemplateHandler({
extensions: {
afterCompilation: [
new DataBindingExtension()
]
}
});
`
$3
The following extensions were developed by the community.
Want to see your extension here? Submit a pull request or open an issue.
- Data Binding Extension - The easy-template-x-data-binding extension supports updating custom XML parts inside Word documents.
Template handler options
You can configure the template handler behavior by passing an options object to it's constructor.
Below is the list of options along with their types and default values:
`typescript
const handler = new TemplateHandler({
plugins: createDefaultPlugins(), // TemplatePlugin[]
defaultContentType: TEXT_CONTENT_TYPE, // string
containerContentType: LOOP_CONTENT_TYPE, // string
delimiters: { // Partial
tagStart: "{",
tagEnd: "}",
containerTagOpen: "#",
containerTagClose: "/",
tagOptionsStart: "[",
tagOptionsEnd: "]"
},
maxXmlDepth: 20,
extensions: { // ExtensionOptions
beforeCompilation: undefined, // TemplateExtension[]
afterCompilation: undefined // TemplateExtension[]
},
scopeDataResolver: undefined // ScopeDataResolver
})
`
$3
To use custom tag delimiters and container marks (used for loops and conditions) specify the delimiters option of the template handler.
For instance, to change from {#open loop} and {/close loop} to {{>>open loop}} and {{<typescript
const handler = new TemplateHandler({
delimiters: {
tagStart: "{{",
tagEnd: "}}",
containerTagOpen: ">>",
containerTagClose: "<<"
},
})
`
$3
Custom scope data resolvers gives the developer a way to hook into easy-template-x in order to change how it interprets the tag syntax.
For instance, to use Angular-like expressions you can import easy-template-x-angular-expressions by doing the following:
`typescript
import { createResolver } from "easy-template-x-angular-expressions"
const handler = new TemplateHandler({
scopeDataResolver: createResolver()
})
`
This allows the use of advanced syntax expressions such as:
!output document
Supported Binary Formats
The library supports the following binary formats:
- Blob (browser)
- Buffer (node)
- ArrayBuffer (browser and node)
Note - Internal API
In addition to what's described here in the readme file the library exports many
more types and functions. While you are free to use them as you see fit please note
that anything not documented in the readme file is considered an internal
implementation detail and may break between minor versions, use at your own
risk.
Philosophy
This library was originally developed as part of an app for non-English speaking k-12 teachers. As such it assumes the template editors do not necessarily have technical background and certainly no programming experience.
In order to stay friendly for such potential users it keeps the template syntax as simple as possible, limiting the required knowledge to {tags} and {#loop tags}{/loop tags} alone (and can be customized to support an alternative, potentially simpler syntax, such as {>>loop tags}{< or {اسم المعلم}`.