APITemplate.io Filters

These filters and functions are custom to APITemplate.io and extend what standard Jinja2 offers. They let you generate QR codes, barcodes, HTML tables, format dates, and more directly inside your templates.

render_qrcode

Converts a value into a QR code image.

Syntax:

{{ value | render_qrcode(style="css styles") }}

Example:

{
  "website": "https://apitemplate.io",
  "email": "hello@apitemplate.io"
}

{{ website | render_qrcode(style='width: 100px; height: 100px; background: white;') }}
QR code for {{ website }}

Parameters:

Parameter	Description
style	CSS styles applied to the QR code image

render_barcode

Converts a value into a barcode image.

Syntax:

{{ value | render_barcode(type="barcode_type", style="css styles") }}

Example:

{
  "document_id": "889856789012"
}

{{ document_id | render_barcode(type='ean13', style='height: 100px;', quiet_zone=0, font_size=10, text_distance=5, module_width=0.2, module_height=15.0) }}
Barcode for {{ document_id }}

Parameters:

Parameter	Description	Default
type	Barcode format (required) — see supported types below	—
style	CSS styles	—
quiet_zone	Distance from border to barcode (mm)	0
font_size	Text font size (pt). Set to 0 to hide text	10
text_distance	Distance between barcode and text (mm)	5.0
module_width	Width of one barcode module (mm)	0.2
module_height	Height of barcode modules (mm)	15.0

Supported barcode types:

Type	Description
ean8	EAN8
ean13 / ean	EAN13
gtin / ean14	EAN14
jan	JAN
upc / upca	UPCA
isbn / isbn13 / gs1	ISBN13
isbn10	ISBN10
issn	ISSN
code39	Code39
pzn	PZN
code128	Code128
itf	ITF
gs1_128	GS1-128

render_table

Converts a JSON array into an HTML table.

Syntax:

{{ json_array | render_table(table_class="css class") }}

Example:

{
  "title": "Product list",
  "items": [
    {"item_name": "Product 1", "price": "USD 200.00"},
    {"item_name": "Product 2", "price": "USD 300.00"}
  ]
}

{{ items | render_table(table_class='table') }}

Parameters:

Parameter	Description
table_class	CSS class applied to the <table> element

json

Renders a JSON object as JSON in the HTML output. Useful for debugging or displaying raw data.

Syntax:

{{ json_object | json }}

Example:

<pre>{{ my_data | json }}</pre>

strptime

Parses a date string into a datetime object. Typically used together with strftime to reformat dates.

Syntax:

{{ strptime(date_string, format) }}

Example:

{
  "due_date": "2022-08-16T15:57:31.325116Z"
}

{{ strptime(due_date, "%Y-%m-%dT%H:%M:%S.%fZ") }}

strftime

Formats a datetime object into a string.

Syntax:

{{ strftime(datetime_object, format) }}

The most common pattern is parsing and reformatting in one step:

{{ strftime(strptime(due_date, "%Y-%m-%dT%H:%M:%S.%fZ"), "%d/%m/%y") }}

Output: 16/08/22

See Python's strftime reference for the full list of format codes.

epoch_to_datetime

Converts a Unix epoch timestamp into a datetime object.

Syntax:

{{ epoch_to_datetime(epoch_time, timezone_hour) }}

Parameters:

Parameter	Description	Default
epoch_time	Unix timestamp (seconds since January 1, 1970 UTC)	—
timezone_hour	Timezone offset in hours (e.g. 8 for UTC+8, -5 for UTC-5)	0

Example:

{
  "created_at": 1665494864
}

{{ strftime(epoch_to_datetime(created_at, 8), "%y-%m-%d") }}

Output: 22-10-11

Format currency / numbers

Use Python's string formatting to display numbers as currency or formatted values.

Syntax:

{{ "${:,.2f}".format(value) }}

Example:

{
  "gross_total": 2000.50
}

{{ "${:,.2f}".format(gross_total) }}

Output: $2,000.50

More formatting patterns:

{{ "{:,.2f}".format(amount) }}        <!-- 1,234.56 -->
{{ "${:,.0f}".format(amount) }}       <!-- $1,235 -->
{{ "{:.2f}%".format(percentage) }}    <!-- 15.50% -->

Comparison functions

APITemplate.io also provides comparison functions as an alternative to standard operators:

Function	Description	Example
gt	Greater than	gt(val1, val2)
gte	Greater than or equal to	gte(val1, val2)
lt	Less than	lt(val1, val2)
lte	Less than or equal to	lte(val1, val2)

Example:

{% if gt(life_span, 160) and lt(life_span, 180) %}
    {{ product }} is expiring soon!
{% elif gte(life_span, 180) %}
    {{ product }} has expired!
{% endif %}

Next steps

• Default Filters — standard Jinja2 filters
• Examples — practical template patterns