29 KiB
| title |
|---|
| Helper Functions |
Some common functions are provided for use in custom report and label templates. To include these, load the report functions at the start of the template:
{% raw %}
<!-- Load the report helper functions -->
{% load report %}
{% endraw %}
!!! tip "Use the Source, Luke"
To see the full range of available helper functions, refer to the source file [report.py]({{ sourcefile("src/backend/InvenTree/report/templatetags/report.py") }}) where these functions are defined!
Assigning Variables
When making use of helper functions within a template, it can be useful to store the result of the function to a variable, rather than immediately rendering the output.
For example, using the render_currency helper function, we can store the output to a variable which can be used at a later point in the template:
{% raw %}
{% load report %}
{% render_currency 12.3 currency='USD' as myvar %}
...
...
Result: {{ myvar }}
{% endraw %}
Note the use of the as keyword to assign the output of the function to a variable. This can be used to assign the result of a function to a named variable, which can then be used later in the template.
Data Structure Access
A number of helper functions are available for accessing data contained in a particular structure format:
Index Access
To return the element at a given index in a container which supports indexed access (such as a list), use the getindex function:
::: report.templatetags.report.getindex
options:
show_docstring_description: false
show_source: False
Example
{% raw %}
{% getindex my_list 1 as value %}
Item: {{ value }}
{% endraw %}
Key Access
To return an element corresponding to a certain key in a container which supports key access (such as a dictionary), use the getkey function:
::: report.templatetags.report.getkey
options:
show_docstring_description: false
show_source: False
Example
{% raw %}
<ul>
{% for key in keys %}
{% getkey my_container key as value %}
<li>{{ key }} = {{ value }}</li>
{% endfor %}
</ul>
{% endraw %}
Database Helpers
A number of helper functions are available for accessing database objects:
order_queryset
The order_queryset function allows for ordering of a provided queryset. It takes a queryset and a list of ordering arguments, and returns an ordered queryset.
::: report.templatetags.report.order_queryset
options:
show_docstring_description: false
show_source: False
!!! info "Provided QuerySet"
The provided queryset must be a valid Django queryset object, which is already available in the template context.
Example
In a report template which has a PurchaseOrder object available in its context as the variable order, return the matching line items ordered by part name:
{% raw %}
{% load report %}
{% order_queryset order.lines.all 'part__name' as ordered_lines %}
filter_queryset
The filter_queryset function allows for arbitrary filtering of the provided queryset. It takes a queryset and a list of filter arguments, and returns a filtered queryset.
::: report.templatetags.report.filter_queryset
options:
show_docstring_description: false
show_source: False
!!! info "Provided QuerySet"
The provided queryset must be a valid Django queryset object, which is already available in the template context.
!!! warning "Advanced Users"
The filter_queryset function is a powerful tool, but it is also easy to misuse. It assumes that the user has a good understanding of Django querysets and the underlying database structure.
Example
In a report template which has a PurchaseOrder object available in its context, fetch any line items which have a received quantity greater than zero:
{% raw %}
{% load report %}
{% filter_queryset order.lines.all received__gt=0 as received_lines %}
<ul>
{% for line in received_lines %}
<li>{{ line.part.part.full_name }} - {{ line.received }} / {{ line.quantity }}</li>
{% endfor %}
</ul>
{% endraw %}
filter_db_model
The filter_db_model function allows for filtering of a database model based on a set of filter arguments. It takes a model class and a list of filter arguments, and returns a filtered queryset.
::: report.templatetags.report.filter_db_model
options:
show_docstring_description: false
show_source: False
Example
Generate a list of all active customers:
{% raw %}
{% load report %}
{% filter_db_model 'company.company' is_customer=True active=True as active_customers %}
<ul>
{% for customer in active_customers %}
<li>{{ customer.name }}</li>
{% endfor %}
</ul>
{% endraw %}
Advanced Database Queries
More advanced database filtering should be achieved using a report plugin, and adding custom context data to the report template.
List Helpers
The following helper functions are available for working with list (or list-like) data structures:
length
Return the length of a list (or list-like) data structure. Note that this will also work for other data structures which support the len() function, such as strings, dictionaries or querysets:
::: report.templatetags.report.length
options:
show_docstring_description: false
show_source: False
first
Return the first element of a list (or list-like) data structure:
::: report.templatetags.report.first
options:
show_docstring_description: false
show_source: False
last
Return the last element of a list (or list-like) data structure:
::: report.templatetags.report.last
options:
show_docstring_description: false
show_source: False
reverse
Return a list (or list-like) data structure in reverse order:
::: report.templatetags.report.reverse
options:
show_docstring_description: false
show_source: False
truncate
Return a truncated version of a list (or list-like) data structure, containing only the first N elements:
::: report.templatetags.report.truncate
options:
show_docstring_description: false
show_source: False
String Formatting
strip
Return a string with leading and trailing whitespace removed:
::: report.templatetags.report.strip
options:
show_docstring_description: false
show_source: False
lstrip
Return a string with leading whitespace removed:
::: report.templatetags.report.lstrip
options:
show_docstring_description: false
show_source: False
rstrip
Return a string with trailing whitespace removed:
::: report.templatetags.report.rstrip
options:
show_docstring_description: false
show_source: False
split
Return a list of substrings by splitting a string based on a specified separator:
::: report.templatetags.report.split
options:
show_docstring_description: false
show_source: False
join
Return a string by joining a list of strings into a single string, using a specified separator:
::: report.templatetags.report.join
options:
show_docstring_description: false
show_source: False
replace
Return a string where occurrences of a specified substring are replaced with another substring:
::: report.templatetags.report.replace
options:
show_docstring_description: false
show_source: False
lowercase
Return a string with all characters converted to lowercase:
::: report.templatetags.report.lowercase
options:
show_docstring_description: false
show_source: False
uppercase
Return a string with all characters converted to uppercase:
::: report.templatetags.report.uppercase
options:
show_docstring_description: false
show_source: False
titlecase
Return a string with the first character of each word converted to uppercase and the remaining characters converted to lowercase:
::: report.templatetags.report.titlecase
options:
show_docstring_description: false
show_source: False
Number Formatting
A number of helper functions are available for formatting numbers in a particular way. These can be used to format numbers according to a particular number of decimal places, or to add leading zeros, for example.
format_number
The helper function format_number allows for some common number formatting options. It takes a number (or a number-like string) as an input, as well as some formatting arguments. It returns a string containing the formatted number:
::: report.templatetags.report.format_number
options:
show_docstring_description: false
show_source: False
Examples
{% raw %}
{% load report %}
<!-- Basic usage: strip trailing zeros -->
{% format_number 3.14159265359 decimal_places=5 %}
<!-- output: 3.14159 -->
<!-- Leading zeros with 'leading' option -->
{% format_number 3.14159265359 decimal_places=5 leading=3 %}
<!-- output: 003.14159 -->
<!-- Round to integer -->
{% format_number 3.14159265359 integer=True %}
<!-- output: 3 -->
<!-- Thousands separator -->
{% format_number 9988776.5 decimal_places=2 separator=True %}
<!-- output: 9,988,776.50 -->
<!-- Locale-aware formatting: decimal comma, dot thousands separator -->
{% format_number 9988776.5 decimal_places=2 separator=True locale='de-de' %}
<!-- output: 9.988.776,50 -->
<!-- Scale a value with a multiplier before formatting -->
{% format_number 0.175 multiplier=100 decimal_places=1 %}
<!-- output: 17.5 -->
<!-- Allow up to N significant decimal places, but suppress trailing zeros -->
{% format_number 1234.5 decimal_places=2 max_decimal_places=6 %}
<!-- output: 1234.5 -->
{% endraw %}
Custom Format Strings
The fmt argument accepts a Unicode number pattern string (the same syntax used by Babel). When fmt is provided it takes complete priority over the decimal_places, max_decimal_places, leading, and separator arguments — those arguments are silently ignored.
The integer and multiplier arguments are still applied to the number before the format string is used.
| Symbol | Meaning |
|---|---|
0 |
Required digit — always rendered, even if zero |
# |
Optional digit — suppressed when not significant |
, |
Grouping separator (position defines group size) |
. |
Decimal separator |
Common patterns:
| Pattern | Example output |
|---|---|
0 |
1235 |
#,##0 |
1,235 |
0.00 |
1234.57 |
#,##0.00 |
1,234.57 |
000 |
007 |
{% raw %}
{% load report %}
<!-- Two decimal places, no grouping -->
{% format_number 1234.5678 fmt='0.00' %}
<!-- output: 1234.57 -->
<!-- Two decimal places with thousands separator -->
{% format_number 1234.5678 fmt='#,##0.00' %}
<!-- output: 1,234.57 -->
<!-- Same pattern, German locale: dot thousands, comma decimal -->
{% format_number 1234.5678 fmt='#,##0.00' locale='de-de' %}
<!-- output: 1.234,57 -->
<!-- Integer with thousands separator, large number -->
{% format_number 9988776655.4321 fmt='#,##0' integer=True %}
<!-- output: 9,988,776,655 -->
{% endraw %}
Date Formatting
For rendering date and datetime information, the following helper functions are available:
Both functions resolve their output using the following priority order:
fmt=argument — a strftime format string. When provided, this takes full priority;localeanddate_formatare ignored.locale=argument — when nofmtis given, Babel formats the value using the style set bydate_format(defaultmedium).- Server
LANGUAGE_CODE— used as the locale when nolocale=argument is supplied.
Date Format Styles
The date_format argument controls how Babel renders the date when locale-aware formatting is used. The four named styles are:
| Style | format_date example (en-us, 2025-01-12) |
format_datetime example (en-us, 2025-01-12 14:30) |
|---|---|---|
full |
Sunday, January 12, 2025 |
Sunday, January 12, 2025 at 2:30:00 PM UTC |
long |
January 12, 2025 |
January 12, 2025 at 2:30:00 PM UTC |
medium (default) |
Jan 12, 2025 |
Jan 12, 2025, 2:30:00 PM |
short |
1/12/25 |
1/12/25, 2:30 PM |
The exact output varies by locale — the table above uses en-us.
format_date
::: report.templatetags.report.format_date
options:
show_docstring_description: false
show_source: False
Examples
{% raw %}
{% load report %}
<!-- Default: medium style, locale from LANGUAGE_CODE -->
{% format_date my_date %}
<!-- output (en-us): Jan 12, 2025 -->
<!-- Explicit strftime format string — locale and date_format are ignored -->
{% format_date my_date fmt="%d/%m/%Y" %}
<!-- output: 12/01/2025 -->
<!-- Locale-aware, default medium style -->
{% format_date my_date locale='en-us' %}
<!-- output: Jan 12, 2025 -->
<!-- Short style -->
{% format_date my_date locale='en-us' date_format='short' %}
<!-- output: 1/12/25 -->
<!-- Full style -->
{% format_date my_date locale='en-us' date_format='full' %}
<!-- output: Sunday, January 12, 2025 -->
{% endraw %}
format_datetime
::: report.templatetags.report.format_datetime
options:
show_docstring_description: false
show_source: False
Examples
{% raw %}
{% load report %}
<!-- Default: medium style, locale from LANGUAGE_CODE -->
{% format_datetime my_datetime %}
<!-- output (en-us): Jan 12, 2025, 2:30:00 PM -->
<!-- Explicit strftime format — locale and date_format are ignored -->
{% format_datetime my_datetime fmt="%d-%m-%Y %H:%M" %}
<!-- output: 12-01-2025 14:30 -->
<!-- Locale-aware, default medium style -->
{% format_datetime my_datetime locale='en-us' %}
<!-- output: Jan 12, 2025, 2:30:00 PM -->
<!-- Short style -->
{% format_datetime my_datetime locale='de-de' date_format='short' %}
<!-- output: 12.01.25, 14:30 -->
<!-- Convert to a specific timezone before formatting -->
{% format_datetime my_datetime timezone="Australia/Sydney" locale='en-au' %}
{% endraw %}
Currency Formatting
render_currency
The helper function render_currency allows for simple rendering of currency data. This function can also convert the specified amount of currency into a different target currency:
::: report.templatetags.report.render_currency
options:
show_docstring_description: false
show_source: False
Decimal Places
When no decimal place arguments are provided, the locale/currency standard is used (e.g. 2 places for USD, 0 for JPY).
decimal_places and max_decimal_places work the same way as in format_number:
| Argument | Effect |
|---|---|
decimal_places=N |
Forces exactly N decimal digits (zero-padded) |
max_decimal_places=M |
Allows up to M decimal digits, suppressing trailing zeros beyond decimal_places |
| Both set | Forced minimum of decimal_places, optional up to max_decimal_places |
| Neither set | Locale/currency default (e.g. 2 for USD) |
{% raw %}
{% load report %}
<!-- locale default for USD: 2 decimal places -->
{% render_currency order.total_price currency='USD' %}
<!-- output: $1,234.56 -->
<!-- force 3 decimal places -->
{% render_currency order.total_price currency='USD' decimal_places=3 %}
<!-- output: $1,234.560 -->
<!-- at least 2, up to 4 — trailing zeros beyond the value are suppressed -->
{% render_currency order.total_price currency='USD' decimal_places=2 max_decimal_places=4 %}
<!-- output: $1,234.5600 or $1,234.56 depending on the value -->
{% endraw %}
Locale and Symbol Rendering
The locale controls how the currency symbol and separators are rendered. For example, USD 1234.56 with various locales:
| Locale | Output |
|---|---|
en-us |
$1,234.56 |
en-gb |
US$1,234.56 |
en-au |
USD1,234.56 |
de-de |
1.234,56 $ |
The locale is resolved in the following priority order:
- Explicit
locale=argument — highest priority, always wins - Server
LANGUAGE_CODE— fallback
Leading Digits
The leading argument specifies the minimum number of digits to render before the decimal point (zero-padded). This works identically to leading in format_number:
{% raw %}
{% load report %}
<!-- default: no padding -->
{% render_currency order.total_price currency='USD' %}
<!-- output: $1.23 -->
<!-- force at least 4 integer digits -->
{% render_currency order.total_price currency='USD' leading=4 %}
<!-- output: $0,001.23 -->
{% endraw %}
Custom Format Strings
The fmt argument accepts a Unicode number pattern string (same syntax as format_number). When fmt is provided, it takes complete priority over decimal_places, max_decimal_places, and leading — those arguments are ignored.
The locale, currency, multiplier, and include_symbol arguments are still applied when fmt is set.
To include the currency symbol in a fmt pattern, use the ¤ placeholder. Without it, no symbol appears regardless of include_symbol.
| Pattern | Example output (en-us, USD) |
|---|---|
#,##0.00 |
1,234.56 (no symbol) |
¤#,##0.00 |
$1,234.56 |
¤#,##0.0000 |
$1,234.5600 |
¤ #,##0.00 |
$ 1,234.56 |
{% raw %}
{% load report %}
<!-- No symbol (no ¤ in pattern) -->
{% render_currency order.total_price currency='USD' fmt='#,##0.00' %}
<!-- output: 1,234.56 -->
<!-- Symbol via ¤ placeholder -->
{% render_currency order.total_price currency='USD' fmt='¤#,##0.0000' locale='en-us' %}
<!-- output: $1,234.5600 -->
<!-- fmt + locale: de-de separators -->
{% render_currency order.total_price currency='USD' fmt='#,##0.00' locale='de-de' %}
<!-- output: 1.234,56 -->
<!-- fmt takes priority — decimal_places=2 is ignored -->
{% render_currency order.total_price currency='USD' fmt='0.0000' decimal_places=2 %}
<!-- output: 1234.5600 -->
{% endraw %}
Example
{% raw %}
{% load report %}
<em>Line Item Unit Pricing:</em>
<ul>
{% for line in order.lines %}
<li>{% render_currency line.price currency=order.supplier.currency %}</li>
{% endfor %}
</ul>
<!-- Force 2 decimal places, convert to NZD -->
Total Price: {% render_currency order.total_price currency='NZD' decimal_places=2 %}
<!-- US-style symbol, regardless of server locale -->
Total Price: {% render_currency order.total_price currency='USD' locale='en-us' %}
{% endraw %}
convert_currency
To convert a currency value from one currency to another, use the convert_currency helper function:
::: report.templatetags.report.convert_currency
options:
show_docstring_description: false
show_source: False
!!! info "Data Types"
The money parameter must be Money class instance. If not, an error will be raised.
create_currency
Create a currency instance using the create_currency helper function. This returns a Money class instance based on the provided amount and currency type.
::: report.templatetags.report.create_currency
options:
show_docstring_description: false
show_source: False
Maths Operations
Simple mathematical operators are available, as demonstrated in the example template below. These operators can be used to perform basic arithmetic operations within the report template.
!!! info "Input Types"
These mathematical functions accept inputs of various input types, and attempt to perform the operation accordingly. Note that any inputs which are provided as strings or numbers will be converted to Decimal class types before the operation is performed.
add
Add two numbers together using the add helper function:
::: report.templatetags.report.add
options:
show_docstring_description: false
show_source: False
subtract
Subtract one number from another using the subtract helper function:
::: report.templatetags.report.subtract
options:
show_docstring_description: false
show_source: False
multiply
Multiply two numbers together using the multiply helper function:
::: report.templatetags.report.multiply
options:
show_docstring_description: false
show_source: False
divide
Divide one number by another using the divide helper function:
::: report.templatetags.report.divide
options:
show_docstring_description: false
show_source: False
modulo
Perform a modulo operation using the modulo helper function:
::: report.templatetags.report.modulo
options:
show_docstring_description: false
show_source: False
Example
{% raw %}
<!-- Load the report helper functions -->
{% load report %}
{% add 1 3 %} <!-- Add two numbers together -->
{% subtract 4 3 %} <!-- Subtract 3 from 4 -->
{% multiply 1.2 3.4 %} <!-- Multiply two numbers -->
<!-- Perform a calculation and store the result -->
{% divide 10 2 as division_result %} <!-- Divide 10 by 2 -->
Division Result: {{ division_result }}
{% endraw %}
These operators can also be used with variables:
{% raw %}
{% load report %}
{% for line in order.lines %}
Total: {% multiply line.purchase_price line.quantity %}<br>
{% endfor %}
{% endraw %}
Media Files
Media files are any files uploaded to the InvenTree server by the user. These are stored under the /media/ directory and can be accessed for use in custom reports or labels.
uploaded_image
You can access an uploaded image file if you know the path of the image, relative to the top-level /media/ directory. To load the image into a report, use the {% raw %}{% uploaded_image ... %}{% endraw %} tag:
::: report.templatetags.report.uploaded_image
options:
show_docstring_description: false
show_source: False
{% raw %}
<!-- Load the report helper functions -->
{% load report %}
<img src='{% uploaded_image "subdir/my_image.png" width=480 rotate=45 %}'/>
{% endraw %}
!!! info "Missing Image"
If the supplied image filename does not exist, it will be replaced with a placeholder image file
!!! warning "Invalid Image"
If the supplied file is not a valid image, it will be replaced with a placeholder image file
Image Manipulation
The {% raw %}{% uploaded_image %}{% endraw %} tag supports some optional parameters for image manipulation. These can be used to adjust or resize the image - to reduce the size of the generated report file, for example.
{% raw %}
{% load report %}
<img src='{% uploaded_image "image_file.png" width=500 rotate=45 %}'>
{% endraw %}```
### encode_svg_image
::: report.templatetags.report.encode_svg_image
options:
show_docstring_description: false
show_source: False
SVG images need to be handled in a slightly different manner. When embedding an uploaded SVG image, use the `{% raw %}{% encode_svg_image ... %}{% endraw %}` tag:
```html
{% raw %}
<!-- Load the report helper functions -->
{% load report %}
<img src='{% encode_svg_image svg_image_file %}'/>
{% endraw %}
part_image
A shortcut function is provided for rendering an image associated with a Part instance. You can render the image of the part using the {% raw %}{% part_image ... %}{% endraw %} template tag:
::: report.templatetags.report.part_image
options:
show_docstring_description: false
show_source: False
{% raw %}
<!-- Load the report helper functions -->
{% load report %}
<img src='{% part_image part %}'/>
{% endraw %}
Image Arguments
Any optional arguments which can be used in the uploaded_image tag can be used here too.
Image Variations
The Part model supports preview (256 x 256) and thumbnail (128 x 128) versions of the uploaded image. These variations can be used in the generated reports (e.g. to reduce generated file size):
{% raw %}
{% load report %}
<!-- Render the "preview" image variation -->
<img src='{% part_image part preview=True %}'>
<!-- Render the "thumbnail" image variation -->
<img src='{% part_image part thumbnail=True %}'>
{% endraw %}
company_image
A shortcut function is provided for rendering an image associated with a Company instance. You can render the image of the company using the {% raw %}{% company_image ... %}{% endraw %} template tag:
::: report.templatetags.report.company_image
options:
show_docstring_description: false
show_source: False
{% raw %}
<!-- Load the report helper functions -->
{% load report %}
<img src='{% company_image company %}'/>
{% endraw %}
Image Variations
Preview and thumbnail image variations can be rendered for the company_image tag, in a similar manner to part image variations
Icons
Some models (e.g. part categories and locations) allow to specify a custom icon. To render these icons in a report, there is a {% raw %}{% icon location.icon %}{% endraw %} template tag from the report template library available.
This tag renders the required html for the icon.
!!! info "Loading fonts"
Additionally the icon fonts need to be loaded into the template. This can be done using the {% raw %}{% include_icon_fonts %}{% endraw %} template tag inside of a style block
!!! tip "Custom classes for styling the icon further"
The icon template tag accepts an optional class argument which can be used to apply a custom class to the rendered icon used to style the icon further e.g. positioning it, changing it's size, ... {% raw %}{% icon location.icon class="my-class" %}{% endraw %}.
{% raw %}
{% load report %}
{% block style %}
{% include_icon_fonts %}
{% endblock style %}
{% icon location.icon %}
{% endraw %}
InvenTree Logo
A template tag is provided to load the InvenTree logo image into a report. You can render the logo using the {% raw %}{% logo_image %}{% endraw %} tag:
{% raw %}
{% load report %}
<img src='{% logo_image %}'/>
{% endraw %}
Custom Logo
If the system administrator has enabled a custom logo then this logo will be used instead of the base InvenTree logo.
This is a useful way to get a custom company logo into your reports.
If you have a custom logo, but explicitly wish to load the InvenTree logo itself, add custom=False to the tag:
{% raw %}
{% load report %}
<img src='{% logo_image custom=False %}'/>
{% endraw %}
Report Assets
Report Assets are files specifically uploaded by the user for inclusion in generated reports and labels.
You can add asset images to the reports and labels by using the {% raw %}{% asset ... %}{% endraw %} template tag:
{% raw %}
<!-- Load the report helper functions -->
{% load report %}
<img src="{% asset 'my_awesome_logo.png' %}"/>
{% endraw %}
Parameters
If you need to reference a parameter for a particular model instance, within the context of your template, you can use the parameter template tag:
parameter
This returns a Parameter object which contains the value of the parameter, as well as any associated metadata (e.g. units, description, etc).
::: report.templatetags.report.parameter
options:
show_docstring_description: false
show_source: False
Example
The following example assumes that you have a report or label which contains a valid Part instance:
{% raw %}
{% load report %}
{% parameter part "length" as length %}
Part: {{ part.name }}<br>
Length: {{ length.data }} [{{ length.units }}]
{% endraw %}
A Parameter has the following available attributes:
| Attribute | Description |
|---|---|
| Name | The name of the parameter (e.g. "Length") |
| Description | The description of the parameter |
| Data | The value of the parameter (e.g. "123.4") |
| Units | The units of the parameter (e.g. "km") |
| Template | A reference to a ParameterTemplate |
parameter_value
To access just the value of a parameter, use the parameter_value template tag:
::: report.templatetags.report.parameter_value
options:
show_docstring_description: false
show_source: False
Example
{% raw %}
{% load report %}
{% parameter_value part "length" backup_value="3"as length_value %}
Part: {{ part.name }}<br>
Length: {{ length_value }}
{% endraw %}
Rendering Markdown
Some data fields (such as the Notes field available on many internal database models) support markdown formatting. To render markdown content in a custom report, there are template filters made available through the django-markdownify library. This library provides functionality for converting markdown content to HTML representation, allowing it to be then rendered to PDF by the InvenTree report generation pipeline.
To render markdown content in a report, consider the following simplified example:
{% raw %}
{% load markdownify %}
<h3>Part Notes</h3>
<p>
{{ part.notes | markdownify }}
</p>
{% endraw %}
You can read further details in the django-markdownify documentation.
List of tags and filters
The following tags and filters are available.
{{ tags_and_filters() }}