Custom format templating

Custom format templating extension allows users to create custom files in almost any shape or form. It works by defining a custom template and later calling it on export with the annotation data.

Installation

Custom format templating extension is provided and maintained by Rossum.ai in the form of webhook. To start using it, follow these steps:

Login to your Rossum account.
Navigate to Extensions → My extensions.
Click on Create extension.
Fill the following fields:
1. Name: Custom format templating
2. Trigger events: Export
3. Extension type: Webhook
4. URL (see below)
In "Advanced settings" select Token owner (should have Admin access)
In the "Additional notification metadata" enable Schemas
Click Create the webhook.

Environment	Webhook URL
EU1 Ireland	https://elis.custom-format-templating.rossum-ext.app/
EU2 Frankfurt	https://shared-eu2.custom-format-templating.rossum-ext.app/
US east coast	https://us.custom-format-templating.rossum-ext.app/
Japan Tokyo	https://shared-jp.custom-format-templating.rossum-ext.app/

Basic usage

Work in progress

We're still working on this part and would love to hear your thoughts! Feel free to share your feedback or submit a pull request. Thank you! 🙏

Tracking issue: https://github.com/rossumai/university/issues/382

Available configuration options

{
  "export_configs": [
    {
      // Optional. Specifies resulting file content encoding. Default: "utf-8".
      "content_encoding": "utf-8",

      // Name of the export template used for later reference in the export pipeline.
      "export_reference_key": "example_invoice_template",

      // In-line template of the file to be exported. You can either use this in-line version or
      // use `file_content_template_multiline` for multiple lines instead.
      "file_content_template": "…",

      // Multiline template of the file to be exported. You can either use this multipline version
      // or use `file_content_template` for in-line templates instead.
      "file_content_template_multiline": [
        // Rows of the template. Each row is a new line (no need for "\n" separators).
        "…",
        "…"
      ]
    }
    // …
  ]
}

In the template definitions (file_content_template or file_content_template_multiline) you can reference any field from annotation object by using dot syntax (for example {{field.document_id}}).

It is also possible to access the annotation payload like so: {{payload['document']['original_file_name']}}. This way, you can create a link to the annotation directly in the template, for example: https://example.rossum.app/document/{{payload['annotation']['id']}}

warning

Maximum five export configs can be defined per annotation export.

Obtaining generated files

Outputs from the Custom format templating webhook are not available anywhere in the UI. Instead, they are stored as a "document relation". To get the actual document content, you need to call two API endpoints. First, you need to get the relevant relation:

curl 'https://elis.rossum.ai/api/v1/document_relations?type=export&annotation=1234567&key=export_annotation_to_csv' \
--header 'Authorization: Bearer XYZ'

You can omit the key to get all available relations for given annotation. The response will look something like this:

{
  "pagination": { "total": 1, "total_pages": 1, "next": null, "previous": null },
  "results": [
    {
      "id": 1234567,
      "type": "export",
      "key": "export_annotation_to_csv",
      "annotation": "https://elis.rossum.ai/api/v1/annotations/1234567",
      "documents": ["https://elis.rossum.ai/api/v1/documents/1234567"],
      "url": "https://elis.rossum.ai/api/v1/document_relations/1234567"
    }
  ]
}

To get the actual generated document content, you need to call the following API endpoint (see the highlighted document URL above):

curl 'https://elis.rossum.ai/api/v1/documents/1234567/content' \
--header 'Authorization: Bearer XYZ'

Note that you do not need to know these technical details. This extension is typically to be used in combination with REST API Export extension which knows how to work with it.

Configuration examples

Original document (base64)

{
  "export_configs": [
    {
      "export_reference_key": "export_original_file",
      "file_content_template": "{{file.original_file|b64encode}}"
    }
  ]
}

Custom CSV

Define CSV header fields as well as the actual datapoints to be exported:

{
  "export_configs": [
    {
      "export_reference_key": "export_annotation_to_csv",
      "file_content_template": "Document ID,Document Type,Quantity\n{{field.document_id}},{{field.document_type}},{{field.line_items[0].item_quantity}}"
    }
  ]
}

Alternatively, it is possible to leverage file_content_template_multiline for better readability:

{
  "export_configs": [
    {
      "export_reference_key": "export_annotation_to_csv",
      "file_content_template_multiline": [
        "Document ID,Document Type,Quantity",
        "{{field.document_id}},{{field.document_type}},{{field.line_items[0].item_quantity}}"
      ],
      "content_encoding": "utf-8"
    }
  ]
}

Both of the configurations should generate something like this:

Document ID,Document Type,Quantity
123456,tax_invoice,750

It is also possible to iterate line items:

{
  "export_configs": [
    {
      "export_reference_key": "export_annotation_to_csv",
      "file_content_template_multiline": [
        "Document ID,Document Type,Item Description,Item Quantity",
        "{% for item in field.line_items %}{{field.document_id}},{{field.document_type}},{{item.item_description}},{{item.item_quantity}}\n{% endfor %}"
      ],
      "content_encoding": "utf-8"
    }
  ]
}

The generated CSV would now contain all the line items, for example:

Document ID,Document Type,Item Description,Item Quantity
123456,tax_invoice,AWS services #1,750
123456,tax_invoice,AWS services #2,750
123456,tax_invoice,AWS services #3,750

Learn how to get the generated file in Obtaining generated files section.

Custom XML

Similarly to other formats, custom XML can be defined using the following template (notice the |upper and |default filters):

{
  "export_configs": [
    {
      "export_reference_key": "export_annotation_to_xml",
      "content_encoding": "utf-8",
      "file_content_template_multiline": [
        "<ROSSUM>",
        "  <INVOICE>",
        "    <HEADER>",
        "      <DOCUMENT_ID>{{ field.document_id }}</DOCUMENT_ID>",
        "      <DOCUMENT_TYPE>{{ field.document_type }}</DOCUMENT_TYPE>",
        "      <DOCUMENT_LANGUAGE>{{ field.language }}</DOCUMENT_LANGUAGE>",
        "      <DATE_ISSUE>{{ field.date_issue }}</DATE_ISSUE>",
        "      <DATE_DUE>{{ field.date_due }}</DATE_DUE>",
        "      <CURRENCY>{{ field.currency | upper }}</CURRENCY>",
        "      <AMOUNT_TOTAL>{{ field.amount_total }}</AMOUNT_TOTAL>",
        "      <AMOUNT_TOTAL_TAX>{{ field.amount_total_tax | default(0,true) }}</AMOUNT_TOTAL_TAX>",
        "    </HEADER>",
        "  </INVOICE>",
        "</ROSSUM>"
      ]
    }
  ]
}

tip

If the fields may include any of the following chars (>, <, &, or ") you SHOULD escape it unless the variable contains well-formed and trusted HTML/XML like so: { field.name|e }

You can learn more about this (and other) filter(s) here: https://jinja.palletsprojects.com/en/stable/templates/#working-with-manual-escaping

Custom JSON

Creates custom JSON templates with some header fields and line items (iteration over the line items is highlighted).

{
  "export_configs": [
    {
      "export_reference_key": "export_annotation_to_json",
      "content_encoding": "utf-8",
      "file_content_template_multiline": [
        "{",
        "  \"document_id\": \"{{ field.document_id }}\",",
        "  \"document_type\": \"{{ field.document_type }}\",",
        "  \"line_items\": [",
        "    {% for item in field.line_items %}{",
        "      \"code\": \"{{ item.item_code }}\",",
        "      \"description\": \"{{ item.item_description }}\",",
        "      \"quantity\": {{ item.item_quantity }},",
        "      \"amount\": {{ item.item_amount }},",
        "    }{% if not loop.last %},{% endif %}",
        "  {% endfor %}]",
        "}"
      ]
    }
  ]
}

Custom TXT (The Tree)

This is example of the Jinja2 language capabilities. The following example is a small Jinja program that generates simple ASCII art representation of a tree. The tree height is a parameter which can be changed, see line 15 in the example config.

{
  "export_configs": [
    {
      "export_reference_key": "export_tree_ascii_art",
      "content_encoding": "utf-8",
      "file_content_template_multiline": [
        "{%- macro draw_tree(height) -%}",
        "{%- set width = height * 2 - 1 %}",
        "{%- for level in range(1, height + 1) -%}",
        "{%- set padding = (width - (level * 2 - 1)) // 2 %}",
        "{{ ' ' * padding }}{{ '*' * (level * 2 - 1) }}{{ ' ' * padding }}",
        "{%- endfor %}",
        "{{ ' ' * ((width - 1) // 2) }}|{{ ' ' * ((width - 1) // 2) }}",
        "{%- endmacro %}",
        "{{ draw_tree(5) }}",
        ""
      ]
    }
  ]
}

Result is a generated TXT file representing a tree with crown height of 5 rows:

    *
   ***
  *****
 *******
*********
    |

Installation​

Basic usage​

Available configuration options​

Obtaining generated files​

Configuration examples​

Original document (base64)​

Custom CSV​

Custom XML​

Custom JSON​

Custom TXT (The Tree)​