debian/control

@@ -13,7 +13,9 @@ Homepage: https://dev.entrouvert.org/projects/passerelle
 
 Package: python3-passerelle
 Architecture: all
-Depends: pdftk,
+Depends: ghostscript,
+         pdftk,
+         poppler-utils,
          python3-cmislib,
          python3-dateutil,
          python3-distutils,

debian/debian_config.py

@@ -36,6 +36,11 @@ LOGGING['loggers']['paramiko.transport'] = {
     'propagate': True,
 }
 
+# silence pdfrw
+LOGGING['loggers']['pdfrw'] = {
+    'propagate': False,
+}
+
 exec(open('/etc/%s/settings.py' % PROJECT_NAME).read())
 
 # run additional settings snippets

passerelle/apps/pdf/forms.py

@@ -0,0 +1,63 @@
+# passerelle - uniform access to multiple data sources and services
+# Copyright (C) 2020 Entr'ouvert
+#
+# This program is free software: you can redistribute it and/or modify it
+# under the terms of the GNU Affero General Public License as published
+# by the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from django import forms
+from django.utils.translation import gettext_lazy as _
+
+from passerelle.utils.forms import ConditionField, TemplateField
+from passerelle.utils.pdf import PDF
+
+from . import models
+
+
+class FieldsMappingEditForm(forms.ModelForm):
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        if not self.instance.fill_form_file:
+            return
+        fields_mapping = self.instance.fields_mapping or {}
+        with self.instance.fill_form_file as fd:
+            pdf = PDF(fd)
+        for page in pdf.pages:
+            for i, field in enumerate(page.fields):
+                name = f'field_{field.digest_id}'
+                if field.widget_type == 'checkbox':
+                    help_text = _('boolean expression')
+                    field_class = ConditionField
+                elif field.widget_type == 'text':
+                    help_text = _('text template')
+                    field_class = TemplateField
+                else:
+                    continue
+                label = _('field {number} ({help_text})').format(number=i + 1, help_text=help_text)
+                initial = fields_mapping.get(name, '')
+                self.fields[name] = field_class(label=label, required=False, initial=initial)
+                self.fields[name].page_number = page.page_number
+                self.fields[name].widget.attrs['tabindex'] = '0'
+                self.fields[name].widget.attrs['class'] = '0'
+
+    def save(self, commit=True):
+        fields_mapping = {}
+        for name in self.fields:
+            value = self.cleaned_data.get(name)
+            if value:
+                fields_mapping[name] = value
+        self.instance.fields_mapping = fields_mapping
+        return super().save(commit=commit)
+
+    class Meta:
+        model = models.Resource
+        fields = ()

passerelle/apps/pdf/migrations/0002_resource_fill_form_file.py

@@ -18,11 +18,11 @@ class Migration(migrations.Migration):
             name='fill_form_file',
             field=models.FileField(
                 blank=True,
-                help_text='PDF file, used if not input-form in fill-form payload',
+                help_text='PDF file',
                 null=True,
                 upload_to=passerelle.utils.models.resource_file_upload_to,
                 validators=[passerelle.apps.pdf.models.validate_pdf],
-                verbose_name='Fill Form default input file',
+                verbose_name='Fill Form input file',
             ),
         ),
     ]

passerelle/apps/pdf/migrations/0003_resource_fields_mapping.py

@@ -0,0 +1,19 @@
+# Generated by Django 3.2.18 on 2023-03-01 16:48
+
+from django.contrib.postgres.fields.jsonb import JSONField
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('pdf', '0002_resource_fill_form_file'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='resource',
+            name='fields_mapping',
+            field=JSONField(null=True, verbose_name='Field mapping', blank=True),
+        ),
+    ]

passerelle/apps/pdf/models.py

@@ -18,10 +18,10 @@ import base64
 import os
 import subprocess
 import tempfile
-import xml.etree.ElementTree as ET
 from collections import OrderedDict
 
 from django.conf import settings
+from django.contrib.postgres.fields.jsonb import JSONField
 from django.core.exceptions import ValidationError
 from django.db import models
 from django.http.response import HttpResponse
@@ -31,6 +31,8 @@ from passerelle.base.models import BaseResource
 from passerelle.utils.api import endpoint
 from passerelle.utils.jsonresponse import APIError
 from passerelle.utils.models import resource_file_upload_to
+from passerelle.utils.pdf import PDF
+from passerelle.utils.templates import evaluate_condition, evaluate_template
 
 PDF_FILE_OBJECT = {
     'type': 'object',
@@ -80,50 +82,36 @@ ASSEMBLE_SCHEMA = {
     ),
 }
 
-FILL_FORM_SCHEMA = {
-    '$schema': 'http://json-schema.org/draft-04/schema#',
-    'title': '',
-    'description': '',
-    'type': 'object',
-    'required': ['filename', 'fields'],
-    'unflatten': True,
-    'properties': OrderedDict(
-        {
-            'filename': {
-                'description': _('output PDF filename'),
-                'type': 'string',
-            },
-            'input-form': PDF_FILE_OBJECT,
-            'fields': {
-                'description': _('hierarchical dictionary of fields'),
-                'type': 'object',
-            },
-        }
-    ),
-}
-
 
 def validate_pdf(fieldfile):
-    fieldfile.open()
-    if fieldfile.read(5) != b'%PDF-':
-        raise ValidationError(
-            _('%(value)s is not a PDF file'),
-            params={'value': fieldfile},
-        )
+    to_close = fieldfile.closed
+    try:
+        if fieldfile.read(5) != b'%PDF-':
+            raise ValidationError(
+                _('%(value)s is not a PDF file'),
+                params={'value': fieldfile},
+            )
+    finally:
+        if to_close:
+            fieldfile.close()
 
 
 class Resource(BaseResource):
     category = _('Misc')
 
     fill_form_file = models.FileField(
-        _('Fill Form default input file'),
+        _('Fill Form input file'),
         upload_to=resource_file_upload_to,
-        help_text=_('PDF file, used if not input-form in fill-form payload'),
+        help_text=_('PDF file'),
         validators=[validate_pdf],
         null=True,
         blank=True,
     )
 
+    fields_mapping = JSONField(verbose_name=_('Field mapping'), null=True, blank=True)
+
+    hide_description_fields = ['fields_mapping']
+
     class Meta:
         verbose_name = _('PDF')
 
@@ -182,77 +170,86 @@ class Resource(BaseResource):
         response['Content-Disposition'] = 'attachment; filename="%s"' % filename
         return response
 
+    FILL_FORM_SCHEMA = {
+        '$schema': 'http://json-schema.org/draft-04/schema#',
+        'title': '',
+        'description': _('content of the form to map on PDF fields'),
+        'unflatten': True,
+        'type': 'object',
+        'properties': OrderedDict(
+            {
+                'extra': {
+                    'type': 'object',
+                    'properties': OrderedDict(
+                        {
+                            'filename': {
+                                'type': 'string',
+                                'description': _('file name'),
+                            },
+                            'flatten': {
+                                'description': _('remove PDF fields, keep only the drawed values'),
+                                'type': 'boolean',
+                            },
+                        }
+                    ),
+                }
+            }
+        ),
+    }
+
     @endpoint(
         name='fill-form',
-        description=_('Fills the input PDF form with fields'),
+        description=_('Fills the input PDF form with fields applying mappings to the received payload'),
         perm='can_access',
         methods=['post'],
+        parameters={
+            'filename': {'description': _('file name')},
+            'flatten': {'description': _('remove PDF fields, keep only the drawed values')},
+        },
         post={
             'request_body': {'schema': {'application/json': FILL_FORM_SCHEMA}},
             'input_example': {
-                'filename': 'filled.pdf',
-                'fields/Page1[0]/FirstName[0]': 'John',
-                'fields/Page1[0]/LastName[0]': 'Doe',
-                'fields/Page2[0]/Checkbox[0]': '0',
-                'fields/Page2[0]/Checkbox[1]': '1',
+                'extra': {
+                    'filename': 'filled.pdf',
+                    'flatten': True,
+                },
+                'prenom': 'Jean',
+                'nom': 'Dupont',
             },
         },
     )
-    def fill_form(self, request, post_data):
-        filename = post_data.pop('filename')
-        fields = post_data.pop('fields')
+    def fill_form(self, request, post_data, flatten=None, filename=None):
+        extra = post_data.pop('extra', {})
+        filename = filename or extra.get('filename') or post_data.get('filename') or 'form.pdf'
+        flatten_pdf = str(flatten or extra.get('flatten') or post_data.get('flatten')).lower() in (
+            '1',
+            'on',
+            'yes',
+            'true',
+        )
 
-        xfdf_root = ET.Element('xfdf')
-        xfdf_root.attrib['xmlns'] = 'http://ns.adobe.com/xfdf/'
-        xfdf_root.attrib['xml:space'] = 'preserve'
-        xfdf_f = ET.SubElement(xfdf_root, 'f')
-        xfdf_fields = ET.SubElement(xfdf_root, 'fields')
-
-        def add_fields(element, fields):
-            if isinstance(fields, dict):
-                for key in fields:
-                    field = ET.SubElement(element, 'field')
-                    field.attrib['name'] = key
-                    add_fields(field, fields[key])
-            else:
-                value = ET.SubElement(element, 'value')
-                value.text = str(fields)
-
-        add_fields(xfdf_fields, fields)
-
-        with tempfile.TemporaryDirectory(prefix='passerelle-pdftk-%s-fill-form-' % self.id) as tmpdir:
-            if isinstance(post_data.get('input-form'), dict) and post_data['input-form'].get('content'):
-                input_filename = os.path.join(tmpdir, 'input-form.pdf')
-                with open(input_filename, mode='wb') as fd:
-                    fd.write(base64.b64decode(post_data['input-form']['content']))
-            elif self.fill_form_file:
-                input_filename = self.fill_form_file.path
-            else:
-                raise APIError("missing or bad 'input-form' property", http_status=400)
-            # create xfdf
-            xfdf_filename = os.path.join(tmpdir, 'fields.xfdf')
-            xfdf_f.attrib['href'] = input_filename
-            with open(xfdf_filename, mode='wb') as fd:
-                ET.indent(xfdf_root)
-                ET.ElementTree(xfdf_root).write(fd, encoding='UTF-8', xml_declaration=True)
-
-            # call pdftk fill_form
-            pdf_content = self.run_pdftk(args=[input_filename, 'fill_form', xfdf_filename])
-
-        response = HttpResponse(pdf_content, content_type='application/pdf')
-        response['Content-Disposition'] = 'attachment; filename="%s"' % filename
-        return response
-
-    def pdftk_dump_data_fields_utf8(self):
         if not self.fill_form_file:
-            return
-        try:
-            dump = self.run_pdftk(args=[self.fill_form_file.path, 'dump_data_fields_utf8']).decode()
-        except APIError as apierror:
-            return 'Error: %r' % apierror
-        unflatten_separated = ''
-        for line in dump.splitlines():
-            unflatten_separated += '<br>%s' % line
-            if line.startswith('FieldName: '):
-                unflatten_separated += ' → <b>fields/%s</b>' % line[11:].replace('.', '/')
-        return unflatten_separated
+            raise APIError('not PDF file configured')
+        fields_mapping = self.fields_mapping
+        if not fields_mapping:
+            raise APIError('no fields mapping configured')
+
+        with self.fill_form_file.open() as fd:
+            pdf = PDF(fd)
+            for page in pdf.pages:
+                for field in page.fields:
+                    mapping_template = fields_mapping.get(f'field_{field.digest_id}')
+                    if not mapping_template:
+                        continue
+                    if field.widget_type == 'checkbox':
+                        value = evaluate_condition(mapping_template, post_data)
+                    elif field.widget_type == 'text':
+                        value = evaluate_template(mapping_template, post_data)
+                    else:
+                        raise NotImplementedError
+                    if value is not None:
+                        field.set(value)
+        response = HttpResponse(content_type='application/pdf')
+        response['Content-Disposition'] = 'attachment; filename="%s"' % filename
+        pdf.write(response, flatten=flatten_pdf)
+        return response

passerelle/apps/pdf/templates/pdf/fields_mapping_edit.html

@@ -0,0 +1,74 @@
+{% extends "passerelle/manage/resource_child_base.html" %}
+{% load i18n gadjo %}
+
+{% block breadcrumb %}
+  <a href="{% url 'manage-home' %}">{% trans 'Web Services' %}</a>
+  <a href="{{ object.get_absolute_url }}">PDF &mdash; {{ object.title }}</a>
+  <a href="#">{% trans "Edit fields mapping" %}</a>
+{% endblock %}
+
+{% block appbar %}
+  <h2>
+    {% trans "Edit fields mapping" %}
+  </h2>
+{% endblock %}
+
+{% block content %}
+  <form method="post" enctype="multipart/form-data" class="pdf-fields-mapping-edit-form">
+    {% csrf_token %}
+    <div class="buttons pdf-fields-mapping-edit-form--buttons">
+      <button class="submit-button">{% trans "Save" %}</button>
+      <a class="cancel" href="{{ object.get_absolute_url }}">{% trans 'Cancel' %}</a>
+    </div>
+    {% if form.errors %}
+      <div class="errornotice" tabindex="-1" autofocus>
+        <p>{% trans "There were errors processing your form." %}</p>
+        {% for error in form.non_field_errors %}
+          <p>{{ error }}</p>
+        {% endfor %}
+        {% for field in form %}
+          {% if field.is_hidden and field.errors %}
+            <p>
+              {% for error in field.errors %}
+                {% blocktrans with name=field.name %}(Hidden field {{name}}) {{ error }}{% endblocktrans %}
+                {% if not forloop.last %}<br>{% endif %}
+              {% endfor %}
+            </p>
+          {% endif %}
+        {% endfor %}
+      </div>
+    {% endif %}
+    {% for page_number, image_map in pages %}
+      <h3>{% blocktrans with number=page_number|add:1 %}Page {{number}}{% endblocktrans %}</h3>
+      <div class="pdf-fields-mapping-edit-form--page">
+        <div class="pdf-fields-mapping-edit-form--thumbnail">
+          <div>
+            <map name="map-page-{{ page_number }}">
+              {{ image_map|safe }}
+            </map>
+            <img src="{% url "pdf-page-thumbnail" connector="pdf" slug=object.slug page_number=page_number %}" usemap="#map-page-{{ page_number }}">
+          </div>
+        </div>
+        <div class="pdf-fields-mapping-edit-form--fields">
+          {% for field in form %}
+            {% if field.field.page_number == page_number %}
+              {% include "gadjo/widget.html" with field=field %}
+            {% endif %}
+          {% endfor %}
+        </div>
+      </div>
+    {% endfor %}
+    <div class="buttons pdf-fields-mapping-edit-form--buttons">
+      <button class="submit-button">{% trans "Save" %}</button>
+      <a class="cancel" href="{{ object.get_absolute_url }}">{% trans 'Cancel' %}</a>
+    </div>
+  </form>
+  <script>
+    $(document).on('click', 'area', function (event) {
+      var $target = $(event.target);
+      var href = $target.attr('href');
+      $('.pdf-fields-mapping-edit-form--fields').scrollTop = $(href).offsetTop;
+      $(href + ' input').focus();
+    })
+  </script>
+{% endblock %}

passerelle/apps/pdf/templates/pdf/resource_detail.html

@@ -1,20 +1,8 @@
 {% extends "passerelle/manage/service_view.html" %}
 {% load i18n passerelle %}
 
-{% block extra-tab-buttons %}
-  {% if user.is_staff and object.fill_form_file %}
-    <button role="tab" aria-selected="false" aria-controls="panel-dumpfields" id="tab-dumpfields"
-      tabindex="-1">{% trans "Fill Form default PDF Fields" %}</button>
-  {% endif %}
-{% endblock %}
-
-{% block extra-tab-panels %}
-  {% if user.is_staff and object.fill_form_file %}
-    <div id="panel-dumpfields" role="tabpanel" tabindex="-1" aria-labelledby="tab-dumpfields" hidden>
-      <div>
-        <p>{% blocktrans with file=object.fill_form_file %}PDFtk {{ file }} dump_data_fields_utf8 output{% endblocktrans %}</p>
-        <p>{{ object.pdftk_dump_data_fields_utf8|safe }}</p>
-      </div>
-    </div>
+{% block actions %}
+  {% if object|can_edit:request.user %}
+    <a href="{% url 'pdf-fields-mapping-edit' connector='pdf' slug=object.slug %}">{% trans 'Fill form: Edit fields mapping' %}</a>
   {% endif %}
 {% endblock %}

passerelle/apps/pdf/urls.py

@@ -0,0 +1,32 @@
+# passerelle - uniform access to multiple data sources and services
+# Copyright (C) 2019 Entr'ouvert
+#
+# This program is free software: you can redistribute it and/or modify it
+# under the terms of the GNU Affero General Public License as published
+# by the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from django.urls import re_path
+
+from . import views
+
+management_urlpatterns = [
+    re_path(
+        r'^(?P<slug>[\w,-]+)/fields-mapping/edit/$',
+        views.FieldsMappingEditView.as_view(),
+        name='pdf-fields-mapping-edit',
+    ),
+    re_path(
+        r'^(?P<slug>[\w,-]+)/page/(?P<page_number>[0-9]+)/$',
+        views.PageThumbnailView.as_view(),
+        name='pdf-page-thumbnail',
+    ),
+]

passerelle/apps/pdf/views.py

@@ -0,0 +1,94 @@
+# passerelle - uniform access to multiple data sources and services
+# Copyright (C) 2019 Entr'ouvert
+#
+# This program is free software: you can redistribute it and/or modify it
+# under the terms of the GNU Affero General Public License as published
+# by the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import hashlib
+import io
+
+import PIL.Image
+import PIL.ImageDraw
+from django.http import Http404, HttpResponse, HttpResponseNotModified
+from django.utils.translation import gettext_lazy as _
+from django.views.generic import UpdateView
+
+from passerelle.base.views import ResourceView
+from passerelle.utils.pdf import PDF
+
+from . import forms, models
+
+
+class FieldsMappingEditView(ResourceView, UpdateView):
+    template_name = 'pdf/fields_mapping_edit.html'
+    model = models.Resource
+    form_class = forms.FieldsMappingEditForm
+
+    def get_context_data(self, **kwargs):
+        context_data = super().get_context_data(**kwargs)
+        resource = self.get_object()
+        with resource.fill_form_file as fd:
+            pdf = PDF(fd)
+        pages = []
+        for page in pdf.pages:
+            pages.append((page.page_number, page.fields_image_map(id_prefix='id_field_', id_suffix='_p')))
+        context_data['pages'] = pages
+        return context_data
+
+    def get_success_url(self):
+        return super().get_success_url() + '#'
+
+
+class PageThumbnailView(ResourceView):
+    model = models.Resource
+
+    def make_thumbnail(self, page):
+        # produce a thumbnail and add
+        # * red rectangle over field's rectangles
+        # * enumerated field names
+        thumbnail = page.thumbnail_png()
+        image = PIL.Image.open(io.BytesIO(thumbnail))
+        draw = PIL.ImageDraw.Draw(image, 'RGBA')
+        for i, (field, area_rect) in enumerate(page.thumbnail_field_rects()):
+            draw.rectangle(area_rect, fill=(255, 0, 0, 50))
+            x = area_rect.x1
+            y = (area_rect.y1 + area_rect.y2) / 2 - 5
+            if field.widget_type == 'checkbox':
+                y -= 10
+            draw.text((x, y), str(_('field %s') % (i + 1)), anchor='lb', fill=(0, 0, 0, 255))
+        del draw
+        output = io.BytesIO()
+        image.save(output, 'PNG')
+        return output.getvalue()
+
+    def get(self, request, page_number, **kwargs):
+        with self.get_object().fill_form_file as fd:
+            pdf_content = fd.read()
+
+        etag = hashlib.md5(pdf_content).hexdigest()
+        if_none_match = request.headers.get('If-None-Match', '').split(',')
+        if etag in if_none_match:
+            # use browser cache
+            response = HttpResponseNotModified()
+        else:
+            # produce the thumbnail
+            pdf = PDF(pdf_content)
+            try:
+                page = pdf.page(int(page_number))
+            except IndexError:
+                raise Http404
+            thumbnail_content = self.make_thumbnail(page)
+            response = HttpResponse(thumbnail_content, content_type='image/png')
+        response['ETag'] = etag
+        response['Cache-Control'] = 'max-age=3600'
+        return response

passerelle/static/css/style.scss

@@ -407,3 +407,31 @@ ul.get-params li {
 		min-height: 200px;
 	}
 }
+
+/* passerelle/apps/pdf/templates/pdf/field_mapping_edit.html */
+.pdf-fields-mapping-edit-form--page {
+	display: flex;
+	height: max-content;
+}
+
+.pdf-fields-mapping-edit-form--fields {
+	height: 1132px;
+	overflow-y: scroll;
+	> .widget textarea, > .widget input {
+		width: 100%;
+	}
+	.widget:target {
+		border: 2px dashed #FFAAAA;
+	}
+
+}
+
+.pdf-fields-mapping-edit-form--thumbnail {
+	position: sticky;
+	top: 0;
+}
+
+.pdf-fields-mapping-edit-form--thumbnail, .pdf-fields-mapping-edit-form--fields {
+	margin-right: 1em;
+	flex: 1;
+}

passerelle/utils/forms.py

@@ -15,8 +15,34 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 from django import forms
-from django.core import validators
+from django.core import exceptions, validators
+from django.template import Template, TemplateSyntaxError
+from django.utils.translation import gettext_lazy as _
 
 
 class LDAPURLField(forms.URLField):
     default_validators = [validators.URLValidator(schemes=['ldap', 'ldaps'])]
+
+
+def validate_condition_template(condition_template):
+    real_template = f'{{% if {condition_template} %}}OK{{% endif %}}'
+    try:
+        Template(real_template)
+    except (TemplateSyntaxError, OverflowError) as e:
+        raise exceptions.ValidationError(_('syntax error: %s') % e, code='syntax-error')
+
+
+class ConditionField(forms.CharField):
+    default_validators = [validate_condition_template]
+
+
+def validate_template(template):
+    try:
+        Template(template)
+    except (TemplateSyntaxError, OverflowError) as e:
+        raise exceptions.ValidationError(_('syntax error: %s') % e, code='syntax-error')
+
+
+class TemplateField(forms.CharField):
+    default_validators = [validate_template]
+    widget = forms.Textarea

passerelle/utils/pdf.py

@@ -0,0 +1,249 @@
+# passerelle - uniform access to multiple data sources and services
+# Copyright (C) 2023 Entr'ouvert
+#
+# This program is free software: you can redistribute it and/or modify it
+# under the terms of the GNU Affero General Public License as published
+# by the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import base64
+import dataclasses
+import functools
+import hashlib
+import io
+import subprocess
+import tempfile
+import typing
+
+import pdfrw
+
+
+class Rect(typing.NamedTuple):
+    x1: float
+    y1: float
+    x2: float
+    y2: float
+
+
+@dataclasses.dataclass(frozen=True)
+class Widget:
+    page: 'Page' = dataclasses.field(compare=False, repr=False)
+    name: str
+    widget_type: str = dataclasses.field(compare=False)
+    rect: Rect = dataclasses.field(compare=False)
+    on_value: str = dataclasses.field(compare=False, default=pdfrw.PdfName.On)
+    annotation: pdfrw.PdfDict = dataclasses.field(default=None, repr=False)
+
+    @property
+    def digest_id(self):
+        if not self.name:
+            return ''
+        name_bytes = self.name.encode()
+        digest_algo = hashlib.md5(name_bytes)
+        digest = digest_algo.digest()
+        b32_encoded = base64.b32encode(digest).decode()
+        return b32_encoded.strip('=').upper()
+
+    @property
+    def value(self):
+        if self.widget_type == 'text':
+            if self.annotation[pdfrw.PdfName.V]:
+                return self.annotation[pdfrw.PdfName.V].decode()
+            return ''
+        elif self.widget_type == 'checkbox':
+            return self.annotation[pdfrw.PdfName.V] == self.on_value
+
+    def set(self, value):
+        # allow rendering of values in Acrobat Reader
+        self.page.pdf._pdf_reader.Root.AcroForm.update(pdfrw.PdfDict(NeedAppearances=pdfrw.PdfObject('true')))
+        if self.widget_type == 'text':
+            str_value = str(value)
+            self.annotation.update(pdfrw.PdfDict(V=str_value, AS=str_value))
+        elif self.widget_type == 'checkbox':
+            bool_value = self.on_value if value else pdfrw.PdfName.Off
+            self.annotation.update(pdfrw.PdfDict(V=bool_value, AS=bool_value))
+
+
+@dataclasses.dataclass
+class Page:
+    pdf: object
+    page_number: object
+
+    THUMBNAIL_DEFAULT_WIDTH = 800
+
+    @property
+    def page(self):
+        return self.pdf._pdf_reader.pages[self.page_number]
+
+    @property
+    def fields(self):
+        fields = []
+        for annotation in self.page[pdfrw.PdfName.Annots] or ():
+            if annotation[pdfrw.PdfName.Subtype] != pdfrw.PdfName.Widget:
+                continue
+            if not annotation[pdfrw.PdfName.T]:
+                continue
+            name = annotation[pdfrw.PdfName.T].decode()
+            parent = annotation[pdfrw.PdfName.Parent]
+            while parent and parent[pdfrw.PdfName.T]:
+                name = f'{parent[pdfrw.PdfName.T].decode()}.{name}'
+                parent = parent[pdfrw.PdfName.Parent]
+            if not annotation[pdfrw.PdfName.FT]:
+                continue
+            pdf_field_type = annotation[pdfrw.PdfName.FT]
+            pdf_field_flags = annotation[pdfrw.PdfName.Ff] or 0
+            RADIO_FLAG = 2**16
+            PUSH_BUTTON_FLAG = 2**17
+            if (
+                pdf_field_type == pdfrw.PdfName.Btn
+                and not (pdf_field_flags & RADIO_FLAG)
+                and not (pdf_field_flags & PUSH_BUTTON_FLAG)
+            ):
+                widget_type = 'checkbox'
+            elif pdf_field_type == pdfrw.PdfName.Tx:
+                widget_type = 'text'
+            else:
+                continue
+            on_value = None
+            if widget_type == 'checkbox':
+                try:
+                    on_values = list(annotation[pdfrw.PdfName.AP][pdfrw.PdfName.N].keys())
+                except KeyError:
+                    on_value = pdfrw.PdfName.On
+                else:
+                    if pdfrw.PdfName.Off in on_values:
+                        on_values.remove(pdfrw.PdfName.Off)
+                    on_value = on_values[0]
+            fields.append(
+                Widget(
+                    name=name,
+                    widget_type=widget_type,
+                    rect=Rect(*map(float, annotation[pdfrw.PdfName.Rect])),
+                    on_value=on_value,
+                    page=self,
+                    annotation=annotation,
+                )
+            )
+        fields.sort(key=lambda field: (-field.rect[1], field.rect[0]))
+        return fields
+
+    @property
+    def media_box(self):
+        return Rect(*map(float, self.page[pdfrw.PdfName.MediaBox]))
+
+    def thumbnail_png(self, width=None):
+        width = width or self.THUMBNAIL_DEFAULT_WIDTH
+
+        fp = io.BytesIO(
+            subprocess.check_output(
+                [
+                    'pdftoppm',
+                    '-png',
+                    '-scale-to-x',
+                    str(width or '-1'),
+                    '-scale-to-y',
+                    '-1',
+                    '-f',
+                    str(self.page_number + 1),
+                    '-l',
+                    str(self.page_number + 1),
+                    '-',
+                ],
+                stderr=subprocess.DEVNULL,
+                input=self.pdf.content,
+            )
+        )
+        return fp.getvalue()
+
+    def thumbnail_field_rects(self, width=None):
+        '''Transform coordinates of fields to coordindates in thumbnail image.'''
+        width = width or self.THUMBNAIL_DEFAULT_WIDTH
+        media_box = self.media_box
+        media_width = media_box.x2 - media_box.x1
+        media_height = media_box.y2 - media_box.y1
+        height = int(width / media_width * media_height)
+
+        for field in self.fields:
+            field_rect = field.rect
+            yield field, Rect(
+                # PDF coordinates origin is in the bottom-left corner but img
+                # tag origin is in the top-left corner
+                x1=int((field_rect.x1 - media_box.x1) / media_width * width),
+                y1=int((media_box.y2 - field_rect.y1) / media_height * height),
+                x2=int((field_rect.x2 - media_box.x1) / media_width * width),
+                y2=int((media_box.y2 - field_rect.y2) / media_height * height),
+            )
+
+    def fields_image_map(self, width=None, sep='\n', id_prefix='', id_suffix=''):
+        tags = []
+        for field, area_rect in self.thumbnail_field_rects(width=width):
+            coords = ','.join(map(str, area_rect))
+            tags.append(
+                f'<area shape="rect" '
+                f'href="#{id_prefix}{field.digest_id}{id_suffix}" '
+                f'coords="{coords}">'
+            )
+        return sep.join(tags)
+
+
+class PDF:
+    def __init__(self, content):
+        if hasattr(content, 'read'):
+            content = content.read()
+        self.content = content
+
+    @functools.cached_property
+    def _pdf_reader(self):
+        return pdfrw.PdfReader(fdata=self.content)
+
+    @property
+    def number_of_pages(self):
+        return len(self._pdf_reader.pages)
+
+    def page(self, page_number):
+        return Page(pdf=self, page_number=page_number)
+
+    @property
+    def pages(self):
+        for i in range(self.number_of_pages):
+            yield self.page(i)
+
+    def write(self, file_object, flatten=False):
+        assert hasattr(file_object, 'write')
+        if not flatten:
+            pdfrw.PdfWriter().write(file_object, self._pdf_reader)
+        else:
+            with io.BytesIO() as fd:
+                pdfrw.PdfWriter().write(fd, self._pdf_reader)
+                original_content = fd.getvalue()
+
+                with tempfile.NamedTemporaryFile() as output:
+                    try:
+                        subprocess.check_output(
+                            [
+                                'gs',
+                                '-dSAFER',
+                                '-dBATCH',
+                                '-dNOPAUSE',
+                                '-dNOCACHE',
+                                '-sDEVICE=pdfwrite',
+                                '-dPreserveAnnots=false',
+                                f'-sOutputFile={output.name}',
+                                '-',
+                            ],
+                            stderr=subprocess.DEVNULL,
+                            input=original_content,
+                        )
+                    except subprocess.CalledProcessError as e:
+                        raise Exception(f'gs error={e.returncode} output={e.output}')
+                    output.seek(0)
+                    new_content = output.read()
+                file_object.write(new_content)

passerelle/utils/templates.py

@@ -20,7 +20,7 @@ Disable autoescaping.
 '''
 
 from django.core.exceptions import ValidationError
-from django.template import TemplateSyntaxError
+from django.template import Context, Template, TemplateSyntaxError
 from django.template.backends.django import DjangoTemplates
 from django.utils.translation import gettext as _
 
@@ -46,3 +46,15 @@ def validate_template(template_string):
         make_template(template_string)
     except TemplateSyntaxError as e:
         raise ValidationError(_('Invalid template: %s') % e)
+
+
+def evaluate_condition(condition_template, context_dict):
+    template = Template(f'{{% if {condition_template} %}}OK{{% endif %}}')
+    context = Context(context_dict)
+    return template.render(context) == 'OK'
+
+
+def evaluate_template(template, context_dict):
+    template = Template(template)
+    context = Context(context_dict)
+    return template.render(context)

tests/test_pdf.py

@@ -17,17 +17,17 @@
 import base64
 import os
 import subprocess
-import xml.etree.ElementTree as ET
 from io import BytesIO
 from unittest import mock
 
 import pytest
 from django.core.exceptions import ValidationError
 from django.core.files import File
-from django.urls import reverse
+from django.core.files.base import ContentFile
 from pdfrw import PdfReader
 
 from passerelle.apps.pdf.models import Resource
+from passerelle.utils.pdf import PDF
 from tests.test_manager import login
 from tests.utils import generic_endpoint_url, setup_access_rights
 
@@ -139,145 +139,6 @@ def test_pdf_real_pdftk_assemble(app, pdf, settings):
     assert PdfReader(fdata=resp.content).numPages == 2
 
 
-@mock.patch('subprocess.check_output')
-def test_pdf_fill_form(mocked_check_output, app, pdf):
-    endpoint = generic_endpoint_url('pdf', 'fill-form', slug=pdf.slug)
-
-    def check_xml(args, **kwargs):
-        # check XML FDF file
-        xfdf = ET.parse(args[3]).getroot()
-        assert xfdf.tag == '{http://ns.adobe.com/xfdf/}xfdf'
-        assert xfdf.find('{http://ns.adobe.com/xfdf/}f').attrib['href'].endswith('.pdf')
-        field = xfdf.find('{http://ns.adobe.com/xfdf/}fields').find('{http://ns.adobe.com/xfdf/}field')
-        assert field.attrib['name'] == 'fname'
-        assert field.find('{http://ns.adobe.com/xfdf/}value').text == 'John'
-
-    payload = {
-        'filename': 'foo.pdf',
-        'fields/fname': 'John',
-        'input-form': {'content': acroform_b64content},
-    }
-    mocked_check_output.side_effect = check_xml
-    resp = app.post_json(endpoint, params=payload, status=200)
-    assert resp.headers['content-type'] == 'application/pdf'
-    assert resp.headers['content-disposition'] == 'attachment; filename="foo.pdf"'
-    assert mocked_check_output.call_count == 1
-    pdftk_call = mocked_check_output.call_args.args[0]
-    assert len(pdftk_call) == 6
-    assert pdftk_call[0] == '/usr/bin/pdftk'
-    assert pdftk_call[1].endswith('/input-form.pdf')
-    assert pdftk_call[2] == 'fill_form'
-    assert pdftk_call[3].endswith('/fields.xfdf')
-    assert pdftk_call[4] == 'output'
-    assert pdftk_call[5] == '-'
-    assert mocked_check_output.call_args.kwargs['timeout'] == 20
-
-    pdf.fill_form_file = File(BytesIO(acroform_content), 'default.pdf')
-    pdf.save()
-    payload = {
-        'filename': 'bar.pdf',
-        'fields/fname': 'John',
-    }
-    mocked_check_output.reset_mock()
-    resp = app.post_json(endpoint, params=payload, status=200)
-    assert resp.headers['content-type'] == 'application/pdf'
-    assert resp.headers['content-disposition'] == 'attachment; filename="bar.pdf"'
-    assert mocked_check_output.call_count == 1
-    pdftk_call = mocked_check_output.call_args.args[0]
-    assert len(pdftk_call) == 6
-    assert pdftk_call[0] == '/usr/bin/pdftk'
-    assert pdftk_call[1].endswith('media/pdf/test/default.pdf')
-    assert pdftk_call[2] == 'fill_form'
-    assert pdftk_call[3].endswith('/fields.xfdf')
-    assert pdftk_call[4] == 'output'
-    assert pdftk_call[5] == '-'
-    assert mocked_check_output.call_args.kwargs['timeout'] == 20
-
-    # pdftk errors (faked)
-    payload = {
-        'filename': 'foo.pdf',
-        'fields/fname': 'Bill',
-        'input-form': {'content': acroform_b64content},
-    }
-    mocked_check_output.reset_mock()
-    mocked_check_output.side_effect = subprocess.TimeoutExpired(cmd=[], timeout=20)
-    resp = app.post_json(endpoint, params=payload, status=200)
-    assert mocked_check_output.call_count == 1
-    assert resp.json['err'] == 1
-    assert resp.json['err_desc'].startswith('pdftk timed out after 20 seconds')
-
-    mocked_check_output.reset_mock()
-    mocked_check_output.side_effect = subprocess.CalledProcessError(cmd=[], returncode=42, output='ooops')
-    resp = app.post_json(endpoint, params=payload, status=200)
-    assert mocked_check_output.call_count == 1
-    assert resp.json['err'] == 1
-    assert resp.json['err_desc'].startswith('pdftk returned non-zero exit status 42')
-    assert 'ooops' in resp.json['err_desc']
-
-    # bad calls errors
-    resp = app.post(endpoint, status=400)
-    assert resp.headers['content-type'].startswith('application/json')
-    assert resp.json['err'] == 1
-    assert resp.json['err_desc'].startswith('could not decode body to json')
-
-    payload = {}
-    resp = app.post_json(endpoint, params=payload, status=400)
-    assert resp.json['err'] == 1
-    assert resp.json['err_desc'] == "'filename' is a required property"
-
-    payload = {'filename': 'out.pdf'}
-    resp = app.post_json(endpoint, params=payload, status=400)
-    assert resp.json['err'] == 1
-    assert resp.json['err_desc'] == "'fields' is a required property"
-
-    payload = {'filename': 'out.pdf', 'fields': 'not-a-dict'}
-    resp = app.post_json(endpoint, params=payload, status=400)
-    assert resp.json['err'] == 1
-    assert resp.json['err_desc'] == "fields: 'not-a-dict' is not of type 'object'"
-
-    pdf.fill_form_file = None  # no default PDF form
-    pdf.save()
-    payload = {
-        'filename': 'bar.pdf',
-        'fields/fname': 'Alice',
-    }
-    resp = app.post_json(endpoint, params=payload, status=400)
-    assert resp.json['err'] == 1
-    assert resp.json['err_desc'] == "missing or bad 'input-form' property"
-
-    resp = app.get(endpoint, status=405)
-
-
-def test_pdf_real_pdftk_fillform(admin_user, app, pdf, settings):
-    if not os.path.exists(settings.PDFTK_PATH):
-        pytest.skip('pdftk (%s) not found' % settings.PDFTK_PATH)
-
-    endpoint = generic_endpoint_url('pdf', 'fill-form', slug=pdf.slug)
-    payload = {
-        'filename': 'filled.pdf',
-        'fields/fname': 'ThisIsMyFirstName',
-        'input-form': {'content': acroform_b64content},
-    }
-    resp = app.post_json(endpoint, params=payload, status=200)
-    assert resp.headers['content-type'] == 'application/pdf'
-    assert resp.headers['content-disposition'] == 'attachment; filename="filled.pdf"'
-    assert PdfReader(fdata=resp.content).numPages == 1
-    assert resp.content[:5] == b'%PDF-'
-    # TODO: found an easy way to verify 'ThisIsMyFirstName' in resp.content
-
-    # dump fields in manager view
-    pdf.fill_form_file = File(BytesIO(acroform_content), 'pdf-form.pdf')
-    pdf.save()
-    manage_url = reverse('view-connector', kwargs={'connector': 'pdf', 'slug': pdf.slug})
-    resp = app.get(manage_url)
-    assert 'panel-dumpfields' not in resp.text
-    assert '<b>fields/fname</b>' not in resp.text
-    app = login(app)
-    resp = app.get(manage_url)
-    assert 'panel-dumpfields' in resp.text
-    assert '<b>fields/fname</b>' in resp.text
-
-
 def test_pdf_validator(pdf):
     pdf.fill_form_file = File(BytesIO(pdf_content), 'default.pdf')
     pdf.save()
@@ -291,3 +152,64 @@ def test_pdf_validator(pdf):
     pdf.save()
     with pytest.raises(ValidationError):
         pdf.full_clean()
+
+
+@pytest.fixture
+def cerfa_content():
+    with open('tests/data/cerfa_10072-02.pdf', 'rb') as fd:
+        return fd.read()
+
+
+def test_fill_form_no_pdf(app, admin_user, pdf):
+    resp = app.post_json('/pdf/test/fill-form/', params={'a': 1})
+    assert resp.json == {
+        'data': None,
+        'err': 1,
+        'err_class': 'passerelle.utils.jsonresponse.APIError',
+        'err_desc': 'not PDF file configured',
+    }
+
+
+def test_fill_form_no_fields_mapping(app, admin_user, pdf, cerfa_content):
+    pdf.fill_form_file.save('form.pdf', ContentFile(cerfa_content))
+    resp = app.post_json('/pdf/test/fill-form/', params={'a': 1})
+    assert resp.json == {
+        'data': None,
+        'err': 1,
+        'err_class': 'passerelle.utils.jsonresponse.APIError',
+        'err_desc': 'no fields mapping configured',
+    }
+
+
+def test_fill_form_ok(app, admin_user, pdf, cerfa_content):
+    pdf.fill_form_file.save('form.pdf', ContentFile(cerfa_content))
+    app = login(app)
+    resp = app.get('/pdf/test/')
+    resp = resp.click('Fill form: Edit fields mapping')
+    img_tags = resp.pyquery('img')
+    image_resp = app.get(img_tags[0].attrib['src'])
+    assert b'PNG' in image_resp.content
+    pdf_ = PDF(cerfa_content)
+    page = pdf_.page(0)
+    checkbox_field = [field for field in page.fields if field.widget_type == 'checkbox'][0]
+    text_field = [field for field in page.fields if field.widget_type == 'text'][0]
+    assert checkbox_field.value is False
+    assert text_field.value == ''
+    resp.form.set(f'field_{checkbox_field.digest_id}', 'testme == "a"')
+    resp.form.set(f'field_{text_field.digest_id}', '{{ prenom }} {{ nom }}')
+    resp.form.submit().follow()
+
+    resp = app.post_json('/pdf/test/fill-form/', params={'testme': 'a', 'prenom': 'Jean', 'nom': 'Dupont'})
+    pdf_ = PDF(resp.content)
+    page = pdf_.page(0)
+    checkbox_field = [field for field in page.fields if field.widget_type == 'checkbox'][0]
+    text_field = [field for field in page.fields if field.widget_type == 'text'][0]
+    assert checkbox_field.value is True
+    assert text_field.value == 'Jean Dupont'
+
+    resp = app.post_json(
+        '/pdf/test/fill-form/?flatten=1', params={'testme': 'a', 'prenom': 'Jean', 'nom': 'Dupont'}
+    )
+    pdf_ = PDF(resp.content)
+    page = pdf_.page(0)
+    assert not page.fields

tests/test_utils_forms.py

@@ -0,0 +1,34 @@
+# passerelle - uniform access to multiple data sources and services
+# Copyright (C) 2023 Entr'ouvert
+#
+# This program is free software: you can redistribute it and/or modify it
+# under the terms of the GNU Affero General Public License as published
+# by the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import pytest
+from django.core.exceptions import ValidationError
+
+from passerelle.utils.forms import ConditionField, TemplateField
+
+
+def test_condition_field():
+    field = ConditionField()
+    with pytest.raises(ValidationError):
+        field.clean('x ==')
+    assert field.clean('x == 1') == 'x == 1'
+
+
+def test_template_field():
+    field = TemplateField()
+    with pytest.raises(ValidationError):
+        field.clean('{% if foo %}bar')
+    assert field.clean('{% if foo %}bar{% endif %}') == '{% if foo %}bar{% endif %}'

tests/test_utils_pdf.py

@@ -0,0 +1,95 @@
+# passerelle - uniform access to multiple data sources and services
+# Copyright (C) 2023 Entr'ouvert
+#
+# This program is free software: you can redistribute it and/or modify it
+# under the terms of the GNU Affero General Public License as published
+# by the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import io
+import re
+
+import pytest
+from PIL import Image
+
+from passerelle.utils.pdf import PDF
+
+
+@pytest.fixture
+def pdf():
+    with open('tests/data/cerfa_10072-02.pdf', 'rb') as fd:
+        return PDF(content=fd)
+
+
+def test_number_of_pages(pdf):
+    assert pdf.number_of_pages == 5
+
+
+def test_page(pdf):
+    assert pdf.page(0) is not None
+    assert pdf.page(0).media_box == (0, 0, 595.32, 841.92)
+
+
+def test_page_len_fields(pdf):
+    assert len(list(pdf.page(0).fields)) == 53
+
+
+def test_page_fields(pdf):
+    page = pdf.page(0)
+    field = page.fields[0]
+    assert field.name == 'topmostSubform[0].Page1[0].Case_à_cocher1[2]'
+    assert field.widget_type == 'checkbox'
+    assert field.rect == (550.292, 691.02, 558.292, 699.02)
+    assert all(field.digest_id == field.digest_id.upper() for field in page.fields)
+    assert all(len(field.digest_id) >= 25 for field in page.fields)
+    # digests are unique
+    assert len(page.fields) == len({field.digest_id for field in page.fields})
+    assert page.fields[0] != page.fields[1]
+    assert page.fields[0] == page.fields[0]
+
+
+def test_thumbnail_png(pdf):
+    png = pdf.page(0).thumbnail_png()
+    assert png[:10] == b'\x89PNG\r\n\x1a\n\x00\x00'
+    image = Image.open(io.BytesIO(png))
+    assert (image.width, image.height) == (800, 1132)
+
+
+def test_fields_image_map(pdf):
+    image_map = pdf.page(0).fields_image_map()
+    assert len(list(re.findall('area', image_map))) == 53
+
+
+def test_field_set(pdf):
+    for field in pdf.page(0).fields:
+        if field.name == 'topmostSubform[0].Page1[0].Champ_de_texte1[0]':
+            field.set('coucou')
+        elif field.name == 'topmostSubform[0].Page1[0].Case_à_cocher1[0]':
+            field.set(True)
+    with io.BytesIO() as fd:
+        pdf.write(fd)
+        new_pdf = PDF(fd.getvalue())
+    new_page = new_pdf.page(0)
+    check = set()
+    for field in new_page.fields:
+        if field.name == 'topmostSubform[0].Page1[0].Champ_de_texte1[0]':
+            check.add(1)
+            assert field.value == 'coucou'
+        elif field.name == 'topmostSubform[0].Page1[0].Case_à_cocher1[0]':
+            check.add(2)
+            assert field.value is True
+        elif field.widget_type == 'checkbox':
+            assert field.value is False
+        elif field.widget_type == 'text':
+            assert field.value == ''
+        else:
+            raise NotImplementedError
+    assert check == {1, 2}

tests/test_utils_templates.py

@@ -0,0 +1,26 @@
+# passerelle - uniform access to multiple data sources and services
+# Copyright (C) 2023 Entr'ouvert
+#
+# This program is free software: you can redistribute it and/or modify it
+# under the terms of the GNU Affero General Public License as published
+# by the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from passerelle.utils.templates import evaluate_condition, evaluate_template
+
+
+def test_evaluate_condition():
+    assert evaluate_condition('x == 1', {'x': 1}) is True
+    assert evaluate_condition('x == 0', {'x': 1}) is False
+
+
+def test_evaluate_template():
+    assert evaluate_template('{% if foo %}bar{% endif %}', {'foo': True}) == 'bar'