[FIX] report_py3o: Add missing method _merge_pdf.

This method was previously provided by Odoo and is used to merge all the reports generated if the generation is called for more than one record

report_py3o/__manifest__.py

@@ -14,7 +14,8 @@
     'depends': ['web'],
     'external_dependencies': {
         'python': ['py3o.template',
-                   'py3o.formats']
+                   'py3o.formats',
+                   'PyPDF2']
     },
     'data': [
         'security/ir.model.access.csv',

report_py3o/models/py3o_report.py

@@ -28,7 +28,10 @@ try:
     from py3o.formats import Formats, UnkownFormatException
 except ImportError:
     logger.debug('Cannot import py3o.formats')
-
+try:
+    from PyPDF2 import PdfFileWriter, PdfFileReader
+except ImportError:
+    logger.debug('Cannot import PyPDF2')
 
 _extender_functions = {}
 
@@ -302,6 +305,23 @@ class Py3oReport(models.TransientModel):
                 cpt += 1
         return result_path
 
+    @api.model
+    def _merge_pdf(self, reports_path):
+        """ Merge PDF files into one.
+
+        :param reports_path: list of path of pdf files
+        :returns: path of the merged pdf
+        """
+        writer = PdfFileWriter()
+        for path in reports_path:
+            reader = PdfFileReader(path)
+            writer.appendPagesFromReader(reader)
+        merged_file_fd, merged_file_path = tempfile.mkstemp(
+            suffix='.pdf', prefix='report.merged.tmp.')
+        with closing(os.fdopen(merged_file_fd, 'wb')) as merged_file:
+            writer.write(merged_file)
+        return merged_file_path
+
     @api.multi
     def _merge_results(self, reports_path):
         self.ensure_one()

report_py3o/tests/test_report_py3o.py

@@ -18,6 +18,8 @@ from odoo.addons.base.tests.test_mimetypes import PNG
 from ..models.py3o_report import TemplateNotFound
 from ..models._py3o_parser_context import format_multiline_value
 from base64 import b64encode
+from PyPDF2 import PdfFileWriter
+from PyPDF2.pdf import PageObject
 import logging
 
 logger = logging.getLogger(__name__)
@@ -79,7 +81,30 @@ class TestReportPy3o(TransactionCase):
     def test_reports(self):
         res = self.report.render(self.env.user.ids)
         self.assertTrue(res)
-        self.report.py3o_filetype = 'pdf'
+
+    def test_reports_merge_zip(self):
+        users = self.env['res.users'].search([])
+        self.assertTrue(len(users) > 0)
+        py3o_report = self.env['py3o.report']
+        _zip_results = self.py3o_report._zip_results
+        with mock.patch.object(
+                py3o_report.__class__, '_zip_results') as patched_zip_results:
+            patched_zip_results.side_effect = _zip_results
+            content, filetype = self.report.render(users.ids)
+            self.assertEqual(1, patched_zip_results.call_count)
+            self.assertEqual(filetype, 'zip')
+
+    def test_reports_merge_pdf(self):
+        reports_path = []
+        for i in range(0, 3):
+            result = tempfile.mktemp('.txt')
+            writer = PdfFileWriter()
+            writer.addPage(PageObject.createBlankPage(width=100, height=100))
+            with open(result, 'wb') as fp:
+                writer.write(fp)
+            reports_path.append(result)
+        res = self.py3o_report._merge_pdf(reports_path)
+        self.assertTrue(res)
 
     def test_report_load_from_attachment(self):
         self.report.write({"attachment_use": True,