refactor(Transcript): render via Jinja template

- TODO(pairing): how best to make Item types available to Jinja?
- TODO(pairing): consider location of Jinja Environment object and template path
- TODO(pairing): reconsider test scope
- TODO(research): localization

securedrop_client/conversation/transcript/items/file.py

@@ -7,16 +7,10 @@
 
 
 class File(Item):
+    type = "file"
+
     def __init__(self, record: database.File):
         super().__init__()
 
         self.filename = record.filename
         self.sender = record.source.journalist_designation
-
-    @property
-    def context(self) -> Optional[str]:
-        return _("{username} sent:\n").format(username=self.sender)
-
-    @property
-    def transcript(self) -> str:
-        return _("File: {filename}\n").format(filename=self.filename)

securedrop_client/conversation/transcript/items/item.py

@@ -2,12 +2,4 @@
 
 
 class Item:
-    @property
-    def transcript(self) -> str:
-        """A transcription of the conversation item."""
-        raise NotImplementedError  # pragma: nocover
-
-    @property
-    def context(self) -> Optional[str]:
-        """Some context about the conversation item."""
-        raise NotImplementedError  # pragma: nocover
+    type = None

securedrop_client/conversation/transcript/items/message.py

@@ -7,6 +7,8 @@
 
 
 class Message(Item):
+    type = "message"
+
     def __init__(self, record: Union[database.Message, database.Reply]):
         super().__init__()
 
@@ -16,11 +18,3 @@ def __init__(self, record: Union[database.Message, database.Reply]):
             self.sender = record.source.journalist_designation
         else:
             self.sender = record.journalist.username
-
-    @property
-    def context(self) -> Optional[str]:
-        return _("{username} wrote:\n").format(username=self.sender)
-
-    @property
-    def transcript(self) -> str:
-        return self.content + "\n"

securedrop_client/conversation/transcript/transcript.py

@@ -1,3 +1,4 @@
+from jinja2 import Environment, PackageLoader, select_autoescape
 from typing import List, Optional
 
 from securedrop_client import db as database
@@ -6,39 +7,23 @@
 from .items import transcribe as transcribe_item
 
 
-def transcribe(record: database.Base) -> Optional[Item]:
-    return transcribe_item(record)
+env = Environment(
+    loader=PackageLoader("securedrop_client"),
+    autoescape=select_autoescape(),
+    # Since our plain-text templates have literal whitespace:
+    lstrip_blocks=True,
+    trim_blocks=True,
+)
 
 
-_ENTRY_SEPARATOR = "------\n"
+def transcribe(record: database.Base) -> Optional[Item]:
+    return transcribe_item(record)
 
 
 class Transcript:
     def __init__(self, conversation: database.Source) -> None:
-
         self._items = [transcribe(record) for record in conversation.collection]
+        self._template = env.get_template("transcript.txt")
 
     def __str__(self) -> str:
-        if len(self._items) <= 0:
-            return "No messages."
-
-        entries: List[str] = []
-
-        context: Optional[str] = None
-
-        for item in self._items:
-            if item is None:
-                continue
-
-            if context is not None and context == item.context:
-                entry = item.transcript
-            elif item.context is None:
-                entry = item.transcript  # pragma: nocover
-            else:
-                entry = f"{item.context}{item.transcript}"
-
-            entries.append(entry)
-
-            context = item.context
-
-        return _ENTRY_SEPARATOR.join(entries)
+        return self._template.render(items=self._items)

securedrop_client/locale/messages.pot

@@ -59,15 +59,6 @@ msgstr ""
 msgid "Failed to delete source at server"
 msgstr ""
 
-msgid "{username} sent:\n"
-msgstr ""
-
-msgid "File: {filename}\n"
-msgstr ""
-
-msgid "{username} wrote:\n"
-msgstr ""
-
 msgid "Download All Files"
 msgstr ""
 

securedrop_client/templates/transcript.txt

@@ -0,0 +1,16 @@
+{% if items|length <= 0 %}No messages.{% else %}
+  {% for item in items %}
+    {% if item.type == "message" %}
+      {% if loop.changed(item.sender) %}
+{{ item.sender }} wrote:
+      {% endif %}
+{{ item.content }}
+    {% elif item.type == "file" %}
+{{ item.sender }} sent:
+File: {{ item.filename }}
+    {% endif %}
+    {% if item.type is defined and not loop.last %}
+------
+    {% endif %}
+  {% endfor %}
+{% endif %}