Make email template placeholders configurable via environment variables

scraibe/email_sender.py

@@ -4,6 +4,7 @@ Email sender module for ScrAIbe.
 Sends transcription outputs (TXT, JSON, etc.) via SMTP.
 All credentials are configured via environment variables.
 Supports both plain text and HTML email bodies.
+Template placeholders are primarily filled via environment variables.
 """
 
 import os
@@ -13,7 +14,7 @@ from email import encoders
 from email.mime.base import MIMEBase
 from email.mime.multipart import MIMEMultipart
 from email.mime.text import MIMEText
-from typing import List, Optional
+from typing import List, Optional, Dict, Any
 
 logger = logging.getLogger("scraibe.email_sender")
 
@@ -52,7 +53,31 @@ def get_email_config():
     }
 
 
-def load_template(template_name: str, **kwargs) -> str:
+def build_template_context(**runtime_kwargs: Any) -> Dict[str, Any]:
+    """
+    Build a context dict for templates from:
+      - environment variables (base, customizable)
+      - runtime-provided values (override env if present)
+
+    Environment variables:
+      - EMAIL_CONTACT_ADDRESS: value for {contact_email}
+      - EMAIL_CSS_PATH: value for {css_path}
+
+    Runtime kwargs are merged on top (e.g. queue_position, exception).
+    """
+    ctx: Dict[str, Any] = {
+        "contact_email": os.getenv("EMAIL_CONTACT_ADDRESS", "support@example.com"),
+        "css_path": os.getenv("EMAIL_CSS_PATH", ""),
+    }
+
+    # Runtime values override env if provided
+    if runtime_kwargs:
+        ctx.update(runtime_kwargs)
+
+    return ctx
+
+
+def load_template(template_name: str, **runtime_kwargs: Any) -> str:
     """
     Load an HTML email template from misc/ and render placeholders.
 
@@ -70,9 +95,12 @@ def load_template(template_name: str, **kwargs) -> str:
     with open(path, "r", encoding="utf-8") as f:
         template = f.read()
 
+    # Build context from env + runtime
+    ctx = build_template_context(**runtime_kwargs)
+
     # Replace {placeholder} style variables safely
     try:
-        return template.format(**kwargs)
+        return template.format(**ctx)
     except KeyError as e:
         raise EmailError(f"Missing template variable: {e}")
 

scraibe/tasks.py

@@ -15,9 +15,6 @@ from .email_sender import send_email, EmailError, load_template
 
 logger = logging.getLogger("scraibe.tasks")
 
-# Contact email used in templates; can be overridden via env
-CONTACT_EMAIL = os.getenv("EMAIL_CONTACT_ADDRESS", "support@example.com")
-
 
 def get_queue_position(task_id: str) -> int:
     """
@@ -42,6 +39,7 @@ def get_queue_position(task_id: str) -> int:
 def send_initial_email(to: str, queue_pos: int):
     """
     Send initial confirmation email with queue position using HTML template.
+    Static placeholders (contact_email, css_path) come from env via load_template.
     """
     subject = "ScrAIbe: Your transcription request has been received"
 
@@ -61,17 +59,16 @@ def send_initial_email(to: str, queue_pos: int):
         "You will receive an email with your transcript (and summary, if requested) "
         "once processing is complete.\n\n"
         "If you have any questions, contact us at "
-        f"{CONTACT_EMAIL}.\n\n"
+        f"{os.getenv('EMAIL_CONTACT_ADDRESS', 'support@example.com')}.\n\n"
         "This is an automated message from ScrAIbe.\n"
     )
 
-    # Build HTML using template
+    # Build HTML using template; only dynamic value is queue_position
     html = None
     try:
         html = load_template(
             "upload_notification_template.html",
             queue_position=str(queue_pos) if queue_pos > 0 else "the queue",
-            contact_email=CONTACT_EMAIL,
         )
     except EmailError as e:
         logger.warning("Failed to render upload notification template: %s", e)
@@ -92,6 +89,7 @@ def send_success_email(
 ):
     """
     Send final email with transcript and attachments using HTML template.
+    Static placeholders (contact_email, css_path) come from env via load_template.
     """
     subject = "ScrAIbe: Your transcript is ready"
 
@@ -114,16 +112,15 @@ def send_success_email(
         "\n"
         "Job ID: " + str(task_id) + "\n\n"
         "If you have any questions, contact us at "
-        f"{CONTACT_EMAIL}.\n\n"
+        f"{os.getenv('EMAIL_CONTACT_ADDRESS', 'support@example.com')}.\n\n"
         "This is an automated message from ScrAIbe.\n"
     )
 
-    # Build HTML using template
+    # Build HTML using template; no dynamic placeholders needed
     html = None
     try:
         html = load_template(
             "success_template.html",
-            contact_email=CONTACT_EMAIL,
         )
     except EmailError as e:
         logger.warning("Failed to render success template: %s", e)
@@ -144,6 +141,7 @@ def send_success_email(
 def send_error_email(to: str, error_message: str, task_id: str):
     """
     Send error notification email using HTML template.
+    Static placeholders (contact_email, css_path) come from env via load_template.
     """
     subject = "ScrAIbe: Error with your transcription request"
 
@@ -155,17 +153,16 @@ def send_error_email(to: str, error_message: str, task_id: str):
         "Job ID: " + str(task_id) + "\n\n"
         "Please contact your administrator if the problem persists.\n\n"
         "If you have any questions, contact us at "
-        f"{CONTACT_EMAIL}.\n\n"
+        f"{os.getenv('EMAIL_CONTACT_ADDRESS', 'support@example.com')}.\n\n"
         "This is an automated message from ScrAIbe.\n"
     )
 
-    # Build HTML using template
+    # Build HTML using template; only dynamic placeholder is exception
     html = None
     try:
         html = load_template(
             "error_notification_template.html",
             exception=str(error_message),
-            contact_email=CONTACT_EMAIL,
         )
     except EmailError as e:
         logger.warning("Failed to render error template: %s", e)