feat(stream): implement stream processing service with routes for managing streaming URLs; add support for concurrent processing and metadata extraction

app/models/stream.py

@@ -4,7 +4,7 @@ from datetime import datetime
 from typing import TYPE_CHECKING, Optional
 from zoneinfo import ZoneInfo
 
-from sqlalchemy import DateTime, ForeignKey, Integer, String, Text
+from sqlalchemy import DateTime, ForeignKey, Integer, String, Text, UniqueConstraint
 from sqlalchemy.orm import Mapped, mapped_column, relationship
 
 from app.database import db
@@ -33,6 +33,7 @@ class Stream(db.Model):
     status: Mapped[str] = mapped_column(
         String(50), nullable=False, default="pending"
     )
+    error: Mapped[str | None] = mapped_column(Text, nullable=True)
     created_at: Mapped[datetime] = mapped_column(
         DateTime,
         default=lambda: datetime.now(tz=ZoneInfo("UTC")),
@@ -48,6 +49,13 @@ class Stream(db.Model):
     # Relationships
     sound: Mapped["Sound"] = relationship("Sound", back_populates="streams")
 
+    # Constraints
+    __table_args__ = (
+        UniqueConstraint(
+            "service", "service_id", name="unique_service_stream"
+        ),
+    )
+
     def __repr__(self) -> str:
         """String representation of the stream."""
         return f"<Stream(id={self.id}, service='{self.service}', service_id='{self.service_id}', sound_id={self.sound_id})>"
@@ -66,6 +74,7 @@ class Stream(db.Model):
             "album": self.album,
             "genre": self.genre,
             "status": self.status,
+            "error": self.error,
             "created_at": (
                 self.created_at.isoformat() if self.created_at else None
             ),