Implement trivial functionality for image source endpoint

kodak/database/_shared.py

@@ -31,6 +31,17 @@ class Checksum(NamedTuple):
         """Construct from a hashlib object"""
         return cls(algorithm=data.name, digest=data.hexdigest())
 
+    def as_header(self) -> str:
+        """Format the checksum for the Content-Digest HTTP header"""
+        if self.algorithm.startswith("sha"):
+            alg = f"sha-{self.algorithm[3:]}"
+        elif self.algorithm.startswith("id"):
+            alg = f"id-sha-{self.algorithm[3:]}"
+        else:
+            alg = self.algorithm
+
+        return f"{alg}={self.digest}"
+
 
 class EnumField(peewee.CharField):
     """Custom field for storing enums"""

kodak/database/image.py

@@ -38,7 +38,7 @@ class ImageRecord(KodakModel):
         hasher = hashlib.sha256()
         view = memoryview(bytearray(1024 * 1024))
         with path.open("rb", buffering=0) as infile:
-            for chunk in iter(lambda: infile.readinto(view), 0):
+            for chunk in iter(lambda: infile.readinto(view), 0):  # type: ignore
                 hasher.update(view[:chunk])
 
         name = path.stem

kodak/resources/image.py

@@ -1,3 +1,8 @@
+import datetime
+
+import flask
+
+from kodak import database
 from kodak.resources._shared import authenticated
 from kodak.resources._shared import KodakResource
 from kodak.resources._shared import ResponseTuple
@@ -9,9 +14,20 @@ class Image(KodakResource):
     routes = ("/image/<string:image_name>",)
 
     @authenticated
-    def get(self, image_name: str) -> ResponseTuple:
+    def get(self, image_name: str) -> flask.Response:  # pylint: disable=no-self-use
         """Retrieve an original source image"""
-        raise NotImplementedError
+        with database.interface.atomic():
+            image = database.ImageRecord.get(database.ImageRecord.name == image_name)
+
+        resp = flask.send_file(
+            image.source,
+            cache_timeout=int(datetime.timedelta(days=365).total_seconds()),
+            add_etags=False,
+        )
+
+        resp.headers["Content-Digest"] = image.checksum.as_header()
+
+        return resp
 
     def head(self, image_name: str) -> ResponseTuple:
         """Alias HEAD to GET"""

kodak/tools/index.py

@@ -127,12 +127,12 @@ def build(config: Optional[configuration.KodakConfig] = None) -> None:
 
     with database.interface.atomic():
         for image in database.ImageRecord.select().where(
-            database.ImageRecord.deleted
+            database.ImageRecord.deleted  # pylint: disable=singleton-comparison
-            == False  # pylint: disable=singleton-comparison
+            == False
         ):
             if config.expose_source:
                 logger.debug(f"Creating source link to {image.source}")
                 image.create_link(config)
             else:
                 logger.debug(f"Removing source link to {image.source}")
-                image.delete_link(config)
+                image.remove_link(config)