hakyll-images 0.4.3 → 0.4.4

raw patch · 8 files changed

+117/−6 lines, 8 filesPVP ok

version bump matches the API change (PVP)

API changes (from Hackage documentation)

Files

• CHANGELOG.md +4/−0
• hakyll-images.cabal +5/−2
• library/Hakyll/Images.hs +4/−1
• library/Hakyll/Images/Common.hs +9/−2
• library/Hakyll/Images/Metadata.hs +45/−0
• package.yaml +1/−1
• tests/Hakyll/Images/Metadata/Tests.hs +47/−0
• tests/TestSuite.hs +2/−0

@@ -1,5 +1,9 @@ # Change log
 
+## Release 0.4.4
+
+* Added the `imageMetadata` compiler, to extract metadata from images.
+
 ## Release 0.4.3
 
 * hakyll-images now handles file extensions in a case-insensitive manner (extension of PR #4).

@@ -4,10 +4,10 @@ -- -- see: https://github.com/sol/hpack ----- hash: ff6ba07ab7468ad9c999ec58ffab35f8ef4fafb3fe2d4788536a60ef35035d8c+-- hash: b8546296308b75bbf655dd856a069155995bfa86cef044e6b1366acc46a813aa  name:           hakyll-images-version:        0.4.3+version:        0.4.4 synopsis:       Hakyll utilities to work with images description:    hakyll-images is an add-on to the hakyll package. It adds utilities to work with images, including JPEG compression. category:       Web@@ -38,6 +38,7 @@       Hakyll.Images.Resize   other-modules:       Hakyll.Images.Common+      Hakyll.Images.Metadata       Paths_hakyll_images   hs-source-dirs:       library@@ -57,10 +58,12 @@   other-modules:       Hakyll.Images.Common.Tests       Hakyll.Images.CompressJpg.Tests+      Hakyll.Images.Metadata.Tests       Hakyll.Images.Resize.Tests       Hakyll.Images       Hakyll.Images.Common       Hakyll.Images.CompressJpg+      Hakyll.Images.Metadata       Hakyll.Images.Resize       Paths_hakyll_images   hs-source-dirs:

@@ -57,6 +57,8 @@     -- Basic types and functions
       Image
     , loadImage
+    -- Handling metadata
+    , module Hakyll.Images.Metadata
     -- Jpg compression
     , JpgQuality
     , compressJpg
@@ -73,4 +75,5 @@ 
 import Hakyll.Images.CompressJpg
 import Hakyll.Images.Resize
-import Hakyll.Images.Common+import Hakyll.Images.Common
+import Hakyll.Images.Metadata

@@ -20,6 +20,7 @@ 
 import Prelude                          hiding (readFile)
 
+
 import Codec.Picture.Types              (DynamicImage)
 import Codec.Picture.Saving
 
@@ -34,6 +35,7 @@ import Hakyll.Core.Item                 (Item(..))
 import Hakyll.Core.Writable             (Writable(..))
 
+
 -- Supported (i.e. encodable) image formats
 data ImageFormat
     = Jpeg 
@@ -42,27 +44,30 @@     | Tiff
     deriving (Eq, Generic)
 
+
 -- Automatic derivation of Binary instances requires Generic
 instance Binary ImageFormat
 
--- Polymorphic type only to get an instance of functor.
--- Do not use this type.
+
 data Image = Image { format :: ImageFormat
                    , image :: ByteString
                    }
     deriving (Typeable)
 
+
 -- When writing to disk, we ignore the image format.
 -- Trusting users to route correctly.
 instance Writable Image where
     -- Write the bytestring content
     write fp item  = write fp (image <$> item)
 
+
 -- Binary instance looks similar to the binary instance for a Hakyll Item
 instance Binary Image where
     put (Image fmt content) = put fmt >> put content
     get                     = Image <$> get <*> get
 
+
 -- | Load an image from a file.
 -- This function can be combined with other compilers.
 --
@@ -78,6 +83,7 @@     fmt <- fromExt <$> getUnderlyingExtension
     return $ (Image fmt) <$> content
 
+
 -- | Translation between file extensions and image formats.
 -- It is important to keep track of image formats because Hakyll
 -- compilers provides raw bytestrings and filenames.
@@ -93,6 +99,7 @@         fromExt' ".tif"  = Tiff
         fromExt' ".tiff" = Tiff
         fromExt' ext'     = error $ "Unsupported format: " <> ext'
+
 
 -- Encode images based on file extension
 encode :: ImageFormat -> DynamicImage -> Image

@@ -0,0 +1,45 @@+
+{-|
+Module      : Hakyll.Images.Metadata
+Description : Handling image metadata
+Copyright   : (c) Laurent P René de Cotret, 2019
+License     : BSD3
+Maintainer  : laurent.decotret@outlook.com
+Stability   : unstable
+Portability : portable
+-}
+module Hakyll.Images.Metadata 
+    ( module Codec.Picture.Metadata
+    , imageMetadata
+    , metadata
+    ) where
+
+import Codec.Picture                    (decodeImageWithMetadata)
+import Codec.Picture.Metadata           
+
+import Hakyll.Core.Compiler             (Compiler)
+import Hakyll.Core.Item                 (Item, itemBody)
+
+import Hakyll.Images.Common             (Image(..))
+
+-- | Extract metadata from an image. This function will throw an 
+-- error in case of a problem.
+--
+-- This function is for testing purposes.
+metadata :: Image -> Metadatas
+metadata im = either error snd (decodeImageWithMetadata (image im))
+
+
+-- | Extract metadata from an image.
+--
+-- @
+-- match "*.jpg" $ do
+--     route idRoute
+--     compile $ do
+--         im <- loadImage
+--         meta <- imageMetadata
+--         doSomethingWithMetadata meta
+--         ...
+-- @
+imageMetadata :: Item Image -> Compiler Metadatas
+imageMetadata = return . metadata . itemBody

@@ -1,5 +1,5 @@ name: hakyll-images
-version: '0.4.3'
+version: '0.4.4'
 github: "LaurentRDC/hakyll-images"
 license: BSD3
 author: "Laurent P. René de Cotret"

@@ -0,0 +1,47 @@+{-# LANGUAGE OverloadedStrings #-}
+--------------------------------------------------------------------------------
+module Hakyll.Images.Metadata.Tests
+    ( tests
+    ) where
+
+
+--------------------------------------------------------------------------------
+import           Test.Tasty             (TestTree, testGroup)
+import           Test.Tasty.HUnit       (Assertion, assertBool, testCase)
+
+
+--------------------------------------------------------------------------------
+import qualified Data.ByteString        as B
+import           Data.Maybe             (fromMaybe)
+import           Hakyll.Images
+import           Hakyll.Images.Common
+
+import qualified Hakyll.Images.Metadata as M
+
+import           Text.Printf            (printf)
+
+fromAssertions :: String       -- ^ Name
+               -> [Assertion]  -- ^ Cases
+               -> [TestTree]   -- ^ Result tests
+fromAssertions name =
+    zipWith testCase [printf "[%2d] %s" n name | n <- [1 :: Int ..]]
+
+testJpg :: IO Image 
+testJpg = Image Jpeg <$> (B.readFile "tests/data/piccolo.jpg")
+
+testMetadata :: Assertion
+testMetadata = do
+    im <- testJpg
+    let meta = metadata im
+        height = fromMaybe 0 (M.lookup M.Height meta)
+        width  = fromMaybe 0 (M.lookup M.Width meta)
+    
+    -- The following values of (width, height) = (1170, 647) are 
+    -- specific to the "piccolo.jpg" image
+    assertBool "Metadata was not decoded properly" (height == 647)
+    assertBool "Metadata was not decoded properly" (width == 1170)
+
+tests :: TestTree
+tests = testGroup "Hakyll.Images.Metadata.Tests" $ concat
+   [ fromAssertions "metadata" [ testMetadata ]
+   ]

@@ -13,6 +13,7 @@ import qualified Hakyll.Images.Common.Tests
 import qualified Hakyll.Images.CompressJpg.Tests
 import qualified Hakyll.Images.Resize.Tests
+import qualified Hakyll.Images.Metadata.Tests
 
 
 --------------------------------------------------------------------------------
@@ -21,4 +22,5 @@     [ Hakyll.Images.Common.Tests.tests
     , Hakyll.Images.CompressJpg.Tests.tests
     , Hakyll.Images.Resize.Tests.tests 
+    , Hakyll.Images.Metadata.Tests.tests
     ]