asset_store.rb in documentcloud-cloud-crowd-0.0.6

- old
+ new
@@ -7,64 +7,93 @@
   # it may be the filesystem.
   #
   # You shouldn't need to use the AssetStore directly -- Action's +download+
   # and +save+ methods use it behind the scenes.
   class AssetStore
-    include FileUtils
     
-    # Creating an AssetStore will determine wether to save private or public
-    # files on S3, depending on the value of <tt>use_s3_authentication</tt> in 
-    # <tt>config.yml</tt>.
+    LOCAL_STORAGE_PATH = '/tmp/cloud_crowd_storage'
+    
+    # Creating an AssetStore mixes in the specific storage implementation 
+    # specified by 'storage' in <tt>config.yml</tt>.
     def initialize
       @use_auth = CloudCrowd.config[:use_s3_authentication]
-      mkdir_p temp_storage_path unless File.exists? temp_storage_path
+      @storage  = CloudCrowd.config[:storage]
+      FileUtils.mkdir_p temp_storage_path unless File.exists? temp_storage_path
+      case @storage
+      when 's3'         then extend S3Store
+      when 'filesystem' then extend FilesystemStore
+      else raise StorageNotFound, "#{@storage} is not a valid storage back end"
+      end
     end
     
     # Get the path to CloudCrowd's temporary local storage. All actions run
     # in subdirectories of this.
     def temp_storage_path
       "#{Dir.tmpdir}/cloud_crowd_tmp"
     end
     
-    # Copy a finished file from our local storage to S3. Save it publicly unless
-    # we're configured to use S3 authentication.
-    def save(local_path, save_path)
-      ensure_s3_connection
-      permission = @use_auth ? 'private' : 'public-read'
-      @bucket.put(save_path, File.open(local_path), {}, permission)
-    end
     
-    # Cleanup all S3 files for a job that's been completed and retrieved.
-    def cleanup_job(job)
-      ensure_s3_connection
-      @bucket.delete_folder("#{job.action}/job_#{job.id}")
+    # The S3Store is an implementation of an AssetStore that uses a bucket
+    # on S3 for all resulting files.
+    module S3Store
+      
+      # Save a finished file from local storage to S3. Save it publicly unless 
+      # we're configured to use S3 authentication.
+      def save(local_path, save_path)
+        ensure_s3_connection
+        permission = @use_auth ? 'private' : 'public-read'
+        @bucket.put(save_path, File.open(local_path), {}, permission)
+      end
+      
+      # Return the S3 public URL for a finshed file. Authenticated links expire
+      # after one day by default.
+      def url(save_path)
+        @use_auth ? @s3.interface.get_link(@bucket, save_path) :
+                    @bucket.key(save_path).public_link
+      end
+      
+      # Remove all of a Job's resulting files from S3, both intermediate and finished.
+      def cleanup_job(job)
+        ensure_s3_connection
+        @bucket.delete_folder("#{job.action}/job_#{job.id}")
+      end
+      
+      # Workers, through the course of many WorkUnits, keep around an AssetStore.
+      # Ensure we have a persistent S3 connection after first use.
+      def ensure_s3_connection
+        unless @s3 && @bucket
+          params = {:port => 80, :protocol => 'http'}
+          @s3 = RightAws::S3.new(CloudCrowd.config[:aws_access_key], CloudCrowd.config[:aws_secret_key], params)
+          @bucket = @s3.bucket(CloudCrowd.config[:s3_bucket], true)
+        end
+      end
     end
     
-    # Return the S3 public URL for a finshed file. Authenticated links expire
-    # after one day by default.
-    def url(save_path)
-      @use_auth ? @s3.interface.get_link(@bucket, save_path) :
-                  @bucket.key(save_path).public_link
-    end
     
-    private
-    
-    # Unused for the moment. Think about using the filesystem instead of S3
-    # in development.
-    def save_to_filesystem(local_path, save_path)
-      save_path = File.join("/tmp/cloud_crowd_storage", save_path)
-      save_dir = File.dirname(save_path)
-      mkdir_p save_dir unless File.exists? save_dir
-      cp(local_path, save_path)
-    end
-    
-    # Workers, through the course of many WorkUnits, keep around an AssetStore.
-    # Ensure we have a persistent S3 connection after first use.
-    def ensure_s3_connection
-      unless @s3 && @bucket
-        params = {:port => 80, :protocol => 'http'}
-        @s3 = RightAws::S3.new(CloudCrowd.config[:aws_access_key], CloudCrowd.config[:aws_secret_key], params)
-        @bucket = @s3.bucket(CloudCrowd.config[:s3_bucket], true)
+    # The FilesystemStore is an implementation of the AssetStore, good only for
+    # use in development, testing, or if you're only running a single-machine
+    # installation.
+    module FilesystemStore
+      
+      # Save a file to somewhere semi-persistent on the filesystem. Can be used
+      # in development, when offline, or if you happen to have a single-machine
+      # CloudCrowd installation. To use, configure :local_storage.
+      def save(local_path, save_path)
+        save_path = File.join(LOCAL_STORAGE_PATH, save_path)
+        save_dir = File.dirname(save_path)
+        FileUtils.mkdir_p save_dir unless File.exists? save_dir
+        FileUtils.cp(local_path, save_path)
+      end
+      
+      # Return the URL for a file saved to the local filesystem.
+      def url(save_path)
+        "file://#{File.expand_path(File.join(LOCAL_STORAGE_PATH, save_path))}"
+      end
+      
+      # Remove all of a Job's result files from the filesystem.
+      def cleanup_job(job)
+        path = "#{LOCAL_STORAGE_PATH}/#{job.action}/job_#{job.id}"
+        FileUtils.rm_r(path) if File.exists?(path)
       end
     end
   
   end
 
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