Make the default provider just assume the URL is a direct file link

lib/picopackage/cli.rb

@@ -95,7 +95,7 @@ module Picopackage
         file = argv.first
         source_file = SourceFile.from_file(file)
         begin
-          Fetch.fetch(source_file.url, path, force: options[:force])
+          Fetch.fetch(source_file.url, File.dirname(file), force: options[:force])
         rescue LocalModificationError => e
           puts "Error: #{e.message}"
         rescue => e

lib/picopackage/provider.rb

@@ -39,11 +39,9 @@ module Picopackage
       @content = nil
     end
 
-    def transform_url(url) = url
-
     def body = @body ||= fetch
-
     def json_body = @json_body ||= JSON.parse(body)
+    def transform_url(url) = url
 
     def fetch
       begin
@@ -67,52 +65,43 @@ module Picopackage
 
     def handles_body?
       true
-    rescue FileTooLargeError
+    rescue FileTooLargeError, Net::HTTPError, RuntimeError => e
       false
     end
 
-    def content
-      # Implement in subclass - this come from the `body`. 
-      # Spliting content into code and metadata is the job of the SourceFile class
+    # Implement in subclass - this come from the `body`. 
+    # Spliting content into code and metadata is the job of the SourceFile class
+    def content = body
 
-      raise NotImplementedError
-    end
-
-    def filename
-      # Implement in subclass - this should return the filename extracted from the body - if it exists, but not from the metadata
-      raise NotImplementedError
-    end
+    # Implement in subclass - this should return the filename extracted from the body - if it exists, but not from the metadata
+    def filename = File.basename @url
 
     def source_file
-      @source_file ||= SourceFile.from_content(
-        content, metadata: {'filename' => filename, 'url' => url, 'version' => '0.0.1'}
-      )
+      @source_file ||= SourceFile.from_content(content, metadata: {'filename' => filename, 'url' => url, 'version' => '0.0.1'})
     end
   end
 
   class GithubGistProvider < DefaultProvider
     def self.handles_url?(url) = url.match?(%r{gist\.github\.com})
-
+    def content = json_body["files"].values.first["content"]
+    def filename = json_body["files"].values.first["filename"]
     def transform_url(url)
       gist_id = url[/gist\.github\.com\/[^\/]+\/([a-f0-9]+)/, 1]
       "https://api.github.com/gists/#{gist_id}"
     end
-
-    def content = json_body["files"].values.first["content"]
-
-    def filename = json_body["files"].values.first["filename"]
   end
 
   class OpenGistProvider < DefaultProvider
-    def handles_url?(url)
-      :maybe
-    end
-
+    def handles_url?(url) = :maybe
     def transform_url(url) = "#{url}.json"
-
     def content = json_body.dig("files",0, "content")
-
     def filename = json_body.dig("files",0, "filename")
+    def handles_body?
+      content && filename
+    rescue FileTooLargeError, Net::HTTPError, RuntimeError => e
+      false
+    end
+    # If we successfully fetch the body, and the body contains content and a filename, then we can handle the body
   end
 
   PROVIDERS = [