Support moving files between uris

.gitignore

@@ -6,3 +6,4 @@ tmp/
 
 .bundle/
 .rspec_status
+.yardoc/

README.md

@@ -138,3 +138,9 @@ FileStorage.for("inmemory://bucket/path/").list
 FileStorage.for("inmemory://bucket/path/").delete!
 => true
 ```
+
+### Moving a file
+```ruby
+FileStorage.for("inmemory://bucket/path/file.xml").move!("inmemory://bucket/path/file2.xml")
+=> "inmemory://bucket/path/file2.xml"
+```

lib/file_storage.rb

@@ -178,6 +178,36 @@ def delete!
       true
     end
 
+    # Moves the existing file to a new file path
+    #
+    # @param [String] new_key The new key to move the file to
+    # @return [String] A URI to the file's new path
+    # @example Move a file
+    #   FileStorage.for("inmemory://bucket1/foo").move!("inmemory://bucket2/bar")
+    def move!(new_key)
+      raise ArgumentError, "Key cannot be empty" if key.empty?
+
+      new_key_ctx = FileStorage.for(new_key)
+
+      raise ArgumentError, "Destination key cannot be empty" if new_key_ctx.key.empty?
+
+      info("Moving file", new_key: new_key, event: "move")
+
+      start = FileStorage::Timing.monotonic_now
+      result = adapter.move!(
+        bucket: bucket,
+        key: key,
+        new_bucket: new_key_ctx.bucket,
+        new_key: new_key_ctx.key,
+      )
+
+      info("Moved file",
+           event: "move_finished",
+           duration: FileStorage::Timing.monotonic_now - start)
+
+      "#{adapter_type}://#{result[:bucket]}/#{result[:key]}"
+    end
+
     private
 
     attr_reader :adapter

lib/file_storage/disk.rb

@@ -53,6 +53,15 @@ def delete!(bucket:, key:)
       true
     end
 
+    def move!(bucket:, key:, new_bucket:, new_key:)
+      FileUtils.mv(key_path(bucket, key), key_path(new_bucket, new_key))
+
+      {
+        bucket: new_bucket,
+        key: new_key,
+      }
+    end
+
     private
 
     attr_reader :base_dir

lib/file_storage/gcs.rb

@@ -56,6 +56,18 @@ def delete!(bucket:, key:)
       true
     end
 
+    def move!(bucket:, key:, new_bucket:, new_key:)
+      old_file = get_bucket(bucket).file(key)
+      destination_bucket = get_bucket(new_bucket)
+      file.copy(destination_bucket.name, new_key)
+      old_file.delete
+
+      {
+        bucket: new_bucket,
+        key: new_key,
+      }
+    end
+
     private
 
     attr_reader :storage

lib/file_storage/in_memory.rb

@@ -54,5 +54,13 @@ def delete!(bucket:, key:)
 
       true
     end
+
+    def move!(bucket:, key:, new_bucket:, new_key:)
+      @buckets[new_bucket][new_key] = @buckets.fetch(bucket).delete(key)
+      {
+        bucket: new_bucket,
+        key: new_key,
+      }
+    end
   end
 end

spec/file_storage/disk_spec.rb

@@ -141,4 +141,44 @@
         to raise_error(Errno::ENOENT, /No such file or directory/)
     end
   end
+
+  describe "#move!" do
+    subject(:move) do
+      instance.move!(bucket: bucket, key: key, new_bucket: new_bucket, new_key: new_key)
+    end
+
+    let(:new_bucket) { "cake" }
+
+    context "when the 'existing' file doesn't exist" do
+      let(:key) { "foobar" }
+      let(:new_key) { "barbaz" }
+
+      it "raises a File error" do
+        expect { move }.to raise_error(Errno::ENOENT, /No such file or directory/)
+      end
+    end
+
+    context "when the file does exist" do
+      let(:key) { "2021-02-08/hello1" }
+      let(:new_key) { "2021-02-08/hello2" }
+      let(:content) { "world" }
+
+      before { instance.upload!(bucket: bucket, key: key, content: content) }
+
+      it "moves the file" do
+        move
+
+        expect(instance.download(bucket: new_bucket, key: new_key)[:content]).to eq(content)
+        expect { instance.download(bucket: bucket, key: key)[:content] }.
+          to raise_error(Errno::ENOENT, /No such file or directory/)
+      end
+
+      it "returns the expected payload" do
+        expect(move).to eq(
+          bucket: new_bucket,
+          key: new_key,
+        )
+      end
+    end
+  end
 end

spec/file_storage/in_memory_spec.rb

@@ -104,6 +104,46 @@
     end
   end
 
+  describe "#move!" do
+    subject(:move) do
+      instance.move!(bucket: bucket, key: key, new_bucket: new_bucket, new_key: new_key)
+    end
+
+    let(:new_bucket) { "cake" }
+
+    context "when the 'existing' file doesn't exist" do
+      let(:key) { "foobar" }
+      let(:new_key) { "barbaz" }
+
+      it "raises a KeyError" do
+        expect { move }.to raise_error(KeyError, /#{bucket}/)
+      end
+    end
+
+    context "when the file does exist" do
+      let(:key) { "2021-02-08/hello1" }
+      let(:new_key) { "2021-02-08/hello2" }
+      let(:content) { "world" }
+
+      before { instance.upload!(bucket: bucket, key: key, content: content) }
+
+      it "moves the file" do
+        move
+
+        expect(instance.download(bucket: new_bucket, key: new_key)[:content]).to eq(content)
+        expect { instance.download(bucket: bucket, key: key)[:content] }.
+          to raise_error(KeyError, /key not found/)
+      end
+
+      it "returns the expected payload" do
+        expect(move).to eq(
+          bucket: new_bucket,
+          key: new_key,
+        )
+      end
+    end
+  end
+
   describe "#reset!" do
     let(:bucket2) { "bucket2" }
 

spec/file_storage_spec.rb

@@ -153,5 +153,24 @@
         expect(described_class.for("inmemory://bucket/file1").delete!).to eq(true)
       end
     end
+
+    describe "#move!" do
+      subject(:move) { described_class.for(old_key).move!(new_key) }
+
+      let(:old_key) { "inmemory://bucket/file1" }
+      let(:new_key) { "inmemory://bucket2/file2" }
+
+      before { described_class.for(old_key).upload!("hello") }
+
+      it "returns the new path's uri" do
+        expect(move).to eq(new_key)
+      end
+
+      it "moves the file" do
+        move
+
+        expect(described_class.for(new_key).download[:content]).to eq("hello")
+      end
+    end
   end
 end