Added support for chunked uploads. (#1208)

* Added tests for mid-size and big artifacts, reproducing a problem with chunked uploads.

* Added support for chunked uploads.

* Enforced overwriting uploaded artifacts on receiving the first chunk.

Co-authored-by: Casey Lee <cplee@nektos.com>

pkg/artifacts/server.go

@@ -49,6 +49,7 @@ type MkdirFS interface {
 	fs.FS
 	MkdirAll(path string, perm fs.FileMode) error
 	Open(name string) (fs.File, error)
+	OpenAtEnd(name string) (fs.File, error)
 }
 
 type MkdirFsImpl struct {
@@ -61,7 +62,22 @@ func (fsys MkdirFsImpl) MkdirAll(path string, perm fs.FileMode) error {
 }
 
 func (fsys MkdirFsImpl) Open(name string) (fs.File, error) {
-	return os.OpenFile(fsys.dir+"/"+name, os.O_CREATE|os.O_RDWR, 0644)
+	return os.OpenFile(fsys.dir+"/"+name, os.O_CREATE|os.O_RDWR|os.O_TRUNC, 0644)
+}
+
+func (fsys MkdirFsImpl) OpenAtEnd(name string) (fs.File, error) {
+	file, err := os.OpenFile(fsys.dir+"/"+name, os.O_CREATE|os.O_RDWR, 0644)
+
+	if err != nil {
+		return nil, err
+	}
+
+	_, err = file.Seek(0, os.SEEK_END)
+	if err != nil {
+		return nil, err
+	}
+
+	return file, nil
 }
 
 var gzipExtension = ".gz__"
@@ -98,7 +114,14 @@ func uploads(router *httprouter.Router, fsys MkdirFS) {
 			panic(err)
 		}
 
-		file, err := fsys.Open(filePath)
+		file, err := func() (fs.File, error) {
+			contentRange := req.Header.Get("Content-Range")
+			if contentRange != "" && !strings.HasPrefix(contentRange, "bytes 0-") {
+				return fsys.OpenAtEnd(filePath)
+			}
+			return fsys.Open(filePath)
+		}()
+
 		if err != nil {
 			panic(err)
 		}

pkg/artifacts/server_test.go

@@ -51,6 +51,16 @@ func (fsys MapFsImpl) Open(path string) (fs.File, error) {
 	return WritableFile{result, fsys.MapFS, path}, err
 }
 
+func (fsys MapFsImpl) OpenAtEnd(path string) (fs.File, error) {
+	var file = fstest.MapFile{
+		Data: []byte("content2"),
+	}
+	fsys.MapFS[path] = &file
+
+	result, err := fsys.MapFS.Open(path)
+	return WritableFile{result, fsys.MapFS, path}, err
+}
+
 func TestNewArtifactUploadPrepare(t *testing.T) {
 	assert := assert.New(t)
 

pkg/artifacts/testdata/upload-and-download/artifacts.yml

@@ -26,10 +26,17 @@ jobs:
         run: |
           mkdir -p path/to/dir-1
           mkdir -p path/to/dir-2
-          mkdir -p path/to/dir-3    
+          mkdir -p path/to/dir-3
+          mkdir -p path/to/dir-5
+          mkdir -p path/to/dir-6
+          mkdir -p path/to/dir-7
           echo "Lorem ipsum dolor sit amet" > path/to/dir-1/file1.txt
           echo "Hello world from file #2" > path/to/dir-2/file2.txt
           echo "This is a going to be a test for a large enough file that should get compressed with GZip. The @actions/artifact package uses GZip to upload files. This text should have a compression ratio greater than 100% so it should get uploaded using GZip" > path/to/dir-3/gzip.txt
+          dd if=/dev/random of=path/to/dir-5/file5.rnd bs=1024 count=1024
+          dd if=/dev/random of=path/to/dir-6/file6.rnd bs=1024 count=$((10*1024))
+          dd if=/dev/random of=path/to/dir-7/file7.rnd bs=1024 count=$((10*1024))
+
       # Upload a single file artifact
       - name: 'Upload artifact #1'
         uses: actions/upload-artifact@v2
@@ -59,6 +66,35 @@ jobs:
             path/to/dir-1/*
             path/to/dir-[23]/*
             !path/to/dir-3/*.txt
+      
+      # Upload a mid-size file artifact
+      - name: 'Upload artifact #5'
+        uses: actions/upload-artifact@v2
+        with:
+          name: 'Mid-Size-Artifact'
+          path: path/to/dir-5/file5.rnd
+      
+      # Upload a big file artifact
+      - name: 'Upload artifact #6'
+        uses: actions/upload-artifact@v2
+        with:
+          name: 'Big-Artifact'
+          path: path/to/dir-6/file6.rnd
+
+      # Upload a big file artifact twice
+      - name: 'Upload artifact #7 (First)'
+        uses: actions/upload-artifact@v2
+        with:
+          name: 'Big-Uploaded-Twice'
+          path: path/to/dir-7/file7.rnd
+
+      # Upload a big file artifact twice
+      - name: 'Upload artifact #7 (Second)'
+        uses: actions/upload-artifact@v2
+        with:
+          name: 'Big-Uploaded-Twice'
+          path: path/to/dir-7/file7.rnd
+
       # Verify artifacts. Switch to download-artifact@v2 once it's out of preview
       
       # Download Artifact #1 and verify the correctness of the content
@@ -138,3 +174,57 @@ jobs:
             echo "File contents of downloaded artifacts are incorrect"
             exit 1
           fi
+      
+      - name: 'Download artifact #5'
+        uses: actions/download-artifact@v2
+        with:
+          name: 'Mid-Size-Artifact'
+          path: mid-size/artifact/path
+      
+      - name: 'Verify Artifact #5'
+        run: |
+          file="mid-size/artifact/path/file5.rnd"
+          if [ ! -f $file ] ; then
+            echo "Expected file does not exist"
+            exit 1
+          fi
+          if ! diff $file path/to/dir-5/file5.rnd ; then
+            echo "File contents of downloaded artifact are incorrect"
+            exit 1
+          fi
+      
+      - name: 'Download artifact #6'
+        uses: actions/download-artifact@v2
+        with:
+          name: 'Big-Artifact'
+          path: big/artifact/path
+      
+      - name: 'Verify Artifact #6'
+        run: |
+          file="big/artifact/path/file6.rnd"
+          if [ ! -f $file ] ; then
+            echo "Expected file does not exist"
+            exit 1
+          fi
+          if ! diff $file path/to/dir-6/file6.rnd ; then
+            echo "File contents of downloaded artifact are incorrect"
+            exit 1
+          fi
+
+      - name: 'Download artifact #7'
+        uses: actions/download-artifact@v2
+        with:
+          name: 'Big-Uploaded-Twice'
+          path: big-uploaded-twice/artifact/path
+
+      - name: 'Verify Artifact #7'
+        run: |
+          file="big-uploaded-twice/artifact/path/file7.rnd"
+          if [ ! -f $file ] ; then
+            echo "Expected file does not exist"
+            exit 1
+          fi
+          if ! diff $file path/to/dir-7/file7.rnd ; then
+            echo "File contents of downloaded artifact are incorrect"
+            exit 1
+          fi