upload/aws: Add basic S3 upload test

The test is very simple, it just uploads object to S3, downloads it back and
compares them.

internal/upload/awsupload/awsupload_test.go

@@ -0,0 +1,155 @@
+package awsupload_test
+
+import (
+	"bytes"
+	"fmt"
+	"github.com/osbuild/osbuild-composer/internal/upload/awsupload"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path"
+	"testing"
+
+	"github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/aws/credentials"
+	"github.com/aws/aws-sdk-go/aws/session"
+	"github.com/aws/aws-sdk-go/service/s3"
+	"github.com/aws/aws-sdk-go/service/s3/s3manager"
+)
+
+func handleErrors(t *testing.T, err error) {
+	if err != nil {
+		t.Fatal(err)
+	}
+}
+
+func loadEnvVar(t *testing.T, envVarName string) (string, bool) {
+	variable, exists := os.LookupEnv(envVarName)
+	if !exists {
+		t.Logf("Environment variable does not exist: %s", envVarName)
+		return "", false
+	}
+	return variable, true
+}
+
+func generateRandomFile(pattern string, length int) (string, []byte, error) {
+	f, err := ioutil.TempFile("/tmp", pattern)
+	if err != nil {
+		return "", []byte{}, err
+	}
+	fileName := f.Name()
+
+	countArg := fmt.Sprintf("count=%d", length)
+	cmd := exec.Command("dd", "bs=1", countArg, "if=/dev/urandom", fmt.Sprintf("of=%s", fileName))
+	err = cmd.Run()
+
+	contents, err := ioutil.ReadAll(f)
+	if err != nil {
+		return "", []byte{}, err
+	}
+
+	if err := f.Close(); err != nil {
+		return ",", []byte{}, err
+	}
+
+	return fileName, contents, err
+}
+
+func loadTestSettings(t *testing.T) (string, string, string, string) {
+	accessKeyId, akExists := loadEnvVar(t, "AWS_ACCESS_KEY_ID")
+	secretAccessKey, sakExists := loadEnvVar(t, "AWS_SECRET_ACCESS_KEY")
+	region, regionExists := loadEnvVar(t, "AWS_REGION")
+	bucket, bucketExists := loadEnvVar(t, "AWS_BUCKET")
+
+	// Workaround Travis security feature. If non of the variables is set, just ignore the test
+	if !akExists && !sakExists && !bucketExists && !regionExists {
+		t.Skip("No AWS configuration provided, assuming that this is running in CI. Skipping the test.")
+	}
+	// If only one/two of them are not set, then fail
+	if !akExists || !sakExists || !bucketExists || !regionExists {
+		t.Fatal("You need to define all variables for AWS connection.")
+	}
+	return accessKeyId, secretAccessKey, region, bucket
+}
+
+func TestAWS_S3Upload(t *testing.T) {
+	// Load test settings
+	accessKeyId, secretAccessKey, region, bucket := loadTestSettings(t)
+
+	// There's no way to retrieve session from awsupload, therefore we need to create an extra one in tests
+	sess, err := createSession(accessKeyId, secretAccessKey, region)
+	handleErrors(t, err)
+
+	// Generate random file to be uploaded
+	fileLength := 512 * 512
+	filePath, content, err := generateRandomFile("osbuild-composer-test-aws-upload-", fileLength)
+	handleErrors(t, err)
+	defer os.Remove(filePath)
+
+	// Use filename as s3 key
+	s3Key := path.Base(filePath)
+
+	// Test uploader
+	awsUpload, err := awsupload.New(region, accessKeyId, secretAccessKey)
+	if err != nil {
+		t.Fatalf("obtaining session failed: %s", err.Error())
+	}
+	handleErrors(t, err)
+
+	_, err = awsUpload.Upload(filePath, bucket, s3Key)
+
+	if err != nil {
+		t.Fatalf("upload failed: %s", err.Error())
+	}
+
+	// Delete the object from S3 after the test is finished
+	defer func() {
+		s := s3.New(sess)
+		s.DeleteObject(&s3.DeleteObjectInput{
+			Bucket: &bucket,
+			Key:    &s3Key,
+		})
+	}()
+
+	// Set up temporary file for downloaded
+	downloadFile, err := ioutil.TempFile("/tmp", "osbuild-composer-test-aws-download-")
+	handleErrors(t, err)
+	defer os.Remove(downloadFile.Name())
+
+	// Download the object from S3
+	downloader := s3manager.NewDownloader(sess)
+
+	n, err := downloader.Download(downloadFile, &s3.GetObjectInput{
+		Bucket: &bucket,
+		Key:    &s3Key,
+	})
+
+	if err != nil {
+		t.Fatalf("downloader cannot download s3 object: %s", err.Error())
+	}
+
+	if n != int64(fileLength) {
+		t.Fatalf("downloaded file length is wrong, expected: %d, got: %d", fileLength, n)
+	}
+
+	// Seek the downloaded file to the beginning
+	_, err = downloadFile.Seek(0, 0)
+	handleErrors(t, err)
+
+	downloadedFileContent, err := ioutil.ReadAll(downloadFile)
+	handleErrors(t, err)
+
+	if !bytes.Equal(content, downloadedFileContent) {
+		t.Errorf("downloaded file isn't matching the uploaded one")
+	}
+}
+
+func createSession(accessKeyId string, secretAccessKey string, region string) (*session.Session, error) {
+	creds := credentials.NewStaticCredentials(accessKeyId, secretAccessKey, "")
+
+	return session.NewSession(&aws.Config{
+		Credentials: creds,
+		Region:      &region,
+	})
+
+}