feat: add backend

internal/client/http.go

@@ -0,0 +1,81 @@
+package client
+
+import (
+	"crypto/md5"
+	"encoding/hex"
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+	"time"
+
+	"github.com/rs/zerolog/log"
+)
+
+type DownloadFileResponse struct {
+	Body     *io.ReadCloser
+	FileName string
+}
+
+type HttpClient struct {
+	http *http.Client
+}
+
+func NewHttpClient() *HttpClient {
+	httpClient := &http.Client{
+		Timeout: time.Second * 10,
+	}
+	return &HttpClient{
+		http: httpClient,
+	}
+}
+
+func (c *HttpClient) DownloadFile(url string, opts map[string]string) (*DownloadFileResponse, error) {
+	if url == "" {
+		return nil, nil
+	}
+
+	// create md5 hash of url for tmp file
+	hash := md5.Sum([]byte(url))
+	hashString := hex.EncodeToString(hash[:])
+	tmpFileName := fmt.Sprintf("/tmp/%v", hashString)
+
+	log.Debug().Msgf("tmpFileName: %v", tmpFileName)
+
+	// Create the file
+	out, err := os.Create(tmpFileName)
+	if err != nil {
+		return nil, err
+	}
+
+	defer out.Close()
+
+	// Get the data
+	resp, err := http.Get(url)
+	if err != nil {
+		// TODO better error message
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	// retry logic
+
+	if resp.StatusCode != 200 {
+		return nil, err
+	}
+
+	// Write the body to file
+	_, err = io.Copy(out, resp.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	// remove file if fail
+
+	res := DownloadFileResponse{
+		Body:     &resp.Body,
+		FileName: tmpFileName,
+	}
+
+	return &res, nil
+}