detect download failures when StatusCode > 200

internal/download/fetch.go

@@ -41,6 +41,9 @@ func (HTTPFetcher) Get(uri string) (io.ReadCloser, error) {
 	if err != nil {
 		return nil, errors.Wrapf(err, "failed to download %q", uri)
 	}
+	if resp.StatusCode > 200 {
+		return nil, errors.Errorf("failed to download %q, status code %d", uri, resp.StatusCode)
+	}
 	return resp.Body, nil
 }
 

internal/download/fetch_test.go

@@ -0,0 +1,129 @@
+// Copyright 2019 The Kubernetes Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package download
+
+import (
+	"bytes"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"reflect"
+	"strconv"
+	"strings"
+	"testing"
+)
+
+func TestHTTPFetcher_Get(t *testing.T) {
+	type args struct {
+		uri string
+	}
+	tests := []struct {
+		name    string
+		h       HTTPFetcher
+		args    args
+		want    io.ReadCloser
+		wantErr bool
+	}{
+		{
+			name: "200",
+			h:    HTTPFetcher{},
+			args: args{
+				uri: "content:foo",
+			},
+			want:    io.NopCloser(bytes.NewBufferString("foo")),
+			wantErr: false,
+		},
+		{
+			name: "404",
+			h:    HTTPFetcher{},
+			args: args{
+				uri: "404",
+			},
+			want:    nil,
+			wantErr: true,
+		},
+		{
+			name: "401",
+			h:    HTTPFetcher{},
+			args: args{
+				uri: "401",
+			},
+			want:    nil,
+			wantErr: true,
+		},
+	}
+
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != "GET" {
+			t.Fatalf("test server download %v must always use GET, used %s instead", r.URL, r.Method)
+		}
+		// return everything after colon as content to the client, return 200
+		if strings.HasPrefix(r.URL.Path, "/content:") {
+			if len(r.URL.Path) < 10 {
+				w.WriteHeader(http.StatusBadRequest)
+				t.Fatalf("test server received content directive with no content")
+				return
+			}
+			content := r.URL.Path[9:]
+			_, err := w.Write([]byte(content))
+			if err != nil {
+				t.Fatalf("test server could not write content response: %s", err)
+			}
+			return
+		}
+		// assume that any other resource is just asking to return a specific return code
+		i, err := strconv.Atoi(r.URL.Path[1:])
+		if err != nil {
+			t.Fatalf("test server url received unknown directive: %v", r.URL.Path)
+		}
+		w.WriteHeader(i)
+	}))
+	defer ts.Close()
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			h := HTTPFetcher{}
+			got, err := h.Get(ts.URL + "/" + tt.args.uri)
+			if got != nil {
+				defer got.Close()
+			}
+			if (err != nil) != tt.wantErr {
+				t.Errorf("HTTPFetcher.Get() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if (tt.want != nil) && (got == nil) {
+				t.Error("HTTPFetcher.Get() = nil, want not nil")
+				return
+			}
+			if (tt.want == nil) && (got != nil) {
+				t.Error("HTTPFetcher.Get() != nil, want nil")
+				return
+			}
+			if got == nil && tt.want == nil {
+				return
+			}
+			gotS, err := io.ReadAll(got)
+			if err != nil {
+				t.Errorf("HTTPFetcher.Get() could not read body: %s", err)
+				return
+			}
+			// this is a local buffer, no error will be returned
+			wantS, _ := io.ReadAll(tt.want)
+			if !reflect.DeepEqual(gotS, wantS) {
+				t.Errorf("HTTPFetcher.Get() = %v, want %v", gotS, wantS)
+			}
+		})
+	}
+}