Files
pubcli/internal/api/client_test.go
teernisse 4310375dc9 Replace io.ReadAll + json.Unmarshal with streaming JSON decoder
Refactor the internal HTTP helper from get() returning raw bytes to
getAndDecode() that streams directly into the target struct via
json.NewDecoder. This eliminates the intermediate []byte allocation
from io.ReadAll on every API response.

The new decoder also validates that responses contain exactly one JSON
value by attempting a second Decode after the primary one — any content
beyond the first value (e.g., concatenated objects from a misbehaving
proxy) returns an error instead of silently discarding it.

Changes:
- api/client.go: Replace get() with getAndDecode(), update FetchStores
  and FetchSavings callers to use the new signature
- api/client_test.go: Add TestFetchSavings_TrailingJSONIsRejected and
  TestFetchStores_MalformedJSONReturnsDecodeError covering the new
  decoder error paths

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
2026-02-23 00:11:24 -05:00

172 lines
4.7 KiB
Go

package api_test
import (
"context"
"encoding/json"
"net/http"
"net/http/httptest"
"testing"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
"github.com/tayloree/publix-deals/internal/api"
)
func ptr(s string) *string { return &s }
func newTestSavingsServer(t *testing.T, storeNumber string, items []api.SavingItem) *httptest.Server {
t.Helper()
return httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
// Verify the PublixStore header is sent
got := r.Header.Get("PublixStore")
if storeNumber != "" {
assert.Equal(t, storeNumber, got, "PublixStore header mismatch")
}
resp := api.SavingsResponse{
Savings: items,
LanguageID: 1,
}
w.Header().Set("Content-Type", "application/json")
json.NewEncoder(w).Encode(resp)
}))
}
func newTestStoreServer(t *testing.T, stores []api.Store) *httptest.Server {
t.Helper()
return httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
assert.NotEmpty(t, r.URL.Query().Get("zipCode"), "zipCode param required")
resp := api.StoreResponse{Stores: stores}
w.Header().Set("Content-Type", "application/json")
json.NewEncoder(w).Encode(resp)
}))
}
func TestFetchSavings(t *testing.T) {
items := []api.SavingItem{
{
ID: "test-1",
Title: ptr("Chicken Breasts"),
Savings: ptr("$3.99 lb"),
Department: ptr("Meat"),
Categories: []string{"meat"},
StartFormatted: "2/18",
EndFormatted: "2/24",
},
{
ID: "test-2",
Title: ptr("Nutella"),
Savings: ptr("Buy 1 Get 1 FREE"),
Categories: []string{"bogo", "grocery"},
},
}
srv := newTestSavingsServer(t, "1425", items)
defer srv.Close()
client := api.NewClientWithBaseURLs(srv.URL, "")
resp, err := client.FetchSavings(context.Background(), "1425")
require.NoError(t, err)
assert.Len(t, resp.Savings, 2)
assert.Equal(t, "Chicken Breasts", *resp.Savings[0].Title)
assert.Equal(t, "Buy 1 Get 1 FREE", *resp.Savings[1].Savings)
}
func TestFetchSavings_EmptyStore(t *testing.T) {
srv := newTestSavingsServer(t, "", nil)
defer srv.Close()
client := api.NewClientWithBaseURLs(srv.URL, "")
resp, err := client.FetchSavings(context.Background(), "")
require.NoError(t, err)
assert.Empty(t, resp.Savings)
}
func TestFetchSavings_ServerError(t *testing.T) {
srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
w.WriteHeader(http.StatusInternalServerError)
}))
defer srv.Close()
client := api.NewClientWithBaseURLs(srv.URL, "")
_, err := client.FetchSavings(context.Background(), "1425")
assert.Error(t, err)
assert.Contains(t, err.Error(), "500")
}
func TestFetchStores(t *testing.T) {
stores := []api.Store{
{Key: "01425", Name: "Peachers Mill", City: "Clarksville", State: "TN", Zip: "37042", Distance: "5"},
{Key: "00100", Name: "Downtown", City: "Nashville", State: "TN", Zip: "37201", Distance: "15"},
}
srv := newTestStoreServer(t, stores)
defer srv.Close()
client := api.NewClientWithBaseURLs("", srv.URL)
result, err := client.FetchStores(context.Background(), "37042", 5)
require.NoError(t, err)
assert.Len(t, result, 2)
assert.Equal(t, "Peachers Mill", result[0].Name)
assert.Equal(t, "01425", result[0].Key)
}
func TestFetchStores_NoResults(t *testing.T) {
srv := newTestStoreServer(t, nil)
defer srv.Close()
client := api.NewClientWithBaseURLs("", srv.URL)
result, err := client.FetchStores(context.Background(), "00000", 5)
require.NoError(t, err)
assert.Empty(t, result)
}
func TestFetchSavings_TrailingJSONIsRejected(t *testing.T) {
srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
w.Header().Set("Content-Type", "application/json")
_, _ = w.Write([]byte(`{"Savings":[],"LanguageId":1} {"extra":true}`))
}))
defer srv.Close()
client := api.NewClientWithBaseURLs(srv.URL, "")
_, err := client.FetchSavings(context.Background(), "1425")
assert.Error(t, err)
assert.Contains(t, err.Error(), "decoding")
}
func TestFetchStores_MalformedJSONReturnsDecodeError(t *testing.T) {
srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
w.Header().Set("Content-Type", "application/json")
_, _ = w.Write([]byte(`{"Stores":`))
}))
defer srv.Close()
client := api.NewClientWithBaseURLs("", srv.URL)
_, err := client.FetchStores(context.Background(), "37042", 5)
assert.Error(t, err)
assert.Contains(t, err.Error(), "decoding")
}
func TestStoreNumber(t *testing.T) {
tests := []struct {
input string
want string
}{
{"01425", "1425"},
{"00100", "100"},
{"1425", "1425"},
{"0", ""},
}
for _, tt := range tests {
assert.Equal(t, tt.want, api.StoreNumber(tt.input), "StoreNumber(%q)", tt.input)
}
}