Files
claude-mnemonic/internal/models/download_test.go
T
lukaszraczylo a23b8c4936 fix(models): handle cleanup errors and add download tests
Explicitly discard best-effort cleanup errors (os.Remove/Close) to satisfy errcheck; add hermetic table-driven tests for checksum mismatch, version-bump cache invalidation, and retry exhaustion.
2026-06-19 14:26:35 +01:00

236 lines
8.6 KiB
Go

// Package models provides runtime model download and caching.
package models
import (
"crypto/sha256"
"encoding/hex"
"net/http"
"net/http/httptest"
"os"
"path/filepath"
"strings"
"sync/atomic"
"testing"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
)
// sha256Hex returns the hex-encoded SHA-256 of b.
func sha256Hex(t *testing.T, b []byte) string {
t.Helper()
h := sha256.Sum256(b)
return hex.EncodeToString(h[:])
}
// isolateCacheDir points ModelsDir() at a fresh temp directory by overriding
// the OS cache-dir resolution env vars (HOME and XDG_CACHE_HOME, which
// os.UserCacheDir honors on Linux and macOS). It also clears
// CLAUDE_MNEMONIC_MODEL_DIR so EnsureModel takes the download/cache path
// rather than the local-dir shortcut. It returns the resulting models dir.
func isolateCacheDir(t *testing.T) string {
t.Helper()
home := t.TempDir()
t.Setenv("HOME", home)
t.Setenv("XDG_CACHE_HOME", filepath.Join(home, ".cache"))
t.Setenv("CLAUDE_MNEMONIC_MODEL_DIR", "")
dir := ModelsDir()
require.True(t, strings.HasPrefix(dir, home),
"ModelsDir() %q must live under temp HOME %q for hermetic test", dir, home)
return dir
}
// fileServer returns an httptest server that serves body for any request and
// records how many requests it received.
func fileServer(t *testing.T, body []byte) (*httptest.Server, *int32) {
t.Helper()
var hits int32
srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
atomic.AddInt32(&hits, 1)
_, _ = w.Write(body)
}))
t.Cleanup(srv.Close)
return srv, &hits
}
// TestEnsureModel_Download_CachesValidModel verifies the happy path: a model is
// downloaded, passes checksum verification, and the version file is written.
func TestEnsureModel_Download_CachesValidModel(t *testing.T) {
dir := isolateCacheDir(t)
body := []byte("model-bytes-happy-path")
srv, hits := fileServer(t, body)
const asset = "test-model.onnx"
path, err := EnsureModel(asset, srv.URL, sha256Hex(t, body))
require.NoError(t, err)
assert.Equal(t, filepath.Join(dir, asset), path)
got, err := os.ReadFile(path)
require.NoError(t, err)
assert.Equal(t, body, got, "cached file content must match downloaded body")
ver, err := os.ReadFile(filepath.Join(dir, ".model_version"))
require.NoError(t, err)
assert.Equal(t, ModelVersion, string(ver), "version file must record current ModelVersion")
assert.Equal(t, int32(1), atomic.LoadInt32(hits), "exactly one download on first fetch")
}
// TestEnsureModel_ChecksumMismatch_FailsAndRemoves verifies that a downloaded
// file whose content does not match the expected SHA-256 is rejected with a
// verification error and is not left behind in the cache.
func TestEnsureModel_ChecksumMismatch_FailsAndRemoves(t *testing.T) {
dir := isolateCacheDir(t)
body := []byte("the-actual-downloaded-bytes")
srv, _ := fileServer(t, body)
const asset = "mismatch-model.onnx"
wrongSum := sha256Hex(t, []byte("a-different-expected-payload"))
path, err := EnsureModel(asset, srv.URL, wrongSum)
require.Error(t, err)
assert.Empty(t, path)
assert.Contains(t, err.Error(), "checksum verification")
_, statErr := os.Stat(filepath.Join(dir, asset))
assert.True(t, os.IsNotExist(statErr),
"corrupt download must be removed from cache, got statErr=%v", statErr)
}
// TestEnsureModel_VersionBump_InvalidatesCache verifies that when the on-disk
// .model_version differs from ModelVersion, the cache directory is cleared and
// the model is re-downloaded fresh.
func TestEnsureModel_VersionBump_InvalidatesCache(t *testing.T) {
dir := isolateCacheDir(t)
require.NoError(t, os.MkdirAll(dir, 0700))
// Seed a stale cache: an old version file, a leftover model file, and an
// unrelated sidecar file. Only the version-bump branch wipes the whole dir
// (os.RemoveAll), so the sidecar's removal uniquely proves invalidation ran
// — a plain checksum-driven re-download would leave the sidecar in place.
const asset = "versioned-model.onnx"
staleModel := filepath.Join(dir, asset)
staleSidecar := filepath.Join(dir, "leftover-sidecar.bin")
require.NoError(t, os.WriteFile(staleModel, []byte("stale-garbage"), 0600))
require.NoError(t, os.WriteFile(staleSidecar, []byte("unrelated-leftover"), 0600))
require.NoError(t, os.WriteFile(filepath.Join(dir, ".model_version"), []byte("OLD-VERSION"), 0600))
body := []byte("freshly-downloaded-model-bytes")
srv, hits := fileServer(t, body)
path, err := EnsureModel(asset, srv.URL, sha256Hex(t, body))
require.NoError(t, err)
got, err := os.ReadFile(path)
require.NoError(t, err)
assert.Equal(t, body, got, "stale cached file must be replaced by fresh download")
ver, err := os.ReadFile(filepath.Join(dir, ".model_version"))
require.NoError(t, err)
assert.Equal(t, ModelVersion, string(ver), "version file must be rewritten to current ModelVersion")
assert.Equal(t, int32(1), atomic.LoadInt32(hits),
"version bump must force exactly one re-download, not serve the stale file")
_, sidecarErr := os.Stat(staleSidecar)
assert.True(t, os.IsNotExist(sidecarErr),
"version bump must wipe the whole cache dir, removing unrelated sidecar files")
}
// TestEnsureModel_SameVersionValidCache_NoDownload verifies that a matching
// version file plus a checksum-valid cached file short-circuits the download.
func TestEnsureModel_SameVersionValidCache_NoDownload(t *testing.T) {
dir := isolateCacheDir(t)
require.NoError(t, os.MkdirAll(dir, 0700))
const asset = "cached-model.onnx"
body := []byte("already-cached-valid-bytes")
require.NoError(t, os.WriteFile(filepath.Join(dir, asset), body, 0600))
require.NoError(t, os.WriteFile(filepath.Join(dir, ".model_version"), []byte(ModelVersion), 0600))
// Server would record a hit if EnsureModel wrongly re-downloaded.
srv, hits := fileServer(t, []byte("should-not-be-fetched"))
path, err := EnsureModel(asset, srv.URL, sha256Hex(t, body))
require.NoError(t, err)
assert.Equal(t, filepath.Join(dir, asset), path)
assert.Equal(t, int32(0), atomic.LoadInt32(hits), "valid same-version cache must not trigger a download")
}
// TestEnsureModel_RetryExhaustion_ReturnsError verifies that when every download
// attempt fails (server always returns HTTP 500), EnsureModel exhausts its
// retries and returns an error reporting the attempt count, leaving no model
// file behind.
//
// Note: downloadWithRetries sleeps with exponential backoff between attempts,
// so this test takes ~6s by design; the backoff is production behavior and is
// intentionally not stubbed.
func TestEnsureModel_RetryExhaustion_ReturnsError(t *testing.T) {
if testing.Short() {
t.Skip("skipping retry-exhaustion test (real backoff sleeps) in -short mode")
}
dir := isolateCacheDir(t)
var hits int32
srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
atomic.AddInt32(&hits, 1)
w.WriteHeader(http.StatusInternalServerError)
}))
t.Cleanup(srv.Close)
const asset = "unreachable-model.onnx"
path, err := EnsureModel(asset, srv.URL, sha256Hex(t, []byte("never-served")))
require.Error(t, err)
assert.Empty(t, path)
assert.Contains(t, err.Error(), "attempts", "error must report retry exhaustion")
assert.Equal(t, int32(maxRetries), atomic.LoadInt32(&hits),
"server must be hit exactly maxRetries times")
_, statErr := os.Stat(filepath.Join(dir, asset))
assert.True(t, os.IsNotExist(statErr), "failed download must not leave a model file")
}
// TestEnsureModel_LocalDir verifies the CLAUDE_MNEMONIC_MODEL_DIR shortcut:
// a present, checksum-valid file is returned directly, and a checksum mismatch
// or missing file is reported without any network access.
func TestEnsureModel_LocalDir(t *testing.T) {
body := []byte("local-dir-model-bytes")
validSum := sha256Hex(t, body)
tests := []struct {
name string
writeFile bool
expectSum string
wantErr string
}{
{name: "valid_local_model", writeFile: true, expectSum: validSum, wantErr: ""},
{name: "checksum_mismatch", writeFile: true, expectSum: sha256Hex(t, []byte("other")), wantErr: "checksum mismatch"},
{name: "missing_file", writeFile: false, expectSum: validSum, wantErr: "not found"},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
localDir := t.TempDir()
t.Setenv("CLAUDE_MNEMONIC_MODEL_DIR", localDir)
const asset = "local-model.onnx"
if tt.writeFile {
require.NoError(t, os.WriteFile(filepath.Join(localDir, asset), body, 0600))
}
path, err := EnsureModel(asset, "http://127.0.0.1:0/should-not-be-used", tt.expectSum)
if tt.wantErr != "" {
require.Error(t, err)
assert.Contains(t, err.Error(), tt.wantErr)
assert.Empty(t, path)
return
}
require.NoError(t, err)
assert.Equal(t, filepath.Join(localDir, asset), path)
})
}
}