Add token usage stats and consolidate credentials in SQLite

- New internal/stats (types) and internal/store (SQLite owner: requests + credentials tables, WAL); store implements stats.Recorder. - Stream (SSE tee) and non-stream chat paths parse upstream usage incl. cached_tokens and record per-request; add /api/stats, /api/stats/reset, /admin/stats HTML with cache hit rate. - Drop credentials.json: remove auth file I/O and ZHANLU_CREDENTIALS_FILE; credential precedence is env vars > db row.
2026-08-19 15:52:00 +08:00
parent dd5c560b64
commit fa9640d919
15 changed files with 1101 additions and 103 deletions
@@ -0,0 +1,83 @@
+// Package stats defines the types and helpers for OpenAI-compatible token
+// usage statistics recorded by the zhanlu proxy. The concrete SQLite-backed
+// recorder lives in internal/store; this package is dependency-free so it can
+// be referenced by both store and server without import cycles.
+package stats
+
+import "time"
+
+// Record is a single chat-completion usage observation.
+type Record struct {
+	Ts               time.Time `json:"ts"`
+	Model            string    `json:"model"`
+	Stream           bool      `json:"stream"`
+	PromptTokens     int       `json:"prompt_tokens"`
+	CompletionTokens int       `json:"completion_tokens"`
+	TotalTokens      int       `json:"total_tokens"`
+	ReasoningTokens  int       `json:"reasoning_tokens"`
+	CachedTokens     int       `json:"cached_tokens"`
+	Status           string    `json:"status"` // "success" | "upstream_error"
+	LatencyMs        int64     `json:"latency_ms"`
+}
+
+// Query filters the recorded stats. Zero-value time fields mean unbounded on
+// that end; empty Model means all models. Limit caps the recent-records list
+// (0 = default). Stream filters by streaming mode (nil = both).
+type Query struct {
+	Since  time.Time
+	Until  time.Time
+	Model  string
+	Limit  int
+	Stream *bool
+}
+
+// Totals aggregates request counts and token sums over a filtered set.
+type Totals struct {
+	Requests         int     `json:"requests"`
+	SuccessRequests  int     `json:"success_requests"`
+	ErrorRequests    int     `json:"error_requests"`
+	PromptTokens     int64   `json:"prompt_tokens"`
+	CompletionTokens int64   `json:"completion_tokens"`
+	TotalTokens      int64   `json:"total_tokens"`
+	ReasoningTokens  int64   `json:"reasoning_tokens"`
+	CachedTokens     int64   `json:"cached_tokens"`
+	CacheRate        float64 `json:"cache_rate"` // cached_tokens / prompt_tokens, 0..1
+}
+
+// ModelStat is a per-model aggregation row.
+type ModelStat struct {
+	Model            string `json:"model"`
+	Requests         int    `json:"requests"`
+	PromptTokens     int64  `json:"prompt_tokens"`
+	CompletionTokens int64  `json:"completion_tokens"`
+	TotalTokens      int64  `json:"total_tokens"`
+	CachedTokens     int64  `json:"cached_tokens"`
+}
+
+// DayStat is a per-day aggregation row (server-local time, YYYY-MM-DD).
+type DayStat struct {
+	Day              string `json:"day"`
+	Requests         int    `json:"requests"`
+	PromptTokens     int64  `json:"prompt_tokens"`
+	CompletionTokens int64  `json:"completion_tokens"`
+	TotalTokens      int64  `json:"total_tokens"`
+	CachedTokens     int64  `json:"cached_tokens"`
+}
+
+// Summary is the full result returned by a Recorder's Stats query.
+type Summary struct {
+	Totals   Totals      `json:"totals"`
+	PerModel []ModelStat `json:"per_model"`
+	Daily    []DayStat   `json:"daily"`
+	Recent   []Record    `json:"recent"`
+}
+
+// Recorder persists and queries usage statistics. The concrete implementation
+// lives in internal/store; the interface is declared here so server code can
+// depend on the contract and tests can inject fakes.
+type Recorder interface {
+	Record(r Record) error
+	Stats(q Query) (*Summary, error)
+	Reset() error
+	Close() error
+}