feat: bill OpenAI cache_write_tokens at cache-creation price with zero clamp

Parse OpenAI's native cache_write_tokens (chat prompt_tokens_details /
responses input_tokens_details), bill it at the cache-creation ratio, and
clamp the uncached prompt remainder at zero since cached + cache-write can
exceed prompt_tokens. Propagate the field through chat/responses/claude
format conversions and tiered expression billing (cc variable).
This commit is contained in:
CaIon
2026-07-11 21:18:49 +08:00
parent c36418c863
commit 48068ce923
18 changed files with 158 additions and 20 deletions
@@ -216,6 +216,9 @@ func buildOpenAIStyleUsageFromClaudeUsage(usage *dto.Usage) dto.Usage {
usage.ClaudeCacheCreation1hTokens,
)
cacheCreationTokens := cacheCreationTokensForOpenAIUsage(usage)
// Expose the standard OpenAI cache-write field alongside the legacy
// cached_creation_tokens so OpenAI-format clients can bill cache writes.
clone.PromptTokensDetails.CacheWriteTokens = cacheCreationTokens
totalInputTokens := usage.PromptTokens + usage.PromptTokensDetails.CachedTokens + cacheCreationTokens
clone.PromptTokens = totalInputTokens
clone.InputTokens = totalInputTokens
@@ -39,10 +39,21 @@ func buildClaudeUsageFromOpenAIUsage(oaiUsage *dto.Usage) *dto.ClaudeUsage {
oaiUsage.ClaudeCacheCreation5mTokens,
oaiUsage.ClaudeCacheCreation1hTokens,
)
cacheCreationTokens := oaiUsage.PromptTokensDetails.CacheCreationTokensTotal()
inputTokens := oaiUsage.PromptTokens
if oaiUsage.PromptTokensDetails.CacheWriteTokens > 0 {
// OpenAI native cache-write usage counts cached and cache-write tokens
// inside prompt_tokens, while Claude semantics reports input_tokens
// excluding both; the uncached remainder clamps at zero.
inputTokens = oaiUsage.PromptTokens - oaiUsage.PromptTokensDetails.CachedTokens - cacheCreationTokens
if inputTokens < 0 {
inputTokens = 0
}
}
usage := &dto.ClaudeUsage{
InputTokens: oaiUsage.PromptTokens,
InputTokens: inputTokens,
OutputTokens: oaiUsage.CompletionTokens,
CacheCreationInputTokens: oaiUsage.PromptTokensDetails.CachedCreationTokens,
CacheCreationInputTokens: cacheCreationTokens,
CacheReadInputTokens: oaiUsage.PromptTokensDetails.CachedTokens,
BillingUsage: billingUsage,
}
@@ -79,6 +79,30 @@ func TestResponseOpenAI2ClaudeUsageCarriesOpenAIBillingUsage(t *testing.T) {
assert.Nil(t, resp.Usage.BillingUsage.OpenAIUsage.BillingUsage)
}
func TestBuildClaudeUsageFromOpenAICacheWriteUsage(t *testing.T) {
usage := buildClaudeUsageFromOpenAIUsage(&dto.Usage{
PromptTokens: 3619,
CompletionTokens: 36,
TotalTokens: 3655,
PromptTokensDetails: dto.InputTokenDetails{
CachedTokens: 2921,
CacheWriteTokens: 3616,
},
})
require.NotNil(t, usage)
// Claude semantics reports input_tokens excluding cache read/write; the
// remainder 3619-2921-3616 clamps to 0.
assert.Equal(t, 0, usage.InputTokens)
assert.Equal(t, 2921, usage.CacheReadInputTokens)
assert.Equal(t, 3616, usage.CacheCreationInputTokens)
assert.Equal(t, 36, usage.OutputTokens)
require.NotNil(t, usage.BillingUsage)
require.NotNil(t, usage.BillingUsage.OpenAIUsage)
assert.Equal(t, dto.BillingUsageSemanticOpenAI, usage.BillingUsage.Semantic)
assert.Equal(t, 3616, usage.BillingUsage.OpenAIUsage.PromptTokensDetails.CacheWriteTokens)
}
func TestStreamResponseOpenAI2ClaudeClosesTextThinkingAndToolBlocks(t *testing.T) {
info := &relaycommon.RelayInfo{
ClaudeConvertInfo: &relaycommon.ClaudeConvertInfo{
@@ -137,6 +137,7 @@ func UsageFromChatUsage(src *dto.Usage) *dto.Usage {
src.PromptTokensDetails.ImageTokens != 0 ||
src.PromptTokensDetails.AudioTokens != 0 ||
src.PromptTokensDetails.CachedCreationTokens != 0 ||
src.PromptTokensDetails.CacheWriteTokens != 0 ||
src.PromptTokensDetails.TextTokens != 0 {
details := src.PromptTokensDetails
usage.InputTokensDetails = &details
@@ -156,6 +156,7 @@ func UsageFromResponsesUsage(src *dto.Usage) *dto.Usage {
if src.InputTokensDetails != nil {
usage.PromptTokensDetails.CachedTokens = src.InputTokensDetails.CachedTokens
usage.PromptTokensDetails.CachedCreationTokens = src.InputTokensDetails.CachedCreationTokens
usage.PromptTokensDetails.CacheWriteTokens = src.InputTokensDetails.CacheWriteTokens
usage.PromptTokensDetails.TextTokens = src.InputTokensDetails.TextTokens
usage.PromptTokensDetails.ImageTokens = src.InputTokensDetails.ImageTokens
usage.PromptTokensDetails.AudioTokens = src.InputTokensDetails.AudioTokens
@@ -277,6 +277,7 @@ func TestConvertResponseProviderToOAIChatUsage(t *testing.T) {
assert.Equal(t, 22, toChat.Usage.TotalTokens)
assert.Equal(t, 3, toChat.Usage.PromptTokensDetails.CachedTokens)
assert.Equal(t, 4, toChat.Usage.PromptTokensDetails.CachedCreationTokens)
assert.Equal(t, 4, toChat.Usage.PromptTokensDetails.CacheWriteTokens)
require.NotNil(t, toChat.Usage.BillingUsage)
require.NotNil(t, toChat.Usage.BillingUsage.ClaudeUsage)
assert.Equal(t, dto.BillingUsageSourceClaudeMessages, toChat.Usage.BillingUsage.Source)
@@ -539,6 +540,7 @@ func TestResponseUsageMatrixChatAndResponsesDetails(t *testing.T) {
PromptTokensDetails: dto.InputTokenDetails{
CachedTokens: 3,
CachedCreationTokens: 2,
CacheWriteTokens: 6,
TextTokens: 4,
AudioTokens: 1,
ImageTokens: 5,
@@ -558,6 +560,7 @@ func TestResponseUsageMatrixChatAndResponsesDetails(t *testing.T) {
require.NotNil(t, result.Usage.InputTokensDetails)
assert.Equal(t, 3, result.Usage.InputTokensDetails.CachedTokens)
assert.Equal(t, 2, result.Usage.InputTokensDetails.CachedCreationTokens)
assert.Equal(t, 6, result.Usage.InputTokensDetails.CacheWriteTokens)
assert.Equal(t, 4, result.Usage.InputTokensDetails.TextTokens)
assert.Equal(t, 1, result.Usage.InputTokensDetails.AudioTokens)
assert.Equal(t, 5, result.Usage.InputTokensDetails.ImageTokens)
@@ -579,6 +582,7 @@ func TestResponseUsageMatrixChatAndResponsesDetails(t *testing.T) {
InputTokensDetails: &dto.InputTokenDetails{
CachedTokens: 4,
CachedCreationTokens: 1,
CacheWriteTokens: 7,
TextTokens: 5,
AudioTokens: 2,
ImageTokens: 1,
@@ -598,6 +602,7 @@ func TestResponseUsageMatrixChatAndResponsesDetails(t *testing.T) {
assert.Equal(t, 21, result.Usage.TotalTokens)
assert.Equal(t, 4, result.Usage.PromptTokensDetails.CachedTokens)
assert.Equal(t, 1, result.Usage.PromptTokensDetails.CachedCreationTokens)
assert.Equal(t, 7, result.Usage.PromptTokensDetails.CacheWriteTokens)
assert.Equal(t, 5, result.Usage.PromptTokensDetails.TextTokens)
assert.Equal(t, 2, result.Usage.PromptTokensDetails.AudioTokens)
assert.Equal(t, 1, result.Usage.PromptTokensDetails.ImageTokens)
+8 -1
View File
@@ -208,7 +208,7 @@ func calculateTextQuotaSummary(ctx *gin.Context, relayInfo *relaycommon.RelayInf
summary.CompletionTokens = usage.CompletionTokens
summary.TotalTokens = usage.PromptTokens + usage.CompletionTokens
summary.CacheTokens = usage.PromptTokensDetails.CachedTokens
summary.CacheCreationTokens = usage.PromptTokensDetails.CachedCreationTokens
summary.CacheCreationTokens = usage.PromptTokensDetails.CacheCreationTokensTotal()
summary.CacheCreationTokens5m = usage.ClaudeCacheCreation5mTokens
summary.CacheCreationTokens1h = usage.ClaudeCacheCreation1hTokens
summary.ImageTokens = usage.PromptTokensDetails.ImageTokens
@@ -294,6 +294,13 @@ func calculateTextQuotaSummary(ctx *gin.Context, relayInfo *relaycommon.RelayInf
}
}
// OpenAI cache-write usage can report cached_tokens + cache_write_tokens
// exceeding prompt_tokens; the uncached remainder must clamp at zero so
// billing never subtracts more than the reported input.
if baseTokens.IsNegative() {
baseTokens = decimal.Zero
}
promptQuota := baseTokens.Add(cachedTokensWithRatio).Add(imageTokensWithRatio).Add(cachedCreationTokensWithRatio)
completionQuota := dCompletionTokens.Mul(dCompletionRatio)
quotaCalculateDecimal := promptQuota.Add(completionQuota).Mul(ratio)
+56
View File
@@ -375,6 +375,62 @@ func TestCalculateTextQuotaSummaryHandlesLegacyClaudeDerivedOpenAIUsage(t *testi
require.Equal(t, 1624, summary.Quota)
}
func TestCalculateTextQuotaSummaryBillsOpenAICacheWriteTokens(t *testing.T) {
gin.SetMode(gin.TestMode)
w := httptest.NewRecorder()
ctx, _ := gin.CreateTestContext(w)
relayInfo := &relaycommon.RelayInfo{
RelayFormat: types.RelayFormatOpenAI,
OriginModelName: "gpt-5.1",
PriceData: types.PriceData{
ModelRatio: 1,
CompletionRatio: 2,
CacheRatio: 0.1,
CacheCreationRatio: 1.25,
GroupRatioInfo: types.GroupRatioInfo{GroupRatio: 1},
},
StartTime: time.Now(),
}
t.Run("uncached remainder stays positive", func(t *testing.T) {
usage := &dto.Usage{
PromptTokens: 1473,
CompletionTokens: 19,
PromptTokensDetails: dto.InputTokenDetails{
CacheWriteTokens: 1470,
},
}
summary := calculateTextQuotaSummary(ctx, relayInfo, usage)
require.Equal(t, 1470, summary.CacheCreationTokens)
// (1473-0-1470) + 1470*1.25 + 19*2 = 3 + 1837.5 + 38 = 1878.5 => 1879
require.Equal(t, 1879, summary.Quota)
})
t.Run("uncached remainder clamps to zero", func(t *testing.T) {
// Real OpenAI payload shape: cached_tokens + cache_write_tokens exceeds
// prompt_tokens, so the uncached remainder must clamp to 0 instead of
// producing a negative charge component.
usage := &dto.Usage{
PromptTokens: 3619,
CompletionTokens: 36,
PromptTokensDetails: dto.InputTokenDetails{
CachedTokens: 2921,
CacheWriteTokens: 3616,
},
}
summary := calculateTextQuotaSummary(ctx, relayInfo, usage)
require.Equal(t, 3619, summary.PromptTokens)
require.Equal(t, 3616, summary.CacheCreationTokens)
// max(3619-2921-3616, 0) + 2921*0.1 + 3616*1.25 + 36*2 = 4884.1 => 4884
require.Equal(t, 4884, summary.Quota)
})
}
func TestCalculateTextQuotaSummarySeparatesOpenRouterCacheReadFromPromptBilling(t *testing.T) {
gin.SetMode(gin.TestMode)
w := httptest.NewRecorder()
+1 -1
View File
@@ -22,7 +22,7 @@ func BuildTieredTokenParams(usage *dto.Usage, isClaudeUsageSemantic bool, usedVa
p := float64(usage.PromptTokens)
c := float64(usage.CompletionTokens)
cr := float64(usage.PromptTokensDetails.CachedTokens)
cc5m := float64(usage.PromptTokensDetails.CachedCreationTokens)
cc5m := float64(usage.PromptTokensDetails.CacheCreationTokensTotal())
cc1h := float64(0)
if usage.UsageSemantic == "anthropic" {