feat(inspector): add buffer, sseMerger, conversationNormalizer, llmMetadataExtractor (F4)

This commit is contained in:
diegosouzapw
2026-05-27 21:44:37 -03:00
parent ddf6b0ef63
commit 482cfbcdad
4 changed files with 1092 additions and 0 deletions

View File

@@ -0,0 +1,201 @@
/**
* In-memory ring buffer for intercepted traffic.
*
* Stores up to `INSPECTOR_BUFFER_SIZE` (default 1000) entries; rotates
* oldest-first when capacity is reached. Auto-applies kind detection and
* context-key fingerprinting on push, and broadcasts mutations to all
* subscribers (WebSocket consumers).
*
* Body sizes are clamped to `INSPECTOR_MAX_BODY_KB` (default 1024 KiB) and
* marked with a truncation suffix so the UI does not have to guess.
*
* See `_orchestration/master-plan-group-A.md` §3.6 and
* `12-traffic-inspector.plan.md` §4.1.
*/
import { computeContextKey } from "./contextKey.ts";
import { detectKind } from "./kindDetector.ts";
import type { InterceptedRequest, ListFilters, WsEvent } from "./types.ts";
const TRUNCATION_MARKER = "\n…(truncated for performance)";
function parseEnvNumber(value: string | undefined, fallback: number): number {
if (!value) return fallback;
const parsed = Number(value);
if (!Number.isFinite(parsed) || parsed <= 0) return fallback;
return parsed;
}
function getMaxBodyBytes(): number {
const kb = parseEnvNumber(process.env.INSPECTOR_MAX_BODY_KB, 1024);
return Math.max(1, Math.floor(kb)) * 1024;
}
function capBody(body: string | null, maxBytes: number): string | null {
if (body == null) return body;
if (body.length <= maxBytes) return body;
return body.slice(0, maxBytes) + TRUNCATION_MARKER;
}
function statusBucket(status: InterceptedRequest["status"]): string {
if (status === "error") return "error";
if (status === "in-flight") return "in-flight";
if (typeof status !== "number") return "unknown";
if (status >= 200 && status < 300) return "2xx";
if (status >= 300 && status < 400) return "3xx";
if (status >= 400 && status < 500) return "4xx";
if (status >= 500 && status < 600) return "5xx";
return "unknown";
}
function matchesFilters(req: InterceptedRequest, filters?: ListFilters): boolean {
if (!filters) return true;
if (filters.profile && filters.profile !== "all") {
if (filters.profile === "llm" && req.detectedKind !== "llm") return false;
if (filters.profile === "custom" && req.source !== "custom-host") return false;
}
if (filters.host && req.host !== filters.host) return false;
if (filters.agent && req.agent !== filters.agent) return false;
if (filters.source && req.source !== filters.source) return false;
if (filters.sessionId && req.sessionId !== filters.sessionId) return false;
if (filters.status) {
const bucket = statusBucket(req.status);
if (bucket !== filters.status) return false;
}
return true;
}
/**
* Ring buffer with broadcast support.
*
* Designed to be process-singleton (`globalTrafficBuffer`); tests can
* instantiate isolated buffers when needed.
*/
export class TrafficBuffer {
private buffer: InterceptedRequest[] = [];
private subscribers = new Set<(ev: WsEvent) => void>();
private maxSize: number;
private maxBodyBytes: number;
constructor(
maxSize: number = parseEnvNumber(process.env.INSPECTOR_BUFFER_SIZE, 1000),
maxBodyBytes: number = getMaxBodyBytes()
) {
this.maxSize = Math.max(1, Math.floor(maxSize));
this.maxBodyBytes = Math.max(1, Math.floor(maxBodyBytes));
}
/**
* Append a new intercepted request. Applies kind detection and
* context-key fingerprinting if missing, and clamps body sizes.
* Broadcasts a `new` event to all subscribers.
*/
push(req: InterceptedRequest): void {
if (!req.detectedKind) {
req.detectedKind = detectKind(req);
}
if (!req.contextKey && req.detectedKind === "llm") {
const key = computeContextKey(req);
if (key) req.contextKey = key;
}
req.requestBody = capBody(req.requestBody, this.maxBodyBytes);
req.responseBody = capBody(req.responseBody, this.maxBodyBytes);
this.buffer.push(req);
while (this.buffer.length > this.maxSize) {
this.buffer.shift();
}
this.broadcast({ type: "new", data: req });
}
/**
* Update an existing entry in place by id. No-op if the id is unknown
* (e.g. already rotated out). Broadcasts an `update` event on success.
*/
update(id: string, req: InterceptedRequest): void {
const idx = this.buffer.findIndex((r) => r.id === id);
if (idx < 0) return;
req.requestBody = capBody(req.requestBody, this.maxBodyBytes);
req.responseBody = capBody(req.responseBody, this.maxBodyBytes);
this.buffer[idx] = req;
this.broadcast({ type: "update", data: req });
}
/**
* Lookup by id (linear scan — buffer is bounded to ~1000 entries).
*/
get(id: string): InterceptedRequest | null {
return this.buffer.find((r) => r.id === id) ?? null;
}
/**
* Return a filtered snapshot of the buffer. Filtering is in-memory and
* cheap (~O(maxSize)). A new array is returned each call.
*/
list(filters?: ListFilters): InterceptedRequest[] {
if (!filters) return [...this.buffer];
return this.buffer.filter((r) => matchesFilters(r, filters));
}
/**
* Empty the buffer and notify subscribers. Subscriber count is preserved.
*/
clear(): void {
this.buffer = [];
this.broadcast({ type: "clear" });
}
/**
* Register a listener. Immediately receives a `snapshot` event with the
* current buffer state. Returns an `unsubscribe` function.
*/
subscribe(fn: (ev: WsEvent) => void): () => void {
this.subscribers.add(fn);
try {
fn({ type: "snapshot", data: [...this.buffer] });
} catch {
// a subscriber's snapshot handler failure must not break subscription
}
return () => {
this.subscribers.delete(fn);
};
}
/**
* Current subscriber count — exposed for tests / diagnostics.
*/
subscriberCount(): number {
return this.subscribers.size;
}
/**
* Current entry count — exposed for tests / diagnostics.
*/
size(): number {
return this.buffer.length;
}
private broadcast(ev: WsEvent): void {
for (const fn of this.subscribers) {
try {
fn(ev);
} catch {
// one subscriber's failure must not block others
}
}
}
}
/**
* Process-wide singleton consumed by `agentBridgeHook`, `httpProxyServer`,
* REST/WS routes, and tests.
*/
export const globalTrafficBuffer = new TrafficBuffer();

View File

@@ -0,0 +1,393 @@
/**
* Conversation normalizer — converts OpenAI / Anthropic / Gemini request +
* response payloads into a single provider-agnostic shape.
*
* MIT — port from https://github.com/chouzz/llm-interceptor (ui/utils.ts)
*
* Returns `null` for non-LLM requests or payloads we cannot understand —
* never throws — so the renderer can fall back to the raw view.
*/
import { mergeStream, parseSseStream } from "./sseMerger.ts";
import type {
InterceptedRequest,
NormalizedBlock,
NormalizedConversation,
NormalizedTurn,
} from "./types.ts";
type NormalizedRole = NormalizedTurn["role"];
function asRecord(value: unknown): Record<string, unknown> | null {
if (value && typeof value === "object" && !Array.isArray(value)) {
return value as Record<string, unknown>;
}
return null;
}
function tryParseJson(value: string | null | undefined): unknown {
if (!value) return null;
try {
return JSON.parse(value);
} catch {
return null;
}
}
function normalizeRole(raw: unknown): NormalizedRole {
if (raw === "system" || raw === "user" || raw === "assistant" || raw === "tool") {
return raw;
}
if (raw === "model") return "assistant";
if (raw === "function") return "tool";
return "user";
}
/**
* OpenAI / Anthropic message content can be a string, or an array of blocks.
* Returns a list of normalized blocks.
*/
function blocksFromOpenAiContent(content: unknown): NormalizedBlock[] {
if (content == null) return [];
if (typeof content === "string") {
if (content.length === 0) return [];
return [{ type: "text", text: content }];
}
if (!Array.isArray(content)) return [];
const out: NormalizedBlock[] = [];
for (const raw of content) {
if (typeof raw === "string") {
out.push({ type: "text", text: raw });
continue;
}
const block = asRecord(raw);
if (!block) continue;
const type = block.type;
if (type === "text" || type === "output_text") {
const text = typeof block.text === "string" ? block.text : "";
out.push({ type: "text", text });
} else if (type === "input_text") {
const text = typeof block.text === "string" ? block.text : "";
out.push({ type: "text", text });
} else if (type === "tool_use") {
out.push({
type: "tool_use",
id: typeof block.id === "string" ? block.id : "",
name: typeof block.name === "string" ? block.name : "",
input: block.input ?? {},
});
} else if (type === "tool_result") {
out.push({
type: "tool_result",
tool_use_id:
typeof block.tool_use_id === "string" ? block.tool_use_id : "",
content: block.content ?? null,
});
} else if (typeof block.text === "string") {
out.push({ type: "text", text: block.text });
}
}
return out;
}
/**
* OpenAI assistant messages may declare `tool_calls`. Each becomes a
* `tool_use` block alongside any text content.
*/
function appendOpenAiToolCalls(
blocks: NormalizedBlock[],
toolCalls: unknown
): NormalizedBlock[] {
if (!Array.isArray(toolCalls)) return blocks;
for (const raw of toolCalls) {
const tc = asRecord(raw);
if (!tc) continue;
const fn = asRecord(tc.function) ?? {};
let parsedInput: unknown = {};
if (typeof fn.arguments === "string") {
try {
parsedInput = JSON.parse(fn.arguments);
} catch {
parsedInput = fn.arguments;
}
} else if (fn.arguments != null) {
parsedInput = fn.arguments;
}
blocks.push({
type: "tool_use",
id: typeof tc.id === "string" ? tc.id : "",
name: typeof fn.name === "string" ? fn.name : "",
input: parsedInput,
});
}
return blocks;
}
/**
* Build NormalizedTurn[] from OpenAI / Anthropic chat messages.
*/
function turnsFromOpenAiMessages(messages: unknown[]): NormalizedTurn[] {
const out: NormalizedTurn[] = [];
for (const raw of messages) {
const msg = asRecord(raw);
if (!msg) continue;
const role = normalizeRole(msg.role);
if (msg.role === "tool" || msg.role === "function") {
const content = msg.content;
out.push({
role: "tool",
blocks: [
{
type: "tool_result",
tool_use_id:
typeof msg.tool_call_id === "string"
? msg.tool_call_id
: typeof msg.name === "string"
? msg.name
: "",
content,
},
],
});
continue;
}
const blocks = blocksFromOpenAiContent(msg.content);
if ("tool_calls" in msg) {
appendOpenAiToolCalls(blocks, msg.tool_calls);
}
if (blocks.length === 0 && msg.content == null && !("tool_calls" in msg)) {
continue;
}
out.push({ role, blocks });
}
return out;
}
/**
* Gemini contents have a different shape: `[{role, parts: [{text|...}]}]`.
*/
function turnsFromGeminiContents(contents: unknown[]): NormalizedTurn[] {
const out: NormalizedTurn[] = [];
for (const raw of contents) {
const turn = asRecord(raw);
if (!turn) continue;
const role = normalizeRole(turn.role);
const blocks: NormalizedBlock[] = [];
if (Array.isArray(turn.parts)) {
for (const partRaw of turn.parts) {
const part = asRecord(partRaw);
if (!part) continue;
if (typeof part.text === "string") {
blocks.push({ type: "text", text: part.text });
} else if (part.functionCall) {
const fc = asRecord(part.functionCall) ?? {};
blocks.push({
type: "tool_use",
id: typeof fc.name === "string" ? fc.name : "",
name: typeof fc.name === "string" ? fc.name : "",
input: fc.args ?? {},
});
} else if (part.functionResponse) {
const fr = asRecord(part.functionResponse) ?? {};
blocks.push({
type: "tool_result",
tool_use_id: typeof fr.name === "string" ? fr.name : "",
content: fr.response ?? null,
});
}
}
}
if (blocks.length > 0) out.push({ role, blocks });
}
return out;
}
/**
* Anthropic Messages API requests carry a top-level `system` field (string
* or array of `{type:"text"|text}` blocks). Convert to a `system` turn.
*/
function systemTurnFromAnthropic(system: unknown): NormalizedTurn | null {
if (!system) return null;
if (typeof system === "string") {
return system.length === 0
? null
: { role: "system", blocks: [{ type: "text", text: system }] };
}
if (!Array.isArray(system)) return null;
const blocks: NormalizedBlock[] = [];
for (const raw of system) {
const item = asRecord(raw);
if (item && typeof item.text === "string") {
blocks.push({ type: "text", text: item.text });
} else if (typeof raw === "string") {
blocks.push({ type: "text", text: raw });
}
}
if (blocks.length === 0) return null;
return { role: "system", blocks };
}
function buildRequestTurns(body: unknown): NormalizedTurn[] | null {
const obj = asRecord(body);
if (!obj) return null;
if (Array.isArray(obj.messages)) {
const turns: NormalizedTurn[] = [];
const systemTurn = systemTurnFromAnthropic(obj.system);
if (systemTurn) turns.push(systemTurn);
turns.push(...turnsFromOpenAiMessages(obj.messages));
return turns;
}
if (Array.isArray(obj.contents)) {
const turns: NormalizedTurn[] = [];
const sysObj = asRecord(obj.systemInstruction);
if (sysObj && Array.isArray(sysObj.parts)) {
const parts: NormalizedBlock[] = [];
for (const partRaw of sysObj.parts) {
const p = asRecord(partRaw);
if (p && typeof p.text === "string") parts.push({ type: "text", text: p.text });
}
if (parts.length > 0) turns.push({ role: "system", blocks: parts });
}
turns.push(...turnsFromGeminiContents(obj.contents));
return turns;
}
if (typeof obj.prompt === "string") {
return [{ role: "user", blocks: [{ type: "text", text: obj.prompt }] }];
}
if (typeof obj.input === "string") {
return [{ role: "user", blocks: [{ type: "text", text: obj.input }] }];
}
if (Array.isArray(obj.input)) {
return turnsFromOpenAiMessages(obj.input);
}
return null;
}
function isSseResponse(req: InterceptedRequest): boolean {
const accept = req.requestHeaders["accept"] ?? req.requestHeaders["Accept"] ?? "";
const ct = req.responseHeaders["content-type"] ?? req.responseHeaders["Content-Type"] ?? "";
return (
accept.includes("event-stream") ||
ct.includes("event-stream") ||
/^\s*event:|^\s*data:/m.test(req.responseBody ?? "")
);
}
function extractAnthropicResponseTurn(message: unknown): NormalizedTurn | null {
const obj = asRecord(message);
if (!obj) return null;
const content = obj.content;
if (!Array.isArray(content)) return null;
const blocks: NormalizedBlock[] = [];
for (const raw of content) {
const block = asRecord(raw);
if (!block) continue;
if (block.type === "text" && typeof block.text === "string") {
blocks.push({ type: "text", text: block.text });
} else if (block.type === "tool_use") {
blocks.push({
type: "tool_use",
id: typeof block.id === "string" ? block.id : "",
name: typeof block.name === "string" ? block.name : "",
input: block.input ?? {},
});
} else if (block.type === "thinking" && typeof block.thinking === "string") {
blocks.push({ type: "text", text: block.thinking });
}
}
if (blocks.length === 0) return null;
return { role: "assistant", blocks };
}
function extractOpenAiResponseTurn(message: unknown): NormalizedTurn | null {
const obj = asRecord(message);
if (!obj || !Array.isArray(obj.choices)) return null;
const first = asRecord(obj.choices[0]);
if (!first) return null;
const msg = asRecord(first.message) ?? asRecord(first.delta);
if (!msg) return null;
const blocks = blocksFromOpenAiContent(msg.content);
if ("tool_calls" in msg) appendOpenAiToolCalls(blocks, msg.tool_calls);
if (blocks.length === 0) return null;
return { role: "assistant", blocks };
}
function extractGeminiResponseTurn(message: unknown): NormalizedTurn | null {
const obj = asRecord(message);
if (!obj || !Array.isArray(obj.candidates)) return null;
const first = asRecord(obj.candidates[0]);
if (!first) return null;
const content = asRecord(first.content);
if (!content || !Array.isArray(content.parts)) return null;
const blocks: NormalizedBlock[] = [];
for (const partRaw of content.parts) {
const part = asRecord(partRaw);
if (!part) continue;
if (typeof part.text === "string") {
blocks.push({ type: "text", text: part.text });
} else if (part.functionCall) {
const fc = asRecord(part.functionCall) ?? {};
blocks.push({
type: "tool_use",
id: typeof fc.name === "string" ? fc.name : "",
name: typeof fc.name === "string" ? fc.name : "",
input: fc.args ?? {},
});
}
}
if (blocks.length === 0) return null;
return { role: "assistant", blocks };
}
function buildResponseTurns(req: InterceptedRequest): NormalizedTurn[] {
const raw = req.responseBody ?? "";
if (!raw) return [];
let payload: unknown = null;
if (isSseResponse(req)) {
const merged = mergeStream(parseSseStream(raw));
payload = merged.message ?? null;
} else {
payload = tryParseJson(raw);
}
if (!payload) return [];
const anth = extractAnthropicResponseTurn(payload);
if (anth) return [anth];
const oai = extractOpenAiResponseTurn(payload);
if (oai) return [oai];
const gem = extractGeminiResponseTurn(payload);
if (gem) return [gem];
return [];
}
/**
* Normalize an intercepted LLM request + response into a provider-agnostic
* conversation. Returns `null` for non-LLM requests or unparseable payloads.
*/
export function normalizeConversation(
req: InterceptedRequest
): NormalizedConversation | null {
if (req.detectedKind !== "llm") return null;
const requestBody = tryParseJson(req.requestBody);
const requestTurns = buildRequestTurns(requestBody);
if (!requestTurns) return null;
const responseTurns = buildResponseTurns(req);
return {
request: requestTurns,
response: responseTurns,
contextKey: req.contextKey ?? null,
};
}

View File

@@ -0,0 +1,182 @@
/**
* Extract LLM-specific metadata from intercepted requests so the UI can
* render summary chips (provider, model, tokens, cost). Provider/api inference
* is host- and path-based; token counts come from the upstream `usage` block.
*
* Replaces the stub `extractLlmMetadata` left in `kindDetector.ts` by F1.
* Cost estimation is deferred to a future audit pass; we return `null`.
*/
import { detectKind } from "./kindDetector.ts";
import { mergeStream, parseSseStream } from "./sseMerger.ts";
import type { InterceptedRequest, LlmMetadata } from "./types.ts";
interface ProviderMatch {
pattern: RegExp;
provider: string;
}
const PROVIDER_MATCHERS: ProviderMatch[] = [
{ pattern: /(^|\.)openai\.com$/i, provider: "openai" },
{ pattern: /(^|\.)openai\.azure\.com$/i, provider: "azure-openai" },
{ pattern: /(^|\.)anthropic\.com$/i, provider: "anthropic" },
{ pattern: /generativelanguage\.googleapis\.com$/i, provider: "gemini" },
{ pattern: /(^|\.)aiplatform\.googleapis\.com$/i, provider: "vertex" },
{ pattern: /(^|\.)mistral\.ai$/i, provider: "mistral" },
{ pattern: /(^|\.)deepseek\.com$/i, provider: "deepseek" },
{ pattern: /(^|\.)groq\.com$/i, provider: "groq" },
{ pattern: /(^|\.)together\.xyz$/i, provider: "together" },
{ pattern: /(^|\.)fireworks\.ai$/i, provider: "fireworks" },
{ pattern: /(^|\.)cohere\.com$/i, provider: "cohere" },
{ pattern: /(^|\.)perplexity\.ai$/i, provider: "perplexity" },
{ pattern: /(^|\.)huggingface\.co$/i, provider: "huggingface" },
{ pattern: /(^|\.)openrouter\.ai$/i, provider: "openrouter" },
{ pattern: /(^|\.)x\.ai$/i, provider: "xai" },
{ pattern: /(^|\.)moonshot\.ai$/i, provider: "moonshot" },
{ pattern: /bigmodel\.cn$/i, provider: "bigmodel" },
{ pattern: /(^|\.)githubcopilot\.com$/i, provider: "github-copilot" },
{ pattern: /(^|\.)cursor\.sh$/i, provider: "cursor" },
{ pattern: /(^|\.)zed\.dev$/i, provider: "zed" },
];
interface ApiKindMatch {
pattern: RegExp;
apiKind: string;
}
const API_KIND_MATCHERS: ApiKindMatch[] = [
{ pattern: /\/(v1|v1beta)?\/?chat\/completions/i, apiKind: "chat.completions" },
{ pattern: /\/(v1|v1beta)\/messages/i, apiKind: "messages" },
{ pattern: /\/(v1|v1beta)?\/?embeddings/i, apiKind: "embeddings" },
{ pattern: /\/(v1|v1beta)?\/?responses/i, apiKind: "responses" },
{ pattern: /\/streamGenerateContent/i, apiKind: "streamGenerateContent" },
{ pattern: /\/generateContent/i, apiKind: "generateContent" },
{ pattern: /\/(v1|v1beta)\/completions/i, apiKind: "completions" },
];
function asRecord(value: unknown): Record<string, unknown> | null {
if (value && typeof value === "object" && !Array.isArray(value)) {
return value as Record<string, unknown>;
}
return null;
}
function safeParseJson(value: string | null | undefined): unknown {
if (!value) return null;
try {
return JSON.parse(value);
} catch {
return null;
}
}
function inferProvider(host: string): string | null {
for (const m of PROVIDER_MATCHERS) {
if (m.pattern.test(host)) return m.provider;
}
return null;
}
function inferApiKind(path: string): string | null {
for (const m of API_KIND_MATCHERS) {
if (m.pattern.test(path)) return m.apiKind;
}
return null;
}
function countMessages(body: Record<string, unknown> | null): number {
if (!body) return 0;
if (Array.isArray(body.messages)) return body.messages.length;
if (Array.isArray(body.contents)) return body.contents.length;
if (Array.isArray(body.input)) return body.input.length;
return 0;
}
function isSseRequest(req: InterceptedRequest): boolean {
const accept = req.requestHeaders["accept"] ?? req.requestHeaders["Accept"] ?? "";
const ct = req.responseHeaders["content-type"] ?? req.responseHeaders["Content-Type"] ?? "";
return (
accept.includes("event-stream") ||
ct.includes("event-stream") ||
/^\s*event:|^\s*data:/m.test(req.responseBody ?? "")
);
}
function maybeNumber(v: unknown): number | null {
return typeof v === "number" && Number.isFinite(v) ? v : null;
}
function extractUsage(resp: unknown): { tokensIn: number | null; tokensOut: number | null } {
// Direct JSON
const respObj = asRecord(resp);
const usage = asRecord(respObj?.usage);
if (usage) {
const inTok =
maybeNumber(usage.prompt_tokens) ??
maybeNumber(usage.input_tokens) ??
maybeNumber((asRecord(usage.promptTokensDetails) ?? {}).total) ??
null;
const outTok =
maybeNumber(usage.completion_tokens) ??
maybeNumber(usage.output_tokens) ??
maybeNumber((asRecord(usage.completionTokensDetails) ?? {}).total) ??
null;
return { tokensIn: inTok, tokensOut: outTok };
}
// Gemini-style usageMetadata
const um = asRecord(respObj?.usageMetadata);
if (um) {
const inTok = maybeNumber(um.promptTokenCount);
const outTok = maybeNumber(um.candidatesTokenCount);
return { tokensIn: inTok, tokensOut: outTok };
}
return { tokensIn: null, tokensOut: null };
}
/**
* Extract LLM metadata. Returns `null` for non-LLM requests; otherwise
* returns best-effort fields (any unknown field is `null`).
*/
export function extractLlmMetadata(req: InterceptedRequest): LlmMetadata | null {
const kind = req.detectedKind ?? detectKind(req);
if (kind !== "llm") return null;
const body = asRecord(safeParseJson(req.requestBody));
let resp: unknown = safeParseJson(req.responseBody);
// If response was SSE, try to merge it for usage metadata.
if (!resp && req.responseBody && isSseRequest(req)) {
const merged = mergeStream(parseSseStream(req.responseBody));
resp = merged.message ?? null;
}
const respObj = asRecord(resp);
const provider = inferProvider(req.host);
const apiKind = inferApiKind(req.path);
const model =
(body && typeof body.model === "string" ? body.model : null) ??
(respObj && typeof respObj.model === "string" ? respObj.model : null) ??
(respObj && typeof respObj.modelVersion === "string" ? respObj.modelVersion : null) ??
null;
const messages = countMessages(body);
const { tokensIn, tokensOut } = extractUsage(resp);
const streamed = isSseRequest(req);
const mappedTo =
req.mappedModel ??
req.requestHeaders["x-omniroute-mapped"] ??
req.requestHeaders["X-Omniroute-Mapped"] ??
null;
return {
provider,
apiKind,
model,
messages,
tokensIn,
tokensOut,
streamed,
mappedTo,
costEstimateUsd: null, // cost table out of scope for F4
};
}

View File

@@ -0,0 +1,316 @@
/**
* SSE merger — reconstructs complete LLM response from streaming SSE chunks.
*
* MIT — port from https://github.com/chouzz/llm-interceptor (merger.py)
*
* Detects API format by chunk shape (not URL — robust to URL rewrite) and
* rebuilds Anthropic / OpenAI / Gemini responses. Falls back to a raw event
* list when the format is unrecognised so the caller never crashes.
*/
export type ApiFormat = "anthropic" | "openai" | "gemini" | "unknown";
export interface SseEvent {
event?: string;
data?: string;
// Parsed JSON payload when `data` was valid JSON.
json?: unknown;
}
export interface MergedResponse {
format: ApiFormat;
message?: unknown;
raw?: SseEvent[];
}
function asRecord(value: unknown): Record<string, unknown> | null {
if (value && typeof value === "object" && !Array.isArray(value)) {
return value as Record<string, unknown>;
}
return null;
}
/**
* Inspect chunk shapes to determine the upstream API. Matches on the first
* recognisable hint; returns `"unknown"` if none match.
*/
export function detectApiFormat(chunks: SseEvent[]): ApiFormat {
for (const c of chunks) {
const j = asRecord(c.json);
if (!j) continue;
if (j.type === "message_start" || j.type === "content_block_delta") return "anthropic";
if (Array.isArray(j.choices)) {
const first = j.choices[0];
if (first && typeof first === "object" && "delta" in first) return "openai";
}
if (Array.isArray(j.candidates)) return "gemini";
}
return "unknown";
}
/**
* Parse a raw SSE stream (the response body string captured by the proxy)
* into discrete events. Empty blocks and `[DONE]` terminators are skipped
* silently; malformed JSON payloads are kept as raw `data` (no `json`).
*/
export function parseSseStream(raw: string): SseEvent[] {
const events: SseEvent[] = [];
if (!raw) return events;
// SSE blocks separated by blank lines — accept both LF and CRLF.
for (const block of raw.split(/\r?\n\r?\n/)) {
if (!block.trim()) continue;
const ev: SseEvent = {};
for (const line of block.split(/\r?\n/)) {
if (line.startsWith("event:")) {
ev.event = line.slice(6).trim();
} else if (line.startsWith("data:")) {
ev.data = (ev.data ?? "") + line.slice(5).trim();
}
}
if (ev.data === undefined) continue;
if (ev.data === "[DONE]") {
events.push(ev);
continue;
}
try {
ev.json = JSON.parse(ev.data);
} catch {
// keep raw data only
}
events.push(ev);
}
return events;
}
interface AnthropicBlock {
type: string;
text?: string;
thinking?: string;
id?: string;
name?: string;
input?: unknown;
}
/**
* Rebuild an Anthropic Messages API response from streaming events.
* Handles `text_delta`, `thinking_delta`, and `input_json_delta` deltas;
* applies `JSON.parse` (best-effort) on accumulated tool-use input.
*/
export function rebuildAnthropic(chunks: SseEvent[]): MergedResponse {
const blocks: AnthropicBlock[] = [];
let message: Record<string, unknown> | null = null;
const inputJsonByIndex: Record<number, string> = {};
for (const c of chunks) {
const j = asRecord(c.json);
if (!j) continue;
const t = j.type;
if (t === "message_start") {
const m = asRecord(j.message);
message = m ? { ...m } : {};
} else if (t === "content_block_start") {
const idx = typeof j.index === "number" ? j.index : blocks.length;
const cb = asRecord(j.content_block);
const block: AnthropicBlock = { type: "text" };
if (cb) {
for (const [k, v] of Object.entries(cb)) (block as Record<string, unknown>)[k] = v;
}
if (block.type === "text" && block.text === undefined) block.text = "";
if (block.type === "thinking" && block.thinking === undefined) block.thinking = "";
if (block.type === "tool_use" && block.input === undefined) block.input = {};
blocks[idx] = block;
} else if (t === "content_block_delta") {
const idx = typeof j.index === "number" ? j.index : 0;
const d = asRecord(j.delta);
if (!d) continue;
// Ensure a block slot exists (some streams skip content_block_start).
const slot = blocks[idx] ?? (blocks[idx] = { type: "text", text: "" });
const dType = d.type;
if (dType === "text_delta" && typeof d.text === "string") {
slot.text = (slot.text ?? "") + d.text;
} else if (dType === "thinking_delta" && typeof d.thinking === "string") {
slot.thinking = (slot.thinking ?? "") + d.thinking;
} else if (dType === "input_json_delta" && typeof d.partial_json === "string") {
inputJsonByIndex[idx] = (inputJsonByIndex[idx] ?? "") + d.partial_json;
}
} else if (t === "content_block_stop") {
const idx = typeof j.index === "number" ? j.index : 0;
const slot = blocks[idx];
if (slot && slot.type === "tool_use" && inputJsonByIndex[idx]) {
try {
slot.input = JSON.parse(inputJsonByIndex[idx]);
} catch {
// keep accumulated string for forensic visibility
slot.input = inputJsonByIndex[idx];
}
}
} else if (t === "message_delta") {
if (!message) message = {};
const d = asRecord(j.delta);
if (d && typeof d.stop_reason === "string") {
message.stop_reason = d.stop_reason;
}
const usage = asRecord(j.usage);
if (usage) {
const prev = asRecord(message.usage) ?? {};
message.usage = { ...prev, ...usage };
}
}
}
const filledBlocks = blocks.filter((b) => b !== undefined);
return {
format: "anthropic",
message: { ...(message ?? {}), content: filledBlocks },
};
}
interface OpenAiToolCall {
index: number;
id?: string;
type?: string;
function: { name: string; arguments: string };
}
interface OpenAiChoice {
index: number;
message: {
role: string;
content: string;
tool_calls?: OpenAiToolCall[];
refusal?: string;
};
finish_reason: string | null;
}
/**
* Rebuild an OpenAI Chat Completions response from streaming events.
* Accumulates content text and tool-call fragments per choice/index.
*/
export function rebuildOpenAI(chunks: SseEvent[]): MergedResponse {
const choicesByIdx: Record<number, OpenAiChoice> = {};
let model: string | null = null;
let usage: unknown = null;
let id: string | null = null;
for (const c of chunks) {
const j = asRecord(c.json);
if (!j) continue;
if (typeof j.model === "string") model = j.model;
if (typeof j.id === "string") id = j.id;
if (j.usage != null) usage = j.usage;
if (!Array.isArray(j.choices)) continue;
for (const raw of j.choices) {
const ch = asRecord(raw);
if (!ch) continue;
const idx = typeof ch.index === "number" ? ch.index : 0;
const slot = (choicesByIdx[idx] ??= {
index: idx,
message: { role: "assistant", content: "" },
finish_reason: null,
});
const delta = asRecord(ch.delta) ?? {};
if (typeof delta.role === "string") slot.message.role = delta.role;
if (typeof delta.content === "string") slot.message.content += delta.content;
if (typeof delta.refusal === "string") {
slot.message.refusal = (slot.message.refusal ?? "") + delta.refusal;
}
if (Array.isArray(delta.tool_calls)) {
slot.message.tool_calls ??= [];
for (const tcRaw of delta.tool_calls) {
const tc = asRecord(tcRaw);
if (!tc) continue;
const ti = typeof tc.index === "number" ? tc.index : 0;
const tcSlot =
slot.message.tool_calls[ti] ??
(slot.message.tool_calls[ti] = {
index: ti,
function: { name: "", arguments: "" },
});
if (typeof tc.id === "string") tcSlot.id = tc.id;
if (typeof tc.type === "string") tcSlot.type = tc.type;
const fn = asRecord(tc.function);
if (fn) {
if (typeof fn.name === "string") tcSlot.function.name += fn.name;
if (typeof fn.arguments === "string") tcSlot.function.arguments += fn.arguments;
}
}
}
if (typeof ch.finish_reason === "string") slot.finish_reason = ch.finish_reason;
}
}
return {
format: "openai",
message: {
id,
model,
choices: Object.values(choicesByIdx).sort((a, b) => a.index - b.index),
usage,
},
};
}
/**
* Rebuild a Gemini `generateContent`-style response from streaming events.
* Concatenates all parts across emitted candidates into a single candidate.
*/
export function rebuildGemini(chunks: SseEvent[]): MergedResponse {
const parts: unknown[] = [];
let usageMetadata: unknown = null;
let finishReason: unknown = null;
let modelVersion: string | null = null;
for (const c of chunks) {
const j = asRecord(c.json);
if (!j) continue;
if (j.usageMetadata != null) usageMetadata = j.usageMetadata;
if (typeof j.modelVersion === "string") modelVersion = j.modelVersion;
if (!Array.isArray(j.candidates)) continue;
for (const candRaw of j.candidates) {
const cand = asRecord(candRaw);
if (!cand) continue;
if (cand.finishReason != null) finishReason = cand.finishReason;
const content = asRecord(cand.content);
if (!content) continue;
const ps = content.parts;
if (Array.isArray(ps)) {
for (const p of ps) parts.push(p);
}
}
}
return {
format: "gemini",
message: {
candidates: [
{
content: { parts, role: "model" },
...(finishReason != null ? { finishReason } : {}),
},
],
...(modelVersion ? { modelVersion } : {}),
...(usageMetadata != null ? { usageMetadata } : {}),
},
};
}
/**
* Merge an array of SSE events into a single rebuilt response. Returns
* `{ format: "unknown", raw }` (no throw) for unrecognised shapes.
*/
export function mergeStream(chunks: SseEvent[]): MergedResponse {
const format = detectApiFormat(chunks);
switch (format) {
case "anthropic":
return rebuildAnthropic(chunks);
case "openai":
return rebuildOpenAI(chunks);
case "gemini":
return rebuildGemini(chunks);
default:
return { format: "unknown", raw: chunks };
}
}