Files
clawdbot/src/browser/cdp.ts
2025-12-23 00:28:55 +00:00

533 lines
15 KiB
TypeScript

import WebSocket from "ws";
import { rawDataToString } from "../infra/ws.js";
type CdpResponse = {
id: number;
result?: unknown;
error?: { message?: string };
};
type Pending = {
resolve: (value: unknown) => void;
reject: (err: Error) => void;
};
type CdpSendFn = (
method: string,
params?: Record<string, unknown>,
) => Promise<unknown>;
function createCdpSender(ws: WebSocket) {
let nextId = 1;
const pending = new Map<number, Pending>();
const send: CdpSendFn = (
method: string,
params?: Record<string, unknown>,
) => {
const id = nextId++;
const msg = { id, method, params };
ws.send(JSON.stringify(msg));
return new Promise<unknown>((resolve, reject) => {
pending.set(id, { resolve, reject });
});
};
const closeWithError = (err: Error) => {
for (const [, p] of pending) p.reject(err);
pending.clear();
try {
ws.close();
} catch {
// ignore
}
};
ws.on("message", (data) => {
try {
const parsed = JSON.parse(rawDataToString(data)) as CdpResponse;
if (typeof parsed.id !== "number") return;
const p = pending.get(parsed.id);
if (!p) return;
pending.delete(parsed.id);
if (parsed.error?.message) {
p.reject(new Error(parsed.error.message));
return;
}
p.resolve(parsed.result);
} catch {
// ignore
}
});
ws.on("close", () => {
closeWithError(new Error("CDP socket closed"));
});
return { send, closeWithError };
}
async function fetchJson<T>(url: string, timeoutMs = 1500): Promise<T> {
const ctrl = new AbortController();
const t = setTimeout(() => ctrl.abort(), timeoutMs);
try {
const res = await fetch(url, { signal: ctrl.signal });
if (!res.ok) throw new Error(`HTTP ${res.status}`);
return (await res.json()) as T;
} finally {
clearTimeout(t);
}
}
async function withCdpSocket<T>(
wsUrl: string,
fn: (send: CdpSendFn) => Promise<T>,
): Promise<T> {
const ws = new WebSocket(wsUrl, { handshakeTimeout: 5000 });
const { send, closeWithError } = createCdpSender(ws);
const openPromise = new Promise<void>((resolve, reject) => {
ws.once("open", () => resolve());
ws.once("error", (err) => reject(err));
});
await openPromise;
try {
return await fn(send);
} catch (err) {
closeWithError(err instanceof Error ? err : new Error(String(err)));
throw err;
} finally {
try {
ws.close();
} catch {
// ignore
}
}
}
export async function captureScreenshotPng(opts: {
wsUrl: string;
fullPage?: boolean;
}): Promise<Buffer> {
return await captureScreenshot({
wsUrl: opts.wsUrl,
fullPage: opts.fullPage,
format: "png",
});
}
export async function captureScreenshot(opts: {
wsUrl: string;
fullPage?: boolean;
format?: "png" | "jpeg";
quality?: number; // jpeg only (0..100)
}): Promise<Buffer> {
return await withCdpSocket(opts.wsUrl, async (send) => {
await send("Page.enable");
let clip:
| { x: number; y: number; width: number; height: number; scale: number }
| undefined;
if (opts.fullPage) {
const metrics = (await send("Page.getLayoutMetrics")) as {
cssContentSize?: { width?: number; height?: number };
contentSize?: { width?: number; height?: number };
};
const size = metrics?.cssContentSize ?? metrics?.contentSize;
const width = Number(size?.width ?? 0);
const height = Number(size?.height ?? 0);
if (width > 0 && height > 0) {
clip = { x: 0, y: 0, width, height, scale: 1 };
}
}
const format = opts.format ?? "png";
const quality =
format === "jpeg"
? Math.max(0, Math.min(100, Math.round(opts.quality ?? 85)))
: undefined;
const result = (await send("Page.captureScreenshot", {
format,
...(quality !== undefined ? { quality } : {}),
fromSurface: true,
captureBeyondViewport: true,
...(clip ? { clip } : {}),
})) as { data?: string };
const base64 = result?.data;
if (!base64) throw new Error("Screenshot failed: missing data");
return Buffer.from(base64, "base64");
});
}
export async function createTargetViaCdp(opts: {
cdpPort: number;
url: string;
}): Promise<{ targetId: string }> {
const version = await fetchJson<{ webSocketDebuggerUrl?: string }>(
`http://127.0.0.1:${opts.cdpPort}/json/version`,
1500,
);
const wsUrl = String(version?.webSocketDebuggerUrl ?? "").trim();
if (!wsUrl) throw new Error("CDP /json/version missing webSocketDebuggerUrl");
return await withCdpSocket(wsUrl, async (send) => {
const created = (await send("Target.createTarget", { url: opts.url })) as {
targetId?: string;
};
const targetId = String(created?.targetId ?? "").trim();
if (!targetId)
throw new Error("CDP Target.createTarget returned no targetId");
return { targetId };
});
}
export type CdpRemoteObject = {
type: string;
subtype?: string;
value?: unknown;
description?: string;
unserializableValue?: string;
preview?: unknown;
};
export type CdpExceptionDetails = {
text?: string;
lineNumber?: number;
columnNumber?: number;
exception?: CdpRemoteObject;
stackTrace?: unknown;
};
export async function evaluateJavaScript(opts: {
wsUrl: string;
expression: string;
awaitPromise?: boolean;
returnByValue?: boolean;
}): Promise<{
result: CdpRemoteObject;
exceptionDetails?: CdpExceptionDetails;
}> {
return await withCdpSocket(opts.wsUrl, async (send) => {
await send("Runtime.enable").catch(() => {});
const evaluated = (await send("Runtime.evaluate", {
expression: opts.expression,
awaitPromise: Boolean(opts.awaitPromise),
returnByValue: opts.returnByValue ?? true,
userGesture: true,
includeCommandLineAPI: true,
})) as {
result?: CdpRemoteObject;
exceptionDetails?: CdpExceptionDetails;
};
const result = evaluated?.result;
if (!result) throw new Error("CDP Runtime.evaluate returned no result");
return { result, exceptionDetails: evaluated.exceptionDetails };
});
}
export type AriaSnapshotNode = {
ref: string;
role: string;
name: string;
value?: string;
description?: string;
backendDOMNodeId?: number;
depth: number;
};
type RawAXNode = {
nodeId?: string;
role?: { value?: string };
name?: { value?: string };
value?: { value?: string };
description?: { value?: string };
childIds?: string[];
backendDOMNodeId?: number;
};
function axValue(v: unknown): string {
if (!v || typeof v !== "object") return "";
const value = (v as { value?: unknown }).value;
if (typeof value === "string") return value;
if (typeof value === "number" || typeof value === "boolean") {
return String(value);
}
return "";
}
function formatAriaSnapshot(
nodes: RawAXNode[],
limit: number,
): AriaSnapshotNode[] {
const byId = new Map<string, RawAXNode>();
for (const n of nodes) {
if (n.nodeId) byId.set(n.nodeId, n);
}
// Heuristic: pick a root-ish node (one that is not referenced as a child), else first.
const referenced = new Set<string>();
for (const n of nodes) {
for (const c of n.childIds ?? []) referenced.add(c);
}
const root =
nodes.find((n) => n.nodeId && !referenced.has(n.nodeId)) ?? nodes[0];
if (!root?.nodeId) return [];
const out: AriaSnapshotNode[] = [];
const stack: Array<{ id: string; depth: number }> = [
{ id: root.nodeId, depth: 0 },
];
while (stack.length && out.length < limit) {
const popped = stack.pop();
if (!popped) break;
const { id, depth } = popped;
const n = byId.get(id);
if (!n) continue;
const role = axValue(n.role);
const name = axValue(n.name);
const value = axValue(n.value);
const description = axValue(n.description);
const ref = `ax${out.length + 1}`;
out.push({
ref,
role: role || "unknown",
name: name || "",
...(value ? { value } : {}),
...(description ? { description } : {}),
...(typeof n.backendDOMNodeId === "number"
? { backendDOMNodeId: n.backendDOMNodeId }
: {}),
depth,
});
const children = (n.childIds ?? []).filter((c) => byId.has(c));
for (let i = children.length - 1; i >= 0; i--) {
const child = children[i];
if (child) stack.push({ id: child, depth: depth + 1 });
}
}
return out;
}
export async function snapshotAria(opts: {
wsUrl: string;
limit?: number;
}): Promise<{ nodes: AriaSnapshotNode[] }> {
const limit = Math.max(1, Math.min(2000, Math.floor(opts.limit ?? 500)));
return await withCdpSocket(opts.wsUrl, async (send) => {
await send("Accessibility.enable").catch(() => {});
const res = (await send("Accessibility.getFullAXTree")) as {
nodes?: RawAXNode[];
};
const nodes = Array.isArray(res?.nodes) ? res.nodes : [];
return { nodes: formatAriaSnapshot(nodes, limit) };
});
}
export async function snapshotDom(opts: {
wsUrl: string;
limit?: number;
maxTextChars?: number;
}): Promise<{
nodes: DomSnapshotNode[];
}> {
const limit = Math.max(1, Math.min(5000, Math.floor(opts.limit ?? 800)));
const maxTextChars = Math.max(
0,
Math.min(5000, Math.floor(opts.maxTextChars ?? 220)),
);
const expression = `(() => {
const maxNodes = ${JSON.stringify(limit)};
const maxText = ${JSON.stringify(maxTextChars)};
const nodes = [];
const root = document.documentElement;
if (!root) return { nodes };
const stack = [{ el: root, depth: 0, parentRef: null }];
while (stack.length && nodes.length < maxNodes) {
const cur = stack.pop();
const el = cur.el;
if (!el || el.nodeType !== 1) continue;
const ref = "n" + String(nodes.length + 1);
const tag = (el.tagName || "").toLowerCase();
const id = el.id ? String(el.id) : undefined;
const className = el.className ? String(el.className).slice(0, 300) : undefined;
const role = el.getAttribute && el.getAttribute("role") ? String(el.getAttribute("role")) : undefined;
const name = el.getAttribute && el.getAttribute("aria-label") ? String(el.getAttribute("aria-label")) : undefined;
let text = "";
try { text = String(el.innerText || "").trim(); } catch {}
if (maxText && text.length > maxText) text = text.slice(0, maxText) + "…";
const href = (el.href !== undefined && el.href !== null) ? String(el.href) : undefined;
const type = (el.type !== undefined && el.type !== null) ? String(el.type) : undefined;
const value = (el.value !== undefined && el.value !== null) ? String(el.value).slice(0, 500) : undefined;
nodes.push({
ref,
parentRef: cur.parentRef,
depth: cur.depth,
tag,
...(id ? { id } : {}),
...(className ? { className } : {}),
...(role ? { role } : {}),
...(name ? { name } : {}),
...(text ? { text } : {}),
...(href ? { href } : {}),
...(type ? { type } : {}),
...(value ? { value } : {}),
});
const children = el.children ? Array.from(el.children) : [];
for (let i = children.length - 1; i >= 0; i--) {
stack.push({ el: children[i], depth: cur.depth + 1, parentRef: ref });
}
}
return { nodes };
})()`;
const evaluated = await evaluateJavaScript({
wsUrl: opts.wsUrl,
expression,
awaitPromise: true,
returnByValue: true,
});
const value = evaluated.result?.value as unknown;
if (!value || typeof value !== "object") return { nodes: [] };
const nodes = (value as { nodes?: unknown }).nodes;
return { nodes: Array.isArray(nodes) ? (nodes as DomSnapshotNode[]) : [] };
}
export type DomSnapshotNode = {
ref: string;
parentRef: string | null;
depth: number;
tag: string;
id?: string;
className?: string;
role?: string;
name?: string;
text?: string;
href?: string;
type?: string;
value?: string;
};
export async function getDomText(opts: {
wsUrl: string;
format: "html" | "text";
maxChars?: number;
selector?: string;
}): Promise<{ text: string }> {
const maxChars = Math.max(
0,
Math.min(5_000_000, Math.floor(opts.maxChars ?? 200_000)),
);
const selectorExpr = opts.selector ? JSON.stringify(opts.selector) : "null";
const expression = `(() => {
const fmt = ${JSON.stringify(opts.format)};
const max = ${JSON.stringify(maxChars)};
const sel = ${selectorExpr};
const pick = sel ? document.querySelector(sel) : null;
let out = "";
if (fmt === "text") {
const el = pick || document.body || document.documentElement;
try { out = String(el && el.innerText ? el.innerText : ""); } catch { out = ""; }
} else {
const el = pick || document.documentElement;
try { out = String(el && el.outerHTML ? el.outerHTML : ""); } catch { out = ""; }
}
if (max && out.length > max) out = out.slice(0, max) + "\\n<!-- …truncated… -->";
return out;
})()`;
const evaluated = await evaluateJavaScript({
wsUrl: opts.wsUrl,
expression,
awaitPromise: true,
returnByValue: true,
});
const textValue = (evaluated.result?.value ?? "") as unknown;
const text =
typeof textValue === "string"
? textValue
: typeof textValue === "number" || typeof textValue === "boolean"
? String(textValue)
: "";
return { text };
}
export async function querySelector(opts: {
wsUrl: string;
selector: string;
limit?: number;
maxTextChars?: number;
maxHtmlChars?: number;
}): Promise<{
matches: QueryMatch[];
}> {
const limit = Math.max(1, Math.min(200, Math.floor(opts.limit ?? 20)));
const maxText = Math.max(
0,
Math.min(5000, Math.floor(opts.maxTextChars ?? 500)),
);
const maxHtml = Math.max(
0,
Math.min(20000, Math.floor(opts.maxHtmlChars ?? 1500)),
);
const expression = `(() => {
const sel = ${JSON.stringify(opts.selector)};
const lim = ${JSON.stringify(limit)};
const maxText = ${JSON.stringify(maxText)};
const maxHtml = ${JSON.stringify(maxHtml)};
const els = Array.from(document.querySelectorAll(sel)).slice(0, lim);
return els.map((el, i) => {
const tag = (el.tagName || "").toLowerCase();
const id = el.id ? String(el.id) : undefined;
const className = el.className ? String(el.className).slice(0, 300) : undefined;
let text = "";
try { text = String(el.innerText || "").trim(); } catch {}
if (maxText && text.length > maxText) text = text.slice(0, maxText) + "…";
const value = (el.value !== undefined && el.value !== null) ? String(el.value).slice(0, 500) : undefined;
const href = (el.href !== undefined && el.href !== null) ? String(el.href) : undefined;
let outerHTML = "";
try { outerHTML = String(el.outerHTML || ""); } catch {}
if (maxHtml && outerHTML.length > maxHtml) outerHTML = outerHTML.slice(0, maxHtml) + "…";
return {
index: i + 1,
tag,
...(id ? { id } : {}),
...(className ? { className } : {}),
...(text ? { text } : {}),
...(value ? { value } : {}),
...(href ? { href } : {}),
...(outerHTML ? { outerHTML } : {}),
};
});
})()`;
const evaluated = await evaluateJavaScript({
wsUrl: opts.wsUrl,
expression,
awaitPromise: true,
returnByValue: true,
});
const matches = evaluated.result?.value;
return { matches: Array.isArray(matches) ? (matches as QueryMatch[]) : [] };
}
export type QueryMatch = {
index: number;
tag: string;
id?: string;
className?: string;
text?: string;
value?: string;
href?: string;
outerHTML?: string;
};