puppeteer/packages/puppeteer-core/src/common/ExecutionContext.ts
jrandolf f42336cf83
feat: separate puppeteer and puppeteer-core (#9023)
This PR moves the puppeteer source code into separate mono-repo packages:

- `puppeteer` and `puppeteer-core` are now separated into their own
packages.
- `puppeteer-core` has a new exports called `puppeteer-core/internal`
for internal usage.

Tests and various tools have been updated to accommodate the migration.
2022-10-05 14:17:03 +02:00

369 lines
11 KiB
TypeScript

/**
* Copyright 2017 Google Inc. All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import {Protocol} from 'devtools-protocol';
import {CDPSession} from './Connection.js';
import {IsolatedWorld} from './IsolatedWorld.js';
import {JSHandle} from './JSHandle.js';
import {LazyArg} from './LazyArg.js';
import {EvaluateFunc, HandleFor} from './types.js';
import {
createJSHandle,
getExceptionMessage,
isString,
valueFromRemoteObject,
} from './util.js';
/**
* @public
*/
export const EVALUATION_SCRIPT_URL = 'pptr://__puppeteer_evaluation_script__';
const SOURCE_URL_REGEX = /^[\040\t]*\/\/[@#] sourceURL=\s*(\S*?)\s*$/m;
/**
* Represents a context for JavaScript execution.
*
* @example
* A {@link Page} can have several execution contexts:
*
* - Each {@link Frame} of a {@link Page | page} has a "default" execution
* context that is always created after frame is attached to DOM. This context
* is returned by the {@link Frame.executionContext} method.
* - Each {@link https://developer.chrome.com/extensions | Chrome extensions}
* creates additional execution contexts to isolate their code.
*
* @remarks
* By definition, each context is isolated from one another, however they are
* all able to manipulate non-JavaScript resources (such as DOM).
*
* @remarks
* Besides pages, execution contexts can be found in
* {@link WebWorker | workers}.
*
* @internal
*/
export class ExecutionContext {
/**
* @internal
*/
_client: CDPSession;
/**
* @internal
*/
_world?: IsolatedWorld;
/**
* @internal
*/
_contextId: number;
/**
* @internal
*/
_contextName: string;
/**
* @internal
*/
constructor(
client: CDPSession,
contextPayload: Protocol.Runtime.ExecutionContextDescription,
world?: IsolatedWorld
) {
this._client = client;
this._world = world;
this._contextId = contextPayload.id;
this._contextName = contextPayload.name;
}
/**
* Evaluates the given function.
*
* @example
*
* ```ts
* const executionContext = await page.mainFrame().executionContext();
* const result = await executionContext.evaluate(() => Promise.resolve(8 * 7))* ;
* console.log(result); // prints "56"
* ```
*
* @example
* A string can also be passed in instead of a function:
*
* ```ts
* console.log(await executionContext.evaluate('1 + 2')); // prints "3"
* ```
*
* @example
* Handles can also be passed as `args`. They resolve to their referenced object:
*
* ```ts
* const oneHandle = await executionContext.evaluateHandle(() => 1);
* const twoHandle = await executionContext.evaluateHandle(() => 2);
* const result = await executionContext.evaluate(
* (a, b) => a + b,
* oneHandle,
* twoHandle
* );
* await oneHandle.dispose();
* await twoHandle.dispose();
* console.log(result); // prints '3'.
* ```
*
* @param pageFunction - The function to evaluate.
* @param args - Additional arguments to pass into the function.
* @returns The result of evaluating the function. If the result is an object,
* a vanilla object containing the serializable properties of the result is
* returned.
*/
async evaluate<
Params extends unknown[],
Func extends EvaluateFunc<Params> = EvaluateFunc<Params>
>(
pageFunction: Func | string,
...args: Params
): Promise<Awaited<ReturnType<Func>>> {
return await this.#evaluate(true, pageFunction, ...args);
}
/**
* Evaluates the given function.
*
* Unlike {@link ExecutionContext.evaluate | evaluate}, this method returns a
* handle to the result of the function.
*
* This method may be better suited if the object cannot be serialized (e.g.
* `Map`) and requires further manipulation.
*
* @example
*
* ```ts
* const context = await page.mainFrame().executionContext();
* const handle: JSHandle<typeof globalThis> = await context.evaluateHandle(
* () => Promise.resolve(self)
* );
* ```
*
* @example
* A string can also be passed in instead of a function.
*
* ```ts
* const handle: JSHandle<number> = await context.evaluateHandle('1 + 2');
* ```
*
* @example
* Handles can also be passed as `args`. They resolve to their referenced object:
*
* ```ts
* const bodyHandle: ElementHandle<HTMLBodyElement> =
* await context.evaluateHandle(() => {
* return document.body;
* });
* const stringHandle: JSHandle<string> = await context.evaluateHandle(
* body => body.innerHTML,
* body
* );
* console.log(await stringHandle.jsonValue()); // prints body's innerHTML
* // Always dispose your garbage! :)
* await bodyHandle.dispose();
* await stringHandle.dispose();
* ```
*
* @param pageFunction - The function to evaluate.
* @param args - Additional arguments to pass into the function.
* @returns A {@link JSHandle | handle} to the result of evaluating the
* function. If the result is a `Node`, then this will return an
* {@link ElementHandle | element handle}.
*/
async evaluateHandle<
Params extends unknown[],
Func extends EvaluateFunc<Params> = EvaluateFunc<Params>
>(
pageFunction: Func | string,
...args: Params
): Promise<HandleFor<Awaited<ReturnType<Func>>>> {
return this.#evaluate(false, pageFunction, ...args);
}
async #evaluate<
Params extends unknown[],
Func extends EvaluateFunc<Params> = EvaluateFunc<Params>
>(
returnByValue: true,
pageFunction: Func | string,
...args: Params
): Promise<Awaited<ReturnType<Func>>>;
async #evaluate<
Params extends unknown[],
Func extends EvaluateFunc<Params> = EvaluateFunc<Params>
>(
returnByValue: false,
pageFunction: Func | string,
...args: Params
): Promise<HandleFor<Awaited<ReturnType<Func>>>>;
async #evaluate<
Params extends unknown[],
Func extends EvaluateFunc<Params> = EvaluateFunc<Params>
>(
returnByValue: boolean,
pageFunction: Func | string,
...args: Params
): Promise<HandleFor<Awaited<ReturnType<Func>>> | Awaited<ReturnType<Func>>> {
const suffix = `//# sourceURL=${EVALUATION_SCRIPT_URL}`;
if (isString(pageFunction)) {
const contextId = this._contextId;
const expression = pageFunction;
const expressionWithSourceUrl = SOURCE_URL_REGEX.test(expression)
? expression
: expression + '\n' + suffix;
const {exceptionDetails, result: remoteObject} = await this._client
.send('Runtime.evaluate', {
expression: expressionWithSourceUrl,
contextId,
returnByValue,
awaitPromise: true,
userGesture: true,
})
.catch(rewriteError);
if (exceptionDetails) {
throw new Error(
'Evaluation failed: ' + getExceptionMessage(exceptionDetails)
);
}
return returnByValue
? valueFromRemoteObject(remoteObject)
: createJSHandle(this, remoteObject);
}
let functionText = pageFunction.toString();
try {
new Function('(' + functionText + ')');
} catch (error) {
// This means we might have a function shorthand. Try another
// time prefixing 'function '.
if (functionText.startsWith('async ')) {
functionText =
'async function ' + functionText.substring('async '.length);
} else {
functionText = 'function ' + functionText;
}
try {
new Function('(' + functionText + ')');
} catch (error) {
// We tried hard to serialize, but there's a weird beast here.
throw new Error('Passed function is not well-serializable!');
}
}
let callFunctionOnPromise;
try {
callFunctionOnPromise = this._client.send('Runtime.callFunctionOn', {
functionDeclaration: functionText + '\n' + suffix + '\n',
executionContextId: this._contextId,
arguments: await Promise.all(args.map(convertArgument.bind(this))),
returnByValue,
awaitPromise: true,
userGesture: true,
});
} catch (error) {
if (
error instanceof TypeError &&
error.message.startsWith('Converting circular structure to JSON')
) {
error.message += ' Recursive objects are not allowed.';
}
throw error;
}
const {exceptionDetails, result: remoteObject} =
await callFunctionOnPromise.catch(rewriteError);
if (exceptionDetails) {
throw new Error(
'Evaluation failed: ' + getExceptionMessage(exceptionDetails)
);
}
return returnByValue
? valueFromRemoteObject(remoteObject)
: createJSHandle(this, remoteObject);
async function convertArgument(
this: ExecutionContext,
arg: unknown
): Promise<Protocol.Runtime.CallArgument> {
if (arg instanceof LazyArg) {
arg = await arg.get();
}
if (typeof arg === 'bigint') {
// eslint-disable-line valid-typeof
return {unserializableValue: `${arg.toString()}n`};
}
if (Object.is(arg, -0)) {
return {unserializableValue: '-0'};
}
if (Object.is(arg, Infinity)) {
return {unserializableValue: 'Infinity'};
}
if (Object.is(arg, -Infinity)) {
return {unserializableValue: '-Infinity'};
}
if (Object.is(arg, NaN)) {
return {unserializableValue: 'NaN'};
}
const objectHandle = arg && arg instanceof JSHandle ? arg : null;
if (objectHandle) {
if (objectHandle.executionContext() !== this) {
throw new Error(
'JSHandles can be evaluated only in the context they were created!'
);
}
if (objectHandle.disposed) {
throw new Error('JSHandle is disposed!');
}
if (objectHandle.remoteObject().unserializableValue) {
return {
unserializableValue:
objectHandle.remoteObject().unserializableValue,
};
}
if (!objectHandle.remoteObject().objectId) {
return {value: objectHandle.remoteObject().value};
}
return {objectId: objectHandle.remoteObject().objectId};
}
return {value: arg};
}
}
}
const rewriteError = (error: Error): Protocol.Runtime.EvaluateResponse => {
if (error.message.includes('Object reference chain is too long')) {
return {result: {type: 'undefined'}};
}
if (error.message.includes("Object couldn't be returned by value")) {
return {result: {type: 'undefined'}};
}
if (
error.message.endsWith('Cannot find context with specified id') ||
error.message.endsWith('Inspected target navigated or closed')
) {
throw new Error(
'Execution context was destroyed, most likely because of a navigation.'
);
}
throw error;
};