Further improve prevent-fetch scriptlet

This commit is contained in:
Raymond Hill 2024-09-05 11:17:36 -04:00
parent 1dc09b6217
commit 60a009c530
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GPG key ID: 25E1490B761470C2

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@ -2129,6 +2129,7 @@ builtinScriptlets.push({
fn: noFetchIf,
dependencies: [
'generate-content.fn',
'proxy-apply.fn',
'safe-self.fn',
],
});
@ -2175,61 +2176,58 @@ function noFetchIf(
responseProps.type = { value: responseType };
}
}
self.fetch = new Proxy(self.fetch, {
apply: function(target, thisArg, args) {
const details = args[0] instanceof self.Request
? args[0]
: Object.assign({ url: args[0] }, args[1]);
if ( safe.logLevel > 1 ) {
safe.uboLog(logPrefix, `apply:\n\t${Object.entries(details).map(a => `${a[0]}: ${a[1]}`).join('\n\t')}`);
proxyApplyFn('fetch', function fetch(target, thisArg, args) {
const details = args[0] instanceof self.Request
? args[0]
: Object.assign({ url: args[0] }, args[1]);
let proceed = true;
try {
const props = new Map();
for ( const prop in details ) {
let v = details[prop];
if ( typeof v !== 'string' ) {
try { v = safe.JSON_stringify(v); }
catch(ex) { }
}
if ( typeof v !== 'string' ) { continue; }
props.set(prop, v);
}
let proceed = true;
try {
const props = new Map();
for ( const prop in details ) {
let v = details[prop];
if ( typeof v !== 'string' ) {
try { v = safe.JSON_stringify(v); }
catch(ex) { }
}
if ( typeof v !== 'string' ) { continue; }
props.set(prop, v);
}
if ( propsToMatch === '' && responseBody === '' ) {
const out = Array.from(props).map(a => `${a[0]}:${a[1]}`);
safe.uboLog(logPrefix, `Called: ${out.join('\n')}`);
return Reflect.apply(target, thisArg, args);
}
proceed = needles.length === 0;
for ( const { key, pattern } of needles ) {
if (
pattern.expect && props.has(key) === false ||
safe.testPattern(pattern, props.get(key)) === false
) {
proceed = true;
break;
}
}
} catch(ex) {
if ( safe.logLevel > 1 || propsToMatch === '' && responseBody === '' ) {
const out = Array.from(props).map(a => `${a[0]}:${a[1]}`);
safe.uboLog(logPrefix, `Called: ${out.join('\n')}`);
}
if ( proceed ) {
if ( propsToMatch === '' && responseBody === '' ) {
return Reflect.apply(target, thisArg, args);
}
return generateContentFn(responseBody).then(text => {
safe.uboLog(logPrefix, `Prevented with response "${text}"`);
const response = new Response(text, {
headers: {
'Content-Length': text.length,
}
});
const props = Object.assign(
{ url: { value: details.url } },
responseProps
);
safe.Object_defineProperties(response, props);
return response;
});
proceed = needles.length === 0;
for ( const { key, pattern } of needles ) {
if (
pattern.expect && props.has(key) === false ||
safe.testPattern(pattern, props.get(key)) === false
) {
proceed = true;
break;
}
}
} catch(ex) {
}
if ( proceed ) {
return Reflect.apply(target, thisArg, args);
}
return generateContentFn(responseBody).then(text => {
safe.uboLog(logPrefix, `Prevented with response "${text}"`);
const response = new Response(text, {
headers: {
'Content-Length': text.length,
}
});
const props = Object.assign(
{ url: { value: details.url } },
responseProps
);
safe.Object_defineProperties(response, props);
return response;
});
});
}