bug: Capacitor androidBridge.postMessage converting null to "..."

[chriswep]

originally posted here but closed due to inactivity: #4746

the method safeStringify in

capacitor/android/capacitor/src/main/assets/native-bridge.js

Line 175 in 0429905

if (typeof v === 'object') {

does not account for null values when checking for circular references (null has the type object as well). therefore [10,null,null,null] is converted to [10,null,'...','...'] (as posted in the original issue).

bug was introduced here: 0429905#diff-8afda3e2bce7fb91a14a66d96d63a89f112b852cf39223e6f820a1575cbdafebR175

[Ionitron]

This issue may need more information before it can be addressed. In particular, it will need a reliable Code Reproduction that demonstrates the issue.

Please see the Contributing Guide for how to create a Code Reproduction.

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Ionitron 💙

[chriswep]

paste this into console (this is the method used to post data to native android):

        const safeStringify = (value) => {
            const seen = new Set();
            return JSON.stringify(value, (_k, v) => {
                if (seen.has(v)) {
                    return '...';
                }
                if (typeof v === 'object') {
                    seen.add(v);
                }
                return v;
            });
        };
        
        safeStringify([null,null]);
        
        // output: "[null,\"...\"]"

[jcesarmobile]

Sorry, I still need an app where it can be reproduced

[chriswep]

ok, someone posted one in the original issue: https://github.com/gabrielcursino/capacitor-sqlite-test

however i think you might save some time by just running the method directly, since it is obviously treating null values as circular object references. this is an issue wherever this method is used.

[jepiqueau]

@jcesarmobile @chriswep you can find the app to reproduce the issue https://github.com/jepiqueau/capacitor-sqlite-test.git

[jepiqueau]

@jcesarmobile @chriswep seems that if you modify in assets/native-bridge.js the constant safeStringify by

const safeStringify = (value) => {
    const seen = new Set();
    return JSON.stringify(value, (_k, v) => {
        if (typeof v === 'object') {
            seen.add(v);
        }
        return v;
    });
};

it works , but i do not know what is the impact of doing that on the rest of the code and what the reason to have these lines

                if (seen.has(v)) {
                    return '...';
                }

Hope this will help

[chriswep]

@jepiqueau the purpose of the method is to remove circular references in an object since JSON.stringify would throw an error otherwise. with your change of safeStringify, circular refs stay in the object, making the method basically the same as JSON.stringify. The correct fix of the method is to replace if (typeof v === 'object') with if (typeof v === 'object' && v !== null).

[jepiqueau]

@chriswep your proposed fix is working Any progress status from @jcesaremobile

[emirtb]

same problem, two days lost ... and there is no way to solve it because it is the base framework

[jepiqueau]

@emirtb I am sorry for this time lost but there is nothing I can do it is in the hands of the Ionic Capacitor team

[emirtb]

@jcesarmobile @chriswep seems that if you modify in assets/native-bridge.js the constant safeStringify by

const safeStringify = (value) => {
    const seen = new Set();
    return JSON.stringify(value, (_k, v) => {
        if (typeof v === 'object') {
            seen.add(v);
        }
        return v;
    });
};

it works , but i do not know what is the impact of doing that on the rest of the code and what the reason to have these lines

                if (seen.has(v)) {
                    return '...';
                }

Hope this will help

@jcesarmobile @chriswep seems that if you modify in assets/native-bridge.js the constant safeStringify by

const safeStringify = (value) => {
    const seen = new Set();
    return JSON.stringify(value, (_k, v) => {
        if (typeof v === 'object') {
            seen.add(v);
        }
        return v;
    });
};

it works , but i do not know what is the impact of doing that on the rest of the code and what the reason to have these lines

                if (seen.has(v)) {
                    return '...';
                }

Hope this will help

To modify this file as a workaround, where is it located? in the node_modules?

Thanks

[jepiqueau]

@elylucas @thomasvidas @chriswep Seems it is always there in 3.1.2 despite the Changelog.md core: Modify safeStringify to allow multiple null values (#4853) (854539b). If i look in https://github.com/ionic-team/capacitor/blob/main/android/capacitor/src/main/assets/native-bridge.js it is still

        const safeStringify = (value) => {
            const seen = new Set();
            return JSON.stringify(value, (_k, v) => {
                if (seen.has(v)) {
                    return '...';
                }
                if (typeof v === 'object') {
                    seen.add(v);
                }
                return v;
            });
        };

and not the proposed solution by @thomasvidas

[ionitron-bot]

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