TypeError: Cannot read properties of undefined (reading 'substr')

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1

Good day,

I get this TypeError: Cannot read properties of undefined (reading 'substr') error while I am running my tests in runner, but If I send them one by one error doesn’t occur.
Few days ago all was ok, but now I am getting this error.

Here are my functions:

//Save response field ([resPath]) value to variable ([varName])
function saveVar(varName, resPath) {
    try {
        const response = pm.response.json();
        console.log(`Attempting to save variable '${varName}' from path '${resPath}'`);

        // Retrieve the value from the response based on the resPath
        const value = getResponsePath(response, resPath);

        if (value !== undefined) {
            console.log(`Saving variable '${varName}' with value: ${value}`);
            pm.collectionVariables.set(varName, value);
        } else {
            console.error(`Error: Unable to save variable '${varName}' because the value at path '${resPath}' is undefined.`);
        }
    } catch (e) {
        console.error(`Error in saveVar: ${e.message}`);
    }
}


//Get and analyze path from response
function getResponsePath(response, resPath) {
    console.log("resPath:", resPath); // Log resPath before splitting
    console.log("response:", response); // Log response object

    if (!resPath) {
        console.error("Error: resPath is not defined");
        return undefined;
    }

    const segments = resPath.split('.');
    console.log("Segments:", segments);

    let value = response;
    for (const segment of segments) {
        if (value === undefined || value === null) {
            console.error(`Error: Value is ${value} at segment '${segment}'`);
            return undefined;
        }

        // Check for array index
        const match = segment.match(/(.+)\[(\d+)\]/);
        if (match) {
            const propertyName = match[1];
            const index = parseInt(match[2], 10);
            value = value[propertyName];
            if (Array.isArray(value)) {
                value = value[index];
            } else {
                console.error(`Error: Property ${propertyName} is not an array or does not exist.`);
                return undefined;
            }
        } else {
            value = value[segment];
        }

        if (value === undefined) {
            console.error(`Error: Unable to access property '${segment}' in response.`);
            return undefined;
        }
    }

    console.log(`Final value: ${value}`);
    return value;
}
2

Found an error - while sending body it was necessary to include variable in body into double “”. It is strange, because before all was working, but at least it works.

3

Now it causing this error in script without any body, just delete user request, again one by one is ok, but in runner it seems like runner doesn’t see my variable

4

Solution - Get variable in pre-request script. I don’t know why, but runner can not see my variables without this step

5

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