Worklog for task "Integrate MODX frontend sessions into the haih-agent auth context"

Summary of Work

The task of reading existing MODX frontend sessions on the haih-agent side has been practically resolved and can be considered complete.

What Has Been Tested

On the new frontend side, it was possible to directly read MODX session data without a MODX bootstrap and without calling the legacy modSociety endpoint. This confirms the architectural feasibility of using MODX as the current session store, while parsing and further data processing are handled within haih-agent.

It also turned out that the main technical issue was not reading the session record from the database, but rather deserializing its PHP session payload in Node.js.

The Issue with php-serialize

php-serialize does not solve the problem directly because the MODX/PHP session in the format used is not simply the result of serialize($_SESSION). Therefore, the library is not suitable as a ready-made session decoder for the current case.

Using php-session-unserialize

To parse the session, the php-session-unserialize package was used. It correctly reads the PHP session format itself, but a library implementation quirk was discovered: PHP associative arrays inside readArray() are always created as JavaScript Arrays.

Essentially, the library does the following:

const resultArray = []
resultArray[key] = value

If a PHP array contains a string key, such as mgr, the result in JavaScript is an array with a named property (arr.mgr = ...). Such data is visible in console.log, but JSON.stringify and GraphQL only serialize indexed array elements, so the named properties are lost.

Practical example: a MODX session value like

modx.user.0.resourceGroups => { mgr: [] }

looked correct in the logs after initial parsing, but via GraphQL it turned into:

"modx.user.0.resourceGroups": []

Implemented Workaround

A recursive normalization of the result was added after unserialize():

function convertArraysToObjects(obj: unknown): unknown {
  if (Array.isArray(obj)) {
    const keys = Object.keys(obj)
    const hasStringKeys = keys.some((k) => isNaN(Number(k)))
    if (hasStringKeys) {
      const result: Record<string, unknown> = {}
      for (const key of keys) {
        result[key] = convertArraysToObjects(
          (obj as unknown as Record<string, unknown>)[key],
        )
      }
      return result
    }
    return obj.map(convertArraysToObjects)
  }
  if (obj && typeof obj === 'object') {
    const result: Record<string, unknown> = {}
    for (const [key, value] of Object.entries(obj)) {
      result[key] = convertArraysToObjects(value)
    }
    return result
  }
  return obj
}

After this, PHP associative arrays with named keys are converted to regular JS objects and pass correctly through JSON/GraphQL.

Result

After normalization, MODX session data is read correctly, including nested structures. In particular, branches such as the following are successfully retrieved:

{
  "modx.user.0.resourceGroups": {
    "mgr": []
  },
  "modx.user.0.attributes": {
    "web": {
      "modAccessContext": {
        "web": [
          {
            "principal": 0,
            "authority": "0",
            "policy": {
              "load": true,
              "formit": true,
              "formit_encryptions": false
            }
          }
        ]
      }
    }
  }
}

Data for other users/contexts, such as modx.user.1.attributes and ACL structures with a large set of manager permissions, are also visible in the session. This means the session payload is now fully available without losses during GraphQL serialization.

Limitations of the Current Solution

Theoretically, the current converter might ambiguously transform a PHP array with mixed numeric and string keys: if at least one string key is present, the entire JS Array turns into an Object. For standard MODX session structures, this is currently not critical; real data required by the project arrives correctly after normalization.

Therefore, at this stage, there is no need to write a custom PHP session parser or fork the library. If a real MODX session payload that the current scheme parses incorrectly is encountered later, it can be spun off into a separate technical task.

Scope of Completed Task

The goal of this task was specifically to prove the feasibility of reading and correctly deserializing an existing MODX frontend session on the haih-agent side. This goal has been achieved.

The logic for determining the specific current user based on session contents, selecting the required frontend context, retrieving additional user data, and subsequently building the auth/currentUser API constitutes the next application layer and, if necessary, should be structured separately.