Python node failing after upgrade - import of standard library module disallowed

Questions
1

Describe the problem/error/question

Below python code started failing after upgrade to 1.123.4 from 1.122 (I believe).

import re
import zlib
import base64
import json

output = []

# Get the binary data from the first input item and decode from base64
#pdf_b64 = items[0]["binary"]["data"]["data"]
pdf_b64 = items[0]["json"]["data"]
#print(pdf_b64)
pdf = base64.b64decode(pdf_b64)
#print(pdf)

stream = re.compile(rb'/EmbeddedFile.*?FlateDecode.*?stream(.*?)endstream', re.S)

for s in stream.findall(pdf):
    s = s.strip(b'\r\n')
    try:
        decompressed = zlib.decompress(s)
        decoded = decompressed.decode('utf8')
        if 'Invoice' in decoded:
          output.append({"json": {"isdoc": decoded}})
    except:
        pass

return output

What is the error message (if any)?

Security violations detected

Line 1: Import of standard library module ‘re’ is disallowed. Allowed stdlib modules: none Line 2: Import of standard library module ‘zlib’ is disallowed. Allowed stdlib modules: none Line 3: Import of standard library module ‘base64’ is disallowed. Allowed stdlib modules: none Line 4: Import of standard library module ‘json’ is disallowed. Allowed stdlib modules: none

Error: Security violations detected at throwExecutionError (/usr/local/lib/node_modules/n8n/node_modules/.pnpm/n8n-nodes-base@file+packages+nodes-base_@aws-sdk+credential-providers@3.808.0_asn1.js@5_8da18263ca0574b0db58d4fefd8173ce/node_modules/n8n-nodes-base/nodes/Code/throw-execution-error.ts:11:9) at PythonTaskRunnerSandbox.runUsingIncomingItems (/usr/local/lib/node_modules/n8n/node_modules/.pnpm/n8n-nodes-base@file+packages+nodes-base_@aws-sdk+credential-providers@3.808.0_asn1.js@5_8da18263ca0574b0db58d4fefd8173ce/node_modules/n8n-nodes-base/nodes/Code/PythonTaskRunnerSandbox.ts:56:30) at processTicksAndRejections (node:internal/process/task_queues:105:5) at ExecuteContext.execute (/usr/local/lib/node_modules/n8n/node_modules/.pnpm/n8n-nodes-base@file+packages+nodes-base_@aws-sdk+credential-providers@3.808.0_asn1.js@5_8da18263ca0574b0db58d4fefd8173ce/node_modules/n8n-nodes-base/nodes/Code/Code.node.ts:171:12) at WorkflowExecute.executeNode (/usr/local/lib/node_modules/n8n/node_modules/.pnpm/n8n-core@file+packages+core_@opentelemetry+api@1.9.0_@opentelemetry+sdk-trace-base@1.30_ec37920eb95917b28efaa783206b20f3/node_modules/n8n-core/src/execution-engine/workflow-execute.ts:1045:8) at WorkflowExecute.runNode (/usr/local/lib/node_modules/n8n/node_modules/.pnpm/n8n-core@file+packages+core_@opentelemetry+api@1.9.0_@opentelemetry+sdk-trace-base@1.30_ec37920eb95917b28efaa783206b20f3/node_modules/n8n-core/src/execution-engine/workflow-execute.ts:1226:11) at /usr/local/lib/node_modules/n8n/node_modules/.pnpm/n8n-core@file+packages+core_@opentelemetry+api@1.9.0_@opentelemetry+sdk-trace-base@1.30_ec37920eb95917b28efaa783206b20f3/node_modules/n8n-core/src/execution-engine/workflow-execute.ts:1662:27 at /usr/local/lib/node_modules/n8n/node_modules/.pnpm/n8n-core@file+packages+core_@opentelemetry+api@1.9.0_@opentelemetry+sdk-trace-base@1.30_ec37920eb95917b28efaa783206b20f3/node_modules/n8n-core/src/execution-engine/workflow-execute.ts:2274:11

Please share your workflow

Information on your n8n setup

  • n8n version: 1.123.4 (Cloud)
2

Related bug report on github: Python Native Node: Import of standard library modules fails on 1.123 (regression) · Issue #22958 · n8n-io/n8n · GitHub

3

Another one opened here: https://github.com/n8n-io/n8n/issues/23072 and it was closed with explanation that Python node currently doesn’t allow imports due to security reasons.

4

Well, I think at this point you’ll have to look for another solution, like self-host, or maybe use AWS Lambda or something similar..

You could also try replicating what you’re doing in the code node with community nodes (if available) or even the built-in nodes, the code looks short, but I can’t fully understand the whole logic behind it..

5

Same error on self host

6

Another solution is to reimplement the decompression in JavaScript. I asked ChatGPT to reimplement logic in Python above in JavaScript without any imports of decompression libs and it did and it works! Incredible.

The decompression code has almost 300 lines and looks complex. I can paste it here if someone is interested.