ImportError+cannot+import+name+get+current+traceback+from+werkzeug+debug

Not specified by the original author.

TL;DR: your dash is too old for your werkzeug. Werkzeug 2.1 removed getcurrenttraceback and dash only fixed its import in 2.3.1. Upgrade dash, or pin werkzeug to 2.0.3.

The error

ImportError: cannot import name 'get_current_traceback' from 'werkzeug.debug.tbtools'

Fix it

1. Upgrade dash to a release with the fixed import:

   pip install -U dash

   Expected: installs dash 2.3.1 or newer.

2. Verify:

   python -c "import dash; print(dash.__version__)"

   Expected: imports cleanly and prints the version.

3. If you cannot upgrade dash, pin werkzeug instead:

   pip install "werkzeug==2.0.3"

   Expected: the old name exists again and dash imports.

When this applies

Use this when import dash raises this error and werkzeug is 2.1+.

When it does not apply

If the error names a different werkzeug symbol, check what replaced it. If you do not use dash at all, find which package imports the old name and upgrade that package.

Compatibility

dash below 2.3.1 with werkzeug 2.1+. dash 2.3.1+ works with modern werkzeug.

Root cause

Werkzeug 2.1 renamed the getcurrenttraceback function to the DebugTraceback class. dash imported the old name at module load, so any dash older than 2.3.1 breaks the moment werkzeug is upgraded past 2.0.x.

Edge cases

Pinning werkzeug at 2.0.3 can conflict with flask versions that need newer werkzeug; upgrading dash is the cleaner fix. Fresh virtualenvs avoid the half-upgraded state that usually triggers this.

The Plotly community forum thread (community.plotly.com/t/76605) reports ImportError: cannot import name 'getcurrenttraceback' from 'werkzeug.debug.tbtools' with dash 1.x and werkzeug 2.2.3. The verified answer: werkzeug 2.1 removed getcurrenttraceback (renamed to the DebugTraceback class), old dash imported the old name, and the fix is upgrading dash to 2.3.1 or later where plotly fixed the import (plotly/dash#1995), or pinning werkzeug to 2.0.3 as a workaround. Thread: https://community.plotly.com/t/dash-1-14-1-importerror-cannot-import-name-get-current-traceback-from-werkzeug-debug-tbtools/76605

Not specified by the original author.

ImportError: cannot import name 'requestctx_stack' from 'flask'

TL;DR

Flask removed the private requestctxstack in 2.3. Rewrite code that touches it to use the public proxies instead: flask.request, flask.g, and flask.currentapp cover nearly every use. Short term, pinning Flask below 2.3 also works.

The error

ImportError: cannot import name '_request_ctx_stack' from 'flask'

Fix it

1. Find usages: grep -rEn "requestctxstack|appctxstack" --include=*.py . Expected: A small list of files touching the private stacks.

2. Replace requestctxstack.top with the public equivalent. Most code wants flask.request, flask.session, or flask.g; app context access becomes flask.currentapp. Expected: The module imports and request handling works as before.

3. If a dependency does it, upgrade the dependency; most Flask extensions released 2.3-compatible versions. Expected: pip show [package] lists a version from mid-2023 or later.

4. Only as a stopgap: pip install 'flask<2.3'. Then schedule the rewrite, since the private API is gone for good. Expected: App boots on the pinned version.

When to use this

Use when upgrading to Flask 2.3+ and the traceback names requestctxstack or appctxstack imported from flask.

When NOT to use this

Not for 'working outside of request context' runtime errors, which are a different problem with a different fix.

Version notes

Private context stacks removed in Flask 2.3. Public proxies (request, g, current_app, session) are stable across 2.x and 3.x.

Why it happens

Flask 2.3 deleted its private context-stack objects as part of cleaning up the internals. Anything importing them, usually old extensions or copied snippets, fails at import time.

Edge cases

flask.globals still exposes the proxy objects; only the underscore-private stack names were removed, so most rewrites are one-liners.

Reported against Flask itself in pallets/flask#5347: importing requestctx_stack from flask fails on 2.3+. The maintainers point to the public request/app context proxies as the replacement, which is the documented migration path in the 2.3 changelog.

Not specified by the original author.

ImportError: cannot import name 'json' from 'itsdangerous'

TL;DR: itsdangerous 2.1+ removed the json shim that old Flask imports. Quick fix: pip install itsdangerous==2.0.1. Better fix: upgrade Flask to 2.0.1 or newer, which no longer needs it.

ImportError: cannot import name 'json' from 'itsdangerous'

The fix

1. Pin itsdangerous (fastest, no Flask upgrade):

pip install itsdangerous==2.0.1
python -c "from flask import Flask; print('ok')"

Success check: prints ok and your app starts.

2. Or upgrade Flask instead (cleaner long term):

pip install -U "Flask>=2.0.1"

Then remove the itsdangerous pin from requirements.txt.

3. Rebuild your Docker image from scratch after either change; a cached layer can keep the old itsdangerous.

Agent? Search Vectle for more: curl -s 'https://vectle.com/api/v1/search?q=itsdangerous+cannot+import+json'

When this applies

• Flask 1.1.x or 2.0.0 with itsdangerous 2.1+ installed.
• Traceback line reads from itsdangerous import json as _json.
• Docker builds that suddenly broke when a fresh pip install pulled a newer itsdangerous.

When it does NOT apply

• cannot import name 'TimedJSONWebSignatureSerializer': also a 2.0 removal, different name and fix.
• cannot import name 'soft_unicode' from 'markupsafe': the sibling Flask-era error; fix with markupsafe==2.0.1.

Tool and version compatibility

Flask 1.1.x/2.0.0 with itsdangerous>=2.1. Fixed pair: Flask>=2.0.1 with any itsdangerous>=2.0, or Flask 1.1.x with itsdangerous==2.0.1.

Why it happens

Flask used to do from itsdangerous import json as _json because itsdangerous bundled a json helper. itsdangerous 2.1 deleted it. Flask fixed their import in 2.0.1, so the error only bites old Flask + new itsdangerous combos, which is exactly what an unpinned pip install produces.

Edge cases

• pip install Flask==1.1.4 alone can trade this for the markupsafe soft_unicode error; pin markupsafe==2.0.1 with it.
• Check requirements.txt for bare itsdangerous with no pin and add the pin there, not just in the container.
• Itsdangerous 2.0.1 still gets security fixes contextually; upgrading Flask is the supported path.

The question was why Flask apps fail at startup with ImportError: cannot import name 'json' from 'itsdangerous'. The verified answer: itsdangerous 2.1 removed the bundled json import that Flask 1.1.x and 2.0.0 relied on, so the fix is to pin itsdangerous==2.0.1 or upgrade Flask past 2.0.1. Source: https://stackoverflow.com/questions/71189819/importerror-cannot-import-name-json-from-itsdangerous, thread so:71189819.