Failed to pull source: unable to determine source type of '/usr/share/snapcraft/extensions/ros2'.
Metadata
Current evaluation
Snapcraft 8 Docker image fails to resolve ros2 extension: get_extensions_data_dir() returns /usr/share/snapcraft/extensions but extensions are installed under site-packages/extensions. Untriaged, no maintainer activity in 374 days; same bug tracked in snapcraft-rocks#109.
Suggested action: needs triage
Reason: No labels, no comments, no maintainer response in 374 days, so this is untriaged. The bug is real and reproducible: get_extensions_data_dir() in extension.py:133 returns Path(sys.prefix)/share/snapcraft/extensions, which is correct for the snap (snap/snapcraft.yaml maps **/site-packages/extensions to share/snapcraft/extensions) but wrong in the Docker image where extensions land in site-packages/extensions. The identical issue is tracked in snapcraft-rocks#109 (open, acknowledged with a community workaround), confirming the root cause is in the Docker image build, not snapcraft core.
Impact:
55
Quick Win:
33.0
Staleness:
75
Complexity:
40
Confidence:
70
Support Request:
10
Issue body
### Bug Description
Snapcraft fails to find its own extensions:
```
2025-08-22T07:04:11.745Z [snapcraft] Initializing parts lifecycle
2025-08-22T07:04:13.827Z [snapcraft] **Failed to pull source: unable to determine source type of '/usr/share/snapcraft/extensions/ros2'.**
2025-08-22T07:04:13.828Z [snapcraft] Full execution log: '/root/.local/state/snapcraft/log/snapcraft-20250822-070411.734995.log'
2025-08-22T07:04:13.956Z [pebble] Service "snapcraft" stopped unexpectedly with code 1
```
extensions path is hardcoded here:
`usr/share/snapcraft/extensions`
https://github.com/canonical/snapcraft/blob/df4ec6775a28d4a345c93d9f83a1193c0abc1c9d/snapcraft/extensions/extension.py#L135
but in latest docker container for snapcraft 8, ghcr.io/canonical/snapcraft:8_core22 (24050a02f9fe)
extensions are located here:
`/usr/lib/python3.10/site-packages/extensions/ros2`
### To Reproduce
```bash
git clone https://github.com/snapcraft-docs/ros2-talker-listener-core22.git
cd ros2-talker-listener-core22
docker run -v $(pwd):/project ghcr.io/canonical/snapcraft:8_core22
```
### Environment
Ubuntu 22.04 LTS, Docker 28.3.1
### snapcraft.yaml
```yaml
name: ros2-talker-listener
version: '0.1'
summary: ROS 2 Talker/Listener Example
description: |
This example launches a ROS 2 talker and listener.
confinement: devmode
base: core22
parts:
ros-demos:
plugin: colcon
source: https://github.com/ros2/demos.git
source-branch: humble
source-subdir: demo_nodes_cpp
stage-packages: [ros-humble-ros2launch]
apps:
ros2-talker-listener:
command: opt/ros/humble/bin/ros2 launch demo_nodes_cpp talker_listener.launch.py
extensions: [ros2-humble]
```
### Relevant log output
```shell
docker run -v $(pwd):/project ghcr.io/canonical/snapcraft:8_core22
2025-08-22T07:04:05.252Z [pebble] Started daemon.
2025-08-22T07:04:05.284Z [pebble] POST /v1/services 16.330855ms 202 (http+unix)
2025-08-22T07:04:05.300Z [pebble] Service "snapcraft" starting: /bin/run-snapcraft.sh [ pack ]
2025-08-22T07:04:05.305Z [snapcraft]
2025-08-22T07:04:05.305Z [snapcraft] WARNING: apt does not have a stable CLI interface. Use with caution in scripts.
2025-08-22T07:04:05.305Z [snapcraft]
2025-08-22T07:04:05.777Z [snapcraft] Get:1 http://archive.ubuntu.com/ubuntu jammy InRelease [270 kB]
2025-08-22T07:04:05.922Z [snapcraft] Get:2 http://security.ubuntu.com/ubuntu jammy-security InRelease [129 kB]
2025-08-22T07:04:05.938Z [snapcraft] Get:3 http://archive.ubuntu.com/ubuntu jammy-updates InRelease [128 kB]
2025-08-22T07:04:05.981Z [snapcraft] Get:4 http://archive.ubuntu.com/ubuntu jammy-backports InRelease [127 kB]
2025-08-22T07:04:06.031Z [snapcraft] Get:5 http://archive.ubuntu.com/ubuntu jammy/restricted amd64 Packages [164 kB]
2025-08-22T07:04:06.080Z [snapcraft] Get:6 http://archive.ubuntu.com/ubuntu jammy/main amd64 Packages [1792 kB]
2025-08-22T07:04:06.249Z [snapcraft] Get:7 http://archive.ubuntu.com/ubuntu jammy/multiverse amd64 Packages [266 kB]
2025-08-22T07:04:06.272Z [snapcraft] Get:8 http://archive.ubuntu.com/ubuntu jammy/universe amd64 Packages [17.5 MB]
2025-08-22T07:04:06.298Z [snapcraft] Get:9 http://security.ubuntu.com/ubuntu jammy-security/multiverse amd64 Packages [48.5 kB]
2025-08-22T07:04:06.317Z [pebble] GET /v1/changes/1/wait 1.032101461s 200 (http+unix)
2025-08-22T07:04:06.318Z [pebble] Started default services with change 1.
2025-08-22T07:04:06.408Z [snapcraft] Get:10 http://security.ubuntu.com/ubuntu jammy-security/universe amd64 Packages [1271 kB]
2025-08-22T07:04:06.948Z [snapcraft] Get:11 http://security.ubuntu.com/ubuntu jammy-security/restricted amd64 Packages [5235 kB]
2025-08-22T07:04:07.779Z [snapcraft] Get:12 http://security.ubuntu.com/ubuntu jammy-security/main amd64 Packages [3253 kB]
2025-08-22T07:04:08.583Z [snapcraft] Get:13 http://archive.ubuntu.com/ubuntu jammy-updates/restricted amd64 Packages [5430 kB]
2025-08-22T07:04:09.285Z [snapcraft] Get:14 http://archive.ubuntu.com/ubuntu jammy-updates/universe amd64 Packages [1575 kB]
2025-08-22T07:04:09.452Z [snapcraft] Get:15 http://archive.ubuntu.com/ubuntu jammy-updates/multiverse amd64 Packages [75.9 kB]
2025-08-22T07:04:09.465Z [snapcraft] Get:16 http://archive.ubuntu.com/ubuntu jammy-updates/main amd64 Packages [3569 kB]
2025-08-22T07:04:09.856Z [snapcraft] Get:17 http://archive.ubuntu.com/ubuntu jammy-backports/main amd64 Packages [83.2 kB]
2025-08-22T07:04:09.860Z [snapcraft] Get:18 http://archive.ubuntu.com/ubuntu jammy-backports/universe amd64 Packages [35.2 kB]
2025-08-22T07:04:09.986Z [snapcraft] Fetched 40.9 MB in 5s (8818 kB/s)
2025-08-22T07:04:09.986Z [snapcraft] Reading package lists...
2025-08-22T07:04:10.683Z [snapcraft] Building dependency tree...
2025-08-22T07:04:10.813Z [snapcraft] Reading state information...
2025-08-22T07:04:10.827Z [snapcraft] 8 packages can be upgraded. Run 'apt list --upgradable' to see them.
2025-08-22T07:04:11.745Z [snapcraft] Initializing parts lifecycle
2025-08-22T07:04:13.827Z [snapcraft] Failed to pull source: unable to determine source type of '/usr/share/snapcraft/extensions/ros2'.
2025-08-22T07:04:13.828Z [snapcraft] Full execution log: '/root/.local/state/snapcraft/log/snapcraft-20250822-070411.734995.log'
2025-08-22T07:04:13.956Z [pebble] Service "snapcraft" stopped unexpectedly with code 1
2025-08-22T07:04:13.956Z [pebble] Service "snapcraft" on-failure action is "shutdown", triggering failure shutdown
2025-08-22T07:04:13.956Z [pebble] Server exiting! Reason: <nil>
```
### Additional context
_No response_
Evaluation history
| Date | Model | Scores | Action | Summary |
|---|---|---|---|---|
| qwen/qwen3.8-27b |
Impact:
55
Quick Win:
33.0
Staleness:
75
Complexity:
40
Confidence:
70
Support Request:
10
|
needs triage | Snapcraft 8 Docker image fails to resolve ros2 extension: get_extensions_data_dir() returns /usr/share/snapcraft/extensions but extensions are installed under site-packages/extensions. Untriaged, no maintainer activity in 374 days; same bug tracked in snapcraft-rocks#109. | |
| qwen/qwen3.6-35b-a3b |
Staleness:
95
Complexity:
40
Confidence:
85
Support Request:
10
|
close stale | Snapcraft fails to locate extensions due to hardcoded path mismatch in Docker container. No maintainer response, issue is 334 days old and completely inactive. | |
| qwen3.6-35b-a3b-mtp-q6 |
Staleness:
92
Complexity:
40
Confidence:
85
Support Request:
10
|
needs triage | Snapcraft fails to locate ROS2 extension due to hardcoded path mismatch in Docker container. Issue is 320 days old with no maintainer response or labels. | |
| qwen3.6-35b-a3b-mtp-q6 |
Staleness:
88
Complexity:
40
Confidence:
75
Support Request:
10
|
close stale | Snapcraft fails to locate ROS2 extensions due to a hardcoded path mismatch between the source code and the Docker container layout. The open issue has no comments or labels and requires triage and assignment. |
Update history
No update history recorded yet.
Related work
-
Duplicate Of:
canonical/snapcraft-rocks#109
(confidence 85%)
Identical title and error message; that issue is open, triaged, and has a community workaround but no official fix.
Related issues
| Issue | Project | State | Summary | Similarity |
|---|---|---|---|---|
| #109 Failed to pull source: unable to determine source type of '/usr/share/snapcraft/extensions/ros2' | snapcraft-rocks | open | Snapcraft 8 Docker image (ghcr.io/canonical/snapcraft:8_core22) fails to resolve ros2 extension: get_extensions_data_dir() returns /usr/share/snapcraft/extensions but extensions live in site-packages. Triaged, acknowledged by maintainer, workaround shared, still open. | |
| #1968303 remote-build: support for snap relative sources | snapcraft (launchpad) | open | Remote build fails when a part uses a snapcraft extension path ($SNAPCRAFT_EXTENSIONS_DIR/ros2) as its source, because the remote builder cannot determine the source type. Open since ~2021 with no labels, comments, or maintainer response. |