# Prow Job Extract Must-Gather
> Extract and decompress must-gather archives from Prow CI job artifacts, generating an interactive HTML file browser with filters
- Skill: `majiayu000/prow-job-extract-must-gather` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add majiayu000/prow-job-extract-must-gather`
- Raw SKILL.md: https://api.skillmd.com/api/skills/majiayu000/prow-job-extract-must-gather/raw
- Safety review: pending (external: skill-scanner PASS, skillspector WARNING)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Web & Frontend
- Author: majiayu000 (https://skillmd.com/u/majiayu000)
- Updated: 2026-09-09
- Page: https://skillmd.com/skills/majiayu000/prow-job-extract-must-gather
---
# Prow Job Extract Must-Gather
This skill extracts and decompresses must-gather archives from Prow CI job artifacts, automatically handling nested tar and gzip archives, and generating an interactive HTML file browser.
## When to Use This Skill
Use this skill when the user wants to:
- Extract must-gather archives from Prow CI job artifacts
- Avoid manually downloading and extracting nested archives
- Browse must-gather contents with an interactive HTML interface
- Search for specific files or file types in must-gather data
- Analyze OpenShift cluster state from CI test runs
## Prerequisites
Before starting, verify these prerequisites:
1. **gcloud CLI Installation**
- Check if installed: `which gcloud`
- If not installed, provide instructions for the user's platform
- Installation guide: https://cloud.google.com/sdk/docs/install
2. **gcloud Authentication (Optional)**
- The `test-platform-results` bucket is publicly accessible
- No authentication is required for read access
- Skip authentication checks
## Input Format
The user will provide:
1. **Prow job URL** - gcsweb URL containing `test-platform-results/`
- Example: `https://gcsweb-ci.apps.ci.l2s4.p1.openshiftapps.com/gcs/test-platform-results/logs/periodic-ci-openshift-release-master-ci-4.20-e2e-aws-ovn-techpreview/1965715986610917376/`
- URL may or may not have trailing slash
## Implementation Steps
### Step 1: Parse and Validate URL
1. **Extract bucket path**
- Find `test-platform-results/` in URL
- Extract everything after it as the GCS bucket relative path
- If not found, error: "URL must contain 'test-platform-results/'"
2. **Extract build_id**
- Search for pattern `/(\\d{10,})/` in the bucket path
- build_id must be at least 10 consecutive decimal digits
- Handle URLs with or without trailing slash
- If not found, error: "Could not find build ID (10+ digits) in URL"
3. **Extract prowjob name**
- Find the path segment immediately preceding build_id
- Example: In `.../periodic-ci-openshift-release-master-ci-4.20-e2e-aws-ovn-techpreview/1965715986610917376/`
- Prowjob name: `periodic-ci-openshift-release-master-ci-4.20-e2e-aws-ovn-techpreview`
4. **Construct GCS paths**
- Bucket: `test-platform-results`
- Base GCS path: `gs://test-platform-results/{bucket-path}/`
- Ensure path ends with `/`
### Step 2: Create Working Directory
1. **Check for existing extraction first**
- Check if `.work/prow-job-extract-must-gather/{build_id}/logs/` directory exists and has content
- If it exists with content:
- Use AskUserQuestion tool to ask:
- Question: "Must-gather already extracted for build {build_id}. Would you like to use the existing extraction or re-extract?"
- Options:
- "Use existing" - Skip to HTML report generation (Step 6)
- "Re-extract" - Continue to clean and re-download
- If user chooses "Re-extract":
- Remove all existing content: `rm -rf .work/prow-job-extract-must-gather/{build_id}/logs/`
- Also remove tmp directory: `rm -rf .work/prow-job-extract-must-gather/{build_id}/tmp/`
- This ensures clean state before downloading new content
- If user chooses "Use existing":
- Skip directly to Step 6 (Generate HTML Report)
2. **Create directory structure**
```bash
mkdir -p .work/prow-job-extract-must-gather/{build_id}/logs
mkdir -p .work/prow-job-extract-must-gather/{build_id}/tmp
```
- Use `.work/prow-job-extract-must-gather/` as the base directory (already in .gitignore)
- Use build_id as subdirectory name
- Create `logs/` subdirectory for extraction
- Create `tmp/` subdirectory for temporary files
- Working directory: `.work/prow-job-extract-must-gather/{build_id}/`
### Step 3: Download and Validate prowjob.json
1. **Download prowjob.json**
```bash
gcloud storage cp gs://test-platform-results/{bucket-path}/prowjob.json .work/prow-job-extract-must-gather/{build_id}/tmp/prowjob.json --no-user-output-enabled
```
2. **Parse and validate**
- Read `.work/prow-job-extract-must-gather/{build_id}/tmp/prowjob.json`
- Search for pattern: `--target=([a-zA-Z0-9-]+)`
- If not found:
- Display: "This is not a ci-operator job. The prowjob cannot be analyzed by this skill."
- Explain: ci-operator jobs have a --target argument specifying the test target
- Exit skill
3. **Extract target name**
- Capture the target value (e.g., `e2e-aws-ovn-techpreview`)
- Store for constructing must-gather path
### Step 4: Download Must-Gather Archive
1. **Construct must-gather path**
- GCS path: `gs://test-platform-results/{bucket-path}/artifacts/{target}/gather-must-gather/artifacts/must-gather.tar`
- Local path: `.work/prow-job-extract-must-gather/{build_id}/tmp/must-gather.tar`
2. **Download must-gather.tar**
```bash
gcloud storage cp gs://test-platform-results/{bucket-path}/artifacts/{target}/gather-must-gather/artifacts/must-gather.tar .work/prow-job-extract-must-gather/{build_id}/tmp/must-gather.tar --no-user-output-enabled
```
- Use `--no-user-output-enabled` to suppress progress output
- If file not found, error: "No must-gather archive found. Job may not have completed or gather-must-gather may not have run."
### Step 5: Extract and Process Archives
**IMPORTANT: Use the provided Python script `extract_archives.py` from the skill directory.**
**Usage:**
```bash
python3 plugins/prow-job/skills/prow-job-extract-must-gather/extract_archives.py \
.work/prow-job-extract-must-gather/{build_id}/tmp/must-gather.tar \
.work/prow-job-extract-must-gather/{build_id}/logs
```
**What the script does:**
1. **Extract must-gather.tar**
- Extract to `{build_id}/logs/` directory
- Uses Python's tarfile module for reliable extraction
2. **Rename long subdirectory to "content/"**
- Find subdirectory containing "-ci-" in the name
- Example: `registry-build09-ci-openshift-org-ci-op-m8t77165-stable-sha256-d1ae126eed86a47fdbc8db0ad176bf078a5edebdbb0df180d73f02e5f03779e0/`
- Rename to: `content/`
- Preserves all files and subdirectories
3. **Recursively process nested archives**
- Walk entire directory tree
- Find and process archives:
**For .tar.gz and .tgz files:**
```python
# Extract in place
with tarfile.open(archive_path, 'r:gz') as tar:
tar.extractall(path=parent_dir)
# Remove original archive
os.remove(archive_path)
```
**For .gz files (no tar):**
```python
# Gunzip in place
with gzip.open(gz_path, 'rb') as f_in:
with open(output_path, 'wb') as f_out:
shutil.copyfileobj(f_in, f_out)
# Remove original archive
os.remove(gz_path)
```
4. **Progress reporting**
- Print status for each extracted archive
- Count total files and archives processed
- Report final statistics
5. **Error handling**
- Skip corrupted archives with warning
- Continue processing other files
- Report all errors at the end
### Step 6: Generate HTML File Browser
**IMPORTANT: Use the provided Python script `generate_html_report.py` from the skill directory.**
**Usage:**
```bash
python3 plugins/prow-job/skills/prow-job-extract-must-gather/generate_html_report.py \
.work/prow-job-extract-must-gather/{build_id}/logs \
"{prowjob_name}" \
"{build_id}" \
"{target}" \
"{gcsweb_url}"
```
**Output:** The script generates `.work/prow-job-extract-must-gather/{build_id}/must-gather-browser.html`
**What the script does:**
1. **Scan directory tree**
- Recursively walk `{build_id}/logs/` directory
- Collect all files with metadata:
- Relative path from logs/
- File size (human-readable: KB, MB, GB)
- File extension
- Directory depth
- Last modified time
2. **Classify files**
- Detect file types based on extension:
- Logs: `.log`, `.txt`
- YAML: `.yaml`, `.yml`
- JSON: `.json`
- XML: `.xml`
- Certificates: `.crt`, `.pem`, `.key`
- Binaries: `.tar`, `.gz`, `.tgz`, `.tar.gz`
- Other
- Count files by type for statistics
3. **Generate HTML structure**
**Header Section:**
```html
```
**CSS Styling:**
- Use same dark theme as analyze-resource skill
- Modern, clean design with good contrast
- Responsive layout
- File type color coding
- Monospace fonts for paths
- Hover effects on file items
**JavaScript Interactivity:**
```javascript
// Multi-select file type filters
document.querySelectorAll('.filter-btn').forEach(btn => {
btn.addEventListener('click', function() {
// Toggle active state
// Apply filters
});
});
// Regex pattern filter
document.getElementById('pattern').addEventListener('input', function() {
const pattern = this.value;
if (pattern) {
const regex = new RegExp(pattern);
// Filter files matching regex
}
});
// Name search filter
document.getElementById('search').addEventListener('input', function() {
const query = this.value.toLowerCase();
// Filter files by name substring
});
// Combine all active filters
function applyFilters() {
// Show/hide files based on all active filters
}
```
4. **Statistics Section:**
```html
{total-files}
Total Files
{total-size}
Total Size
{log-count}
Log Files
{yaml-count}
YAML Files
```
5. **Write HTML to file**
- Script automatically writes to `.work/prow-job-extract-must-gather/{build_id}/must-gather-browser.html`
- Includes proper HTML5 structure
- All CSS and JavaScript are inline for portability
### Step 7: Present Results to User
1. **Display summary**
```
Must-Gather Extraction Complete
Prow Job: {prowjob-name}
Build ID: {build_id}
Target: {target}
Extraction Statistics:
- Total files: {file-count}
- Total size: {human-readable-size}
- Archives extracted: {archive-count}
- Log files: {log-count}
- YAML files: {yaml-count}
- JSON files: {json-count}
Extracted to: .work/prow-job-extract-must-gather/{build_id}/logs/
File browser generated: .work/prow-job-extract-must-gather/{build_id}/must-gather-browser.html
Open in browser to browse and search extracted files.
```
2. **Open report in browser**
- Detect platform and automatically open the HTML report in the default browser
- Linux: `xdg-open .work/prow-job-extract-must-gather/{build_id}/must-gather-browser.html`
- macOS: `open .work/prow-job-extract-must-gather/{build_id}/must-gather-browser.html`
- Windows: `start .work/prow-job-extract-must-gather/{build_id}/must-gather-browser.html`
- On Linux (most common for this environment), use `xdg-open`
3. **Offer next steps**
- Ask if user wants to search for specific files
- Explain that extracted files are available in `.work/prow-job-extract-must-gather/{build_id}/logs/`
- Mention that extraction is cached for faster subsequent browsing
## Error Handling
Handle these error scenarios gracefully:
1. **Invalid URL format**
- Error: "URL must contain 'test-platform-results/' substring"
- Provide example of valid URL
2. **Build ID not found**
- Error: "Could not find build ID (10+ decimal digits) in URL path"
- Explain requirement and show URL parsing
3. **gcloud not installed**
- Detect with: `which gcloud`
- Provide installation instructions for user's platform
- Link: https://cloud.google.com/sdk/docs/install
4. **prowjob.json not found**
- Suggest verifying URL and checking if job completed
- Provide gcsweb URL for manual verification
5. **Not a ci-operator job**
- Error: "This is not a ci-operator job. No --target found in prowjob.json."
- Explain: Only ci-operator jobs can be analyzed by this skill
6. **must-gather.tar not found**
- Warn: "Must-gather archive not found at expected path"
- Suggest: Job may not have completed or gather-must-gather may not have run
- Provide full GCS path that was checked
7. **Corrupted archive**
- Warn: "Could not extract {archive-path}: {error}"
- Continue processing other archives
- Report all errors in final summary
8. **No "-ci-" subdirectory found**
- Warn: "Could not find expected subdirectory to rename to 'content/'"
- Continue with extraction anyway
- Files will be in original directory structure
## Performance Considerations
1. **Avoid re-extracting**
- Check if `.work/prow-job-extract-must-gather/{build_id}/logs/` already has content
- Ask user before re-extracting
2. **Efficient downloads**
- Use `gcloud storage cp` with `--no-user-output-enabled` to suppress verbose output
3. **Memory efficiency**
- Process archives incrementally
- Don't load entire files into memory
- Use streaming extraction
4. **Progress indicators**
- Show "Downloading must-gather archive..." before gcloud command
- Show "Extracting must-gather.tar..." before extraction
- Show "Processing nested archives..." during recursive extraction
- Show "Generating HTML file browser..." before report generation
## Examples
### Example 1: Extract must-gather from periodic job
```
User: "Extract must-gather from this Prow job: https://gcsweb-ci.apps.ci.l2s4.p1.openshiftapps.com/gcs/test-platform-results/logs/periodic-ci-openshift-release-master-ci-4.20-e2e-aws-ovn-techpreview/1965715986610917376"
Output:
- Downloads must-gather.tar to: .work/prow-job-extract-must-gather/1965715986610917376/tmp/
- Extracts to: .work/prow-job-extract-must-gather/1965715986610917376/logs/
- Renames long subdirectory to: content/
- Processes 247 nested archives (.tar.gz, .tgz, .gz)
- Creates: .work/prow-job-extract-must-gather/1965715986610917376/must-gather-browser.html
- Opens browser with interactive file list (3,421 files, 234 MB)
```
## Tips
- Always verify gcloud prerequisites before starting (gcloud CLI must be installed)
- Authentication is NOT required - the bucket is publicly accessible
- Use `.work/prow-job-extract-must-gather/{build_id}/` directory structure for organization
- All work files are in `.work/` which is already in .gitignore
- The Python scripts handle all extraction and HTML generation - use them!
- Cache extracted files in `.work/prow-job-extract-must-gather/{build_id}/` to avoid re-extraction
- The HTML file browser supports regex patterns for powerful file filtering
- Extracted files can be opened directly from the HTML browser (links are relative)
## Important Notes
1. **Archive Processing:**
- The script automatically handles nested archives
- Original compressed files are removed after successful extraction
- Corrupted archives are skipped with warnings
2. **Directory Renaming:**
- The long subdirectory name (containing "-ci-") is renamed to "content/" for brevity
- Files within "content/" are NOT altered
- This makes paths more readable in the HTML browser
3. **File Type Detection:**
- File types are detected based on extension
- Common types are color-coded in the HTML browser
- All file types can be filtered
4. **Regex Pattern Filtering:**
- Users can enter regex patterns in the filter input
- Patterns match against full file paths
- Invalid regex patterns are ignored gracefully
5. **Working with Scripts:**
- All scripts are in `plugins/prow-job/skills/prow-job-extract-must-gather/`
- `extract_archives.py` - Extracts and processes archives
- `generate_html_report.py` - Generates interactive HTML file browser