get changed-modules-local

Overview

Command: r2r eac get changed-modules-local [module...] Purpose: Get modules requiring rebuild based on local build state Category: get

Description

Detects which modules need rebuilding by checking local build state cache. Unlike get changed-modules which checks git changes, this command uses build artifacts and timestamps to determine what needs rebuilding.

The command compares module source files against the last successful build state to identify:

Modules that have changed and need rebuilding
Modules that are up-to-date
Specific reasons why each module needs rebuilding
Whether this is a fresh build (no previous build state exists)

Syntax

r2r eac get changed-modules-local [module...]

Parameters

module... - Optional module monikers to check. If not specified, all modules are checked.

Output Format

JSON output includes:

{
  "modules": ["module1", "module2"],
  "up_to_date": ["module3", "module4"],
  "change_reasons": {
    "module1": "source files modified",
    "module2": "dependency changed"
  },
  "is_fresh_build": false,
  "detection_time": "2.5ms"
}

Examples

Check All Modules

# Get all modules requiring rebuild
r2r eac get changed-modules-local | jq '.'

Check Specific Modules

# Check only specific modules
r2r eac get changed-modules-local src-auth src-api

Extract Module Lists

# Get list of modules needing rebuild
r2r eac get changed-modules-local | jq -r '.modules[]'

# Get list of up-to-date modules
r2r eac get changed-modules-local | jq -r '.up_to_date[]'

# Check change reasons
r2r eac get changed-modules-local | jq '.change_reasons'

Build Only Changed Modules

# Build only modules that need it
CHANGED=$(r2r eac get changed-modules-local | jq -r '.modules[]')
if [ -n "$CHANGED" ]; then
  for module in $CHANGED; do
    r2r eac build $module
  done
fi

Conditional Build Logic

# Check if any modules need building
RESULT=$(r2r eac get changed-modules-local)
IS_FRESH=$(echo "$RESULT" | jq -r '.is_fresh_build')
CHANGED_COUNT=$(echo "$RESULT" | jq -r '.modules | length')

if [ "$IS_FRESH" = "true" ]; then
  echo "Fresh build - building all modules"
  r2r eac build
elif [ "$CHANGED_COUNT" -gt 0 ]; then
  echo "Building $CHANGED_COUNT changed modules"
  echo "$RESULT" | jq -r '.modules[]' | xargs -L1 r2r eac build
else
  echo "All modules up-to-date"
fi

Use Cases

Local Development

Use this command during local development to avoid unnecessary rebuilds:

# Only rebuild what changed since last build
r2r eac get changed-modules-local | jq -r '.modules[]' | xargs -L1 r2r eac build

Pre-Commit Hook

Integrate into pre-commit hooks to validate only affected modules:

# Validate only modules that changed locally
CHANGED=$(r2r eac get changed-modules-local | jq -r '.modules[]')
for module in $CHANGED; do
  r2r eac validate artifacts $module
done

Build Status Reporting

Report on build freshness and required work:

# Generate build status report
RESULT=$(r2r eac get changed-modules-local)
echo "Modules needing rebuild: $(echo "$RESULT" | jq -r '.modules | length')"
echo "Up-to-date modules: $(echo "$RESULT" | jq -r '.up_to_date | length')"
echo "$RESULT" | jq -r '.change_reasons | to_entries[] | "\(.key): \(.value)"'

Command	Purpose	Use When
`get changed-modules-local`	Modules needing rebuild based on build state	Local development, incremental builds
`get changed-modules`	Modules affected by git changes	Working with uncommitted changes
`get changed-modules-ci`	Modules needing rebuild in CI	CI/CD pipelines, comparing against base commit