Bash script for aggregating code-climate coverage stats across multiple parallel job runs on SemaphoreCI (e.g. with boosters)

report-coverage

#!/bin/bash

# Configuration via Environment Variables
# COVERAGE_BUCKET        name of s3 bucket where coverage files will be sent.
# AWS_ACCESS_KEY_ID
# AWS_SECRET_ACCESS_KEY  credentials for an IAM user with
#                        read/write permissions on the s3 bucket
# NON_COVERAGE_JOB_COUNT Number of semaphore tasks that do not generate coverage
#                        Defaults to 0

# Download the codeclimate reporter tool, make it executable.
curl -L https://codeclimate.com/downloads/test-reporter/test-reporter-latest-linux-amd64 > /home/runner/.rbenv/bin/cc-test-reporter
chmod +x /home/runner/.rbenv/bin/cc-test-reporter

# Where the remote coverage files will be stored. Ensures that coverage files for
# different projects, branches, and builds do not clobber one another.
REMOTE="s3://$COVERAGE_BUCKET/$SEMAPHORE_PROJECT_NAME/coverage/branch/$BRANCH_NAME/build/$SEMAPHORE_BUILD_NUMBER"

# Don't try and send coverage if none exists.
if [ -d coverage ]; then
  cc-test-reporter format-coverage \
    --output "coverage/codeclimate.$SEMAPHORE_CURRENT_JOB.json"
  # Push coverage stats from this job to central location
  aws s3 sync coverage/ $REMOTE
  # Remove the coverage dir after upload
  rm -rf coverage
fi

# The sum-coverage tasks needs to know how many different
# jobs will be contributing coverage stats. We can start 
# with the assumption that the number of semaphore threads
# defined by SEMAPHORE_THREAD_COUNT will be the number of
# jobs, but if there are some semaphore tasks that do not
# generate coverage stats, we can subtract those from the
# expected count.
NON_COVERAGE_JOB_COUNT=${NON_COVERAGE_JOB_COUNT:-0}
PARTS=$((SEMAPHORE_THREAD_COUNT-NON_COVERAGE_JOB_COUNT))

# Pull down all the coverages stats uploaded to s3 so far.
aws s3 sync $REMOTE coverage/

# Count the number of jobs that have been aggregated so far.
COMPLETED_PARTS=$(ls -l coverage/codeclimate.*.json | wc -l)

# If all the jobs have contributed their stats, then run the
# aggregation task and upload the coverage to code climate.
if [ $COMPLETED_PARTS -eq $PARTS ]; then
  cc-test-reporter sum-coverage --output - --parts $PARTS \
    coverage/codeclimate.*.json | \
    cc-test-reporter upload-coverage --input -
fi

This is awesome! Thank you!