quartz/content/notes/continuous-integration.md

title	aliases	tags
continuous-integration	continuous integration, CI	cosc202

0.1 What is it

continuous --> is always happening integration --> connecting software components

• in contrast to ad hoc, occasional integration:

  • diverging component developmetnamy break integration
  • repaiing software may be expensive

• supports 'aglile' software dev

  • like test driven development, help catch issues early

• usually automated

0.2 Purposes

• checking code syntax
  • e.g., have CI compile the code and report errors
  • (local devs compilaer may be different from remote)
• checking semantics of code
• building docs
  • e.g., auto run javadoc
• running projects code tests
  • auto run JUnit, and report fails

0.3 Starting CI jobs

• from version control
  • e.g., every commit triggered CI jobs to run
  • starts on a push to server
• manually
• on a schedule

0.4 Runs asnychronously

• dont require devs to wait for completion

• common to run locally as well as on consistent standard environment

• other timescales

  • local checks as you commit
  • checks as you type
  • checks as you save

0.5 Output

since CI is asynchronous, its feedback is also

• e.g.,
  • web badges showing status
  • can send emails
  • messaging platform
    • e.g., slack, discord, teams
    • webhooks etc

git project websites usually provide logging interface,. They will watch scripts in virtual terminal and capture output from CI scripts

0.6 Github piplines

• a pipeline has multiple stages

  • e.g., test, build, deploy

• each stages has multiple jobs

  • e.g., JUnit, custom tests, etc

0.7 Yaml

• most Ci frameworks use YAML for their configuration
• structured text based formats
• python-like format or ≈JSON

0.8 configurationg from git repo

• CI config often via file in git top-level directory

• CI is version managed

• Gitlab pipeline specs go into .gitlab-ci.yaml:

  • shows command sequece to run for a jon, within a stage
  • output from commands is stored for a subsequent viewing
  • indicates what files 'artifacts' should be kept from jobs