Datadog Internship

report.md

Internship Report

App Configuration

• We can use different ways to configure an app: local/global variables, flags, environment variables, config files.
• Solutions like viper exist for go apps to combine those solutions all together.
• Should we use environment variables for app configuration?
  In my opinion, all the OS-dependent configuration options should be passed explicitly at the start of the application. Flags are the perfect way for that, because on the contrary of env variables, it's os-independent and explicit.

Here are all the reasons why we shouldn't use environment variables:

• Dynamically set: they can be set by other users, so we are not really sure of their value across the time.
• OS-dependent: risks of collision, for example if a variable X has a special meaning in one OS.
• Implicit dependencies: env variables are a form of dependency for our app, and experience has shown that dependencies should always be explicit.

-> Best practices:

• Separate static data, sensitive data and environment dependent data

JSON, YAML and TOML

• strictYAML proposes a simplified implementation of YAML spec.

Principle of least astonishment

• "If a necessary feature has a high astonishment factor, it may be necessary to redesign the feature." (wiki)

Semantic Versioning

• semver is a good practice to follow when releasing public faced software.