Introduction to gossamer.core

Gossamer is a micro web framework module for Clojure. The gossamer.core module combines the following:

• Bract modules with following dependencies
  • Clojure tools.cli
  • Clojure tools.namespace in DEV mode for REPL workflow
  • Ring for serving web resources
• Cambium (for structured logging)
  • Clojure tools.logging
  • SLF4j logging facade
  • Logback logging implementation
  • Cheshire for JSON codec
• Calfpath (for web routing)

Usage

Since gossamer.core builds upon bract.core and other Bract modules, you may check the provided context and config files for the keys being used. A quickstart usage is as follows:

lein new gossamer myapp
cd myapp

Inspect the generated web application, starting with the README.md file.

Context keys

Context key	Value type	Description
:gossamer/calfpath-routes	vector of maps	Calfpath route maps
:gossamer/route-wrappers	vector of fn/FQFN	Route wrapper functions (fn [routes context & more]) -> routes

Config keys

Config key	Value type	Description
"gossamer.routes.compile.options"	map	Compile options for Calfpath routes, see calfpath.route/compile-routes
"gossamer.inner.ping.enabled"	boolean	Add inner ping route for latency checks?
"gossamer.inner.ping.endpoint.uris"	vector of string	Vector of inner ping endpoint URIs
"gossamer.inner.ping.endpoint.body"	string	String body for inner ping response
"gossamer.inner.ping.content.type"	string	Content type for inner ping body
"app.version"	string	Application version
"app.hostname"	string	Application hostname

Provided default context/config

File name	Available to applications as	Description
logback-included.xml	gossamer/core/logback-included.xml	base Logback config
context.edn	gossamer/core/context.edn	default inducer context
webapp-context.edn	gossamer/core/webapp-context.edn	standard webapp context
webapp-context.dev.edn	gossamer/core/webapp-context.dev.edn	DEV mode webapp context
config.edn	gossamer/core/config.edn	default Gossamer config
config.logback.edn	gossamer/core/config.logback.edn	Logback standard config
config.logback.dev.edn	gossamer/core/config.logback.dev.edn	Logback DEV mode config