config

Overview ¶

Package config provides types for project configuration and loading config files from disk.

The files are loaded using the Loader, and then can be marshalled into json. The resulting json should be unmarshalled into a *hclpack.Body, which can then be decoded into the Root config.

A typical config file may look something like this:

project "example" {}

resource "aws_lambda_function" "func" {
  source = "./src"          # source code location

  handler = "index.handler" # attributes passed
  memory  = 512             # to resource
}

Source code ¶

If a resource specifies a source attribute, the source files from the directory are compressed into a source archive using the Compressor set on the Loader.

The source attribute is replaced with a source info block:

resource "aws_lambda_function" "func" {
  source ".tar.gz" {   # source extension
    sha = "b5bb9d8..." # sha256 hash of file contents
    md5 = "ERZsvZy..." # md5 hash of source archive
    len = 127          # source archive size in bytes
  }

  handler = "index.handler" # attributes passed
  memory  = 512             # to resource
}

Source() can be used to get a pointer to the source archive when source code is needed.

Except for the source, the entire body of a resource is specific to the resource type, set by the first label.

package main

import (
	"encoding/json"
	"log"

	"github.com/func/func/config"
	"github.com/hashicorp/hcl2/gohcl"
	"github.com/hashicorp/hcl2/hclpack"
)

var args = []string{"testdata/config"}

func main() {
	// Client

	// Find root, given user input
	project, err := config.FindProject(args[0])
	if err != nil {
		log.Fatal(err)
	}

	// Create a loader
	l := &config.Loader{}

	// Load config files from root
	cfg, diags := l.Load(project.RootDir)
	if diags.HasErrors() {
		log.Fatal(diags)
	}

	// Marshal config to json for transmission
	payload, err := json.Marshal(cfg)
	if err != nil {
		log.Fatal(err)
	}

	// Server

	// Parse payload
	var recv hclpack.Body
	if err := json.Unmarshal(payload, &recv); err != nil {
		log.Fatal(err)
	}

	// Decode config
	var root config.Root
	if err := gohcl.DecodeBody(&recv, nil, &root); err != nil {
		log.Fatal(err)
	}
}

Output: