runtimevar

Simple wrapper around the Go Cloud runtimevar package

Documentation

Example

package main

import (
	"context"
	"flag"
	"fmt"
	
	"github.com/sfomuseum/runtimevar"
	_ "gocloud.dev/runtimevar/awsparamstore"
	_ "gocloud.dev/runtimevar/constantvar"
	_ "gocloud.dev/runtimevar/filevar"
)

func main() {

	flag.Parse()

	ctx := context.Background()

	for _, uri := range flag.Args() {
		str_var, _ := runtimevar.StringVar(ctx, uri)
		fmt.Printf(str_var)
	}
}

Tools

$> make cli
go build -mod vendor -ldflags="-s -w" -o bin/runtimevar cmd/runtimevar/main.go

runtimevar

$> ./bin/runtimevar -h
Usage of ./bin/runtimevar:
  -timeout int
    	The maximum number of second in which a variable can be resolved. If 0 no timeout is applied.

$> go run cmd/runtimevar/main.go 'constant://?val=hello+world'
hello world

The following Go Cloud runtimevar services are supported by the runtimevar tool by default:

• AWS Parameter Store
• Local

AWS Parameter Store

It is possible to load runtime variables from AWS Parameter Store using aaronland/go-aws-session credential strings. For example:

$> go run cmd/runtimevar/main.go 'awsparamstore://hello-world?region=us-west-2&credentials=session'
hello world

Valid aaronland/go-aws-session credential strings are:

Credentials for AWS sessions are defined as string labels. They are:

Label	Description
env:	Read credentials from AWS defined environment variables.
iam:	Assume AWS IAM credentials are in effect.
{AWS_PROFILE_NAME}	Use the profile from the default AWS credentials location.
{AWS_CREDENTIALS_PATH}:{AWS_PROFILE_NAME}	Use the profile from a user-defined AWS credentials location.

See also

• https://gocloud.dev/howto/runtimevar
• https://github.com/aaronland/go-aws-session