Add envresolve tool (#1030)

tools/envresolve/go.mod

@@ -0,0 +1,13 @@
+module github.com/smartcontractkit/chainlink-testing-framework/tools/envresolve
+
+go 1.22.5
+
+require (
+	github.com/smartcontractkit/chainlink-testing-framework v1.32.5-0.20240716133725-a3b8de948a76
+	github.com/spf13/cobra v1.8.1
+)
+
+require (
+	github.com/inconshreveable/mousetrap v1.1.0 // indirect
+	github.com/spf13/pflag v1.0.5 // indirect
+)

tools/envresolve/go.sum

@@ -0,0 +1,12 @@
+github.com/cpuguy83/go-md2man/v2 v2.0.4/go.mod h1:tgQtvFlXSQOSOSIRvRPT7W67SCa46tRHOmNcaadrF8o=
+github.com/inconshreveable/mousetrap v1.1.0 h1:wN+x4NVGpMsO7ErUn/mUI3vEoE6Jt13X2s0bqwp9tc8=
+github.com/inconshreveable/mousetrap v1.1.0/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
+github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
+github.com/smartcontractkit/chainlink-testing-framework v1.32.5-0.20240716133725-a3b8de948a76 h1:U3hc8y9ave4rTINBhqtlVJpgUftEfQq4GO8avP64H5M=
+github.com/smartcontractkit/chainlink-testing-framework v1.32.5-0.20240716133725-a3b8de948a76/go.mod h1:5MSx/ZFLZZCzovF0TZU28dy2XPGznlc/sa2pgUN/8D8=
+github.com/spf13/cobra v1.8.1 h1:e5/vxKd/rZsfSJMUX1agtjeTDf+qv1/JdBF8gg5k9ZM=
+github.com/spf13/cobra v1.8.1/go.mod h1:wHxEcudfqmLYa8iTfL+OuZPbBZkmvliBWKIezN3kD9Y=
+github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
+github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

tools/envresolve/main.go

@@ -0,0 +1,31 @@
+package main
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/spf13/cobra"
+
+	"github.com/smartcontractkit/chainlink-testing-framework/utils"
+)
+
+func main() {
+	var rootCmd = &cobra.Command{
+		Use:   "envresolve",
+		Short: "Resolve environment variables in a string. Example envresolve '{{ env.CHAINLINK_IMAGE }}'",
+		Run: func(cmd *cobra.Command, args []string) {
+			if len(args) < 1 {
+				fmt.Fprintln(cmd.OutOrStdout(), "Error: No input provided")
+				return
+			}
+			input := args[0]
+
+			fmt.Fprintln(cmd.OutOrStdout(), utils.MustResolveEnvPlaceholder(input))
+		},
+	}
+
+	if err := rootCmd.Execute(); err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+}

utils/env_vars.go

@@ -0,0 +1,30 @@
+package utils
+
+import (
+	"fmt"
+	"os"
+	"regexp"
+)
+
+// mustResolveEnvPlaceholder checks if the input string is an environment variable placeholder and resolves it.
+func MustResolveEnvPlaceholder(input string) string {
+	envVarName, hasEnvVar := LookupEnvVarName(input)
+	if hasEnvVar {
+		value, set := os.LookupEnv(envVarName)
+		if !set {
+			fmt.Fprintf(os.Stderr, "Error resolving '%s'. Environment variable '%s' not set or is empty\n", input, envVarName)
+			os.Exit(1)
+		}
+		return value
+	}
+	return input
+}
+
+func LookupEnvVarName(input string) (string, bool) {
+	re := regexp.MustCompile(`^{{ env\.([a-zA-Z_]+) }}$`)
+	matches := re.FindStringSubmatch(input)
+	if len(matches) > 1 {
+		return matches[1], true
+	}
+	return "", false
+}