Merge pull request #1 from containeroo/toml

add support for toml files

Author: gi8lino

Makefile

@@ -0,0 +1,24 @@
+.PHONY: patch minor major tag
+
+# Find the latest tag (default to 0.0.0 if none found)
+LATEST_TAG := $(shell git tag --list 'v*' --sort=-v:refname | head -n 1)
+VERSION := $(shell echo $(LATEST_TAG) | sed 's/^v//' || echo "0.0.0")
+
+patch: ## Create a new patch release (x.y.Z+1)
+	@NEW_VERSION=$$(echo "$(VERSION)" | awk -F. '{printf "%d.%d.%d", $$1, $$2, $$3+1}') && \
+	git tag "v$${NEW_VERSION}" && \
+	echo "Tagged v$${NEW_VERSION}"
+
+minor: ## Create a new minor release (x.Y+1.0)
+	@NEW_VERSION=$$(echo "$(VERSION)" | awk -F. '{printf "%d.%d.0", $$1, $$2+1}') && \
+	git tag "v$${NEW_VERSION}" && \
+	echo "Tagged v$${NEW_VERSION}"
+
+major: ## Create a new major release (X+1.0.0)
+	@NEW_VERSION=$$(echo "$(VERSION)" | awk -F. '{printf "%d.0.0", $$1+1}') && \
+	git tag "v$${NEW_VERSION}" && \
+	echo "Tagged v$${NEW_VERSION}"
+
+tag: ## Show latest tag
+	@echo "Latest version: $(LATEST_TAG)"
+

README.md

@@ -1,11 +1,11 @@
 # Resolver Package
 
-The `resolver` package provides a flexible and extensible way to resolve configuration values from various sources including environment variables, files, JSON, YAML, INI, and key-value files. It uses a prefix-based system to identify which resolver to use and returns the resolved value or an error if something goes wrong.
+The `resolver` package provides a flexible and extensible way to resolve configuration values from various sources including environment variables, files, `JSON`, `YAML`, `INI`, `TOML` and key-value files. It uses a prefix-based system to identify which resolver to use and returns the resolved value or an error if something goes wrong.
 
 ## Installation
 
 ```bash
-go get github.com/yourusername/yourrepo/resolver
+go get github.com/containeroo/resolver/resolver
 ```
 
 ## Usage
@@ -22,6 +22,8 @@ The primary entry point is the `ResolveVariable` function. It takes a single str
   Example: `yaml:/config/app.yaml//server.port` returns `port` under `server` in `app.yaml`.It is also possible to indexing into arrays (e.g., `yaml:/config/app.yaml//servers.0.host`).
 - `ini`: – Resolves values from an INI file. Can specify a section and key, or just a key in the default section.
   Example: `ini:/config/app.ini//Section.Key` returns the value of `Key` under `Section`.
+- `toml`: – Resolves values from a TOML file.
+  Example: `toml:/config/app.toml//server.host` returns `host` under `server` in `app.toml`.
 - No prefix – Returns the value as-is, unchanged.
 
 ## Example
@@ -34,7 +36,7 @@ import (
     "log"
     "os"
 
-    "github.com/containeroo/portpatrol/resolver"
+    "github.com/containeroo/resolver"
 )
 
 func main() {

coverage.out

@@ -5,8 +5,13 @@ import (
 	"os"
 )
 
-// EnvResolver resolves values using environment variables.
-// Usage: "env:MY_VAR" -> returns value of MY_VAR
+// Resolves a value from environment variables.
+// The value after the prefix should be the name of the environment variable.
+// Example:
+// "env:MY_ENV_VAR"
+// would return the value of the MY_ENV_VAR environment variable.
+//
+// If the variable is not set, an error is returned.
 type EnvResolver struct{}
 
 func (r *EnvResolver) Resolve(value string) (string, error) {

env.go

@@ -8,9 +8,15 @@ import (
 	"strings"
 )
 
-// Resolves values from key = values files. The format can be:
-// "file:/config/app.txt//Key"
-// If no key is provided, returns the whole file.
+// Resolves a value by reading a key from a plain key=value text file.
+// The value after the prefix should be in the format "path/to/file.txt//Key"
+// If no key is provided, returns the entire file as a string.
+// Example:
+// "file:/config/app.txt//USERNAME"
+// would search for a line like "USERNAME = alice" and return "alice".
+//
+// Lines are matched by exact key name before the equals sign.
+// If no key is provided (no "//" present), returns the entire file as string.
 type KeyValueFileResolver struct{}
 
 func (f *KeyValueFileResolver) Resolve(value string) (string, error) {

file.go

@@ -0,0 +1,15 @@
+module github.com/containeroo/resolver
+
+go 1.24.2
+
+require (
+	github.com/pelletier/go-toml/v2 v2.2.4
+	github.com/stretchr/testify v1.10.0
+	gopkg.in/ini.v1 v1.67.0
+	gopkg.in/yaml.v3 v3.0.1
+)
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+)

go.mod

@@ -0,0 +1,14 @@
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/pelletier/go-toml/v2 v2.2.4 h1:mye9XuhQ6gvn5h28+VilKrrPoQVanw5PMw/TB0t5Ec4=
+github.com/pelletier/go-toml/v2 v2.2.4/go.mod h1:2gIqNv+qfxSVS7cM2xJQKtLSTLUE9V8t9Stt+h56mCY=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/testify v1.10.0 h1:Xv5erBjTwe/5IxqUQTdXv5kgmIvbHo3QQyRwhJsOfJA=
+github.com/stretchr/testify v1.10.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/ini.v1 v1.67.0 h1:Dgnx+6+nfE+IfzjUEISNeydPJh9AXNNsWbGP9KzCsOA=
+gopkg.in/ini.v1 v1.67.0/go.mod h1:pNLf8WUiyNEtQjuu5G5vTm06TEv9tsIgeAvK8hOrP4k=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

go.sum

@@ -8,6 +8,16 @@ import (
 	"gopkg.in/ini.v1"
 )
 
+// Resolves a value by loading an INI file and extracting a section.key pair.
+// The value after the prefix should be in the format "path/to/file.ini//Section.Key"
+// If no section is provided, the default section is used.
+// If no key is provided, returns the entire INI file as a string.
+// Example:
+// "ini:/config/app.ini//Database.User"
+// would load app.ini, locate the [Database] section, and return the value of User.
+//
+// Keys are navigated via "Section.Key" notation.
+// If no key is provided (no "//" present), returns the entire INI file as string.
 type INIResolver struct{}
 
 func (r *INIResolver) Resolve(value string) (string, error) {

ini.go

@@ -32,7 +32,7 @@ func (r *JSONResolver) Resolve(value string) (string, error) {
 		return strings.TrimSpace(string(data)), nil
 	}
 
-	var content map[string]interface{}
+	var content map[string]any
 	if err := json.Unmarshal(data, &content); err != nil {
 		return "", fmt.Errorf("failed to parse JSON in '%s': %w", filePath, err)
 	}

json.go

@@ -12,11 +12,12 @@ type Resolver interface {
 
 // Prefixes for different resolvers
 const (
-	envPrefix  = "env:"
-	jsonPrefix = "json:"
-	yamlPrefix = "yaml:"
-	iniPrefix  = "ini:"
-	filePrefix = "file:"
+	envPrefix  string = "env:"
+	filePrefix string = "file:"
+	iniPrefix  string = "ini:"
+	jsonPrefix string = "json:"
+	tomlPrefix string = "toml:"
+	yamlPrefix string = "yaml:"
 )
 
 // Global registry of resolvers
@@ -26,6 +27,7 @@ var resolvers = map[string]Resolver{
 	yamlPrefix: &YAMLResolver{},
 	iniPrefix:  &INIResolver{},
 	filePrefix: &INIResolver{},
+	tomlPrefix: &TOMLResolver{},
 }
 
 // ResolveVariable attempts to resolve the given value by checking for known prefixes.

resolver.go

@@ -0,0 +1,62 @@
+package resolver
+
+import (
+	"fmt"
+	"os"
+	"strings"
+
+	"github.com/pelletier/go-toml/v2"
+)
+
+// Resolves a value by loading a TOML file and extracting a nested key.
+// The value after the prefix should be in the format "path/to/file.toml//key1.key2.keyN"
+// If no key is provided, returns the entire TOML file as a string.
+// Example:
+// "toml:/config/app.toml//server.host"
+// would load app.toml, parse it as TOML, and then return the value at server.host.
+//
+// Keys are navigated via dot notation.
+// If no key is provided (no "//" present), returns the entire TOML file as string.
+type TOMLResolver struct{}
+
+func (r *TOMLResolver) Resolve(value string) (string, error) {
+	filePath, keyPath := splitFileAndKey(value)
+	filePath = os.ExpandEnv(filePath)
+
+	data, err := os.ReadFile(filePath)
+	if err != nil {
+		return "", fmt.Errorf("failed to read TOML file '%s': %w", filePath, err)
+	}
+
+	// Validate TOML syntax by decoding into a dummy struct
+	var validationTarget struct{}
+	if err := toml.Unmarshal(data, &validationTarget); err != nil {
+		return "", fmt.Errorf("failed to parse TOML in '%s': %w", filePath, err)
+	}
+
+	// Decode into navigable structure
+	var content map[string]any
+	if err := toml.Unmarshal(data, &content); err != nil {
+		return "", fmt.Errorf("failed to parse TOML in '%s': %w", filePath, err)
+	}
+
+	if keyPath == "" {
+		return strings.TrimSpace(string(data)), nil
+	}
+
+	val, err := navigateData(content, strings.Split(keyPath, "."))
+	if err != nil {
+		return "", fmt.Errorf("key path '%s' not found in TOML '%s': %w", keyPath, filePath, err)
+	}
+
+	if strVal, ok := val.(string); ok {
+		return strVal, nil
+	}
+
+	tomlVal, err := toml.Marshal(val)
+	if err != nil {
+		return "", fmt.Errorf("failed to encode TOML value: %w", err)
+	}
+
+	return strings.TrimSpace(string(tomlVal)), nil
+}