Use go-fsimpl to read from datasources

.golangci.yml

@@ -33,7 +33,7 @@ linters:
     # - funlen
     # - gci
     # - gochecknoglobals
-    # - gochecknoinits
+    - gochecknoinits
     - gocognit
     - goconst
     - gocritic

aws/ec2meta.go

@@ -1,13 +1,15 @@
 package aws
 
 import (
+	"context"
 	"net/http"
 	"strings"
 
 	"github.com/aws/aws-sdk-go/aws"
 	"github.com/aws/aws-sdk-go/aws/ec2metadata"
 	"github.com/aws/aws-sdk-go/aws/session"
 	"github.com/hairyhenderson/gomplate/v4/env"
+	"github.com/hairyhenderson/gomplate/v4/internal/deprecated"
 )
 
 const (
@@ -38,6 +40,7 @@ func NewEc2Meta(options ClientOptions) *Ec2Meta {
 			config := aws.NewConfig()
 			config = config.WithHTTPClient(&http.Client{Timeout: options.Timeout})
 			if endpoint := env.Getenv("AWS_META_ENDPOINT"); endpoint != "" {
+				deprecated.WarnDeprecated(context.Background(), "Use AWS_EC2_METADATA_SERVICE_ENDPOINT instead of AWS_META_ENDPOINT")
 				config = config.WithEndpoint(endpoint)
 			}
 

context.go

@@ -22,9 +22,18 @@ func (c *tmplctx) Env() map[string]string {
 }
 
 // createTmplContext reads the datasources for the given aliases
-//
-//nolint:staticcheck
-func createTmplContext(_ context.Context, aliases []string, d *data.Data) (interface{}, error) {
+func createTmplContext(
+	ctx context.Context, aliases []string,
+	//nolint:staticcheck
+	d *data.Data,
+) (interface{}, error) {
+	// we need to inject the current context into the Data value, because
+	// the Datasource method may need it
+	// TODO: remove this before v4
+	if d != nil {
+		d.Ctx = ctx
+	}
+
 	var err error
 	tctx := &tmplctx{}
 	for _, a := range aliases {

context_test.go

@@ -6,7 +6,9 @@ import (
 	"os"
 	"testing"
 
+	"github.com/hairyhenderson/go-fsimpl"
 	"github.com/hairyhenderson/gomplate/v4/data"
+	"github.com/hairyhenderson/gomplate/v4/internal/datafs"
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
@@ -31,6 +33,11 @@ func TestCreateContext(t *testing.T) {
 	require.NoError(t, err)
 	assert.Empty(t, c)
 
+	fsmux := fsimpl.NewMux()
+	fsmux.Add(datafs.EnvFS)
+
+	ctx = datafs.ContextWithFSProvider(ctx, fsmux)
+
 	fooURL := "env:///foo?type=application/yaml"
 	barURL := "env:///bar?type=application/yaml"
 	uf, _ := url.Parse(fooURL)

crypto/pbkdf2.go

@@ -7,22 +7,23 @@ import (
 	"crypto/sha512"
 	"fmt"
 	"hash"
+	"sync"
 
 	"golang.org/x/crypto/pbkdf2"
 )
 
-var hashFuncs map[crypto.Hash]func() hash.Hash
+var hashFuncs = sync.OnceValue[map[crypto.Hash]func() hash.Hash](func() map[crypto.Hash]func() hash.Hash {
+	h := make(map[crypto.Hash]func() hash.Hash)
+	h[crypto.SHA1] = sha1.New
+	h[crypto.SHA224] = sha256.New224
+	h[crypto.SHA256] = sha256.New
+	h[crypto.SHA384] = sha512.New384
+	h[crypto.SHA512] = sha512.New
+	h[crypto.SHA512_224] = sha512.New512_224
+	h[crypto.SHA512_256] = sha512.New512_256
 
-func init() {
-	hashFuncs = make(map[crypto.Hash]func() hash.Hash)
-	hashFuncs[crypto.SHA1] = sha1.New
-	hashFuncs[crypto.SHA224] = sha256.New224
-	hashFuncs[crypto.SHA256] = sha256.New
-	hashFuncs[crypto.SHA384] = sha512.New384
-	hashFuncs[crypto.SHA512] = sha512.New
-	hashFuncs[crypto.SHA512_224] = sha512.New512_224
-	hashFuncs[crypto.SHA512_256] = sha512.New512_256
-}
+	return h
+})()
 
 // StrToHash - find a hash given a certain string
 func StrToHash(hash string) (crypto.Hash, error) {

data/datafuncs.go

@@ -0,0 +1,98 @@
+package data
+
+import (
+	"github.com/hairyhenderson/gomplate/v4/internal/parsers"
+)
+
+// temporary aliases for parser functions while I figure out if they need to be
+// exported from the internal parsers package
+
+// JSON - Unmarshal a JSON Object. Can be ejson-encrypted.
+//
+// Deprecated: will be removed in a future version of gomplate. If you have a
+// need for this, please open an issue!
+var JSON = parsers.JSON
+
+// JSONArray - Unmarshal a JSON Array
+//
+// Deprecated: will be removed in a future version of gomplate. If you have a
+// need for this, please open an issue!
+var JSONArray = parsers.JSONArray
+
+// YAML - Unmarshal a YAML Object
+//
+// Deprecated: will be removed in a future version of gomplate. If you have a
+// need for this, please open an issue!
+var YAML = parsers.YAML
+
+// YAMLArray - Unmarshal a YAML Array
+//
+// Deprecated: will be removed in a future version of gomplate. If you have a
+// need for this, please open an issue!
+var YAMLArray = parsers.YAMLArray
+
+// TOML - Unmarshal a TOML Object
+//
+// Deprecated: will be removed in a future version of gomplate. If you have a
+// need for this, please open an issue!
+var TOML = parsers.TOML
+
+// CSV - Unmarshal CSV
+//
+// Deprecated: will be removed in a future version of gomplate. If you have a
+// need for this, please open an issue!
+var CSV = parsers.CSV
+
+// CSVByRow - Unmarshal CSV in a row-oriented form
+//
+// Deprecated: will be removed in a future version of gomplate. If you have a
+// need for this, please open an issue!
+var CSVByRow = parsers.CSVByRow
+
+// CSVByColumn - Unmarshal CSV in a Columnar form
+//
+// Deprecated: will be removed in a future version of gomplate. If you have a
+// need for this, please open an issue!
+var CSVByColumn = parsers.CSVByColumn
+
+// ToCSV -
+//
+// Deprecated: will be removed in a future version of gomplate. If you have a
+// need for this, please open an issue!
+var ToCSV = parsers.ToCSV
+
+// ToJSON - Stringify a struct as JSON
+//
+// Deprecated: will be removed in a future version of gomplate. If you have a
+// need for this, please open an issue!
+var ToJSON = parsers.ToJSON
+
+// ToJSONPretty - Stringify a struct as JSON (indented)
+//
+// Deprecated: will be removed in a future version of gomplate. If you have a
+// need for this, please open an issue!
+var ToJSONPretty = parsers.ToJSONPretty
+
+// ToYAML - Stringify a struct as YAML
+//
+// Deprecated: will be removed in a future version of gomplate. If you have a
+// need for this, please open an issue!
+var ToYAML = parsers.ToYAML
+
+// ToTOML - Stringify a struct as TOML
+//
+// Deprecated: will be removed in a future version of gomplate. If you have a
+// need for this, please open an issue!
+var ToTOML = parsers.ToTOML
+
+// CUE - Unmarshal a CUE expression into the appropriate type
+//
+// Deprecated: will be removed in a future version of gomplate. If you have a
+// need for this, please open an issue!
+var CUE = parsers.CUE
+
+// ToCUE - Stringify a struct as CUE
+//
+// Deprecated: will be removed in a future version of gomplate. If you have a
+// need for this, please open an issue!
+var ToCUE = parsers.ToCUE