hcl2_upgrade update (#10221)

* handle template_dir, pwd funcs, handle min_packer_version
* gotpl packer_version becomes hcl2 packer.version
* uuid becomes hcl2 uuidv4
* test code with emojis
* handle all cases were we cannot guess what the argument was
* handle clean_resource_name cases
* up docs

command/hcl2_upgrade.go

@@ -64,10 +64,19 @@ const (
 # once they also need to be in the same folder. 'packer inspect folder/'
 # will describe to you what is in that folder.
 
+# Avoid mixing go templating calls ( for example ` + "```{{ upper(`string`) }}```" + ` ) 
+# and HCL2 calls (for example '${ var.string_value_example }' ). They won't be
+# executed together and the outcome will be unknown.
+`
+	inputVarHeader = `
 # All generated input variables will be of 'string' type as this is how Packer JSON
 # views them; you can change their type later on. Read the variables type
 # constraints documentation
 # https://www.packer.io/docs/from-1.5/variables#type-constraints for more info.
+`
+
+	packerBlockHeader = `
+# See https://www.packer.io/docs/from-1.5/blocks/packer for more info
 `
 
 	sourcesHeader = `
@@ -112,10 +121,22 @@ func (c *HCL2UpgradeCommand) RunContext(buildCtx context.Context, cla *HCL2Upgra
 
 	core := hdl.(*CoreWrapper).Core
 	if err := core.Initialize(); err != nil {
-		c.Ui.Error(fmt.Sprintf("Initialization error, continuing: %v", err))
+		c.Ui.Error(fmt.Sprintf("Ignoring following initialization error: %v", err))
 	}
 	tpl := core.Template
 
+	// Packer section
+	if tpl.MinVersion != "" {
+		out.Write([]byte(packerBlockHeader))
+		fileContent := hclwrite.NewEmptyFile()
+		body := fileContent.Body()
+		packerBody := body.AppendNewBlock("packer", nil).Body()
+		packerBody.SetAttributeValue("required_version", cty.StringVal(fmt.Sprintf(">= %s", tpl.MinVersion)))
+		out.Write(fileContent.Bytes())
+	}
+
+	out.Write([]byte(inputVarHeader))
+
 	// Output variables section
 
 	variables := []*template.Variable{}
@@ -266,12 +287,29 @@ func (c *HCL2UpgradeCommand) RunContext(buildCtx context.Context, cla *HCL2Upgra
 	return 0
 }
 
+type UnhandleableArgumentError struct {
+	Call           string
+	Correspondance string
+	Docs           string
+}
+
+func (uc UnhandleableArgumentError) Error() string {
+	return fmt.Sprintf(`unhandled %q call:
+# there is no way to automatically upgrade the %[1]q call.
+# Please manually upgrade to %s
+# Visit %s for more infos.`, uc.Call, uc.Correspondance, uc.Docs)
+}
+
 // transposeTemplatingCalls executes parts of blocks as go template files and replaces
 // their result with their hcl2 variant. If something goes wrong the template
 // containing the go template string is returned.
 func transposeTemplatingCalls(s []byte) []byte {
 	fallbackReturn := func(err error) []byte {
-		return append([]byte(fmt.Sprintf("\n#could not parse template for following block: %q\n", err)), s...)
+		if strings.Contains(err.Error(), "unhandled") {
+			return append([]byte(fmt.Sprintf("\n# %s\n", err)), s...)
+		}
+
+		return append([]byte(fmt.Sprintf("\n# could not parse template for following block: %q\n", err)), s...)
 	}
 	funcMap := texttemplate.FuncMap{
 		"timestamp": func() string {
@@ -289,9 +327,71 @@ func transposeTemplatingCalls(s []byte) []byte {
 		"build": func(a string) string {
 			return fmt.Sprintf("${build.%s}", a)
 		},
+		"template_dir": func() string {
+			return fmt.Sprintf("${path.root}")
+		},
+		"pwd": func() string {
+			return fmt.Sprintf("${path.cwd}")
+		},
+		"packer_version": func() string {
+			return fmt.Sprintf("${packer.version}")
+		},
+		"uuid": func() string {
+			return fmt.Sprintf("${uuidv4()}")
+		},
+		"lower": func(_ string) (string, error) {
+			return "", UnhandleableArgumentError{
+				"lower",
+				"`lower(var.example)`",
+				"https://www.packer.io/docs/from-1.5/functions/string/lower",
+			}
+		},
+		"upper": func(_ string) (string, error) {
+			return "", UnhandleableArgumentError{
+				"upper",
+				"`upper(var.example)`",
+				"https://www.packer.io/docs/from-1.5/functions/string/upper",
+			}
+		},
+		"split": func(_, _ string, _ int) (string, error) {
+			return "", UnhandleableArgumentError{
+				"split",
+				"`split(separator, string)`",
+				"https://www.packer.io/docs/from-1.5/functions/string/split",
+			}
+		},
+		"replace": func(_, _, _ string, _ int) (string, error) {
+			return "", UnhandleableArgumentError{
+				"replace",
+				"`replace(string, substring, replacement)` or `regex_replace(string, substring, replacement)`",
+				"https://www.packer.io/docs/from-1.5/functions/string/replace or https://www.packer.io/docs/from-1.5/functions/string/regex_replace",
+			}
+		},
+		"replace_all": func(_, _, _ string) (string, error) {
+			return "", UnhandleableArgumentError{
+				"replace_all",
+				"`replace(string, substring, replacement)` or `regex_replace(string, substring, replacement)`",
+				"https://www.packer.io/docs/from-1.5/functions/string/replace or https://www.packer.io/docs/from-1.5/functions/string/regex_replace",
+			}
+		},
+		"clean_resource_name": func(_ string) (string, error) {
+			return "", UnhandleableArgumentError{
+				"clean_resource_name",
+				"use custom validation rules, `replace(string, substring, replacement)` or `regex_replace(string, substring, replacement)`",
+				"https://packer.io/docs/from-1.5/variables#custom-validation-rules" +
+					" , https://www.packer.io/docs/from-1.5/functions/string/replace" +
+					" or https://www.packer.io/docs/from-1.5/functions/string/regex_replace",
+			}
+		},
+		"build_name": func() string {
+			return fmt.Sprintf("${build.name}")
+		},
+		"build_type": func() string {
+			return fmt.Sprintf("${build.type}")
+		},
 	}
 
-	tpl, err := texttemplate.New("generated").
+	tpl, err := texttemplate.New("hcl2_upgrade").
 		Funcs(funcMap).
 		Parse(string(s))
 

command/test-fixtures/hcl2_upgrade_basic/expected.pkr.hcl

@@ -7,6 +7,15 @@
 # once they also need to be in the same folder. 'packer inspect folder/'
 # will describe to you what is in that folder.
 
+# Avoid mixing go templating calls ( for example ```{{ upper(`string`) }}``` ) 
+# and HCL2 calls (for example '${ var.string_value_example }' ). They won't be
+# executed together and the outcome will be unknown.
+
+# See https://www.packer.io/docs/from-1.5/blocks/packer for more info
+packer {
+  required_version = ">= 1.6.0"
+}
+
 # All generated input variables will be of 'string' type as this is how Packer JSON
 # views them; you can change their type later on. Read the variables type
 # constraints documentation
@@ -27,6 +36,12 @@ variable "aws_secret_key" {
   sensitive = true
 }
 
+variable "secret_account" {
+  type      = string
+  default   = "🤷"
+  sensitive = true
+}
+
 # "timestamp" template function replacement
 locals { timestamp = regex_replace(timestamp(), "[- TZ:]", "") }
 
@@ -77,14 +92,61 @@ build {
   sources = ["source.amazon-ebs.autogenerated_1"]
 
   provisioner "shell" {
-    inline      = ["echo ${var.secret_account}", "echo ${build.ID}", "echo ${build.SSHPrivateKey}", "sleep 100000"]
+    except      = ["amazon-ebs"]
+    inline      = ["echo ${var.secret_account}", "echo ${build.ID}", "echo ${build.SSHPublicKey} | head -c 14", "echo ${path.root} is not ${path.cwd}", "echo ${packer.version}", "echo ${uuidv4()}"]
     max_retries = "5"
-    only        = ["amazon-ebs"]
+  }
-    timeout     = "5s"
+
+  # template: hcl2_upgrade:2:38: executing "hcl2_upgrade" at <clean_resource_name>: error calling clean_resource_name: unhandled "clean_resource_name" call:
+  # there is no way to automatically upgrade the "clean_resource_name" call.
+  # Please manually upgrade to use custom validation rules, `replace(string, substring, replacement)` or `regex_replace(string, substring, replacement)`
+  # Visit https://packer.io/docs/from-1.5/variables#custom-validation-rules , https://www.packer.io/docs/from-1.5/functions/string/replace or https://www.packer.io/docs/from-1.5/functions/string/regex_replace for more infos.
+  provisioner "shell" {
+    inline = ["echo mybuild-{{isotime | clean_resource_name}}"]
+  }
+
+  # template: hcl2_upgrade:2:35: executing "hcl2_upgrade" at <lower>: error calling lower: unhandled "lower" call:
+  # there is no way to automatically upgrade the "lower" call.
+  # Please manually upgrade to `lower(var.example)`
+  # Visit https://www.packer.io/docs/from-1.5/functions/string/lower for more infos.
+  provisioner "shell" {
+    inline = ["echo {{ `SOMETHING` | lower }}"]
+  }
+
+  # template: hcl2_upgrade:2:35: executing "hcl2_upgrade" at <upper>: error calling upper: unhandled "upper" call:
+  # there is no way to automatically upgrade the "upper" call.
+  # Please manually upgrade to `upper(var.example)`
+  # Visit https://www.packer.io/docs/from-1.5/functions/string/upper for more infos.
+  provisioner "shell" {
+    inline = ["echo {{ `something` | upper }}"]
+  }
+
+  # template: hcl2_upgrade:2:21: executing "hcl2_upgrade" at <split `some-string` `-` 0>: error calling split: unhandled "split" call:
+  # there is no way to automatically upgrade the "split" call.
+  # Please manually upgrade to `split(separator, string)`
+  # Visit https://www.packer.io/docs/from-1.5/functions/string/split for more infos.
+  provisioner "shell" {
+    inline = ["echo {{ split `some-string` `-` 0 }}"]
+  }
+
+  # template: hcl2_upgrade:2:21: executing "hcl2_upgrade" at <replace_all `-` `/` build_name>: error calling replace_all: unhandled "replace_all" call:
+  # there is no way to automatically upgrade the "replace_all" call.
+  # Please manually upgrade to `replace(string, substring, replacement)` or `regex_replace(string, substring, replacement)`
+  # Visit https://www.packer.io/docs/from-1.5/functions/string/replace or https://www.packer.io/docs/from-1.5/functions/string/regex_replace for more infos.
+  provisioner "shell" {
+    inline = ["echo {{ replace_all `-` `/` build_name }}"]
+  }
+
+  # template: hcl2_upgrade:2:21: executing "hcl2_upgrade" at <replace `some-string` `-` `/` 1>: error calling replace: unhandled "replace" call:
+  # there is no way to automatically upgrade the "replace" call.
+  # Please manually upgrade to `replace(string, substring, replacement)` or `regex_replace(string, substring, replacement)`
+  # Visit https://www.packer.io/docs/from-1.5/functions/string/replace or https://www.packer.io/docs/from-1.5/functions/string/regex_replace for more infos.
+  provisioner "shell" {
+    inline = ["echo {{ replace `some-string` `-` `/` 1 }}"]
   }
   provisioner "shell-local" {
-    except  = ["amazon-ebs"]
     inline  = ["sleep 100000"]
+    only    = ["amazon-ebs"]
     timeout = "5s"
   }
   post-processor "amazon-import" {

command/test-fixtures/hcl2_upgrade_basic/input.json

@@ -1,5 +1,7 @@
 {
+    "min_packer_version": "1.6.0",
     "variables": {
+        "secret_account": "🤷",
         "aws_region": null,
         "aws_secret_key": "",
         "aws_access_key": ""
@@ -7,6 +9,7 @@
     "sensitive-variables": [
         "aws_secret_key",
         "aws_access_key",
+        "secret_account",
         "potato"
     ],
     "builders": [
@@ -62,21 +65,58 @@
     "provisioners": [
         {
             "type": "shell",
-            "only": [
+            "except": [
                 "amazon-ebs"
             ],
             "max_retries": 5,
-            "timeout": "5s",
             "inline": [
                 "echo {{ user  `secret_account` }}",
                 "echo {{ build `ID` }}",
-                "echo {{ build `SSHPrivateKey` }}",
+                "echo {{ build `SSHPublicKey` }} | head -c 14",
-                "sleep 100000"
+                "echo {{ template_dir }} is not {{ pwd }}",
+                "echo {{ packer_version }}",
+                "echo {{ uuid }}"
+            ]
+        },
+        {
+            "type": "shell",
+            "inline": [
+                "echo mybuild-{{isotime | clean_resource_name}}"
+            ]
+        },
+        {
+            "type": "shell",
+            "inline": [
+                "echo {{ `SOMETHING` | lower }}"
+            ]
+        },
+        {
+            "type": "shell",
+            "inline": [
+                "echo {{ `something` | upper }}"
+            ]
+        },
+        {
+            "type": "shell",
+            "inline": [
+                "echo {{ split `some-string` `-` 0 }}"
+            ]
+        },
+        {
+            "type": "shell",
+            "inline": [
+                "echo {{ replace_all `-` `/` build_name }}"
+            ]
+        },
+        {
+            "type": "shell",
+            "inline": [
+                "echo {{ replace `some-string` `-` `/` 1 }}"
             ]
         },
         {
             "type": "shell-local",
-            "except": [
+            "only": [
                 "amazon-ebs"
             ],
             "timeout": "5s",