Enhancement for smooth commands update (#8)

README.md

@@ -22,6 +22,40 @@ provider "linux" {
     user = "root"
     password = "root"
 }
+
+resource "linux_directory" "directory" {
+    path = "/tmp/linux/dir"
+    owner = 1000
+    group = 1000
+    mode = "755"
+    overwrite = true
+    recycle_path = "/tmp/recycle"
+}
+
+resource "linux_file" "file" {
+    path = "/tmp/linux/file"
+    content = <<-EOF
+        hello world
+    EOF
+    owner = 1000
+    group = 1000
+    mode = "644"
+    overwrite = true
+    recycle_path = "/tmp/recycle"
+}
+
+resource "linux_script" "install_package" {
+    lifecycle_commands {
+        create = "apt update && apt install -y $PACKAGE_NAME=$PACKAGE_VERSION"
+        read = "apt-cache policy $PACKAGE_NAME | grep 'Installed:' | grep -v '(none)' | awk '{ print $2 }' | xargs | tr -d '\n'"
+        update = "apt update && apt install -y $PACKAGE_NAME=$PACKAGE_VERSION"
+        delete = "apt remove -y $PACKAGE_NAME"
+    }
+    environment = {
+        PACKAGE_NAME = "apache2"
+        PACKAGE_VERSION = "2.4.18-2ubuntu3.4"
+    }
+}
 ```
 
 Developing The Provider

docs/index.md

@@ -33,7 +33,7 @@ resource "linux_file" "file" {
     recycle_path = "/tmp/recycle"
 }
 
-resource "linux_script" "script" {
+resource "linux_script" "install_package" {
     lifecycle_commands {
         create = "apt update && apt install -y $PACKAGE_NAME=$PACKAGE_VERSION"
         read = "apt-cache policy $PACKAGE_NAME | grep 'Installed:' | grep -v '(none)' | awk '{ print $2 }' | xargs | tr -d '\n'"

docs/resources/script.md

@@ -5,7 +5,7 @@ Manage arbritrary resource by specifying scripts that will be executed remotely
 ## Example Usage
 
 ```hcl
-resource "linux_script" "script" {
+resource "linux_script" "install_package" {
     lifecycle_commands {
         create = "apt install -y $PACKAGE_NAME=$PACKAGE_VERSION"
         read = "apt-cache policy $PACKAGE_NAME | grep 'Installed:' | grep -v '(none)' | awk '{ print $2 }' | xargs | tr -d '\n'"
@@ -23,7 +23,7 @@ resource "linux_script" "script" {
 
 The following arguments are supported:
 
-- `lifecycle_commands` - (Required) Block that contains commands to be remotely executed respectively in Create|Read|Update|Delete phase. For complex commands, use [the file function](https://www.terraform.io/docs/configuration/functions/file.html).
+- `lifecycle_commands` - (Required) see [lifecycle_commands](#lifecycle_commands).
 - `triggers` - (Optional, string map) Attribute that will trigger resource recreation on changes just like the one in [null_resource](https://registry.terraform.io/providers/hashicorp/null/latest/docs/resources/resource#triggers). Default empty map.
 - `environment` - (Optional, string map) A list of linux environment that will be available in each `lifecycle_commands`. Default empty map.
 - `sensitive_environment` - (Optional, string map) Just like `environment` except they don't show up in log files. In case of duplication,  environment variables defined here will take precedence over the ones in `environment`. Default empty map.
@@ -32,12 +32,14 @@ The following arguments are supported:
 
 ### lifecycle_commands
 
-The following arguments are supported:
+Block that contains commands to be remotely executed respectively in **Create**,**Read**,**Update**, and **Delete** phase. For complex commands, use [the file function](https://www.terraform.io/docs/configuration/functions/file.html). The following arguments are supported:
+
+- `create` - (Required, string) Commands that will be executed in **Create** phase.
+- `read` - (Required, string) Commands that will be executed in Read phase and after execution of `create` or `update` commands. Terraform will record the output of these commands inside `output` attributes and trigger update/recreation when it changes (in **Read** phase only). If the result of running these commands produce an error, then it will give a signal for resource recreation. In this scenario, user have three options  before applying the changes: (1) do nothing since the resource has indeed become absent, (2) manually modifying the linux machine so no error will be produced in the next run, (3) update the commands. It is recommended that this operations does not do any kind of 'write' operation.
+- `update` - (Optional, string) Commands that will be executed in **Update** phase. Previous `output` are accessible from stdin. Omiting this will trigger resource recreation (**Delete** -> **Create**) each time terraform detect changes.
+- `delete` - (Required, string) Commands that will be executed in **Delete** phase.
 
-- `create` - (Required, string) Commands that will be execued in Create phase.
-- `read` - (Required, string) Commands that will be execued in Read phase and after execution of `create` or `update` commands. Terraform will record the output of these commands inside `output` attributes and trigger update/recreation when it changes. If the result of running these commands is empty string, the resource is considered as destroyed. If instead execution error is produced, then it will trigger resource recreation, unless the script is updated and `update` is not empty.
-- `update` - (Optional, string) Commands that will be execued in Update phase. Previous `output` are available from stdin. If `read` is updated, the next `terraform apply` will only execute the new `read` script. If `create` and/or `update` is the only things that are changed, then nothing is executed. Omiting this will disable Update phase and trigger resource recreation (Delete -> Create) each time terraform detect changes.
-- `delete` - (Required, string) Commands that will be execued in Delete phase.
+When any of the commands is updated, then nothing will be executed (except for the current `read` commands since it will always be executed before changes are detected). This is to mimic the behavior of an updated provider's logic, that is no previous logics will be executed. If at the same time another arguments is updated, then error will be thrown.
 
 ## Attribute Reference
 

linux/directory-resource_test.go

@@ -14,10 +14,9 @@ func TestAccLinuxDirectoryBasic(t *testing.T) {
 		Provider:  testAccProvider,
 		Directory: tNewTFMapDirectory().Without("owner", "group", "mode"),
 	}
-	conf2 := tfConf{
-		Provider:  testAccProvider,
-		Directory: conf1.Directory.Copy().With("mode", "700"),
-	}
+	conf2 := conf1.Copy(func(tc *tfConf) {
+		tc.Directory.With("mode", "700")
+	})
 	conf3 := tfConf{
 		Provider:  testAccProvider,
 		Directory: tNewTFMapDirectory(),
@@ -124,49 +123,46 @@ func testAccLinuxDirectoryBasicConfig(t *testing.T, conf tfConf) (s string) {
 	return
 }
 
-func TestAccLinuxDirectoryOverride(t *testing.T) {
+func TestAccLinuxDirectoryOverwrite(t *testing.T) {
 	conf1 := tfConf{
 		Provider:  testAccProvider,
 		Directory: tNewTFMapDirectory(),
 	}
-	conf2 := tfConf{
-		Provider:  testAccProvider,
-		Directory: conf1.Directory.Copy().With("overwrite", "true"),
-	}
+	conf2 := conf1.Copy(func(tc *tfConf) {
+		tc.Directory.With("overwrite", "true")
+	})
 	conf3 := tfConf{
 		Provider:  testAccProvider,
 		Directory: tNewTFMapDirectory(),
 		Extra:     tfmap{"path_previous": conf1.Directory["path"]},
 	}
-	conf4 := tfConf{
-		Provider:  testAccProvider,
-		Directory: conf3.Directory.Copy().With("overwrite", "true"),
-		Extra:     tfmap{"path_previous": conf1.Directory["path"]},
-	}
+	conf4 := conf3.Copy(func(tc *tfConf) {
+		tc.Directory.With("overwrite", "true")
+	})
 	resource.Test(t, resource.TestCase{
 		ExternalProviders: map[string]resource.ExternalProvider{"null": {}},
 		PreCheck:          testAccPreCheckConnection(t),
 		Providers:         testAccProviders,
 		Steps: []resource.TestStep{
 			{
-				Config:      testAccLinuxDirectoryeOverrideConfig(t, conf1),
+				Config:      testAccLinuxDirectoryeOverwriteConfig(t, conf1),
 				ExpectError: regexp.MustCompile(" exist"),
 			},
 			{
-				Config: testAccLinuxDirectoryeOverrideConfig(t, conf2),
+				Config: testAccLinuxDirectoryeOverwriteConfig(t, conf2),
 			},
 			{
-				Config:      testAccLinuxDirectoryeOverrideConfig(t, conf3),
+				Config:      testAccLinuxDirectoryeOverwriteConfig(t, conf3),
 				ExpectError: regexp.MustCompile(" exist"),
 			},
 			{
-				Config: testAccLinuxDirectoryeOverrideConfig(t, conf4),
+				Config: testAccLinuxDirectoryeOverwriteConfig(t, conf4),
 			},
 		},
 	})
 }
 
-func testAccLinuxDirectoryeOverrideConfig(t *testing.T, conf tfConf) (s string) {
+func testAccLinuxDirectoryeOverwriteConfig(t *testing.T, conf tfConf) (s string) {
 	tf := heredoc.Doc(`
 		provider "linux" {
 		    {{- .Provider.Serialize | nindent 4 }}

linux/file-resource_test.go

@@ -14,10 +14,9 @@ func TestAccLinuxFileBasic(t *testing.T) {
 		Provider: testAccProvider,
 		File:     tNewTFMapFile().Without("owner", "group", "mode"),
 	}
-	conf2 := tfConf{
-		Provider: testAccProvider,
-		File:     conf1.File.Copy().With("content", `"test"`),
-	}
+	conf2 := conf1.Copy(func(tc *tfConf) {
+		tc.File.With("content", `"test"`)
+	})
 	conf3 := tfConf{
 		Provider: testAccProvider,
 		File:     tNewTFMapFile(),
@@ -116,20 +115,17 @@ func TestAccLinuxFileOverride(t *testing.T) {
 		Provider: testAccProvider,
 		File:     tNewTFMapFile(),
 	}
-	conf2 := tfConf{
-		Provider: testAccProvider,
-		File:     conf1.File.Copy().With("overwrite", "true"),
-	}
+	conf2 := conf1.Copy(func(tc *tfConf) {
+		tc.File.With("overwrite", "true")
+	})
 	conf3 := tfConf{
 		Provider: testAccProvider,
 		File:     tNewTFMapFile(),
 		Extra:    tfmap{"path_previous": conf1.File["path"]},
 	}
-	conf4 := tfConf{
-		Provider: testAccProvider,
-		File:     conf3.File.Copy().With("overwrite", "true"),
-		Extra:    tfmap{"path_previous": conf1.File["path"]},
-	}
+	conf4 := conf3.Copy(func(tc *tfConf) {
+		tc.File.With("overwrite", "true")
+	})
 
 	resource.Test(t, resource.TestCase{
 		ExternalProviders: map[string]resource.ExternalProvider{"null": {}},