From 87929be026a34a46d7f4f5fc640e3457711a9e9f Mon Sep 17 00:00:00 2001
From: Luka Vandervelden <lukc@upyum.com>
Date: Fri, 8 Nov 2019 14:36:59 +0100
Subject: [PATCH] Updating service definitions format.

THIS IS A BREAKING CHANGE

Hopefully, this change will make it easier to remove data on service
removal, but also to export and backup service data and to add
per-service system users.

A few obsolete service definitions have also been updated to the new
format.

Testing is still incomplete, you may want to wait a few commits before
using this.
---
 services/authd.spec               | 27 +++++------
 services/gitea.spec               | 26 ++++++----
 services/kanban.spec              |  8 +++
 services/kanband.yaml             | 11 -----
 services/nginx.spec               |  7 +--
 services/postgresql.spec          | 40 +++++++--------
 services/www.spec                 |  3 +-
 src/service/environment.cr        | 14 +++---
 src/service/service.cr            | 32 ++++++------
 src/service/service_definition.cr | 81 +++++++++++++++++++------------
 10 files changed, 133 insertions(+), 116 deletions(-)
 create mode 100644 services/kanban.spec
 delete mode 100644 services/kanband.yaml

diff --git a/services/authd.spec b/services/authd.spec
index 29238f4..6ebddb5 100644
--- a/services/authd.spec
+++ b/services/authd.spec
@@ -1,22 +1,17 @@
 name: authd
-command: authd -K ${SERVICE_ROOT}/jwt_key -u ${SERVICE_ROOT}/passwd -g ${SERVICE_ROOT}/group
-environment-variables:
-    - LD_LIBRARY_PATH=/usr/local/lib
+command: authd -K jwt_key -u passwd -g group
 user: authd
 provides: auth
-%pre-start
-   name: Creating IPC directory
-   unless-directory: /run/ipc
+
+%file /run/ipc
+   name: IPC directory
    command: install -d -m6777 /run/ipc
-%pre-start
-   name: Creating JWT key
-   unless-file: ${SERVICE_ROOT}/jwt_key
-   command: head -c 64 /dev/urandom | base64 > ${SERVICE_ROOT}/jwt_key
-%pre-start
+%file jwt_key
+   name: JWT key
+   creation-command: head -c 64 /dev/urandom | base64 > jwt_key
+%file passwd
    name: passwd file
-   unless-file: ${SERVICE_ROOT}/passwd
-   command: touch ${SERVICE_ROOT}/passwd
-%pre-start
+   command: touch passwd
+%file group
    name: group file
-   unless-file: ${SERVICE_ROOT}/group
-   command: touch ${SERVICE_ROOT}/group
+   command: touch group
diff --git a/services/gitea.spec b/services/gitea.spec
index 76f028d..8c290c9 100644
--- a/services/gitea.spec
+++ b/services/gitea.spec
@@ -1,15 +1,23 @@
-command: gitea -C . -w . -c ./custom/conf/app.ini
+command: gitea -C . -w . -c gitea.cfg
 consumes: postgresql, http?
 requires-domain: true
 ports: http
 
-%directory ${SERVICE_ROOT}/custom/conf
-	name: working directory
+#%directory ${SERVICE_ROOT}/custom/conf
+#	name: working directory
+#	configuration: true
 
-%configuration gitea.cfg ${SERVICE_ROOT}/custom/conf/app.ini
-
-%pre-start
-    name: gitea database creation
+%file db-is-setup
+    name: postgresql database
     # 'command' is run only if this directory doesn't exist
-    unless-file: ${SERVICE_ROOT}/db_is_setup
-    command: pg_create_user.sh create_user_and_db && touch ${SERVICE_ROOT}/db_is_setup
+    creation-command: pg_create_user.sh create_user_and_db && touch db-is-setup
+    deletion-command: pg_remove_user.sh bla bla bla && rm db-is-setup
+    export-command:   pg_export_user.sh bla bla bla # FIXME: Where/how does it export?
+
+# With syntaxic sugar.
+%configuration gitea.cfg
+
+#%database
+#	type: postgresql
+#	from-token: postgresql
+
diff --git a/services/kanban.spec b/services/kanban.spec
new file mode 100644
index 0000000..29bc408
--- /dev/null
+++ b/services/kanban.spec
@@ -0,0 +1,8 @@
+name: kanband
+command: kanband -k ${AUTHD_ROOT}/jwt_key -S data
+user: kanband
+consumes: auth
+
+%file data
+    name: storage directory
+    creation-command: mkdir -p data && chown kanband:kanband data
diff --git a/services/kanband.yaml b/services/kanband.yaml
deleted file mode 100644
index ead7565..0000000
--- a/services/kanband.yaml
+++ /dev/null
@@ -1,11 +0,0 @@
-name: kanband
-command: kanband -k /srv/%{ENVIRONMENT}/jwt_key -S /srv/%{ENVIRONMENT}/kanban
-user: kanban
-environment-variables:
-    - LD_LIBRARY_PATH=/usr/local/lib
-consumes:
-    - token: auth
-checks:
-    - name: storage directory creation
-      directory: /srv/%{ENVIRONMENT}/kanban
-      command: mkdir -p /srv/%{ENVIRONMENT}/kanban && chown kanban:kanban /srv/%{ENVIRONMENT}/kanban
diff --git a/services/nginx.spec b/services/nginx.spec
index f2e2985..5d26301 100644
--- a/services/nginx.spec
+++ b/services/nginx.spec
@@ -1,9 +1,6 @@
-command: nginx -c ${SERVICE_ROOT}/nginx.conf
+command: nginx -c nginx.conf
 consumes: http?
 provides: www, http
 ports: http=80, https=443
 
-%directory ${SERVICE_ROOT}/
-	name: working directory
-
-%configuration nginx.conf ${SERVICE_ROOT}/nginx.conf
+%configuration nginx.conf
diff --git a/services/postgresql.spec b/services/postgresql.spec
index eec8db8..a66adf3 100644
--- a/services/postgresql.spec
+++ b/services/postgresql.spec
@@ -1,32 +1,28 @@
 name: postgresql
 user: postgres
-command: postgres -D ${SERVICE_ROOT} -k /tmp/postgresql-${ENVIRONMENT}
+command: postgres -D ${SERVICE_ROOT}/db -k /tmp/postgresql-${ENVIRONMENT}
 #stop-command: kill -HUP ${PID}
 environment-variables:
-    - PGROOT=${SERVICE_ROOT}
+	- PGROOT=${SERVICE_ROOT}
 provides: postgresql
 ports: postgresql
 
-%pre-start
-    name: database directory creation
-    unless-directory: ${SERVICE_ROOT}
-    command: mkdir -p ${SERVICE_ROOT} && chown postgres:postgres ${SERVICE_ROOT}
+#%file db
+#    name: database directory
+#    command: mkdir -p db && chown postgres:postgres db
 
-%pre-start
-    name: database creation
-    unless-file: ${SERVICE_ROOT}/base
-    command: su - postgres -c "initdb --locale en_US.UTF-8 -D '${SERVICE_ROOT}'" && rm ${SERVICE_ROOT}/postgresql.conf
+%file db
+	name: database creation
+	creation-command: mkdir db && chown postgres:postgres db && su - postgres -c "initdb --locale en_US.UTF-8 -D '${SERVICE_ROOT}/db'" && rm db/postgresql.conf
+	#export-command: FIXME
 
-%pre-start
-    name: database configuration
-    # once this file is created, there is no need to perform the command
-    unless-file: ${SERVICE_ROOT}/postgresql.conf
-    # gen-config inherits its parameters from the environment
-    command: gen-config postgresql.conf ${SERVICE_ROOT}/postgresql.conf && chown postgres:postgres ${SERVICE_ROOT}/postgresql.conf
+%configuration db/postgresql.conf
+	# gen-config inherits its parameters from the environment
+	creation-command: gen-config postgresql.conf ${SERVICE_ROOT}/postgresql.conf && chown postgres:postgres ${SERVICE_ROOT}/postgresql.conf
 
-%pre-start
-    name: sockets directory
-    unless-directory: /tmp/postgresql-${ENVIRONMENT}
-    # FIXME: impose permissions
-    command: mkdir -p /tmp/postgresql-${ENVIRONMENT} && chown postgres:postgres /tmp/postgresql-${ENVIRONMENT}
-    # FIXME: add postgresql-pre-start-db-dir around here
+%file /tmp/${SERVICE_NAME}-${ENVIRONMENT}
+	name: sockets directory
+	unless-directory: /tmp/${SERVICE_NAME}-${ENVIRONMENT}
+	# FIXME: impose permissions
+	command: mkdir -p /tmp/${SERVICE_NAME}-${ENVIRONMENT} && chown postgres:postgres /tmp/${SERVICE_NAME}-${ENVIRONMENT}
+	# FIXME: add postgresql-pre-start-db-dir around here
diff --git a/services/www.spec b/services/www.spec
index d60fe9e..0ac03c0 100644
--- a/services/www.spec
+++ b/services/www.spec
@@ -2,5 +2,6 @@ command: none
 consumes: www
 requires-domain: true
 
-%directory ${SERVICE_ROOT}/
+%file www
 	name: data directory
+	creation-command: mkdir www
diff --git a/src/service/environment.cr b/src/service/environment.cr
index 2e1a53d..8002ee9 100644
--- a/src/service/environment.cr
+++ b/src/service/environment.cr
@@ -8,7 +8,7 @@ class Environment
 
 	getter name : String
 	getter type : Type = Type::Prefix
-	getter pre_start_hooks = Array(ServiceDefinition::Hook).new
+	getter files = Array(ServiceDefinition::FileDefinition).new
 
 	# The place we’ll put services’ data and configuration.
 	@root : String?
@@ -20,12 +20,14 @@ class Environment
 	def initialize(@name, type = "prefix")
 		@type = Type.parse type
 
-		@pre_start_hooks = Array(ServiceDefinition::Hook).new
+		@files = Array(ServiceDefinition::FileDefinition).new
 
 		# FIXME: Should this *really* be here?
-		@pre_start_hooks << ServiceDefinition::Hook.new "Creating data directory",
-			"mkdir -p /srv/${ENVIRONMENT} && chmod a+rwt /srv/${ENVIRONMENT}",
-			unless_directory: "/srv/${ENVIRONMENT}"
+		# FIXME: $ENVIRONMENT_ROOT
+		@files << ServiceDefinition::FileDefinition.new "/srv/${ENVIRONMENT}",
+			"environment root",
+			creation_command: "mkdir -p /srv/${ENVIRONMENT} && chmod a+rwt /srv/${ENVIRONMENT}",
+			deletion_command: "rmdir /srv/${ENVIRONMENT}"
 	end
 
 	def initialize(@name, specs : SpecParser)
@@ -36,7 +38,7 @@ class Environment
 		end
 
 		specs.sections.select(&.name.==("check")).each do |check|
-			@pre_start_hooks << ServiceDefinition::Hook.new check
+			@files << ServiceDefinition::FileDefinition.new check
 		end
 	end
 
diff --git a/src/service/service.cr b/src/service/service.cr
index 58e157a..d69ab4e 100644
--- a/src/service/service.cr
+++ b/src/service/service.cr
@@ -193,6 +193,7 @@ class Service
 	private def build_environment
 		env = {} of String => String
 
+		env["SERVICE_NAME"] = name
 		env["SERVICE_ROOT"] = root
 		env["SERVICE_ID"] = full_id
 		env["ENVIRONMENT"] = @environment.name
@@ -240,32 +241,33 @@ class Service
 		end
 	end
 
-	def pre_start_hooks
-		@environment.pre_start_hooks + @reference.pre_start_hooks
+	def files
+		@environment.files + @reference.files
 	end
 
 	def start(pid_dir : String, log_dir : String)
-		pre_start_hooks.each do |hook|
+		FileUtils.mkdir_p root
+
+		files.each do |file|
 			run_hook = false
 
-			hook.unless_file.try do |file|
-				file = evaluate file
-				run_hook = true if ! File.exists? file
+			next unless creation_command = file.creation_command
+
+			path = evaluate file.file_path
+			if path[0] != '/'
+				path = "#{root}/#{path}"
 			end
 
-			hook.unless_directory.try do |directory|
-				directory = evaluate directory
-				run_hook = true if ! Dir.exists? directory
-			end
+			run_hook = (!File.exists? path) || file.is_configuration?
 
-			unless run_hook
-				next
-			end
+			next unless run_hook
 
-			puts "  - #{hook.name}"
+			puts "  - Creating #{file.name}"
 
 			child = Process.fork do
-				Process.exec "sh", ["-c", hook.command],
+				Dir.cd root
+
+				Process.exec "sh", ["-c", creation_command],
 					output: Process::Redirect::Inherit,
 					error: Process::Redirect::Inherit,
 					env: build_environment
diff --git a/src/service/service_definition.cr b/src/service/service_definition.cr
index 7cca6a7..954ad57 100644
--- a/src/service/service_definition.cr
+++ b/src/service/service_definition.cr
@@ -19,21 +19,40 @@ class ServiceDefinition
 		def initialize(@token)
 		end
 	end
-	struct Hook
+	struct FileDefinition
 		getter name : String
-		getter command : String
-		getter unless_directory : String?
-		getter unless_file : String?
+		getter file_path : String
 
-		def initialize(@name, @command, @unless_file = nil, @unless_directory = nil)
+		getter creation_command : String?
+		getter deletion_command : String?
+		getter export_command   : String?
+
+		@configuration = false
+
+		def initialize(@file_path, @name = @file_path,
+			@creation_command = nil,
+			@deletion_command = nil,
+			@export_command = nil,
+			@configuration = false)
 		end
 		def initialize(section : SpecParser::Section)
-			@name = section.content["name"].as_s
-			@command = section.content["command"].as_s
+			@file_path = section.options[0]
+			@name = section.content["name"]?.try(&.as_s) || @file_path
 
-			@unless_directory = section.content["unless-directory"]?
+			@creation_command = section.content["creation-command"]?
 				.try &.as_s
-			@unless_file = section.content["unless-file"]?.try &.as_s
+			@deletion_command = section.content["deletion-command"]?
+				.try &.as_s
+			@export_command   = section.content["export-command"]?
+				.try &.as_s
+
+			#@unless_directory = section.content["unless-directory"]?
+			#	.try &.as_s
+			#@unless_file = section.content["unless-file"]?.try &.as_s
+		end
+
+		def is_configuration?
+			@configuration
 		end
 	end
 
@@ -59,7 +78,7 @@ class ServiceDefinition
 	getter provides : String?
 	getter consumes : Array(Consumes)
 	getter environment_variables : Array(String)
-	getter pre_start_hooks : Array(Hook)
+	getter files : Array(FileDefinition)
 	getter provides : Array(Provides)
 	getter port_definitions : Array(PortDefinition)
 	getter non_runnable : Bool
@@ -92,39 +111,39 @@ class ServiceDefinition
 			STDERR.puts "warning: definition '#{@name}' has a 'requires-domain' entry with an invalid value"
 		end
 
-		@pre_start_hooks = Array(Hook).new
+		@files = Array(FileDefinition).new
 
 		sections.each do |section|
 			case section.name
-			when "pre-start"
-				@pre_start_hooks << Hook.new section
-			when "directory"
-				directory = section.options[0]?
-				name = section.content["name"]?.try &.as_s
-
-				if directory.nil?
-					STDERR.puts "warning: (#{@name}) %directory was not provided a path"
-					next
-				end
-
-				pre_start_hooks << Hook.new (name || "directory: #{directory}"),
-					"mkdir -p \"#{directory}\"",
-					unless_directory: directory
+			when "file", "directory"
+				@files << FileDefinition.new section
 			when "configuration"
 				options = section.options[0].split /[ \t]/
 
 				template = options[0]?
-				target = options[1]?
+
 				name = section.content["name"]?.try &.as_s
 
-				if template.nil? || target.nil?
-					STDERR.puts "warning: (#{@name}) %configuration received less than 2 options"
+				if template.nil?
+					STDERR.puts "warning: (#{@name}) %configuration wasn’t provided a target."
 					next
 				end
 
-				pre_start_hooks << Hook.new (name || "configuration file: #{template}"),
-					"gen-config \"#{template}\" \"#{target}\"",
-					unless_file: target
+				target = options[1]?
+				unless target
+					target = template
+					template = File.basename target
+				end
+
+				files << FileDefinition.new target, (name || target),
+					creation_command: "gen-config \"#{template}\" \"#{target}\"",
+					deletion_command: "rm \"#{target}\"",
+					configuration: true
+			when "database"
+				options = section.options[0].split /[ \t]/
+				type = options[0]? || section.content["type"]?.try &.as_s
+
+				# FIXME: %database is not currently implemented.
 			end
 		end
 	end