feat(cron): added automatic rebuilding of image; implemented builds

src/build/build.v

@@ -10,7 +10,7 @@ const container_build_dir = '/build'
 
 const build_image_repo = 'vieter-build'
 
-fn create_build_image(base_image string) ?string {
+pub fn create_build_image(base_image string) ?string {
 	commands := [
 		// Update repos & install required packages
 		'pacman -Syu --needed --noconfirm base-devel git'
@@ -53,12 +53,13 @@ fn create_build_image(base_image string) ?string {
 			break
 		}
 
-		// Wait for 5 seconds
+		time.sleep(1 * time.second)
-		time.sleep(5000000000)
 	}
 
 	// Finally, we create the image from the container
 	// As the tag, we use the epoch value
+	// TODO also add the base image's name into the image name to prevent
+	// conflicts.
 	tag := time.sys_mono_now().str()
 	image := docker.create_image_from_container(id, 'vieter-build', tag) ?
 	docker.remove_container(id) ?
@@ -66,6 +67,52 @@ fn create_build_image(base_image string) ?string {
 	return image.id
 }
 
+pub fn build_repo(address string, api_key string, base_image_id string, repo &git.GitRepo) ? {
+	build_arch := os.uname().machine
+
+	// TODO what to do with PKGBUILDs that build multiple packages?
+	commands := [
+		'git clone --single-branch --depth 1 --branch $repo.branch $repo.url repo',
+		'cd repo',
+		'makepkg --nobuild --nodeps',
+		'source PKGBUILD',
+		// The build container checks whether the package is already
+		// present on the server
+		'curl --head --fail $address/$repo.repo/$build_arch/\$pkgname-\$pkgver-\$pkgrel && exit 0',
+		'MAKEFLAGS="-j\$(nproc)" makepkg -s --noconfirm --needed && for pkg in \$(ls -1 *.pkg*); do curl -XPOST -T "\$pkg" -H "X-API-KEY: \$API_KEY" $address/$repo.repo/publish; done',
+	]
+
+	// We convert the list of commands into a base64 string, which then gets
+	// passed to the container as an env var
+	cmds_str := base64.encode_str(commands.join('\n'))
+
+	c := docker.NewContainer{
+		image: '$base_image_id'
+		env: ['BUILD_SCRIPT=$cmds_str', 'API_KEY=$api_key']
+		entrypoint: ['/bin/sh', '-c']
+		cmd: ['echo \$BUILD_SCRIPT | base64 -d | /bin/bash -e']
+		work_dir: '/build'
+		user: 'builder:builder'
+	}
+
+	id := docker.create_container(c) ?
+	docker.start_container(id) ?
+
+	// This loop waits until the container has stopped, so we can remove it after
+	for {
+		data := docker.inspect_container(id) ?
+
+		if !data.state.running {
+			break
+		}
+
+		// Wait for 5 seconds
+		time.sleep(1 * time.second)
+	}
+
+	docker.remove_container(id) ?
+}
+
 fn build(conf Config) ? {
 	build_arch := os.uname().machine
 
@@ -85,47 +132,7 @@ fn build(conf Config) ? {
 	image_id := create_build_image(conf.base_image) ?
 
 	for repo in filtered_repos {
-		// TODO what to do with PKGBUILDs that build multiple packages?
+		build_repo(conf.address, conf.api_key, image_id, repo) ?
-		commands := [
-			'git clone --single-branch --depth 1 --branch $repo.branch $repo.url repo',
-			'cd repo',
-			'makepkg --nobuild --nodeps',
-			'source PKGBUILD',
-			// The build container checks whether the package is already
-			// present on the server
-			'curl --head --fail $conf.address/$repo.repo/$build_arch/\$pkgname-\$pkgver-\$pkgrel && exit 0',
-			'MAKEFLAGS="-j\$(nproc)" makepkg -s --noconfirm --needed && for pkg in \$(ls -1 *.pkg*); do curl -XPOST -T "\$pkg" -H "X-API-KEY: \$API_KEY" $conf.address/$repo.repo/publish; done',
-		]
-
-		// We convert the list of commands into a base64 string, which then gets
-		// passed to the container as an env var
-		cmds_str := base64.encode_str(commands.join('\n'))
-
-		c := docker.NewContainer{
-			image: '$image_id'
-			env: ['BUILD_SCRIPT=$cmds_str', 'API_KEY=$conf.api_key']
-			entrypoint: ['/bin/sh', '-c']
-			cmd: ['echo \$BUILD_SCRIPT | base64 -d | /bin/bash -e']
-			work_dir: '/build'
-			user: 'builder:builder'
-		}
-
-		id := docker.create_container(c) ?
-		docker.start_container(id) ?
-
-		// This loop waits until the container has stopped, so we can remove it after
-		for {
-			data := docker.inspect_container(id) ?
-
-			if !data.state.running {
-				break
-			}
-
-			// Wait for 5 seconds
-			time.sleep(5000000000)
-		}
-
-		docker.remove_container(id) ?
 	}
 
 	// Finally, we remove the builder image

src/cron/cli.v

@@ -12,6 +12,7 @@ pub:
 	base_image              string = 'archlinux:base-devel'
 	max_concurrent_builds   int    = 1
 	api_update_frequency    int    = 15
+	image_rebuild_frequency int    = 1440
 	// Replicates the behavior of the original cron system
 	global_schedule string = '0 3'
 }

src/cron/cron.v

@@ -23,7 +23,7 @@ pub fn cron(conf Config) ? {
 	}
 
 	mut d := daemon.init_daemon(logger, conf.address, conf.api_key, conf.base_image, ce,
-		conf.max_concurrent_builds, conf.api_update_frequency) ?
+		conf.max_concurrent_builds, conf.api_update_frequency, conf.image_rebuild_frequency) ?
 
 	d.run() ?
 }

src/cron/daemon/build.v

@@ -3,6 +3,7 @@ module daemon
 import time
 import sync.stdatomic
 import rand
+import build
 
 const build_empty = 0
 
@@ -62,8 +63,9 @@ fn (mut d Daemon) start_build(sb ScheduledBuild) bool {
 
 // run_build actually starts the build process for a given repo.
 fn (mut d Daemon) run_build(build_index int, sb ScheduledBuild) ? {
-	d.linfo('build $sb.repo.url')
+	d.linfo('started build: ${sb.repo.url} ${sb.repo.branch}')
-	time.sleep(rand.int_in_range(1, 6) ? * time.second)
+
+	build.build_repo(d.address, d.api_key, d.builder_image, &sb.repo) ?
 
 	stdatomic.store_u64(&d.atomics[build_index], daemon.build_done)
 }

src/cron/daemon/daemon.v

@@ -6,6 +6,7 @@ import log
 import datatypes { MinHeap }
 import cron.expression { CronExpression, parse_expression }
 import math
+import build
 
 struct ScheduledBuild {
 pub:
@@ -23,12 +24,15 @@ mut:
 	address                 string
 	api_key                 string
 	base_image              string
+	builder_image           string
 	global_schedule         CronExpression
 	api_update_frequency    int
+	image_rebuild_frequency int
 	// Repos currently loaded from API.
 	repos_map map[string]git.GitRepo
 	// At what point to update the list of repositories.
 	api_update_timestamp  time.Time
+	image_build_timestamp time.Time
 	queue                 MinHeap<ScheduledBuild>
 	// Which builds are currently running
 	builds []ScheduledBuild
@@ -40,13 +44,14 @@ mut:
 
 // init_daemon initializes a new Daemon object. It renews the repositories &
 // populates the build queue for the first time.
-pub fn init_daemon(logger log.Log, address string, api_key string, base_image string, global_schedule CronExpression, max_concurrent_builds int, api_update_frequency int) ?Daemon {
+pub fn init_daemon(logger log.Log, address string, api_key string, base_image string, global_schedule CronExpression, max_concurrent_builds int, api_update_frequency int, image_rebuild_frequency int) ?Daemon {
 	mut d := Daemon{
 		address: address
 		api_key: api_key
 		base_image: base_image
 		global_schedule: global_schedule
 		api_update_frequency: api_update_frequency
+		image_rebuild_frequency: image_rebuild_frequency
 		atomics: []u64{len: max_concurrent_builds}
 		builds: []ScheduledBuild{len: max_concurrent_builds}
 		logger: logger
@@ -55,6 +60,7 @@ pub fn init_daemon(logger log.Log, address string, api_key string, base_image st
 	// Initialize the repos & queue
 	d.renew_repos() ?
 	d.renew_queue() ?
+	d.rebuild_base_image() ?
 
 	return d
 }
@@ -78,7 +84,15 @@ pub fn (mut d Daemon) run() ? {
 			}
 		}
 
-		// TODO rebuild builder image when needed
+		// TODO remove old builder images.
+		// This issue is less trivial than it sounds, because a build could
+		// still be running when the image has to be rebuilt. That would
+		// prevent the image from being removed. Therefore, we will need to
+		// keep track of a list or something & remove an image once we have
+		// made sure it isn't being used anymore.
+		if time.now() >= d.image_build_timestamp {
+			d.rebuild_base_image() ?
+		}
 
 		// Schedules new builds when possible
 		d.start_new_builds() ?
@@ -170,3 +184,10 @@ fn (mut d Daemon) renew_queue() ? {
 		d.schedule_build(id, repo) ?
 	}
 }
+
+fn (mut d Daemon) rebuild_base_image() ? {
+	d.linfo("Rebuilding builder image....")
+
+	d.builder_image = build.create_build_image(d.base_image) ?
+	d.image_build_timestamp = time.now().add_seconds(60 * d.image_rebuild_frequency)
+}