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

src/cron/cli.v

@@ -5,13 +5,14 @@ import env
 
 struct Config {
 pub:
-	log_level             string = 'WARN'
-	log_file              string = 'vieter.log'
-	api_key               string
-	address               string
-	base_image            string = 'archlinux:base-devel'
-	max_concurrent_builds int    = 1
-	api_update_frequency  int    = 15
+	log_level               string = 'WARN'
+	log_file                string = 'vieter.log'
+	api_key                 string
+	address                 string
+	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')
-	time.sleep(rand.int_in_range(1, 6) ? * time.second)
+	d.linfo('started build: ${sb.repo.url} ${sb.repo.branch}')
+
+	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:
@@ -20,16 +21,19 @@ fn (r1 ScheduledBuild) < (r2 ScheduledBuild) bool {
 
 pub struct Daemon {
 mut:
-	address              string
-	api_key              string
-	base_image           string
-	global_schedule      CronExpression
-	api_update_frequency int
+	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
-	queue                MinHeap<ScheduledBuild>
+	api_update_timestamp  time.Time
+	image_build_timestamp time.Time
+	queue                 MinHeap<ScheduledBuild>
 	// Which builds are currently running
 	builds []ScheduledBuild
 	// Atomic variables used to detect when a build has finished; length is the
@@ -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)
+}