feat(agent): initial working version

jobs

src/agent/agent.v

@@ -20,6 +20,6 @@ pub fn agent(conf Config) ! {
 	logger.set_full_logpath(log_file)
 	logger.log_to_console_too()
 
-	mut d := agent.agent_init(logger, conf)
+	mut d := agent_init(logger, conf)
 	d.run()
 }

src/agent/cli.v

@@ -6,14 +6,16 @@ import conf as vconf
 struct Config {
 pub:
 	log_level string = 'WARN'
+	// Architecture that the agent represents
+	arch                  string
 	api_key               string
 	address               string
 	data_dir              string
 	max_concurrent_builds int = 1
 	polling_frequency     int = 30
 	// Architecture of agent
-	/* arch string */
+	// arch string
-	/* image_rebuild_frequency int    = 1440 */
+	image_rebuild_frequency int = 1440
 }
 
 // cmd returns the cli module that handles the cron daemon.

src/agent/daemon.v

@@ -4,6 +4,8 @@ import log
 import sync.stdatomic
 import build { BuildConfig }
 import client
+import time
+import os
 
 const (
 	build_empty   = 0
@@ -14,6 +16,8 @@ const (
 struct AgentDaemon {
 	logger shared log.Log
 	conf   Config
+mut:
+	images ImageManager
 	// Which builds are currently running; length is same as
 	// conf.max_concurrent_builds
 	builds []BuildConfig
@@ -28,6 +32,7 @@ fn agent_init(logger log.Log, conf Config) AgentDaemon {
 		logger: logger
 		client: client.new(conf.address, conf.api_key)
 		conf: conf
+		images: new_image_manager(conf.image_rebuild_frequency)
 		builds: []BuildConfig{len: conf.max_concurrent_builds}
 		atomics: []u64{len: conf.max_concurrent_builds}
 	}
@@ -36,18 +41,60 @@ fn agent_init(logger log.Log, conf Config) AgentDaemon {
 }
 
 pub fn (mut d AgentDaemon) run() {
+	// This is just so that the very first time the loop is ran, the jobs are
+	// always polled
+	mut last_poll_time := time.now().add_seconds(-d.conf.polling_frequency)
+
 	for {
 		free_builds := d.update_atomics()
 
-	  if  free_builds > 0  {
+		// All build slots are taken, so there's nothing to be done
-		
+		if free_builds == 0 {
+			time.sleep(1 * time.second)
+			continue
 		}
 
+		// Builds have finished, so old builder images might have freed up.
+		d.images.clean_old_images()
+
+		// Poll for new jobs
+		if time.now() >= last_poll_time.add_seconds(d.conf.polling_frequency) {
+			new_configs := d.client.poll_jobs(d.conf.arch, free_builds) or {
+				d.lerror('Failed to poll jobs: $err.msg()')
+
+				time.sleep(5 * time.second)
+				continue
+			}
+			last_poll_time = time.now()
+
+			// Schedule new jobs
+			for config in new_configs {
+				// TODO handle this better than to just skip the config
+				// Make sure a recent build base image is available for building the config
+				d.images.refresh_image(config.base_image) or {
+					d.lerror(err.msg())
+					continue
+				}
+				d.start_build(config)
+			}
+
+			time.sleep(1 * time.second)
+		}
+		// Builds are running, so check again after one second
+		else if free_builds < d.conf.max_concurrent_builds {
+			time.sleep(1 * time.second)
+		}
+		// The agent is not doing anything, so we just wait until the next poll
+		// time
+		else {
+			time_until_next_poll := time.now() - last_poll_time
+			time.sleep(time_until_next_poll)
+		}
 	}
 }
 
-// clean_finished_builds checks for each build whether it's completed, and sets
+// update_atomics checks for each build whether it's completed, and sets it to
-// it to free again if so. The return value is how many fields are now set to
+// free again if so. The return value is how many build slots are currently
 // free.
 fn (mut d AgentDaemon) update_atomics() int {
 	mut count := 0
@@ -63,3 +110,53 @@ fn (mut d AgentDaemon) update_atomics() int {
 
 	return count
 }
+
+// start_build starts a build for the given BuildConfig object.
+fn (mut d AgentDaemon) start_build(config BuildConfig) bool {
+	for i in 0 .. d.atomics.len {
+		if stdatomic.load_u64(&d.atomics[i]) == agent.build_empty {
+			stdatomic.store_u64(&d.atomics[i], agent.build_running)
+			d.builds[i] = config
+
+			go d.run_build(i, config)
+
+			return true
+		}
+	}
+
+	return false
+}
+
+// run_build actually starts the build process for a given target.
+fn (mut d AgentDaemon) run_build(build_index int, config BuildConfig) {
+	d.linfo('started build: $config.url -> $config.repo')
+
+	// 0 means success, 1 means failure
+	mut status := 0
+
+	new_config := BuildConfig{
+		...config
+		base_image: d.images.get(config.base_image)
+	}
+
+	res := build.build_config(d.client.address, d.client.api_key, new_config) or {
+		d.ldebug('build_config error: $err.msg()')
+		status = 1
+
+		build.BuildResult{}
+	}
+
+	if status == 0 {
+		d.linfo('finished build: $config.url -> $config.repo; uploading logs...')
+
+		build_arch := os.uname().machine
+		d.client.add_build_log(config.target_id, res.start_time, res.end_time, build_arch,
+			res.exit_code, res.logs) or {
+			d.lerror('Failed to upload logs for build: $config.url -> $config.repo')
+		}
+	} else {
+		d.linfo('an error occured during build: $config.url -> $config.repo')
+	}
+
+	stdatomic.store_u64(&d.atomics[build_index], agent.build_done)
+}

src/agent/images.v

@@ -0,0 +1,64 @@
+module agent
+
+import time
+import docker
+import build
+
+struct ImageManager {
+mut:
+	refresh_frequency int
+	images            map[string][]string  [required]
+	timestamps        map[string]time.Time [required]
+}
+
+fn new_image_manager(refresh_frequency int) ImageManager {
+	return ImageManager{
+		refresh_frequency: refresh_frequency
+		images: map[string][]string{}
+		timestamps: map[string]time.Time{}
+	}
+}
+
+pub fn (m &ImageManager) get(base_image string) string {
+	return m.images[base_image].last()
+}
+
+fn (mut m ImageManager) refresh_image(base_image string) ! {
+	// No need to refresh the image if the previous one is still new enough
+	if base_image in m.timestamps
+		&& m.timestamps[base_image].add_seconds(m.refresh_frequency) > time.now() {
+		return
+	}
+
+	// TODO use better image tags for built images
+	new_image := build.create_build_image(base_image) or {
+		return error('Failed to build builder image from base image $base_image')
+	}
+
+	m.images[base_image] << new_image
+	m.timestamps[base_image] = time.now()
+}
+
+// clean_old_images tries to remove any old but still present builder images.
+fn (mut m ImageManager) clean_old_images() {
+	mut dd := docker.new_conn() or { return }
+
+	defer {
+		dd.close() or {}
+	}
+
+	mut i := 0
+
+	for image in m.images.keys() {
+		i = 0
+
+		for i < m.images[image].len - 1 {
+			// For each builder image, we try to remove it by calling the Docker
+			// API. If the function returns an error or false, that means the image
+			// wasn't deleted. Therefore, we move the index over. If the function
+			// returns true, the array's length has decreased by one so we don't
+			// move the index.
+			dd.remove_image(m.images[image][i]) or { i += 1 }
+		}
+	}
+}

src/agent/log.v

@@ -0,0 +1,35 @@
+module agent
+
+import log
+
+// log reate a log message with the given level
+pub fn (mut d AgentDaemon) log(msg string, level log.Level) {
+	lock d.logger {
+		d.logger.send_output(msg, level)
+	}
+}
+
+// lfatal create a log message with the fatal level
+pub fn (mut d AgentDaemon) lfatal(msg string) {
+	d.log(msg, log.Level.fatal)
+}
+
+// lerror create a log message with the error level
+pub fn (mut d AgentDaemon) lerror(msg string) {
+	d.log(msg, log.Level.error)
+}
+
+// lwarn create a log message with the warn level
+pub fn (mut d AgentDaemon) lwarn(msg string) {
+	d.log(msg, log.Level.warn)
+}
+
+// linfo create a log message with the info level
+pub fn (mut d AgentDaemon) linfo(msg string) {
+	d.log(msg, log.Level.info)
+}
+
+// ldebug create a log message with the debug level
+pub fn (mut d AgentDaemon) ldebug(msg string) {
+	d.log(msg, log.Level.debug)
+}

src/build/build.v

@@ -18,7 +18,7 @@ const (
 
 pub struct BuildConfig {
 pub:
-	id int
+	target_id  int
 	kind       string
 	url        string
 	branch     string
@@ -103,10 +103,23 @@ pub:
 	logs       string
 }
 
+pub fn build_target(address string, api_key string, base_image_id string, target &Target) !BuildResult {
+	config := BuildConfig{
+		target_id: target.id
+		kind: target.kind
+		url: target.url
+		branch: target.branch
+		repo: target.repo
+		base_image: base_image_id
+	}
+
+	return build_config(address, api_key, config)
+}
+
 // build_target builds, packages & publishes a given Arch package based on the
 // provided target. The base image ID should be of an image previously created
 // by create_build_image. It returns the logs of the container.
-pub fn build_target(address string, api_key string, base_image_id string, target &Target) !BuildResult {
+pub fn build_config(address string, api_key string, config BuildConfig) !BuildResult {
 	mut dd := docker.new_conn()!
 
 	defer {
@@ -114,14 +127,14 @@ pub fn build_target(address string, api_key string, base_image_id string, target
 	}
 
 	build_arch := os.uname().machine
-	build_script := create_build_script(address, target, build_arch)
+	build_script := create_build_script(address, config, build_arch)
 
 	// We convert the build script into a base64 string, which then gets passed
 	// to the container as an env var
 	base64_script := base64.encode_str(build_script)
 
 	c := docker.NewContainer{
-		image: '$base_image_id'
+		image: '$config.base_image'
 		env: [
 			'BUILD_SCRIPT=$base64_script',
 			'API_KEY=$api_key',

src/build/queue.v

@@ -0,0 +1,168 @@
+module build
+
+import models { Target }
+import cron.expression { CronExpression, parse_expression }
+import time
+import datatypes { MinHeap }
+import util
+
+struct BuildJob {
+pub:
+	// Next timestamp from which point this job is allowed to be executed
+	timestamp time.Time
+	// Required for calculating next timestamp after having pop'ed a job
+	ce CronExpression
+	// Actual build config sent to the agent
+	config BuildConfig
+}
+
+// Allows BuildJob structs to be sorted according to their timestamp in
+// MinHeaps
+fn (r1 BuildJob) < (r2 BuildJob) bool {
+	return r1.timestamp < r2.timestamp
+}
+
+pub struct BuildJobQueue {
+	// Schedule to use for targets without explicitely defined cron expression
+	default_schedule CronExpression
+	// Base image to use for targets without defined base image
+	default_base_image string
+mut:
+	mutex shared util.Dummy
+	// For each architecture, a priority queue is tracked
+	queues map[string]MinHeap<BuildJob>
+	// Each queued build job is also stored in a map, with the keys being the
+	// target IDs. This is used when removing or editing targets.
+	// jobs map[int]BuildJob
+}
+
+pub fn new_job_queue(default_schedule CronExpression, default_base_image string) BuildJobQueue {
+	return BuildJobQueue{
+		default_schedule: default_schedule
+		default_base_image: default_base_image
+	}
+}
+
+// insert a new target's job into the queue for the given architecture. This
+// job will then be endlessly rescheduled after being pop'ed, unless removed
+// explicitely.
+pub fn (mut q BuildJobQueue) insert(target Target, arch string) ! {
+	lock q.mutex {
+		if arch !in q.queues {
+			q.queues[arch] = MinHeap<BuildJob>{}
+		}
+
+		ce := if target.schedule != '' {
+			parse_expression(target.schedule) or {
+				return error("Error while parsing cron expression '$target.schedule' (id $target.id): $err.msg()")
+			}
+		} else {
+			q.default_schedule
+		}
+
+		timestamp := ce.next_from_now()!
+
+		job := BuildJob{
+			timestamp: timestamp
+			ce: ce
+			config: BuildConfig{
+				target_id: target.id
+				kind: target.kind
+				url: target.url
+				branch: target.branch
+				repo: target.repo
+				// TODO make this configurable
+				base_image: q.default_base_image
+			}
+		}
+
+		q.queues[arch].insert(job)
+	}
+}
+
+// reschedule the given job by calculating the next timestamp and re-adding it
+// to its respective queue. This function is called by the pop functions
+// *after* having pop'ed the job.
+fn (mut q BuildJobQueue) reschedule(job BuildJob, arch string) ! {
+	new_timestamp := job.ce.next_from_now()!
+
+	new_job := BuildJob{
+		...job
+		timestamp: new_timestamp
+	}
+
+	q.queues[arch].insert(new_job)
+}
+
+// peek shows the first job for the given architecture that's ready to be
+// executed, if present.
+pub fn (q &BuildJobQueue) peek(arch string) ?BuildJob {
+	rlock q.mutex {
+		if arch !in q.queues {
+			return none
+		}
+
+		job := q.queues[arch].peek() or { return none }
+
+		if job.timestamp < time.now() {
+			return job
+		}
+	}
+
+	return none
+}
+
+// pop removes the first job for the given architecture that's ready to be
+// executed from the queue and returns it, if present.
+pub fn (mut q BuildJobQueue) pop(arch string) ?BuildJob {
+	lock q.mutex {
+		if arch !in q.queues {
+			return none
+		}
+
+		mut job := q.queues[arch].peek() or { return none }
+
+		if job.timestamp < time.now() {
+			job = q.queues[arch].pop()?
+
+			// TODO how do we handle this properly? Is it even possible for a
+			// cron expression to not return a next time if it's already been
+			// used before?
+			q.reschedule(job, arch) or {}
+
+			return job
+		}
+	}
+
+	return none
+}
+
+// pop_n tries to pop at most n available jobs for the given architecture.
+pub fn (mut q BuildJobQueue) pop_n(arch string, n int) []BuildJob {
+	lock q.mutex {
+		if arch !in q.queues {
+			return []
+		}
+
+		mut out := []BuildJob{}
+
+		for out.len < n {
+			mut job := q.queues[arch].peek() or { break }
+
+			if job.timestamp < time.now() {
+				job = q.queues[arch].pop() or { break }
+
+				// TODO idem
+				q.reschedule(job, arch) or {}
+
+				out << job
+			} else {
+				break
+			}
+		}
+
+		return out
+	}
+
+	return []
+}

src/build/shell.v

@@ -1,7 +1,5 @@
 module build
 
-import models { Target }
-
 // escape_shell_string escapes any characters that could be interpreted
 // incorrectly by a shell. The resulting value should be safe to use inside an
 // echo statement.
@@ -23,13 +21,13 @@ pub fn echo_commands(cmds []string) []string {
 }
 
 // create_build_script generates a shell script that builds a given Target.
-fn create_build_script(address string, target &Target, build_arch string) string {
+fn create_build_script(address string, config BuildConfig, build_arch string) string {
-	repo_url := '$address/$target.repo'
+	repo_url := '$address/$config.repo'
 
 	mut commands := [
 		// This will later be replaced by a proper setting for changing the
 		// mirrorlist
-		"echo -e '[$target.repo]\\nServer = $address/\$repo/\$arch\\nSigLevel = Optional' >> /etc/pacman.conf"
+		"echo -e '[$config.repo]\\nServer = $address/\$repo/\$arch\\nSigLevel = Optional' >> /etc/pacman.conf"
 		// We need to update the package list of the repo we just added above.
 		// This should however not pull in a lot of packages as long as the
 		// builder image is rebuilt frequently.
@@ -38,22 +36,22 @@ fn create_build_script(address string, target &Target, build_arch string) string
 		'su builder',
 	]
 
-	commands << match target.kind {
+	commands << match config.kind {
 		'git' {
-			if target.branch == '' {
+			if config.branch == '' {
 				[
-					"git clone --single-branch --depth 1 '$target.url' repo",
+					"git clone --single-branch --depth 1 '$config.url' repo",
 				]
 			} else {
 				[
-					"git clone --single-branch --depth 1 --branch $target.branch '$target.url' repo",
+					"git clone --single-branch --depth 1 --branch $config.branch '$config.url' repo",
 				]
 			}
 		}
 		'url' {
 			[
 				'mkdir repo',
-				"curl -o repo/PKGBUILD -L '$target.url'",
+				"curl -o repo/PKGBUILD -L '$config.url'",
 			]
 		}
 		else {

src/client/jobs.v

@@ -0,0 +1,12 @@
+module client
+
+import build { BuildConfig }
+
+pub fn (c &Client) poll_jobs(arch string, max int) ![]BuildConfig {
+	data := c.send_request<[]BuildConfig>(.get, '/api/v1/jobs/poll', {
+		'arch': arch
+		'max':  max.str()
+	})!
+
+	return data.data
+}

src/main.v

@@ -41,7 +41,7 @@ fn main() {
 			schedule.cmd(),
 			man.cmd(),
 			aur.cmd(),
-			agent.cmd()
+			agent.cmd(),
 		]
 	}
 	app.setup()

src/server/api_builds.v

@@ -0,0 +1,23 @@
+module server
+
+import web
+import web.response { new_data_response, new_response }
+// import os
+// import util
+// import models { BuildLog, BuildLogFilter }
+
+['/api/v1/jobs/poll'; auth; get]
+fn (mut app App) v1_poll_job_queue() web.Result {
+	arch := app.query['arch'] or {
+		return app.json(.bad_request, new_response('Missing arch query arg.'))
+	}
+
+	max_str := app.query['max'] or {
+		return app.json(.bad_request, new_response('Missing max query arg.'))
+	}
+	max := max_str.int()
+
+	mut out := app.job_queue.pop_n(arch, max).map(it.config)
+
+	return app.json(.ok, new_data_response(out))
+}

src/server/cli.v

@@ -10,7 +10,9 @@ pub:
 	data_dir        string
 	api_key         string
 	default_arch    string
+	global_schedule string = '0 3'
 	port            int    = 8000
+	base_image      string = 'archlinux:base-devel'
 }
 
 // cmd returns the cli submodule that handles starting the server

src/server/server.v

@@ -6,6 +6,8 @@ import log
 import repo
 import util
 import db
+import build { BuildJobQueue }
+import cron.expression
 
 const (
 	log_file_name = 'vieter.log'
@@ -20,9 +22,28 @@ pub:
 	conf Config [required; web_global]
 pub mut:
 	repo repo.RepoGroupManager [required; web_global]
+	// Keys are the various architectures for packages
+	job_queue BuildJobQueue [required; web_global]
 	db        db.VieterDb
 }
 
+fn (mut app App) init_job_queue() ! {
+	// Initialize build queues
+	mut targets := app.db.get_targets(limit: 25)
+	mut i := u64(0)
+
+	for targets.len > 0 {
+		for target in targets {
+			for arch in target.arch {
+				app.job_queue.insert(target, arch.value)!
+			}
+		}
+
+		i += 25
+		targets = app.db.get_targets(limit: 25, offset: i)
+	}
+}
+
 // server starts the web server & starts listening for requests
 pub fn server(conf Config) ! {
 	// Prevent using 'any' as the default arch
@@ -30,6 +51,10 @@ pub fn server(conf Config) ! {
 		util.exit_with_message(1, "'any' is not allowed as the value for default_arch.")
 	}
 
+	global_ce := expression.parse_expression(conf.global_schedule) or {
+		util.exit_with_message(1, 'Invalid global cron expression: $err.msg()')
+	}
+
 	// Configure logger
 	log_level := log.level_from_tag(conf.log_level) or {
 		util.exit_with_message(1, 'Invalid log level. The allowed values are FATAL, ERROR, WARN, INFO & DEBUG.')
@@ -71,11 +96,17 @@ pub fn server(conf Config) ! {
 		util.exit_with_message(1, 'Failed to initialize database: $err.msg()')
 	}
 
-	web.run(&App{
+	mut app := &App{
 		logger: logger
 		api_key: conf.api_key
 		conf: conf
 		repo: repo
 		db: db
-	}, conf.port)
+		job_queue: build.new_job_queue(global_ce, conf.base_image)
+	}
+	app.init_job_queue() or {
+		util.exit_with_message(1, 'Failed to inialize job queue: $err.msg()')
+	}
+
+	web.run(app, conf.port)
 }

vieter.toml

@@ -4,6 +4,7 @@ data_dir = "data"
 pkg_dir = "data/pkgs"
 log_level = "DEBUG"
 default_arch = "x86_64"
+arch = "x86_64"
 
 address = "http://localhost:8000"
 
@@ -11,4 +12,3 @@ global_schedule = '* *'
 api_update_frequency = 2
 image_rebuild_frequency = 1
 max_concurrent_builds = 3
-