From 1d434db166918a19fee18c7d5e66c9c87e2ea9dd Mon Sep 17 00:00:00 2001
From: Jef Roosens <roosensjef@gmail.com>
Date: Mon, 21 Feb 2022 20:40:13 +0100
Subject: [PATCH 1/7] Wrote a proper env file system

---
 CHANGELOG.md |  3 ++
 Makefile     | 19 +++++++-----
 src/auth.v   |  2 +-
 src/build.v  | 13 ++++-----
 src/env.v    | 81 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 src/main.v   | 24 ++--------------
 src/routes.v |  4 +--
 src/server.v | 38 +++++++++++++-----------
 8 files changed, 128 insertions(+), 56 deletions(-)
 create mode 100644 src/env.v

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1166377..238fd00 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -15,6 +15,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
     * Packages are always rebuilt, even if they haven't changed
     * Hardcoded planning of builds
     * Builds are sequential
+* Better environment variable support
+    * Each env var can now be provided from a file by appending it with `_FILE`
+      & passing the path to the file as value
 
 ## Fixed
 
diff --git a/Makefile b/Makefile
index d69e48e..94b079b 100644
--- a/Makefile
+++ b/Makefile
@@ -34,16 +34,21 @@ c:
 # Run the server in the default 'data' directory
 .PHONY: run
 run: vieter
-	 API_KEY=test DOWNLOAD_DIR=data/downloads REPO_DIR=data/repo PKG_DIR=data/pkgs LOG_LEVEL=DEBUG ./vieter server
+	 VIETER_API_KEY=test \
+		VIETER_DOWNLOAD_DIR=data/downloads \
+		VIETER_REPO_DIR=data/repo \
+		VIETER_PKG_DIR=data/pkgs \
+		VIETER_LOG_LEVEL=DEBUG \
+		./vieter server
 
 .PHONY: run-prod
 run-prod: prod
-	API_KEY=test DOWNLOAD_DIR=data/downloads REPO_DIR=data/repo PKG_DIR=data/pkgs LOG_LEVEL=DEBUG ./pvieter
-
-# Same as run, but restart when the source code changes
-.PHONY: watch
-watch:
-	API_KEY=test DOWNLOAD_DIR=data/downloads REPO_DIR=data/repo PKG_DIR=data/pkgs LOG_LEVEL=DEBUG $(V) watch run vieter
+	VIETER_API_KEY=test \
+		VIETER_DOWNLOAD_DIR=data/downloads \
+		VIETER_REPO_DIR=data/repo \
+		VIETER_PKG_DIR=data/pkgs \
+		VIETER_LOG_LEVEL=DEBUG \
+	./pvieter server
 
 # =====OTHER=====
 .PHONY: lint
diff --git a/src/auth.v b/src/auth.v
index eab63c8..942bdda 100644
--- a/src/auth.v
+++ b/src/auth.v
@@ -7,5 +7,5 @@ fn (mut app App) is_authorized() bool {
 		return false
 	}
 
-	return x_header.trim_space() == app.api_key
+	return x_header.trim_space() == app.conf.api_key
 }
diff --git a/src/build.v b/src/build.v
index 00cf9ed..0acca8f 100644
--- a/src/build.v
+++ b/src/build.v
@@ -7,16 +7,15 @@ import time
 import os
 import json
 import git
+import env
 
 const container_build_dir = '/build'
 
-fn build(key string, repo_dir string) ? {
-	server_url := os.getenv_opt('VIETER_ADDRESS') or {
-		exit_with_message(1, 'No Vieter server address was provided.')
-	}
+fn build() ? {
+	conf := env.load<env.BuildConfig>() ?
 
 	// Read in the repos from a json file
-	filename := os.join_path_single(repo_dir, 'repos.json')
+	filename := os.join_path_single(conf.repo_dir, 'repos.json')
 	txt := os.read_file(filename) ?
 	repos := json.decode([]git.GitRepo, txt) ?
 
@@ -48,7 +47,7 @@ fn build(key string, repo_dir string) ? {
 		uuids << uuid
 
 		commands << "su builder -c 'git clone --single-branch --depth 1 --branch $repo.branch $repo.url /build/$uuid'"
-		commands << 'su builder -c \'cd /build/$uuid && makepkg -s --noconfirm --needed && for pkg in \$(ls -1 *.pkg*); do curl -XPOST -T "\${pkg}" -H "X-API-KEY: \$API_KEY" $server_url/publish; done\''
+		commands << 'su builder -c \'cd /build/$uuid && makepkg -s --noconfirm --needed && for pkg in \$(ls -1 *.pkg*); do curl -XPOST -T "\${pkg}" -H "X-API-KEY: \$API_KEY" $conf.address/publish; done\''
 	}
 
 	// We convert the list of commands into a base64 string, which then gets
@@ -57,7 +56,7 @@ fn build(key string, repo_dir string) ? {
 
 	c := docker.NewContainer{
 		image: 'archlinux:latest'
-		env: ['BUILD_SCRIPT=$cmds_str', 'API_KEY=$key']
+		env: ['BUILD_SCRIPT=$cmds_str', 'API_KEY=$conf.api_key']
 		entrypoint: ['/bin/sh', '-c']
 		cmd: ['echo \$BUILD_SCRIPT | base64 -d | /bin/sh -e']
 	}
diff --git a/src/env.v b/src/env.v
new file mode 100644
index 0000000..804d37c
--- /dev/null
+++ b/src/env.v
@@ -0,0 +1,81 @@
+module env
+
+import os
+
+// The prefix that every environment variable should have
+const prefix = 'VIETER_'
+
+// The suffix an environment variable in order for it to be loaded from a file
+// instead
+const file_suffix = '_FILE'
+
+pub struct ServerConfig {
+pub:
+	log_level string [default: WARN]
+	log_file string [default: 'vieter.log']
+	pkg_dir string
+	download_dir string
+	api_key string
+	repo_dir string
+}
+
+pub struct BuildConfig {
+pub:
+	api_key string
+	repo_dir string
+	address string
+}
+
+fn get_env_var(field_name string) ?string {
+	env_var_name := '${prefix}${field_name.to_upper()}'
+	env_file_name := '${prefix}${field_name.to_upper()}${file_suffix}'
+	env_var := os.getenv(env_var_name)
+	env_file := os.getenv(env_file_name)
+
+	// If both aren't set, we report them missing
+	if env_var == '' && env_file == '' {
+		return error('Either $env_var_name or $env_file_name is required.')
+	}
+
+	// If they're both set, we report a conflict
+	if env_var != '' && env_file != '' {
+		return error('Only one of $env_var_name or $env_file_name can be defined.')
+	}
+
+	// If it's the env var itself, we return it
+	if env_var != '' {
+		return env_var
+	}
+
+	// Otherwise, we process the file
+	return os.read_file(env_file) or {
+		error('Failed to read file defined in $env_file_name: ${err.msg}.')
+	}
+}
+
+// load attempts to create the given type from environment variables.
+pub fn load<T>() ?T {
+	res := T{}
+
+	$for field in T.fields {
+		res.$(field.name) = get_env_var(field.name) or {
+			// We use the default instead, if it's present
+			mut default := ''
+
+			for attr in field.attrs {
+				if attr.starts_with('default: ') {
+					default = attr[9..]
+					break
+				}
+			}
+
+			if default == '' {
+				return err
+			}
+
+			default
+		}
+	}
+
+	return res
+}
diff --git a/src/main.v b/src/main.v
index cc66b59..2472ac0 100644
--- a/src/main.v
+++ b/src/main.v
@@ -1,22 +1,7 @@
 module main
 
-import web
 import os
 import io
-import repo
-
-const port = 8000
-
-const buf_size = 1_000_000
-
-struct App {
-	web.Context
-pub:
-	api_key string [required; web_global]
-	dl_dir  string [required; web_global]
-pub mut:
-	repo repo.Repo [required; web_global]
-}
 
 [noreturn]
 fn exit_with_message(code int, msg string) {
@@ -51,18 +36,13 @@ fn reader_to_file(mut reader io.BufferedReader, length int, path string) ? {
 }
 
 fn main() {
-	key := os.getenv_opt('API_KEY') or { exit_with_message(1, 'No API key was provided.') }
-	repo_dir := os.getenv_opt('REPO_DIR') or {
-		exit_with_message(1, 'No repo directory was configured.')
-	}
-
 	if os.args.len == 1 {
 		exit_with_message(1, 'No action provided.')
 	}
 
 	match os.args[1] {
-		'server' { server(key, repo_dir) }
-		'build' { build(key, repo_dir) ? }
+		'server' { server() ? }
+		'build' { build() ? }
 		else { exit_with_message(1, 'Unknown action: ${os.args[1]}') }
 	}
 }
diff --git a/src/routes.v b/src/routes.v
index 8b7ddeb..b152a9f 100644
--- a/src/routes.v
+++ b/src/routes.v
@@ -58,10 +58,10 @@ fn (mut app App) put_package() web.Result {
 
 	if length := app.req.header.get(.content_length) {
 		// Generate a random filename for the temp file
-		pkg_path = os.join_path_single(app.dl_dir, rand.uuid_v4())
+		pkg_path = os.join_path_single(app.conf.download_dir, rand.uuid_v4())
 
 		for os.exists(pkg_path) {
-			pkg_path = os.join_path_single(app.dl_dir, rand.uuid_v4())
+			pkg_path = os.join_path_single(app.conf.download_dir, rand.uuid_v4())
 		}
 
 		app.ldebug("Uploading $length bytes (${pretty_bytes(length.int())}) to '$pkg_path'.")
diff --git a/src/server.v b/src/server.v
index e0f22ec..d5c5ab2 100644
--- a/src/server.v
+++ b/src/server.v
@@ -4,20 +4,33 @@ import web
 import os
 import log
 import repo
+import env
+
+const port = 8000
+
+const buf_size = 1_000_000
+
+struct App {
+	web.Context
+pub:
+	conf env.ServerConfig [required: web_global]
+pub mut:
+	repo repo.Repo [required; web_global]
+}
+
+fn server() ? {
+	conf := env.load<env.ServerConfig>() ?
 
-fn server(key string, repo_dir string) {
 	// Configure logger
-	log_level_str := os.getenv_opt('LOG_LEVEL') or { 'WARN' }
-	log_level := log.level_from_tag(log_level_str) or {
+	log_level := log.level_from_tag(conf.log_level) or {
 		exit_with_message(1, 'Invalid log level. The allowed values are FATAL, ERROR, WARN, INFO & DEBUG.')
 	}
-	log_file := os.getenv_opt('LOG_FILE') or { 'vieter.log' }
 
 	mut logger := log.Log{
 		level: log_level
 	}
 
-	logger.set_full_logpath(log_file)
+	logger.set_full_logpath(conf.log_file)
 	logger.log_to_console_too()
 
 	defer {
@@ -26,26 +39,17 @@ fn server(key string, repo_dir string) {
 		logger.close()
 	}
 
-	// Configure web server
-	pkg_dir := os.getenv_opt('PKG_DIR') or {
-		exit_with_message(1, 'No package directory was configured.')
-	}
-	dl_dir := os.getenv_opt('DOWNLOAD_DIR') or {
-		exit_with_message(1, 'No download directory was configured.')
-	}
-
 	// This also creates the directories if needed
-	repo := repo.new(repo_dir, pkg_dir) or {
+	repo := repo.new(conf.repo_dir, conf.pkg_dir) or {
 		logger.error(err.msg)
 		exit(1)
 	}
 
-	os.mkdir_all(dl_dir) or { exit_with_message(1, 'Failed to create download directory.') }
+	os.mkdir_all(conf.download_dir) or { exit_with_message(1, 'Failed to create download directory.') }
 
 	web.run(&App{
 		logger: logger
-		api_key: key
-		dl_dir: dl_dir
+		conf: conf
 		repo: repo
 	}, port)
 }

From 92ad0c51eb5ea0ef75a90bcf46d6d00b94e44007 Mon Sep 17 00:00:00 2001
From: Jef Roosens <roosensjef@gmail.com>
Date: Mon, 21 Feb 2022 20:51:41 +0100
Subject: [PATCH 2/7] Split off server into own module

---
 src/env.v                 | 19 +++++++++---------
 src/main.v                | 41 +++++----------------------------------
 src/{ => server}/auth.v   |  2 +-
 src/{ => server}/routes.v |  7 ++++---
 src/{ => server}/server.v | 15 +++++++-------
 src/util.v                | 35 +++++++++++++++++++++++++++++++++
 6 files changed, 62 insertions(+), 57 deletions(-)
 rename src/{ => server}/auth.v (94%)
 rename src/{ => server}/routes.v (95%)
 rename src/{ => server}/server.v (72%)

diff --git a/src/env.v b/src/env.v
index 804d37c..2cbcf63 100644
--- a/src/env.v
+++ b/src/env.v
@@ -11,24 +11,24 @@ const file_suffix = '_FILE'
 
 pub struct ServerConfig {
 pub:
-	log_level string [default: WARN]
-	log_file string [default: 'vieter.log']
-	pkg_dir string
+	log_level    string [default: WARN]
+	log_file     string [default: 'vieter.log']
+	pkg_dir      string
 	download_dir string
-	api_key string
-	repo_dir string
+	api_key      string
+	repo_dir     string
 }
 
 pub struct BuildConfig {
 pub:
-	api_key string
+	api_key  string
 	repo_dir string
-	address string
+	address  string
 }
 
 fn get_env_var(field_name string) ?string {
-	env_var_name := '${prefix}${field_name.to_upper()}'
-	env_file_name := '${prefix}${field_name.to_upper()}${file_suffix}'
+	env_var_name := '$env.prefix$field_name.to_upper()'
+	env_file_name := '$env.prefix$field_name.to_upper()$env.file_suffix'
 	env_var := os.getenv(env_var_name)
 	env_file := os.getenv(env_file_name)
 
@@ -76,6 +76,5 @@ pub fn load<T>() ?T {
 			default
 		}
 	}
-
 	return res
 }
diff --git a/src/main.v b/src/main.v
index 2472ac0..156f0a3 100644
--- a/src/main.v
+++ b/src/main.v
@@ -1,48 +1,17 @@
 module main
 
 import os
-import io
-
-[noreturn]
-fn exit_with_message(code int, msg string) {
-	eprintln(msg)
-	exit(code)
-}
-
-fn reader_to_file(mut reader io.BufferedReader, length int, path string) ? {
-	mut file := os.create(path) ?
-	defer {
-		file.close()
-	}
-
-	mut buf := []byte{len: buf_size}
-	mut bytes_left := length
-
-	// Repeat as long as the stream still has data
-	for bytes_left > 0 {
-		// TODO check if just breaking here is safe
-		bytes_read := reader.read(mut buf) or { break }
-		bytes_left -= bytes_read
-
-		mut to_write := bytes_read
-
-		for to_write > 0 {
-			// TODO don't just loop infinitely here
-			bytes_written := file.write(buf[bytes_read - to_write..bytes_read]) or { continue }
-
-			to_write = to_write - bytes_written
-		}
-	}
-}
+import server
+import util
 
 fn main() {
 	if os.args.len == 1 {
-		exit_with_message(1, 'No action provided.')
+		util.exit_with_message(1, 'No action provided.')
 	}
 
 	match os.args[1] {
-		'server' { server() ? }
+		'server' { server.server() ? }
 		'build' { build() ? }
-		else { exit_with_message(1, 'Unknown action: ${os.args[1]}') }
+		else { util.exit_with_message(1, 'Unknown action: ${os.args[1]}') }
 	}
 }
diff --git a/src/auth.v b/src/server/auth.v
similarity index 94%
rename from src/auth.v
rename to src/server/auth.v
index 942bdda..8bc9d55 100644
--- a/src/auth.v
+++ b/src/server/auth.v
@@ -1,4 +1,4 @@
-module main
+module server
 
 import net.http
 
diff --git a/src/routes.v b/src/server/routes.v
similarity index 95%
rename from src/routes.v
rename to src/server/routes.v
index b152a9f..872894e 100644
--- a/src/routes.v
+++ b/src/server/routes.v
@@ -1,10 +1,11 @@
-module main
+module server
 
 import web
 import os
 import repo
 import time
 import rand
+import util
 
 const prefixes = ['B', 'KB', 'MB', 'GB']
 
@@ -18,7 +19,7 @@ fn pretty_bytes(bytes int) string {
 		n /= 1024
 	}
 
-	return '${n:.2}${prefixes[i]}'
+	return '${n:.2}${server.prefixes[i]}'
 }
 
 fn is_pkg_name(s string) bool {
@@ -69,7 +70,7 @@ fn (mut app App) put_package() web.Result {
 		// This is used to time how long it takes to upload a file
 		mut sw := time.new_stopwatch(time.StopWatchOptions{ auto_start: true })
 
-		reader_to_file(mut app.reader, length.int(), pkg_path) or {
+		util.reader_to_file(mut app.reader, length.int(), pkg_path) or {
 			app.lwarn("Failed to upload '$pkg_path'")
 
 			return app.text('Failed to upload file.')
diff --git a/src/server.v b/src/server/server.v
similarity index 72%
rename from src/server.v
rename to src/server/server.v
index d5c5ab2..3b16c63 100644
--- a/src/server.v
+++ b/src/server/server.v
@@ -1,15 +1,14 @@
-module main
+module server
 
 import web
 import os
 import log
 import repo
 import env
+import util
 
 const port = 8000
 
-const buf_size = 1_000_000
-
 struct App {
 	web.Context
 pub:
@@ -18,12 +17,12 @@ pub mut:
 	repo repo.Repo [required; web_global]
 }
 
-fn server() ? {
+pub fn server() ? {
 	conf := env.load<env.ServerConfig>() ?
 
 	// Configure logger
 	log_level := log.level_from_tag(conf.log_level) or {
-		exit_with_message(1, 'Invalid log level. The allowed values are FATAL, ERROR, WARN, INFO & DEBUG.')
+		util.exit_with_message(1, 'Invalid log level. The allowed values are FATAL, ERROR, WARN, INFO & DEBUG.')
 	}
 
 	mut logger := log.Log{
@@ -45,11 +44,13 @@ fn server() ? {
 		exit(1)
 	}
 
-	os.mkdir_all(conf.download_dir) or { exit_with_message(1, 'Failed to create download directory.') }
+	os.mkdir_all(conf.download_dir) or {
+		util.exit_with_message(1, 'Failed to create download directory.')
+	}
 
 	web.run(&App{
 		logger: logger
 		conf: conf
 		repo: repo
-	}, port)
+	}, server.port)
 }
diff --git a/src/util.v b/src/util.v
index f81a256..d0fa984 100644
--- a/src/util.v
+++ b/src/util.v
@@ -1,9 +1,44 @@
 module util
 
 import os
+import io
 import crypto.md5
 import crypto.sha256
 
+const reader_buf_size = 1_000_000
+
+[noreturn]
+pub fn exit_with_message(code int, msg string) {
+	eprintln(msg)
+	exit(code)
+}
+
+pub fn reader_to_file(mut reader io.BufferedReader, length int, path string) ? {
+	mut file := os.create(path) ?
+	defer {
+		file.close()
+	}
+
+	mut buf := []byte{len: util.reader_buf_size}
+	mut bytes_left := length
+
+	// Repeat as long as the stream still has data
+	for bytes_left > 0 {
+		// TODO check if just breaking here is safe
+		bytes_read := reader.read(mut buf) or { break }
+		bytes_left -= bytes_read
+
+		mut to_write := bytes_read
+
+		for to_write > 0 {
+			// TODO don't just loop infinitely here
+			bytes_written := file.write(buf[bytes_read - to_write..bytes_read]) or { continue }
+
+			to_write = to_write - bytes_written
+		}
+	}
+}
+
 // hash_file returns the md5 & sha256 hash of a given file
 // TODO actually implement sha256
 pub fn hash_file(path &string) ?(string, string) {

From e13252d36826004f298a96c2ed4bb8e9df4ea61c Mon Sep 17 00:00:00 2001
From: Jef Roosens <roosensjef@gmail.com>
Date: Mon, 21 Feb 2022 22:22:36 +0100
Subject: [PATCH 3/7] Initial part of repos API (SEGFAULTS) [CI SKIP]

---
 .gitignore          |   3 ++
 Makefile            |  13 +++++-
 src/build.v         |   4 +-
 src/env.v           |   6 ++-
 src/git.v           |   7 ----
 src/repo/repo.v     |   9 +---
 src/server/git.v    | 100 ++++++++++++++++++++++++++++++++++++++++++++
 src/server/routes.v |  21 +---------
 src/server/server.v |   4 +-
 src/util.v          |  22 ++++++++++
 10 files changed, 150 insertions(+), 39 deletions(-)
 delete mode 100644 src/git.v
 create mode 100644 src/server/git.v

diff --git a/.gitignore b/.gitignore
index ca2e2f8..3a6b11b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -18,3 +18,6 @@ test/
 
 # V compiler directory
 v/
+
+# gdb log file
+gdb.txt
diff --git a/Makefile b/Makefile
index 94b079b..b1b91f2 100644
--- a/Makefile
+++ b/Makefile
@@ -16,7 +16,17 @@ vieter: $(SOURCES)
 .PHONY: debug
 debug: dvieter
 dvieter: $(SOURCES)
-	$(V) -keepc -cg -cc gcc -o dvieter $(SRC_DIR)
+	$(V_PATH) -showcc -keepc -cg -o dvieter $(SRC_DIR)
+
+.PHONY: gdb
+gdb: dvieter
+	 VIETER_API_KEY=test \
+		VIETER_DOWNLOAD_DIR=data/downloads \
+		VIETER_REPO_DIR=data/repo \
+		VIETER_PKG_DIR=data/pkgs \
+		VIETER_LOG_LEVEL=DEBUG \
+		VIETER_REPOS_FILE=data/repos.json \
+		gdb --args ./dvieter
 
 # Optimised production build
 .PHONY: prod
@@ -39,6 +49,7 @@ run: vieter
 		VIETER_REPO_DIR=data/repo \
 		VIETER_PKG_DIR=data/pkgs \
 		VIETER_LOG_LEVEL=DEBUG \
+		VIETER_REPOS_FILE=data/repos.json \
 		./vieter server
 
 .PHONY: run-prod
diff --git a/src/build.v b/src/build.v
index 0acca8f..8d6af14 100644
--- a/src/build.v
+++ b/src/build.v
@@ -6,7 +6,7 @@ import rand
 import time
 import os
 import json
-import git
+import server
 import env
 
 const container_build_dir = '/build'
@@ -17,7 +17,7 @@ fn build() ? {
 	// Read in the repos from a json file
 	filename := os.join_path_single(conf.repo_dir, 'repos.json')
 	txt := os.read_file(filename) ?
-	repos := json.decode([]git.GitRepo, txt) ?
+	repos := json.decode([]server.GitRepo, txt) ?
 
 	mut commands := [
 		// Update repos & install required packages
diff --git a/src/env.v b/src/env.v
index 2cbcf63..1e601bd 100644
--- a/src/env.v
+++ b/src/env.v
@@ -17,6 +17,7 @@ pub:
 	download_dir string
 	api_key      string
 	repo_dir     string
+	repos_file string
 }
 
 pub struct BuildConfig {
@@ -42,7 +43,10 @@ fn get_env_var(field_name string) ?string {
 		return error('Only one of $env_var_name or $env_file_name can be defined.')
 	}
 
-	// If it's the env var itself, we return it
+	// If it's the env var itself, we return it.
+	// I'm pretty sure this also prevents variable ending in _FILE (e.g.
+	// VIETER_LOG_FILE) from being mistakingely read as an _FILE suffixed env
+	// var.
 	if env_var != '' {
 		return env_var
 	}
diff --git a/src/git.v b/src/git.v
deleted file mode 100644
index 76d80d7..0000000
--- a/src/git.v
+++ /dev/null
@@ -1,7 +0,0 @@
-module git
-
-pub struct GitRepo {
-pub:
-	url    string [required]
-	branch string [required]
-}
diff --git a/src/repo/repo.v b/src/repo/repo.v
index 1bf2d0c..f1419ac 100644
--- a/src/repo/repo.v
+++ b/src/repo/repo.v
@@ -2,17 +2,12 @@ module repo
 
 import os
 import package
-
-// Dummy struct to work around the fact that you can only share structs, maps &
-// arrays
-pub struct Dummy {
-	x int
-}
+import util
 
 // This struct manages a single repository.
 pub struct Repo {
 mut:
-	mutex shared Dummy
+	mutex shared util.Dummy
 pub:
 	// Where to store repository files
 	repo_dir string [required]
diff --git a/src/server/git.v b/src/server/git.v
new file mode 100644
index 0000000..6a1d929
--- /dev/null
+++ b/src/server/git.v
@@ -0,0 +1,100 @@
+module server
+
+import web
+import os
+import json
+
+const repos_file = 'repos.json'
+
+pub struct GitRepo {
+pub:
+	url    string [required]
+	branch string [required]
+}
+
+fn read_repos(path string) ?[]GitRepo {
+	if !os.exists(path) {
+		mut f := os.create(path) ?
+
+		defer {
+			f.close()
+		}
+
+		f.write_string('{}') ?
+
+		return []
+	}
+
+	content := os.read_file(path) ?
+	return json.decode([]GitRepo, content)
+}
+
+fn write_repos(path string, repos []GitRepo) ? {
+	mut f := os.create(path) ?
+
+	defer {
+		f.close()
+	}
+
+	dump(repos)
+	value := json.encode(repos)
+	f.write_string(value) ?
+}
+
+['/api/repos'; get]
+pub fn (mut app App) get_repos() web.Result {
+	if !app.is_authorized() {
+		return app.text('Unauthorized.')
+	}
+
+	repos := rlock app.git_mutex {
+		read_repos(app.conf.repos_file) or {
+			app.lerror('Failed to read repos file.')
+
+			return app.server_error(500)
+		}
+	}
+
+	return app.json(repos)
+}
+
+['/api/repos'; post]
+pub fn (mut app App) post_repo() web.Result {
+	if !app.is_authorized() {
+		return app.text('Unauthorized.')
+	}
+
+	if !('url' in app.query && 'branch' in app.query) {
+		return app.server_error(400)
+	}
+
+	new_repo := GitRepo{
+		url: app.query['url']
+		branch: app.query['branch']
+	}
+
+	mut repos := rlock app.git_mutex {
+		read_repos(app.conf.repos_file) or {
+			app.lerror('Failed to read repos file.')
+
+			return app.server_error(500)
+		}
+	}
+
+	// We need to check for duplicates
+	for r in repos {
+		if r == new_repo {
+			return app.text('Duplicate repository.')
+		}
+	}
+
+	repos << new_repo
+
+	lock app.git_mutex {
+		write_repos(app.conf.repos_file, repos) or {
+			return app.server_error(500)
+		}
+	}
+
+	return app.ok('Repo added successfully.')
+}
diff --git a/src/server/routes.v b/src/server/routes.v
index 872894e..7a0ee38 100644
--- a/src/server/routes.v
+++ b/src/server/routes.v
@@ -7,25 +7,6 @@ import time
 import rand
 import util
 
-const prefixes = ['B', 'KB', 'MB', 'GB']
-
-// pretty_bytes converts a byte count to human-readable version
-fn pretty_bytes(bytes int) string {
-	mut i := 0
-	mut n := f32(bytes)
-
-	for n >= 1024 {
-		i++
-		n /= 1024
-	}
-
-	return '${n:.2}${server.prefixes[i]}'
-}
-
-fn is_pkg_name(s string) bool {
-	return s.contains('.pkg')
-}
-
 // healthcheck just returns a string, but can be used to quickly check if the
 // server is still responsive.
 ['/health'; get]
@@ -65,7 +46,7 @@ fn (mut app App) put_package() web.Result {
 			pkg_path = os.join_path_single(app.conf.download_dir, rand.uuid_v4())
 		}
 
-		app.ldebug("Uploading $length bytes (${pretty_bytes(length.int())}) to '$pkg_path'.")
+		app.ldebug("Uploading $length bytes (${util.pretty_bytes(length.int())}) to '$pkg_path'.")
 
 		// This is used to time how long it takes to upload a file
 		mut sw := time.new_stopwatch(time.StopWatchOptions{ auto_start: true })
diff --git a/src/server/server.v b/src/server/server.v
index 3b16c63..ebb9f3b 100644
--- a/src/server/server.v
+++ b/src/server/server.v
@@ -12,9 +12,11 @@ const port = 8000
 struct App {
 	web.Context
 pub:
-	conf env.ServerConfig [required: web_global]
+	conf env.ServerConfig [required; web_global]
 pub mut:
 	repo repo.Repo [required; web_global]
+	// This is used to claim the file lock on the repos file
+	git_mutex shared util.Dummy
 }
 
 pub fn server() ? {
diff --git a/src/util.v b/src/util.v
index d0fa984..65d5294 100644
--- a/src/util.v
+++ b/src/util.v
@@ -7,6 +7,14 @@ import crypto.sha256
 
 const reader_buf_size = 1_000_000
 
+const prefixes = ['B', 'KB', 'MB', 'GB']
+
+// Dummy struct to work around the fact that you can only share structs, maps &
+// arrays
+pub struct Dummy {
+	x int
+}
+
 [noreturn]
 pub fn exit_with_message(code int, msg string) {
 	eprintln(msg)
@@ -67,3 +75,17 @@ pub fn hash_file(path &string) ?(string, string) {
 
 	return md5sum.checksum().hex(), sha256sum.checksum().hex()
 }
+
+// pretty_bytes converts a byte count to human-readable version
+pub fn pretty_bytes(bytes int) string {
+	mut i := 0
+	mut n := f32(bytes)
+
+	for n >= 1024 {
+		i++
+		n /= 1024
+	}
+
+	return '${n:.2}${util.prefixes[i]}'
+}
+

From 398758a72790f8ebdf9e1b5276e8a0ed8d5b57a7 Mon Sep 17 00:00:00 2001
From: Jef Roosens <roosensjef@gmail.com>
Date: Mon, 21 Feb 2022 22:32:54 +0100
Subject: [PATCH 4/7] Fixed segfault

All together now: thank you spytheman
---
 src/env.v        |  2 +-
 src/server/git.v | 10 ++++------
 src/util.v       |  1 -
 3 files changed, 5 insertions(+), 8 deletions(-)

diff --git a/src/env.v b/src/env.v
index 1e601bd..26919f8 100644
--- a/src/env.v
+++ b/src/env.v
@@ -17,7 +17,7 @@ pub:
 	download_dir string
 	api_key      string
 	repo_dir     string
-	repos_file string
+	repos_file   string
 }
 
 pub struct BuildConfig {
diff --git a/src/server/git.v b/src/server/git.v
index 6a1d929..8c569e6 100644
--- a/src/server/git.v
+++ b/src/server/git.v
@@ -20,13 +20,14 @@ fn read_repos(path string) ?[]GitRepo {
 			f.close()
 		}
 
-		f.write_string('{}') ?
+		f.write_string('[]') ?
 
 		return []
 	}
 
 	content := os.read_file(path) ?
-	return json.decode([]GitRepo, content)
+	res := json.decode([]GitRepo, content) ?
+	return res
 }
 
 fn write_repos(path string, repos []GitRepo) ? {
@@ -36,7 +37,6 @@ fn write_repos(path string, repos []GitRepo) ? {
 		f.close()
 	}
 
-	dump(repos)
 	value := json.encode(repos)
 	f.write_string(value) ?
 }
@@ -91,9 +91,7 @@ pub fn (mut app App) post_repo() web.Result {
 	repos << new_repo
 
 	lock app.git_mutex {
-		write_repos(app.conf.repos_file, repos) or {
-			return app.server_error(500)
-		}
+		write_repos(app.conf.repos_file, repos) or { return app.server_error(500) }
 	}
 
 	return app.ok('Repo added successfully.')
diff --git a/src/util.v b/src/util.v
index 65d5294..24d33fc 100644
--- a/src/util.v
+++ b/src/util.v
@@ -88,4 +88,3 @@ pub fn pretty_bytes(bytes int) string {
 
 	return '${n:.2}${util.prefixes[i]}'
 }
-

From fe98112f796d39bb14175386f6e0a0b29e94500b Mon Sep 17 00:00:00 2001
From: Jef Roosens <roosensjef@gmail.com>
Date: Mon, 21 Feb 2022 22:40:59 +0100
Subject: [PATCH 5/7] Added repos delete route

---
 src/server/git.v | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/src/server/git.v b/src/server/git.v
index 8c569e6..d506c7e 100644
--- a/src/server/git.v
+++ b/src/server/git.v
@@ -96,3 +96,34 @@ pub fn (mut app App) post_repo() web.Result {
 
 	return app.ok('Repo added successfully.')
 }
+
+['/api/repos'; delete]
+pub fn (mut app App) delete_repo() web.Result {
+	if !app.is_authorized() {
+		return app.text('Unauthorized.')
+	}
+
+	if !('url' in app.query && 'branch' in app.query) {
+		return app.server_error(400)
+	}
+
+	repo_to_remove := GitRepo{
+		url: app.query['url']
+		branch: app.query['branch']
+	}
+
+	mut repos := rlock app.git_mutex {
+		read_repos(app.conf.repos_file) or {
+			app.lerror('Failed to read repos file.')
+
+			return app.server_error(500)
+		}
+	}
+	filtered := repos.filter(it != repo_to_remove)
+
+	lock app.git_mutex {
+		write_repos(app.conf.repos_file, filtered) or { return app.server_error(500) }
+	}
+
+	return app.ok('Repo removed successfully.')
+}

From 6194a3f4086bf97009d6c83c5eb687032bb9e924 Mon Sep 17 00:00:00 2001
From: Jef Roosens <roosensjef@gmail.com>
Date: Mon, 21 Feb 2022 22:58:05 +0100
Subject: [PATCH 6/7] Builder now gets list of repos from server

---
 CHANGELOG.md |  1 +
 src/build.v  | 11 +++++++----
 src/env.v    |  1 -
 3 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 238fd00..edae68b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -18,6 +18,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 * Better environment variable support
     * Each env var can now be provided from a file by appending it with `_FILE`
       & passing the path to the file as value
+* API for managing Git repositories to build
 
 ## Fixed
 
diff --git a/src/build.v b/src/build.v
index 8d6af14..ab72a59 100644
--- a/src/build.v
+++ b/src/build.v
@@ -8,16 +8,19 @@ import os
 import json
 import server
 import env
+import net.http
 
 const container_build_dir = '/build'
 
 fn build() ? {
 	conf := env.load<env.BuildConfig>() ?
 
-	// Read in the repos from a json file
-	filename := os.join_path_single(conf.repo_dir, 'repos.json')
-	txt := os.read_file(filename) ?
-	repos := json.decode([]server.GitRepo, txt) ?
+	// We get the repos list from the Vieter instance
+	mut req := http.new_request(http.Method.get, '${conf.address}/api/repos', '') ?
+	req.add_custom_header('X-Api-Key', conf.api_key) ?
+
+	res := req.do() ?
+	repos := json.decode([]server.GitRepo, res.text) ?
 
 	mut commands := [
 		// Update repos & install required packages
diff --git a/src/env.v b/src/env.v
index 26919f8..8b92d8d 100644
--- a/src/env.v
+++ b/src/env.v
@@ -23,7 +23,6 @@ pub:
 pub struct BuildConfig {
 pub:
 	api_key  string
-	repo_dir string
 	address  string
 }
 

From 27f59c6664e7b4fbb15e3b49735c55417f9f7605 Mon Sep 17 00:00:00 2001
From: Jef Roosens <roosensjef@gmail.com>
Date: Tue, 22 Feb 2022 08:14:20 +0100
Subject: [PATCH 7/7] Updated CI Dockerfile; fixed formatting & vet

---
 Dockerfile.ci       | 7 ++++---
 Makefile            | 3 +++
 src/build.v         | 3 +--
 src/env.v           | 9 ++++++---
 src/server/git.v    | 6 +++---
 src/server/server.v | 1 +
 src/util.v          | 3 +++
 7 files changed, 21 insertions(+), 11 deletions(-)

diff --git a/Dockerfile.ci b/Dockerfile.ci
index e0dd5da..a062d95 100644
--- a/Dockerfile.ci
+++ b/Dockerfile.ci
@@ -24,9 +24,10 @@ RUN curl --fail \
 FROM busybox:1.35.0
 
 ENV PATH=/bin \
-    REPO_DIR=/data/repo \
-    PKG_DIR=/data/pkgs \
-    DOWNLOAD_DIR=/data/downloads
+    VIETER_REPO_DIR=/data/repo \
+    VIETER_PKG_DIR=/data/pkgs \
+    VIETER_DOWNLOAD_DIR=/data/downloads \
+    VIETER_REPOS_FILE=/data/repos.json
 
 COPY --from=builder /app/dumb-init /app/vieter /bin/
 
diff --git a/Makefile b/Makefile
index b1b91f2..062a47f 100644
--- a/Makefile
+++ b/Makefile
@@ -13,11 +13,14 @@ vieter: $(SOURCES)
 	$(V) -g -o vieter $(SRC_DIR)
 
 # Debug build using gcc
+# The debug build can't use the boehm garbage collector, as that is
+# multi-threaded and causes issues when running vieter inside gdb.
 .PHONY: debug
 debug: dvieter
 dvieter: $(SOURCES)
 	$(V_PATH) -showcc -keepc -cg -o dvieter $(SRC_DIR)
 
+# Run the debug build inside gdb
 .PHONY: gdb
 gdb: dvieter
 	 VIETER_API_KEY=test \
diff --git a/src/build.v b/src/build.v
index ab72a59..fc1fe6f 100644
--- a/src/build.v
+++ b/src/build.v
@@ -4,7 +4,6 @@ import docker
 import encoding.base64
 import rand
 import time
-import os
 import json
 import server
 import env
@@ -16,7 +15,7 @@ fn build() ? {
 	conf := env.load<env.BuildConfig>() ?
 
 	// We get the repos list from the Vieter instance
-	mut req := http.new_request(http.Method.get, '${conf.address}/api/repos', '') ?
+	mut req := http.new_request(http.Method.get, '$conf.address/api/repos', '') ?
 	req.add_custom_header('X-Api-Key', conf.api_key) ?
 
 	res := req.do() ?
diff --git a/src/env.v b/src/env.v
index 8b92d8d..bd544cf 100644
--- a/src/env.v
+++ b/src/env.v
@@ -22,8 +22,8 @@ pub:
 
 pub struct BuildConfig {
 pub:
-	api_key  string
-	address  string
+	api_key string
+	address string
 }
 
 fn get_env_var(field_name string) ?string {
@@ -56,7 +56,10 @@ fn get_env_var(field_name string) ?string {
 	}
 }
 
-// load attempts to create the given type from environment variables.
+// load<T> attempts to create the given type from environment variables. For
+// each field, the corresponding env var is its name in uppercase prepended
+// with the hardcoded prefix. If this one isn't present, it looks for the env
+// var with the file_suffix suffix.
 pub fn load<T>() ?T {
 	res := T{}
 
diff --git a/src/server/git.v b/src/server/git.v
index d506c7e..0147d87 100644
--- a/src/server/git.v
+++ b/src/server/git.v
@@ -42,7 +42,7 @@ fn write_repos(path string, repos []GitRepo) ? {
 }
 
 ['/api/repos'; get]
-pub fn (mut app App) get_repos() web.Result {
+fn (mut app App) get_repos() web.Result {
 	if !app.is_authorized() {
 		return app.text('Unauthorized.')
 	}
@@ -59,7 +59,7 @@ pub fn (mut app App) get_repos() web.Result {
 }
 
 ['/api/repos'; post]
-pub fn (mut app App) post_repo() web.Result {
+fn (mut app App) post_repo() web.Result {
 	if !app.is_authorized() {
 		return app.text('Unauthorized.')
 	}
@@ -98,7 +98,7 @@ pub fn (mut app App) post_repo() web.Result {
 }
 
 ['/api/repos'; delete]
-pub fn (mut app App) delete_repo() web.Result {
+fn (mut app App) delete_repo() web.Result {
 	if !app.is_authorized() {
 		return app.text('Unauthorized.')
 	}
diff --git a/src/server/server.v b/src/server/server.v
index ebb9f3b..4b31b99 100644
--- a/src/server/server.v
+++ b/src/server/server.v
@@ -19,6 +19,7 @@ pub mut:
 	git_mutex shared util.Dummy
 }
 
+// server starts the web server & starts listening for requests
 pub fn server() ? {
 	conf := env.load<env.ServerConfig>() ?
 
diff --git a/src/util.v b/src/util.v
index 24d33fc..49c9d22 100644
--- a/src/util.v
+++ b/src/util.v
@@ -15,12 +15,15 @@ pub struct Dummy {
 	x int
 }
 
+// exit_with_message exits the program with a given status code after having
+// first printed a specific message to STDERR
 [noreturn]
 pub fn exit_with_message(code int, msg string) {
 	eprintln(msg)
 	exit(code)
 }
 
+// reader_to_file writes the contents of a BufferedReader to a file
 pub fn reader_to_file(mut reader io.BufferedReader, length int, path string) ? {
 	mut file := os.create(path) ?
 	defer {