cmd_remote.v

1//! `koh remote` — the machine's remote, set up once and used by every repo.2//!3//! Setup is interactive by default, because it ends with a live connection4//! test: a remote is only saved once it has proved it can store an object and5//! refuse to overwrite it. `folder` and `s3` forms are available for a machine6//! being set up by a script, and an agent can read the current setting with7//! `--json` (which never prints the secret key).89module cli1011import json212import net.http13import net.urllib14import os15import src.exchange16import src.fmt17import src.machine18import src.remote19import src.storage20import term.termios2122pub fn cmd_remote(raw []string) int {23	args := parse('remote', raw, Options{24		values: ['code']25		flags:  ['json', 'forget']26	}) or { return usage_error(err.msg()) }27	// A repo stolen from a Kepr has an address of its own, and it belongs above the machine's — as28	// a line for a person: `--json` stays one document.29	if !args.json() {30		if _ := storage.find_root(os.getwd()) {31			store := open_store() or { return refuse(args.json(), err.msg()) }32			defer {33				store.close()34			}35			source := exchange.source_of(store)36			if source != '' {37				println('  ${fmt.muted('source:')} ${source} ${fmt.muted('(read-only)')}')38			}39		}40	}41	if args.value('code') != '' && args.positional.len == 0 {42		return usage_error('--code belongs to "koh remote <host>"')43	}44	if args.flag('forget') {45		if !machine.has_remote() {46			return refuse(args.json(), 'this machine has no remote to forget')47		}48		machine.forget_remote() or { return refuse(args.json(), err.msg()) }49		if args.json() {50			emit_json(json2.encode(RemoteJson{51				configured: false52			}))53			return 054		}55		ok("forgot this machine's remote")56		return 057	}58	if args.positional.len == 0 {59		if !machine.has_remote() {60			if args.json() {61				emit_json(json2.encode(RemoteJson{62					configured: false63				}))64				return 065			}66			return setup_wizard()67		}68		settings := machine.load_remote() or {69			// Otherwise the message to run "koh remote" again would loop.70			if !args.json() && interactive() {71				warn(err.msg())72				return setup_wizard()73			}74			return refuse(args.json(), err.msg())75		}76		if args.json() {77			emit_json(json2.encode(RemoteJson{78				configured: true79				kind:       settings.kind80				target:     describe(settings)81			}))82			return 083		}84		ok('remote: ${describe(settings)}')85		if !interactive() {86			note('run "koh remote folder <path>" or "koh remote s3 <endpoint> <bucket> <region>" to replace it')87			return 088		}89		print('  replace it? [y/N] ')90		if os.get_line().trim_right('\r') != 'y' {91			return 092		}93		// The old remote stays until the new one passes its test.94		return setup_wizard()95	}96	// A non-interactive form, still tested before it is saved.97	return set_remote(args)98}99100fn set_remote(args Args) int {101	if args.positional_at(0) !in [machine.kind_folder, machine.kind_s3] {102		return set_kepr_remote(args)103	}104	if args.value('code') != '' {105		return usage_error('--code belongs to "koh remote <host>", not to folder or s3')106	}107	kind := args.positional_at(0)108	match kind {109		machine.kind_folder {110			path := args.positional_at(1)111			if path == '' {112				return usage_error('remote folder needs a path: koh remote folder /Volumes/usb/koh')113			}114			settings := machine.RemoteSettings{115				kind: machine.kind_folder116				path: os.real_path(path)117			}118			return save_after_check(settings, args, '', '')119		}120		machine.kind_s3 {121			endpoint := args.positional_at(1)122			bucket := args.positional_at(2)123			region := args.positional_at(3)124			if endpoint == '' || bucket == '' || region == '' {125				return usage_error('remote s3 needs an endpoint, bucket and region: koh remote s3 https://s3.fr-par.scw.cloud my-bucket fr-par')126			}127			access_key, secret_key := s3_keys() or { return refuse(args.json(), err.msg()) }128			settings := machine.RemoteSettings{129				kind:     machine.kind_s3130				endpoint: endpoint131				bucket:   bucket132				region:   region133			}134			return save_after_check(settings, args, access_key, secret_key)135		}136		else {137			return usage_error('remote takes "folder", "s3", or a Kepr host')138		}139	}140}141142fn set_kepr_remote(args Args) int {143	if args.positional.len != 1 {144		return usage_error('koh remote <host> accepts one Kepr host')145	}146	host := remote.kepr_host(args.positional_at(0)) or { return refuse(args.json(), err.msg()) }147	connect_url := '${host}/connect?machine=${urllib.query_escape(machine.name())}'148	println('Open ${connect_url} and sign in')149	mut code := args.value('code')150	if code == '' {151		if !interactive() {152			return fail('setting up a Kepr remote needs a terminal, or use --code <code>')153		}154		// Only a person about to type the code gets a browser opened for them: with `--code` the155		// page has been read already, and a script must never take over the desktop. `open` or156		// `xdg-open` is launched with an argument vector rather than a shell — neither the host nor157		// this machine's name is ours to quote for one — and a browser that will not open is not158		// an error.159		mut browser := os.new_process(if os.user_os() == 'macos' { 'open' } else { 'xdg-open' })160		browser.set_args([connect_url])161		browser.run()162		print('paste the code: ')163		code = os.get_line().trim_space()164	}165	// Redirects are refused: a 3xx would hand the one-time code to whatever it points at.166	response := http.fetch(167		url:            '${host}/api/connect'168		method:         .post169		header:         http.new_header(170			key:   .content_type171			value: 'application/x-www-form-urlencoded'172		)173		data:           'code=${urllib.query_escape(code)}'174		enable_http2:   false175		allow_redirect: false176	) or { return refuse(args.json(), 'could not reach Kepr: ${err.msg()}') }177	if response.status_code == 404 {178		// One 404 covers a wrong code, an expired one, and a Kepr that hands out nothing. The two179		// are told apart by asking for the connect page: 302 means the endpoint is there.180		probe := http.fetch(181			url:            connect_url182			method:         .get183			enable_http2:   false184			allow_redirect: false185		) or {186			return refuse(args.json(), 'that code is wrong or has expired — nothing was changed')187		}188		if probe.status_code == 404 {189			return refuse(args.json(), 'this Kepr doesn\'t hand out bucket access; use "koh remote s3"')190		}191		if probe.status_code != 302 {192			return refuse(args.json(), 'this Kepr answered ${probe.status_code} for its connect page — nothing was changed')193		}194		return refuse(args.json(), 'that code is wrong or has expired — nothing was changed')195	}196	if response.status_code != 200 {197		return refuse(args.json(), 'Kepr refused the code (${response.status_code}) — nothing was changed')198	}199	reply := json2.decode[KeprReply](response.body) or {200		return refuse(args.json(), 'Kepr returned an invalid response — nothing was changed')201	}202	if reply.endpoint == '' || reply.bucket == '' || reply.region == ''203		|| reply.access_key_id == '' || reply.secret_access_key == '' {204		return refuse(args.json(), 'Kepr returned incomplete settings — nothing was changed')205	}206	settings := machine.RemoteSettings{207		kind:     machine.kind_s3208		endpoint: reply.endpoint209		bucket:   reply.bucket210		region:   reply.region211		kepr:     host212	}213	return save_after_check(settings, args, reply.access_key_id, reply.secret_access_key)214}215216// save_after_check is the whole point: nothing is written to ~/.config/koh217// until the remote has passed the test.218fn save_after_check(settings machine.RemoteSettings, args Args, access_key string, secret_key string) int {219	mut backend := build_backend(settings, access_key, secret_key) or {220		return refuse(args.json(), err.msg())221	}222	remote.check(mut backend) or {223		return refuse(args.json(), 'the remote did not pass its test: ${err.msg()}')224	}225	machine.save_remote(settings) or { return refuse(args.json(), err.msg()) }226	if settings.kind == machine.kind_s3 {227		machine.save_credentials(machine.Credentials{228			access_key: access_key229			secret_key: secret_key230		}) or { return refuse(args.json(), err.msg()) }231	}232	if args.json() {233		emit_json(json2.encode(RemoteJson{234			configured: true235			kind:       settings.kind236			target:     describe(settings)237		}))238		return 0239	}240	ok('remote set to ${describe(settings)}')241	note('every repo on this machine now offers to it')242	return 0243}244245fn build_backend(settings machine.RemoteSettings, access_key string, secret_key string) !remote.Backend {246	if settings.kind == machine.kind_folder {247		return remote.new_folder(settings.path)!248	}249	return remote.new_s3(settings.endpoint, settings.bucket, settings.region, access_key,250		secret_key)!251}252253fn setup_wizard() int {254	if !interactive() {255		return fail('setting up a remote needs a terminal, or use: koh remote folder <path>, koh remote s3 <endpoint> <bucket> <region>')256	}257	println('  choose a remote:')258	println('    ${fmt.amber('1')} folder   a directory, on a disk or a NAS')259	println('    ${fmt.amber('2')} s3       an S3-compatible bucket')260	print('  which? [1] ')261	if os.get_line().trim_space() == '2' {262		return wizard_s3()263	}264	print('  folder path: ')265	path := os.get_line().trim_space()266	if path == '' {267		return fail('no path given — nothing was saved')268	}269	settings := machine.RemoteSettings{270		kind: machine.kind_folder271		path: os.real_path(path)272	}273	return save_after_check(settings, Args{}, '', '')274}275276fn wizard_s3() int {277	print('  endpoint [https://s3.fr-par.scw.cloud]: ')278	endpoint := or_default(os.get_line().trim_space(), 'https://s3.fr-par.scw.cloud')279	print('  bucket: ')280	bucket := os.get_line().trim_space()281	print('  region [fr-par]: ')282	region := or_default(os.get_line().trim_space(), 'fr-par')283	if bucket == '' {284		return fail('no bucket given — nothing was saved')285	}286	access_key, secret_key := s3_keys() or { return fail(err.msg()) }287	settings := machine.RemoteSettings{288		kind:     machine.kind_s3289		endpoint: endpoint290		bucket:   bucket291		region:   region292	}293	return save_after_check(settings, Args{}, access_key, secret_key)294}295296// s3_keys takes the keys from the environment when a script supplies them, and297// otherwise asks, so they never have to be typed into a shell history.298fn s3_keys() !(string, string) {299	access_key := os.getenv('KOH_ACCESS_KEY')300	secret_key := os.getenv('KOH_SECRET_KEY')301	if access_key != '' && secret_key != '' {302		return access_key, secret_key303	}304	if !interactive() {305		return error('S3 keys are missing — set KOH_ACCESS_KEY and KOH_SECRET_KEY, or run koh remote on a terminal')306	}307	print('  access key: ')308	access_key_typed := os.get_line().trim_space()309	// Hidden input needs a terminal on both ends; with output redirected, the310	// key is read like any other line.311	mut secret_key_typed := ''312	mut saved := termios.Termios{}313	if os.is_atty(1) != 0 && os.getenv('TERM') != 'dumb' && termios.tcgetattr(0, mut saved) == 0 {314		// V's hidden read returns on end of input without turning echo back315		// on, so the terminal's state is kept here and put back. A failed316		// read is an empty key, which is refused below.317		secret_key_typed = os.input_password('  secret key: ') or {318			println('')319			if termios.set_state(0, saved) != 0 {320				warn('the terminal may no longer echo — run "stty sane"')321			}322			''323		}324	} else {325		print('  secret key: ')326		secret_key_typed = os.get_line()327	}328	secret_key_typed = secret_key_typed.trim_space()329	if access_key_typed == '' || secret_key_typed == '' {330		return error('both keys are needed — nothing was saved')331	}332	return access_key_typed, secret_key_typed333}334335fn describe(settings machine.RemoteSettings) string {336	if settings.kind == machine.kind_folder {337		return 'folder ${settings.path}'338	}339	return 's3 ${settings.endpoint}/${settings.bucket} (${settings.region})'340}341342fn or_default(value string, fallback string) string {343	return if value == '' { fallback } else { value }344}345346struct RemoteJson {347	configured bool348	kind       string349	target     string350}351352struct KeprReply {353	endpoint          string354	bucket            string355	region            string356	access_key_id     string357	secret_access_key string358}