doc: documented new Docker code

src/docker/containers.v

@@ -14,6 +14,7 @@ struct Container {
 	names []string [json: Names]
 }
 
+// containers returns a list of all containers.
 pub fn (mut d DockerDaemon) containers() ?[]Container {
 	d.send_request('GET', urllib.parse('/v1.41/containers/json')?)?
 	head, res := d.read_response()?
@@ -45,6 +46,7 @@ pub:
 	warnings []string [json: Warnings]
 }
 
+// create_container creates a new container with the given config.
 pub fn (mut d DockerDaemon) create_container(c NewContainer) ?CreatedContainer {
 	d.send_request_with_json('POST', urllib.parse('/v1.41/containers/create')?, c)?
 	head, res := d.read_response()?
@@ -60,6 +62,7 @@ pub fn (mut d DockerDaemon) create_container(c NewContainer) ?CreatedContainer {
 	return data
 }
 
+// start_container starts the container with the given id.
 pub fn (mut d DockerDaemon) start_container(id string) ? {
 	d.send_request('POST', urllib.parse('/v1.41/containers/$id/start')?)?
 	head, body := d.read_response()?
@@ -109,6 +112,7 @@ pub mut:
 	end_time   time.Time [skip]
 }
 
+// inspect_container returns detailed information for a given container.
 pub fn (mut d DockerDaemon) inspect_container(id string) ?ContainerInspect {
 	d.send_request('GET', urllib.parse('/v1.41/containers/$id/json')?)?
 	head, body := d.read_response()?
@@ -150,6 +154,7 @@ pub fn inspect_container(id string) ?ContainerInspect {
 	return data
 }
 
+// remove_container removes the container with the given id.
 pub fn (mut d DockerDaemon) remove_container(id string) ? {
 	d.send_request('DELETE', urllib.parse('/v1.41/containers/$id')?)?
 	head, body := d.read_response()?
@@ -168,6 +173,8 @@ pub fn remove_container(id string) ?bool {
 	return res.status_code == 204
 }
 
+// get_container_logs returns a reader object allowing access to the
+// container's logs.
 pub fn (mut d DockerDaemon) get_container_logs(id string) ?&StreamFormatReader {
 	d.send_request('GET', urllib.parse('/v1.41/containers/$id/logs?stdout=true&stderr=true')?)?
 	head := d.read_response_head()?

src/docker/images.v

@@ -9,6 +9,7 @@ pub:
 	id string [json: Id]
 }
 
+// pull_image pulls the given image:tag.
 pub fn (mut d DockerDaemon) pull_image(image string, tag string) ? {
 	d.send_request('POST', urllib.parse('/v1.41/images/create?fromImage=$image&tag=$tag')?)?
 	head := d.read_response_head()?

src/docker/socket.v

@@ -21,6 +21,7 @@ mut:
 	reader &io.BufferedReader
 }
 
+// new_conn creates a new connection to the Docker daemon.
 pub fn new_conn() ?&DockerDaemon {
 	s := unix.connect_stream(docker.socket)?
 
@@ -32,18 +33,22 @@ pub fn new_conn() ?&DockerDaemon {
 	return d
 }
 
+// send_request sends an HTTP request without body.
 pub fn (mut d DockerDaemon) send_request(method string, url urllib.URL) ? {
 	req := '$method $url.request_uri() HTTP/1.1\nHost: localhost\n\n'
 
 	d.socket.write_string(req)?
 }
 
+// send_request_with_body sends an HTTP request with the given body.
 pub fn (mut d DockerDaemon) send_request_with_body(method string, url urllib.URL, content_type string, body string) ? {
 	req := '$method $url.request_uri() HTTP/1.1\nHost: localhost\nContent-Type: $content_type\nContent-Length: $body.len\n\n$body\n\n'
 
 	d.socket.write_string(req)?
 }
 
+// send_request_with_json<T> is a convenience wrapper around
+// send_request_with_body that encodes the input as JSON.
 pub fn (mut d DockerDaemon) send_request_with_json<T>(method string, url urllib.URL, data &T) ? {
 	body := json.encode(data)
 
@@ -52,8 +57,8 @@ pub fn (mut d DockerDaemon) send_request_with_json<T>(method string, url urllib.
 
 // read_response_head consumes the socket's contents until it encounters
 // '\r\n\r\n', after which it parses the response as an HTTP response.
-// Importantly, this function never consumes past the HTTP separator, so the
-// body can be read fully later on.
+// Importantly, this function never consumes the reader past the HTTP
+// separator, so the body can be read fully later on.
 pub fn (mut d DockerDaemon) read_response_head() ?http.Response {
 	mut c := 0
 	mut buf := []u8{len: 4}
@@ -64,21 +69,12 @@ pub fn (mut d DockerDaemon) read_response_head() ?http.Response {
 		res << buf[..c]
 
 		match_len := util.match_array_in_array(buf[..c], docker.http_separator)
-		// mut i := 0
-		// mut match_len := 0
-
-		// for i + match_len < c {
-		//	if buf[i + match_len] == docker.http_separator[match_len] {
-		//		match_len += 1
-		//	} else {
-		//		i += match_len + 1
-		//		match_len = 0
-		//	}
-		//}
 
 		if match_len == 4 {
 			break
-		} else if match_len > 0 {
+		}
+
+		if match_len > 0 {
 			mut buf2 := []u8{len: 4 - match_len}
 			c2 := d.reader.read(mut buf2)?
 			res << buf2[..c2]
@@ -92,6 +88,8 @@ pub fn (mut d DockerDaemon) read_response_head() ?http.Response {
 	return http.parse_response(res.bytestr())
 }
 
+// read_response_body reads `length` bytes from the stream. It can be used when
+// the response encoding isn't chunked to fully read it.
 pub fn (mut d DockerDaemon) read_response_body(length int) ?string {
 	if length == 0 {
 		return ''
@@ -110,6 +108,9 @@ pub fn (mut d DockerDaemon) read_response_body(length int) ?string {
 	return builder.str()
 }
 
+// read_response is a convenience function combining read_response_head &
+// read_response_body. It can be used when you know for certain the response
+// won't be chunked.
 pub fn (mut d DockerDaemon) read_response() ?(http.Response, string) {
 	head := d.read_response_head()?
 	content_length := head.header.get(http.CommonHeader.content_length)?.int()
@@ -118,12 +119,16 @@ pub fn (mut d DockerDaemon) read_response() ?(http.Response, string) {
 	return head, res
 }
 
+// get_chunked_response_reader returns a ChunkedResponseReader using the socket
+// as reader.
 pub fn (mut d DockerDaemon) get_chunked_response_reader() &ChunkedResponseReader {
 	r := new_chunked_response_reader(d.reader)
 
 	return r
 }
 
+// get_stream_format_reader returns a StreamFormatReader using the socket as
+// reader.
 pub fn (mut d DockerDaemon) get_stream_format_reader() &StreamFormatReader {
 	r := new_chunked_response_reader(d.reader)
 	r2 := new_stream_format_reader(r)

src/docker/stream.v

@@ -5,6 +5,8 @@ import util
 import encoding.binary
 import encoding.hex
 
+// ChunkedResponseReader parses an underlying HTTP chunked response, exposing
+// it as if it was a continuous stream of data.
 struct ChunkedResponseReader {
 mut:
 	reader              io.Reader
@@ -13,6 +15,8 @@ mut:
 	started             bool
 }
 
+// new_chunked_response_reader creates a new ChunkedResponseReader on the heap
+// with the provided reader.
 pub fn new_chunked_response_reader(reader io.Reader) &ChunkedResponseReader {
 	r := &ChunkedResponseReader{
 		reader: reader
@@ -21,7 +25,7 @@ pub fn new_chunked_response_reader(reader io.Reader) &ChunkedResponseReader {
 	return r
 }
 
-// We satisfy the io.Reader interface
+// read satisfies the io.Reader interface.
 pub fn (mut r ChunkedResponseReader) read(mut buf []u8) ?int {
 	if r.end_of_stream {
 		return none
@@ -37,6 +41,8 @@ pub fn (mut r ChunkedResponseReader) read(mut buf []u8) ?int {
 
 	mut c := 0
 
+	// Make sure we don't read more than we can safely read. This is to avoid
+	// the underlying reader from becoming out of sync with our parsing:
 	if buf.len > r.bytes_left_in_chunk {
 		c = r.reader.read(mut buf[..r.bytes_left_in_chunk])?
 	} else {
@@ -48,6 +54,9 @@ pub fn (mut r ChunkedResponseReader) read(mut buf []u8) ?int {
 	return c
 }
 
+// read_chunk_size advances the reader & reads the size of the next HTTP chunk.
+// This function should only be called if the previous chunk has been
+// completely consumed.
 fn (mut r ChunkedResponseReader) read_chunk_size() ?u64 {
 	mut buf := []u8{len: 2}
 	mut res := []u8{}
@@ -80,6 +89,7 @@ fn (mut r ChunkedResponseReader) read_chunk_size() ?u64 {
 		}
 	}
 
+	// The length of the next chunk is provided as a hexadecimal
 	mut num_data := hex.decode(res#[..-2].bytestr())?
 
 	for num_data.len < 8 {
@@ -88,6 +98,8 @@ fn (mut r ChunkedResponseReader) read_chunk_size() ?u64 {
 
 	num := binary.big_endian_u64(num_data)
 
+	// This only occurs for the very last chunk, which always reports a size of
+	// 0.
 	if num == 0 {
 		r.end_of_stream = true
 	}
@@ -95,16 +107,17 @@ fn (mut r ChunkedResponseReader) read_chunk_size() ?u64 {
 	return num
 }
 
+// StreamFormatReader parses an underlying stream of Docker logs, removing the
+// header bytes.
 struct StreamFormatReader {
-	stdout bool
-	stderr bool
-	stdin  bool
 mut:
 	reader              io.Reader
 	bytes_left_in_chunk u32
 	end_of_stream       bool
 }
 
+// new_stream_format_reader creates a new StreamFormatReader using the given
+// reader.
 pub fn new_stream_format_reader(reader io.Reader) &StreamFormatReader {
 	r := &StreamFormatReader{
 		reader: reader
@@ -113,6 +126,7 @@ pub fn new_stream_format_reader(reader io.Reader) &StreamFormatReader {
 	return r
 }
 
+// read satisfies the io.Reader interface.
 pub fn (mut r StreamFormatReader) read(mut buf []u8) ?int {
 	if r.end_of_stream {
 		return none
@@ -139,6 +153,8 @@ pub fn (mut r StreamFormatReader) read(mut buf []u8) ?int {
 	return c
 }
 
+// read_chunk_size advances the reader & reads the header bytes for the length
+// of the next chunk.
 fn (mut r StreamFormatReader) read_chunk_size() ?u32 {
 	mut buf := []u8{len: 8}
 

src/util/util.v

@@ -93,6 +93,9 @@ pub fn pretty_bytes(bytes int) string {
 	return '${n:.2}${util.prefixes[i]}'
 }
 
+// match_array_in_array<T> returns how many elements of a2 overlap with a1. For
+// example, if a1 = "abcd" & a2 = "cd", the result will be 2. If the match is
+// not at the end of a1, the result is 0.
 pub fn match_array_in_array<T>(a1 []T, a2 []T) int {
 	mut i := 0
 	mut match_len := 0