tinysql::anonymous_namespace{Server.cpp} Namespace Reference

Classes
struct	Request
	One HTTP request, split into the parts the server uses. More...
class	Socket
	Owns a socket descriptor and closes it when it goes out of scope (RAII). More...

Functions
void	throwSystemError (std::string_view what)
	Throws the error of the last failed system call.
std::string_view	headerValue (std::string_view head, std::string_view name)
	Finds a header's value in the raw request, ignoring the case of its name.
Request	readRequest (int fd)
	Reads one HTTP request: the request line, the headers and, if there is one, the body.
void	sendAll (int fd, std::string_view data)
	Sends all of data, retrying until it is written or the client goes away.
std::string	httpResponse (std::string_view status, std::string_view contentType, std::string_view body)
	Builds a complete HTTP response.
std::string	errorResponse (std::string_view status, std::string_view message)
	Builds a JSON error answer, e.g. {"error":"Not found"}.
std::string_view	contentTypeFor (std::string_view name)
	The content type of a file of the page, from its extension.
bool	isSafeFileName (std::string_view name)
	Tells whether a requested file name is safe to serve from the web/ directory.
std::string	serveFile (const ServerConfig &config, std::string_view name)
	Serves one file of the page from the web/ directory.
std::string	runSql (const ServerConfig &config, std::string_view sql)
	Runs the SQL of a POST /api/sql request, logs it, and builds the JSON answer.
std::string	listTables (const ServerConfig &config)
	Builds the JSON answer of GET /api/tables. Call it only while holding workMutex.
std::string	clientAddress (const sockaddr_in &address)
	Formats a client's IPv4 address.
void	handleClient (const ServerConfig &config, int fd, const std::string &client)
	Serves one connection: reads the request, answers it, and closes.

Variables
constexpr std::size_t	kMaxRequestSize = 64 * 1024
	The largest request read (headers and body), in bytes; the rest is ignored.
constexpr int	kIdleSeconds = 30
	How long a connection may stay silent before it is closed, in seconds.
std::mutex	workMutex
	Lets only one request at a time run SQL and write to the console.

Function Documentation

clientAddress()

std::string tinysql::anonymous_namespace{Server.cpp}::clientAddress

(

const sockaddr_in &

address

)

Formats a client's IPv4 address.

Parameters

address

The address returned by accept().

Returns

The address as text, e.g. "192.168.1.10".

Definition at line 264 of file Server.cpp.

contentTypeFor()

std::string_view tinysql::anonymous_namespace{Server.cpp}::contentTypeFor

(

std::string_view

name

)

The content type of a file of the page, from its extension.

Parameters

name	The file name, e.g. "app.js".

Returns

The type to send in the Content-Type header.

Definition at line 193 of file Server.cpp.

errorResponse()

std::string tinysql::anonymous_namespace{Server.cpp}::errorResponse	(	std::string_view	status,
		std::string_view	message
	)

Builds a JSON error answer, e.g. {"error":"Not found"}.

Parameters

status	The status line's code and text, e.g. "404 Not Found".
message	The error message.

Returns

The response.

Definition at line 185 of file Server.cpp.

handleClient()

void tinysql::anonymous_namespace{Server.cpp}::handleClient	(	const ServerConfig &	config,
		int	fd,
		const std::string &	client
	)

Serves one connection: reads the request, answers it, and closes.

The routes:

• GET / and GET /<file>: the page, from the web/ directory;
• GET /api/tables: the tables and their columns, as JSON;
• POST /api/sql: runs the SQL in the body, answers with the results as JSON.

A connection that sends nothing is closed without an answer; a POST elsewhere gets 404, other methods 405.

Parameters

config	The server settings.
fd	The connection.
client	The client's address, for the log.

Definition at line 282 of file Server.cpp.

headerValue()

std::string_view tinysql::anonymous_namespace{Server.cpp}::headerValue	(	std::string_view	head,
		std::string_view	name
	)

Finds a header's value in the raw request, ignoring the case of its name.

Parameters

head	The request line and headers.
name	The header name, e.g. "content-length".

Returns

The value without surrounding spaces, or an empty view if the header is missing.

Definition at line 95 of file Server.cpp.

httpResponse()

std::string tinysql::anonymous_namespace{Server.cpp}::httpResponse	(	std::string_view	status,
		std::string_view	contentType,
		std::string_view	body
	)

Builds a complete HTTP response.

Parameters

status	The status line's code and text, e.g. "200 OK".
contentType	The type of the body, e.g. "application/json".
body	The body.

Returns

The response, headers included. no-cache makes the browser ask again each time, so a change to a file in web/ shows up on the next reload.

Definition at line 174 of file Server.cpp.

isSafeFileName()

bool tinysql::anonymous_namespace{Server.cpp}::isSafeFileName

(

std::string_view

name

)

Tells whether a requested file name is safe to serve from the web/ directory.

Parameters

name	The name, without the leading /.

Returns

True for plain names such as app.js: letters, digits, ., - and _, not starting with .. This rules out .. and /, so no request can reach a file outside web/.

Definition at line 207 of file Server.cpp.

listTables()

std::string tinysql::anonymous_namespace{Server.cpp}::listTables

(

const ServerConfig &

config

)

Builds the JSON answer of GET /api/tables. Call it only while holding workMutex.

Parameters

config

The server settings.

Returns

The response, or a 500 error if SYSTEM_TABLE cannot be read.

Definition at line 252 of file Server.cpp.

readRequest()

Request tinysql::anonymous_namespace{Server.cpp}::readRequest

(

int

fd

)

Reads one HTTP request: the request line, the headers and, if there is one, the body.

Parameters

fd	The connection.

Returns

The request. Its method is empty if the client sent nothing before the idle timeout, and the body is cut at kMaxRequestSize bytes.

Definition at line 115 of file Server.cpp.

runSql()

std::string tinysql::anonymous_namespace{Server.cpp}::runSql	(	const ServerConfig &	config,
		std::string_view	sql
	)

Runs the SQL of a POST /api/sql request, logs it, and builds the JSON answer.

Call it only while holding workMutex.

Parameters

config	The server settings.
sql	The statements, as sent in the request body.

Returns

The response.

Definition at line 238 of file Server.cpp.

sendAll()

void tinysql::anonymous_namespace{Server.cpp}::sendAll	(	int	fd,
		std::string_view	data
	)

Sends all of data, retrying until it is written or the client goes away.

Parameters

fd	The connection.
data	The bytes to send.

Definition at line 157 of file Server.cpp.

serveFile()

std::string tinysql::anonymous_namespace{Server.cpp}::serveFile	(	const ServerConfig &	config,
		std::string_view	name
	)

Serves one file of the page from the web/ directory.

Parameters

config	The server settings.
name	The file name; index.html for the page itself.

Returns

The response: the file, or 404 if the name is not safe or the file does not exist.

Definition at line 218 of file Server.cpp.

throwSystemError()

void tinysql::anonymous_namespace{Server.cpp}::throwSystemError

(

std::string_view

what

)

Throws the error of the last failed system call.

Parameters

what	What was being done, e.g. "bind to port 8080".

Exceptions

std::system_error

Always, with the current errno.

Definition at line 79 of file Server.cpp.

Variable Documentation

kIdleSeconds

constexpr int tinysql::anonymous_namespace{Server.cpp}::kIdleSeconds = 30

constexpr

How long a connection may stay silent before it is closed, in seconds.

Browsers open connections early ("preconnect") and may send nothing on them for several seconds.

Definition at line 38 of file Server.cpp.

kMaxRequestSize

constexpr std::size_t tinysql::anonymous_namespace{Server.cpp}::kMaxRequestSize = 64 * 1024

constexpr

The largest request read (headers and body), in bytes; the rest is ignored.

Definition at line 33 of file Server.cpp.

workMutex

std::mutex tinysql::anonymous_namespace{Server.cpp}::workMutex

Lets only one request at a time run SQL and write to the console.

Each connection is read in its own thread; this lock keeps the table files and the log from being mixed up.

Definition at line 43 of file Server.cpp.