php: Move server code into new phpx package

This commit is contained in:
Tom Wiesing 2022-10-19 13:52:24 +02:00
parent 4df5f6387c
commit 2e47626900
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13 changed files with 134 additions and 86 deletions

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@ -1,216 +0,0 @@
package phpserver
import (
"context"
"encoding/json"
"io"
"os"
"strings"
"sync"
_ "embed"
"github.com/tkw1536/goprogram/lib/collection"
"github.com/tkw1536/goprogram/lib/nobufio"
"github.com/tkw1536/goprogram/stream"
)
// New creates a new server, with execPHP as a method to call a PHP Shell.
func New(execPHP func(str stream.IOStream, script string)) (*Server, error) {
// create input and output pipes
ir, iw, err := os.Pipe()
if err != nil {
return nil, ServerError{errPHPInit, err}
}
or, ow, err := os.Pipe()
if err != nil {
ir.Close()
iw.Close()
return nil, ServerError{errPHPInit, err}
}
// create a context to close the server
context, cancel := context.WithCancel(context.Background())
// start the shell process, which will close everything once done
go func() {
defer func() {
ir.Close()
iw.Close()
or.Close()
ow.Close()
cancel()
}()
// start the server
io := stream.NewIOStream(ow, nil, ir, 0)
execPHP(io, serverPHP)
}()
// return a new server
return &Server{
in: iw,
out: or,
c: context,
}, nil
}
// Server represents a server that executes code within a distillery.
// A typical use-case is to define functions using [MarshalEval], and then call those functions [MarshalCall].
//
// A nil Server will return [ErrServerBroken] on every function call.
type Server struct {
m sync.Mutex
in io.WriteCloser
out io.Reader
c context.Context
}
// MarshalEval evaluates code on the server and Marshals the result into value.
// When value is nil, the results are discarded.
//
// code is directly passed to php's "eval" function.
// as such any functions defined will remain in server memory.
//
// When an exception is thrown by the PHP Code, error is not nil, and dest remains unchanged.
func (server *Server) MarshalEval(value any, code string) error {
server.m.Lock()
defer server.m.Unlock()
// quick hack: when the server is already done
if err := server.c.Err(); err != nil {
return errPHPClosed
}
// find a delimiter for the code, and then send
delim := findDelimiter(code)
io.WriteString(server.in, delim+"\n"+code+"\n"+delim+"\n")
// read the next line (as a response)
data, err := nobufio.ReadLine(server.out)
if err != nil {
return ServerError{Message: errPHPReceive, Err: err}
}
// read whatever we received
var received [2]json.RawMessage
if err := json.Unmarshal([]byte(data), &received); err != nil {
return ServerError{Message: errPHPMarshal, Err: err}
}
// check if there was an error
var errString string
if err := json.Unmarshal(received[1], &errString); err == nil && errString != "" {
return Throwable(errString)
}
// special case: no return value => no unmarshaling needed
if value == nil {
return nil
}
// read the actual result!
return json.Unmarshal(received[0], value)
}
// Eval is like [MarshalEval], but returns the value as an any
func (server *Server) Eval(code string) (value any, err error) {
err = server.MarshalEval(&value, code)
return
}
// MarshalCall calls a previously defined function with the given arguments.
// Arguments are sent to php using json Marshal, and are 'json_decode'd on the php side.
//
// Return values are received as in [MarshalEval].
func (server *Server) MarshalCall(value any, function string, args ...any) error {
// name of function to call
name := MarshalString(function)
// generate code to call
var code string
switch len(args) {
case 0:
code = "return call_user_func(" + name + ");"
case 1:
param, err := Marshal(args[0])
if err != nil {
return err
}
code = "return call_user_func(" + name + "," + param + ");"
default:
params, err := Marshal(args)
if err != nil {
return err
}
code = "return call_user_func_array(" + name + "," + params + ");"
}
// and evaluate the code
return server.MarshalEval(value, code)
}
// Call is like [MarshalCall] but returns the return value of the function as an any
func (server *Server) Call(function string, args ...any) (value any, err error) {
err = server.MarshalCall(&value, function, args...)
return
}
const delimiterRune = 'F' // press to pay respect
// findDelimiter finds a delimiter that does not occur in the input string
func findDelimiter(input string) string {
// find the longest sequence of delimiter rune
var current, longest int
for _, r := range input {
if r == delimiterRune {
current++
} else {
current = 0
}
if current > longest {
longest = current
}
}
// and then return it multipled longer than that
return strings.Repeat(string(delimiterRune), longest+1)
}
// Close closes this server and prevents any further code from being run.
func (server *Server) Close() error {
server.m.Lock()
defer server.m.Unlock()
// if the context is already closed
if err := server.c.Err(); err != nil {
return errPHPClosed
}
server.in.Close()
<-server.c.Done()
return nil
}
//go:embed server.php
var serverPHP string
// pre-process the server.php code to make it shorter
func init() {
// remove the first '<?php' line
lines := strings.Split(serverPHP, "\n")[1:]
for i, line := range lines {
lines[i] = strings.TrimSpace(line)
}
// remove comment lines
lines = collection.Filter(lines, func(line string) bool {
return !strings.HasPrefix(line, "//")
})
serverPHP = strings.Join(lines, "")
}