railpack

1package plan2 3import (4	"encoding/json"5	"fmt"6	"os"7	"strings"8)9 10type Command interface {11	CommandType() string12	Spreadable13}14 15type ExecOptions struct {16	CustomName string17}18 19// ExecCommand represents a shell command to be executed during the build20type ExecCommand struct {21	Cmd        string `json:"cmd" jsonschema:"description=The shell command to execute (e.g. 'go build' or 'npm install')"`22	CustomName string `json:"customName,omitempty" jsonschema:"description=Optional custom name to display for this command in build output"`23}24 25// PathCommand represents adding a directory to the global PATH environment variable26type PathCommand struct {27	Path string `json:"path" jsonschema:"description=Directory path to add to the global PATH environment variable. This path will be available to all subsequent commands in the build"`28}29 30// CopyCommand represents copying files or directories during the build31type CopyCommand struct {32	Image string `json:"image,omitempty" jsonschema:"description=Optional source image to copy from. This can be any public image URL"`33	Src   string `json:"src" jsonschema:"description=Source path to copy from. Can be a file or directory"`34	Dest  string `json:"dest" jsonschema:"description=Destination path to copy to. Will be created if it doesn't exist"`35}36 37type FileOptions struct {38	Mode       os.FileMode39	CustomName string40}41 42// FileCommand represents creating or modifying a file during the build43type FileCommand struct {44	Path       string      `json:"path" jsonschema:"description=Directory path where the file should be created"`45	Name       string      `json:"name" jsonschema:"description=Name of the file to create"`46	Mode       os.FileMode `json:"mode,omitempty" jsonschema:"description=Optional Unix file permissions mode (e.g. 0644 for regular file)"`47	CustomName string      `json:"customName,omitempty" jsonschema:"description=Optional custom name to display for this file operation"`48}49 50func (e ExecCommand) CommandType() string { return "exec" }51func (g PathCommand) CommandType() string { return "globalPath" }52func (c CopyCommand) CommandType() string { return "copy" }53func (f FileCommand) CommandType() string { return "file" }54 55func NewExecCommand(cmd string, options ...ExecOptions) Command {56	exec := ExecCommand{Cmd: cmd}57	if len(options) > 0 {58		exec.CustomName = options[0].CustomName59	}60	return exec61}62 63func ShellCommandString(cmd string) string {64	return "sh -c '" + cmd + "'"65}66 67func NewExecShellCommand(cmd string, options ...ExecOptions) Command {68	if len(options) == 0 {69		options = []ExecOptions{70			{CustomName: cmd},71		}72	}73 74	exec := NewExecCommand(ShellCommandString(cmd), options...)75	return exec76}77 78func NewPathCommand(path string, customName ...string) Command {79	pathCmd := PathCommand{Path: path}80	return pathCmd81}82 83func NewCopyCommand(src string, dst ...string) Command {84	dstPath := src85	if len(dst) > 0 {86		dstPath = dst[0]87	}88 89	copyCmd := CopyCommand{Src: src, Dest: dstPath}90	return copyCmd91}92 93func NewFileCommand(path, name string, options ...FileOptions) Command {94	fileCmd := FileCommand{Path: path, Name: name}95	if len(options) > 0 {96		fileCmd.CustomName = options[0].CustomName97		fileCmd.Mode = options[0].Mode98	}99	return fileCmd100}101 102func UnmarshalCommand(data []byte) (Command, error) {103	// First try to unmarshal as JSON object104	if cmd, err := UnmarshalJsonCommand(data); err == nil {105		return cmd, nil106	}107 108	// If that fails, parse the string into a command109	return UnmarshalStringCommand(data)110}111 112func UnmarshalJsonCommand(data []byte) (Command, error) {113	// Try to unmarshal as JSON object114	var rawMap map[string]any115	if err := json.Unmarshal(data, &rawMap); err != nil {116		return nil, err117	}118 119	// Determine command type based on fields present120	if _, ok := rawMap["cmd"]; ok {121		var cmd ExecCommand122		if err := json.Unmarshal(data, &cmd); err != nil {123			return nil, err124		}125		return cmd, nil126	}127 128	if _, ok := rawMap["path"]; ok {129		if _, ok := rawMap["name"]; ok {130			var file FileCommand131			if err := json.Unmarshal(data, &file); err != nil {132				return nil, err133			}134			return file, nil135		}136		var path PathCommand137		if err := json.Unmarshal(data, &path); err != nil {138			return nil, err139		}140		return path, nil141	}142 143	if _, ok := rawMap["src"]; ok {144		var copy CopyCommand145		if err := json.Unmarshal(data, &copy); err != nil {146			return nil, err147		}148		return copy, nil149	}150 151	return nil, fmt.Errorf("unknown command type: %v", rawMap)152}153 154func UnmarshalStringCommand(data []byte) (Command, error) {155	str := string(data)156 157	// If no prefix, treat as exec command158	if !strings.Contains(str, ":") {159		cmdToRun := strings.Trim(str, "\"")160		return NewExecShellCommand(cmdToRun, ExecOptions{CustomName: cmdToRun}), nil161	}162 163	parts := strings.SplitN(str, ":", 2)164	if len(parts) != 2 {165		return nil, fmt.Errorf("invalid command format: %s", str)166	}167 168	prefix := parts[0]169	payload := parts[1]170 171	// Split prefix into command type and custom name172	prefixParts := strings.SplitN(prefix, "#", 2)173	cmdType := prefixParts[0]174	customName := ""175	if len(prefixParts) > 1 {176		customName = prefixParts[1]177	}178 179	switch cmdType {180	case "RUN":181		return NewExecShellCommand(payload, ExecOptions{CustomName: customName}), nil182	case "PATH":183		return NewPathCommand(payload), nil184	case "COPY":185		copyParts := strings.Fields(payload)186		if len(copyParts) != 2 {187			return nil, fmt.Errorf("invalid COPY format: %s", payload)188		}189		return NewCopyCommand(copyParts[0], copyParts[1]), nil190	case "FILE":191		fileParts := strings.Fields(payload)192		if len(fileParts) != 2 {193			return nil, fmt.Errorf("invalid FILE format: %s", payload)194		}195		return NewFileCommand(fileParts[0], fileParts[1], FileOptions{CustomName: customName}), nil196	}197 198	// fallback to exec command type199	cmdToRun := strings.Trim(str, "\"")200	if customName == "" {201		customName = cmdToRun202	}203	return NewExecShellCommand(cmdToRun, ExecOptions{CustomName: customName}), nil204}205 206func (e ExecCommand) IsSpread() bool {207	return e.Cmd == ShellCommandString("...") || e.Cmd == "..."208}209 210func (p PathCommand) IsSpread() bool {211	return false212}213 214func (c CopyCommand) IsSpread() bool {215	return false216}217 218func (f FileCommand) IsSpread() bool {219	return false220}221