knative.dev/pkg@v0.0.0-20260602142205-ac97e43f6622/test/upgrade/shell/project.go (about)

     1  /*
     2  Copyright 2020 The Knative Authors
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8      http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  package shell
    18  
    19  import (
    20  	"errors"
    21  	"fmt"
    22  	"path"
    23  	"regexp"
    24  	"runtime"
    25  )
    26  
    27  var (
    28  	// ErrCantGetCaller is raised when we can't calculate a caller of NewProjectLocation.
    29  	ErrCantGetCaller = errors.New("can't get caller")
    30  
    31  	// ErrCallerNotAllowed is raised when user tries to use this shell-out package
    32  	// outside of allowed places. This package is deprecated from start and was
    33  	// introduced to allow rewriting of shell code to Golang in small chunks.
    34  	ErrCallerNotAllowed = errors.New("don't try use knative.dev/pkg/test/upgrade/shell package outside of allowed places")
    35  )
    36  
    37  // NewProjectLocation creates a ProjectLocation that is used to calculate
    38  // relative paths within the project.
    39  func NewProjectLocation(pathToRoot string) (ProjectLocation, error) {
    40  	pc, filename, _, ok := runtime.Caller(1)
    41  	if !ok {
    42  		return nil, ErrCantGetCaller
    43  	}
    44  	funcName := runtime.FuncForPC(pc).Name()
    45  	err := isCallsiteAllowed(funcName)
    46  	if err != nil {
    47  		return nil, err
    48  	}
    49  	return &callerLocation{
    50  		caller:     filename,
    51  		pathToRoot: pathToRoot,
    52  	}, nil
    53  }
    54  
    55  // RootPath return a path to root of the project.
    56  func (c *callerLocation) RootPath() string {
    57  	return path.Join(path.Dir(c.caller), c.pathToRoot)
    58  }
    59  
    60  // callerLocation holds a caller Go file, and a relative location to a project
    61  // root directory. This information can be used to calculate relative paths and
    62  // properly source shell scripts.
    63  type callerLocation struct {
    64  	caller     string
    65  	pathToRoot string
    66  }
    67  
    68  func isCallsiteAllowed(funcName string) error {
    69  	validPaths := []string{
    70  		"knative.+/test/upgrade",
    71  		"knative(:?\\.dev/|-)pkg/test/upgrade/shell",
    72  	}
    73  	for _, validPath := range validPaths {
    74  		r := regexp.MustCompile(validPath)
    75  		if loc := r.FindStringIndex(funcName); loc != nil {
    76  			return nil
    77  		}
    78  	}
    79  	return fmt.Errorf("%w, tried using from: %s",
    80  		ErrCallerNotAllowed, funcName)
    81  }