1 /*
2 * Copyright (c) 2002-2022, City of Paris
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright notice
10 * and the following disclaimer.
11 *
12 * 2. Redistributions in binary form must reproduce the above copyright notice
13 * and the following disclaimer in the documentation and/or other materials
14 * provided with the distribution.
15 *
16 * 3. Neither the name of 'Mairie de Paris' nor 'Lutece' nor the names of its
17 * contributors may be used to endorse or promote products derived from
18 * this software without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
21 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
24 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30 * POSSIBILITY OF SUCH DAMAGE.
31 *
32 * License 1.0
33 */
34 package fr.paris.lutece.util.env;
35
36 import java.io.IOException;
37 import java.nio.file.Files;
38 import java.nio.file.Paths;
39 import java.util.Map;
40 import java.util.regex.Matcher;
41 import java.util.regex.Pattern;
42
43 /**
44 * EnvUtil
45 */
46 public final class EnvUtil
47 {
48 public static final String PREFIX_ENV = "env.";
49 private static final String SUFFIX_FILE = "_FILE";
50 private static final String PATTERN_MARKER = "\\$\\{(.+?)\\}";
51
52 private static Pattern _pattern = Pattern.compile( PATTERN_MARKER );
53
54 private static Map<String, String> _mapEnv = System.getenv( );
55
56 // Private constructor
57 private EnvUtil( )
58 {
59 }
60
61 /**
62 * Evaluate a string that may contain a reference to an environement variable enclosed by ${...}
63 *
64 * @param strSource
65 * The source string
66 * @return The source string or the env variable's value if found.
67 */
68 public static String evaluate( String strSource )
69 {
70 return evaluate( strSource, "" );
71 }
72
73 /**
74 * Evaluate a string that may contain a reference to an environement variable enclosed by ${...}. If the environement variable has a suffix _FILE the
75 * evaluation will take the content of the file as value.
76 *
77 * @param strSource
78 * The source string
79 * @param strEnvPrefix
80 * A prefix of the environment
81 * @return The source string or the env variable's value if found.
82 */
83 public static String evaluate( String strSource, String strEnvPrefix )
84 {
85 String strOutput = ( strSource != null ) ? strSource : "";
86 Matcher matcher = _pattern.matcher( strOutput );
87 int offset = 0;
88
89 while ( matcher.find( ) )
90 {
91 String strMarker = matcher.group( );
92 String strEnvVariable = strMarker.substring( 2 + strEnvPrefix.length( ), strMarker.length( ) - 1 );
93 String strValue = _mapEnv.get( strEnvVariable );
94 if ( strEnvVariable.endsWith( SUFFIX_FILE ) )
95 {
96 strValue = getFileContent( strValue );
97 }
98 strValue = strValue == null ? "" : strValue;
99 strOutput = strOutput.substring( 0, matcher.start( ) + offset ) + strValue + strOutput.substring( matcher.end( ) + offset );
100 offset += strValue.length( ) - strMarker.length( );
101 }
102 return strOutput;
103 }
104
105 /**
106 * Mock Env map for unit testing
107 *
108 * @param mapEnv
109 * a mock map
110 */
111 static void setMockMapEnv( Map<String, String> mapEnv )
112 {
113 _mapEnv = mapEnv;
114 }
115
116 /**
117 * Gets the content of a file as a String
118 *
119 * @param strFilePath
120 * The file path
121 * @return The file content or the error message while reading the message
122 */
123 private static String getFileContent( String strFilePath )
124 {
125 String strData;
126 try
127 {
128 strData = new String( Files.readAllBytes( Paths.get( strFilePath ) ) );
129 }
130 catch( IOException e )
131 {
132 return e.getMessage( );
133 }
134 return strData;
135 }
136
137 }