Update MediaType parser to handle parameter without value (#3999) (#4000

) * Update MediaType parser to handle parameter without value. Use consumeTokenIfPresent instead of consumeToken Update consumeTokenIfPresent to return null instead of an empty string when matcher is not matched Add unit test * handle single empty parameter, update test case
helidon-io · Mar 24, 2022 · 853b095 · 853b095
1 parent 85bb1cb
commit 853b095
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Showing 3 changed files with 31 additions and 20 deletions.
diff --git a/common/http/src/main/java/io/helidon/common/http/MediaType.java b/common/http/src/main/java/io/helidon/common/http/MediaType.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, 2021 Oracle and/or its affiliates.
+ * Copyright (c) 2018, 2022 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -325,23 +325,27 @@ public static MediaType parse(String input) {
                 String attribute = tokenizer.consumeToken(TOKEN_MATCHER);
                 tokenizer.consumeCharacter('=');
                 final String value;
-                if ('"' == tokenizer.previewChar()) {
-                    tokenizer.consumeCharacter('"');
-                    StringBuilder valueBuilder = new StringBuilder();
-                    while ('"' != tokenizer.previewChar()) {
-                        if ('\\' == tokenizer.previewChar()) {
-                            tokenizer.consumeCharacter('\\');
-                            valueBuilder.append(tokenizer.consumeCharacter(CharMatcher.ascii()));
-                        } else {
-                            valueBuilder.append(tokenizer.consumeToken(QUOTED_TEXT_MATCHER));
+                if (tokenizer.hasMore()) {
+                    if ('"' == tokenizer.previewChar()) {
+                        tokenizer.consumeCharacter('"');
+                        StringBuilder valueBuilder = new StringBuilder();
+                        while ('"' != tokenizer.previewChar()) {
+                            if ('\\' == tokenizer.previewChar()) {
+                                tokenizer.consumeCharacter('\\');
+                                valueBuilder.append(tokenizer.consumeCharacter(CharMatcher.ascii()));
+                            } else {
+                                valueBuilder.append(tokenizer.consumeToken(QUOTED_TEXT_MATCHER));
+                            }
                         }
+                        value = valueBuilder.toString();
+                        tokenizer.consumeCharacter('"');
+                    } else {
+                        value = tokenizer.consumeTokenIfPresent(TOKEN_MATCHER);
+                    }
+                    if (value != null) {
+                        parameters.put(attribute, value);
                     }
-                    value = valueBuilder.toString();
-                    tokenizer.consumeCharacter('"');
-                } else {
-                    value = tokenizer.consumeToken(TOKEN_MATCHER);
                 }
-                parameters.put(attribute, value);
             }
             return create(type, subtype, parameters);
         } catch (IllegalStateException e) {

diff --git a/common/http/src/main/java/io/helidon/common/http/Tokenizer.java b/common/http/src/main/java/io/helidon/common/http/Tokenizer.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, 2020 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, 2022 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -46,15 +46,16 @@ public Tokenizer(String input) {
      * position the to next character if matched.
      *
      * @param matcher matcher to use
-     * @return token matched
+     * @return token matched, or {@code null} if not matched
      * @throws IllegalStateException if {@link #hasMore() } returns
      * {@code false}
      */
     public String consumeTokenIfPresent(CharMatcher matcher) {
         checkState(hasMore(), "No more elements!");
         int startPosition = position;
         position = matcher.negate().indexIn(input, startPosition);
-        return hasMore() ? input.substring(startPosition, position)
+        return position == startPosition ? null
+                : hasMore() ? input.substring(startPosition, position)
                 : input.substring(startPosition);
     }
 

diff --git a/common/http/src/test/java/io/helidon/common/http/MediaTypeTest.java b/common/http/src/test/java/io/helidon/common/http/MediaTypeTest.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, 2020 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, 2022 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -77,6 +77,12 @@ void parseDuplicateParameters() {
         assertThat(mediaType.parameters(), is(Map.of("option", "value2")));
     }
 
+    @Test
+    void parseEmptyParameterValue() {
+        assertThat(MediaType.parse("type/subtype; o1=").parameters(), is(Map.of()));
+        assertThat(MediaType.parse("type/subtype; o1=; o2=v2").parameters(), is(Map.of("o2", "v2")));
+    }
+
     @Test
     void qualityFactor() {
         MediaType mediaType = MediaType.parse("unknown-type/unknown-subtype; q=0.2");
@@ -127,4 +133,4 @@ void testBuilt() {
         assertThat(mediaType.parameters(), is(Map.of("q", "0.1", "charset", "ISO-8859-2")));
         assertThat(mediaType.qualityFactor(), closeTo(0.1, 0.000001));
     }
-}
+}