Line data    Source code

       1             : #pragma once
       2             : 
       3             : #include <ostream>
       4             : #include <string>
       5             : 
       6             : #include "source/extensions/path/uri_template_lib/uri_template_internal.h"
       7             : 
       8             : #include "absl/status/statusor.h"
       9             : #include "absl/strings/string_view.h"
      10             : 
      11             : namespace Envoy {
      12             : namespace Extensions {
      13             : namespace UriTemplate {
      14             : 
      15             : // This library provides functionality to rewrite paths based on templates
      16             : // (https://www.rfc-editor.org/rfc/rfc6570.html). Paths are matches against "match patterns" which
      17             : // capture matched tokens. For example: The match pattern "/foo/{bar}" will match "/foo/cat" and
      18             : // will capture "cat" in the variable "bar".
      19             : //
      20             : // A matched path can then be rewritten with a rewrite pattern.
      21             : // For example: rewrite pattern "/pat/hat/{bar}" would use the captured variable "bar" from above
      22             : // to rewrite "/foo/cat" into "/pat/hat/cat"
      23             : 
      24             : enum class RewriteStringKind { Variable, Literal };
      25             : 
      26             : struct ParsedSegment {
      27        1163 :   ParsedSegment(absl::string_view value, RewriteStringKind kind) : value_(value), kind_(kind) {}
      28             :   absl::string_view value_;
      29             :   RewriteStringKind kind_;
      30             : 
      31             :   friend std::ostream& operator<<(std::ostream& os, const ParsedSegment& parsed_segment);
      32             : };
      33             : 
      34             : // Stores string literals and regex capture indexes for rewriting paths
      35             : using RewriteSegment = absl::variant<int, std::string>;
      36             : 
      37             : // Stores all segments in left to right order for a path rewrite
      38             : using RewriteSegments = std::vector<RewriteSegment>;
      39             : 
      40             : /**
      41             :  * Returns the safe regex that Envoy understands that is equivalent to the given pattern.
      42             :  */
      43             : absl::StatusOr<std::string> convertPathPatternSyntaxToRegex(absl::string_view path_pattern);
      44             : 
      45             : /**
      46             :  * Parses the specified pattern into a sequence of segments (which are
      47             :  * either literals or variable names).
      48             :  **/
      49             : absl::StatusOr<std::vector<ParsedSegment>> parseRewritePattern(absl::string_view path_pattern);
      50             : 
      51             : /**
      52             :  * Returns the parsed path rewrite pattern and processes variables.
      53             :  */
      54             : absl::StatusOr<RewriteSegments> parseRewritePattern(absl::string_view pattern,
      55             :                                                     absl::string_view capture_regex);
      56             : 
      57             : /**
      58             :  * Returns true if provided rewrite pattern is valid.
      59             :  */
      60             : absl::Status isValidRewritePattern(absl::string_view path_template_rewrite);
      61             : 
      62             : /**
      63             :  * Returns true if path_template_rewrite and capture_regex have valid variables.
      64             :  * Every variable in rewrite MUST be present in match.
      65             :  * For example:
      66             :  * Match: /foo/{bar}/{var} and Rewrite: /goo/{var} is valid.
      67             :  * Match: /foo/{bar} and Rewrite: /goo/{bar}/{var} is invalid. Match is missing {var}.
      68             :  */
      69             : absl::Status isValidSharedVariableSet(absl::string_view pattern, absl::string_view capture_regex);
      70             : 
      71             : /**
      72             :  * Returns true if the match_pattern is valid.
      73             :  * Validation attempts to parse pattern into literals and variables.
      74             :  */
      75             : absl::Status isValidMatchPattern(absl::string_view match_pattern);
      76             : 
      77             : } // namespace UriTemplate
      78             : } // namespace Extensions
      79             : } // namespace Envoy