#include "source/extensions/tracers/xray/util.h"

#include "absl/strings/ascii.h"

namespace Envoy {

namespace Extensions {

namespace Tracers {

namespace XRay {

// AWS X-Ray has two sources of sampling rules (wildcard patterns):

//

// 1- The manifest file (static config)

// 2- The X-Ray Service - periodically polled for new rules. (dynamic config)

//

// X-Ray will inspect every single request and try to match it against the set of rules it has to

// decide whether or not a given request should be sampled. That means this wildcard matching

// routine is on the hot path. I've spent a great deal of time to make this function optimal and not

// allocate.

// Using regex matching here has many downsides and it would require us to:

// 1- escape/lint the user input pattern to avoid messing up its meaning (think '.' character is a

// valid regex and URL character) 2- compile the regex and store it with every corresponding part of

// the rule

//

// Those two steps would add significant overhead to the tracer. Meanwhile, the following function

// has a comprehensive test suite and fuzz tests.

  // Check the special case of a single * pattern, as it's common.

} // namespace XRay

} // namespace Tracers

} // namespace Extensions

} // namespace Envoy