// Copyright 2020 The gRPC Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

// Local copy of Envoy xDS proto file, used for testing only.

syntax = "proto3";

package envoy.config.route.v3;

import "src/proto/grpc/testing/xds/v3/base.proto";
import "src/proto/grpc/testing/xds/v3/extension.proto";
import "src/proto/grpc/testing/xds/v3/regex.proto";
import "src/proto/grpc/testing/xds/v3/percent.proto";
import "src/proto/grpc/testing/xds/v3/range.proto";

import "google/protobuf/any.proto";
import "google/protobuf/duration.proto";
import "google/protobuf/wrappers.proto";

// [#protodoc-title: HTTP route components]
// * Routing :ref:`architecture overview <arch_overview_http_routing>`
// * HTTP :ref:`router filter <config_http_filters_router>`

message RetryPolicy {
  string retry_on = 1;
  google.protobuf.UInt32Value num_retries = 2;

  message RetryBackOff {
    google.protobuf.Duration base_interval = 1;
    google.protobuf.Duration max_interval = 2;
  }

  RetryBackOff retry_back_off = 8;
}

// The top level element in the routing configuration is a virtual host. Each virtual host has
// a logical name as well as a set of domains that get routed to it based on the incoming request's
// host header. This allows a single listener to service multiple top level domain path trees. Once
// a virtual host is selected based on the domain, the routes are processed in order to see which
// upstream cluster to route to or whether to perform a redirect.
// [#next-free-field: 21]
message VirtualHost {
  // The logical name of the virtual host. This is used when emitting certain
  // statistics but is not relevant for routing.
  string name = 1;

  // A list of domains (host/authority header) that will be matched to this
  // virtual host. Wildcard hosts are supported in the suffix or prefix form.
  //
  // Domain search order:
  //  1. Exact domain names: ``www.foo.com``.
  //  2. Suffix domain wildcards: ``*.foo.com`` or ``*-bar.foo.com``.
  //  3. Prefix domain wildcards: ``foo.*`` or ``foo-*``.
  //  4. Special wildcard ``*`` matching any domain.
  //
  // .. note::
  //
  //   The wildcard will not match the empty string.
  //   e.g. ``*-bar.foo.com`` will match ``baz-bar.foo.com`` but not ``-bar.foo.com``.
  //   The longest wildcards match first.
  //   Only a single virtual host in the entire route configuration can match on ``*``. A domain
  //   must be unique across all virtual hosts or the config will fail to load.
  //
  // Domains cannot contain control characters. This is validated by the well_known_regex HTTP_HEADER_VALUE.
  repeated string domains = 2;

  // The list of routes that will be matched, in order, for incoming requests.
  // The first route that matches will be used.
  repeated Route routes = 3;

  // The per_filter_config field can be used to provide virtual host-specific
  // configurations for filters. The key should match the filter name, such as
  // *envoy.filters.http.buffer* for the HTTP buffer filter. Use of this field is filter
  // specific; see the :ref:`HTTP filter documentation <config_http_filters>`
  // for if and how it is utilized.
  map<string, google.protobuf.Any> typed_per_filter_config = 15;

  RetryPolicy retry_policy = 16;
}

// A route is both a specification of how to match a request as well as an indication of what to do
// next (e.g., redirect, forward, rewrite, etc.).
//
// .. attention::
//
//   Envoy supports routing on HTTP method via :ref:`header matching
//   <envoy_api_msg_config.route.v3.HeaderMatcher>`.
// [#next-free-field: 18]
message Route {
  // Name for the route.
  string name = 14;

  // Route matching parameters.
  RouteMatch match = 1;

  message NonForwardingAction {
  }  

  oneof action {
    // Route request to some upstream cluster.
    RouteAction route = 2;

    // Return a redirect.
    RedirectAction redirect = 3;

    // An action used when the route will generate a response directly,
    // without forwarding to an upstream host. This will be used in non-proxy
    // xDS clients like the gRPC server. It could also be used in the future
    // in Envoy for a filter that directly generates responses for requests.
    NonForwardingAction non_forwarding_action = 18;
  }

  // The typed_per_filter_config field can be used to provide route-specific
  // configurations for filters. The key should match the filter name, such as
  // *envoy.filters.http.buffer* for the HTTP buffer filter. Use of this field is filter
  // specific; see the :ref:`HTTP filter documentation <config_http_filters>` for
  // if and how it is utilized.
  map<string, google.protobuf.Any> typed_per_filter_config = 13;
}

// Compared to the :ref:`cluster <envoy_api_field_config.route.v3.RouteAction.cluster>` field that specifies a
// single upstream cluster as the target of a request, the :ref:`weighted_clusters
// <envoy_api_field_config.route.v3.RouteAction.weighted_clusters>` option allows for specification of
// multiple upstream clusters along with weights that indicate the percentage of
// traffic to be forwarded to each cluster. The router selects an upstream cluster based on the
// weights.
message WeightedCluster {
  // [#next-free-field: 11]
  message ClusterWeight {
    // Name of the upstream cluster. The cluster must exist in the
    // :ref:`cluster manager configuration <config_cluster_manager>`.
    string name = 1;

    // An integer between 0 and :ref:`total_weight
    // <envoy_api_field_config.route.v3.WeightedCluster.total_weight>`. When a request matches the route,
    // the choice of an upstream cluster is determined by its weight. The sum of weights across all
    // entries in the clusters array must add up to the total_weight, which defaults to 100.
    google.protobuf.UInt32Value weight = 2;

    // The per_filter_config field can be used to provide weighted cluster-specific
    // configurations for filters. The key should match the filter name, such as
    // *envoy.filters.http.buffer* for the HTTP buffer filter. Use of this field is filter
    // specific; see the :ref:`HTTP filter documentation <config_http_filters>`
    // for if and how it is utilized.
    map<string, google.protobuf.Any> typed_per_filter_config = 10;
  }

  // Specifies one or more upstream clusters associated with the route.
  repeated ClusterWeight clusters = 1;

  // Specifies the total weight across all clusters. The sum of all cluster weights must equal this
  // value, which must be greater than 0. Defaults to 100.
  google.protobuf.UInt32Value total_weight = 3;
}

// [#next-free-field: 13]
message RouteMatch {
  oneof path_specifier {
    // If specified, the route is a prefix rule meaning that the prefix must
    // match the beginning of the *:path* header.
    string prefix = 1;

    // If specified, the route is an exact path rule meaning that the path must
    // exactly match the *:path* header once the query string is removed.
    string path = 2;

    // If specified, the route is a regular expression rule meaning that the
    // regex must match the *:path* header once the query string is removed. The entire path
    // (without the query string) must match the regex. The rule will not match if only a
    // subsequence of the *:path* header matches the regex.
    //
    // [#next-major-version: In the v3 API we should redo how path specification works such
    // that we utilize StringMatcher, and additionally have consistent options around whether we
    // strip query strings, do a case sensitive match, etc. In the interim it will be too disruptive
    // to deprecate the existing options. We should even consider whether we want to do away with
    // path_specifier entirely and just rely on a set of header matchers which can already match
    // on :path, etc. The issue with that is it is unclear how to generically deal with query string
    // stripping. This needs more thought.]
    type.matcher.v3.RegexMatcher safe_regex = 10;
  }

  // Indicates that prefix/path matching should be case insensitive. The default
  // is true.
  google.protobuf.BoolValue case_sensitive = 4;

  // Indicates that the route should additionally match on a runtime key. Every time the route
  // is considered for a match, it must also fall under the percentage of matches indicated by
  // this field. For some fraction N/D, a random number in the range [0,D) is selected. If the
  // number is <= the value of the numerator N, or if the key is not present, the default
  // value, the router continues to evaluate the remaining match criteria. A runtime_fraction
  // route configuration can be used to roll out route changes in a gradual manner without full
  // code/config deploys. Refer to the :ref:`traffic shifting
  // <config_http_conn_man_route_table_traffic_splitting_shift>` docs for additional documentation.
  //
  // .. note::
  //
  //    Parsing this field is implemented such that the runtime key's data may be represented
  //    as a FractionalPercent proto represented as JSON/YAML and may also be represented as an
  //    integer with the assumption that the value is an integral percentage out of 100. For
  //    instance, a runtime key lookup returning the value "42" would parse as a FractionalPercent
  //    whose numerator is 42 and denominator is HUNDRED. This preserves legacy semantics.
  core.v3.RuntimeFractionalPercent runtime_fraction = 9;

  // Specifies a set of headers that the route should match on. The router will
  // check the request’s headers against all the specified headers in the route
  // config. A match will happen if all the headers in the route are present in
  // the request with the same values (or based on presence if the value field
  // is not in the config).
  repeated HeaderMatcher headers = 6;

  // Specifies a set of URL query parameters on which the route should
  // match. The router will check the query string from the *path* header
  // against all the specified query parameters. If the number of specified
  // query parameters is nonzero, they all must match the *path* header's
  // query string for a match to occur.
  repeated QueryParameterMatcher query_parameters = 7;
}

message MaxStreamDuration {
  // Specifies the maximum duration allowed for streams on the route. If not specified, the value
  // from the :ref:`max_stream_duration
  // <envoy_api_field_config.core.v3.HttpProtocolOptions.max_stream_duration>` field in
  // :ref:`HttpConnectionManager.common_http_protocol_options
  // <envoy_api_field_extensions.filters.network.http_connection_manager.v3.HttpConnectionManager.common_http_protocol_options>`
  // is used. If this field is set explicitly to zero, any
  // HttpConnectionManager max_stream_duration timeout will be disabled for
  // this route.
  google.protobuf.Duration max_stream_duration = 1;

  // If present, and the request contains a `grpc-timeout header
  // <https://github.com/grpc/grpc/blob/master/doc/PROTOCOL-HTTP2.md>`_, use that value as the
  // *max_stream_duration*, but limit the applied timeout to the maximum value specified here.
  // If set to 0, the `grpc-timeout` header is used without modification.
  google.protobuf.Duration grpc_timeout_header_max = 2;
}

// [#next-free-field: 37]
message RouteAction {
  oneof cluster_specifier {
    // Indicates the upstream cluster to which the request should be routed
    // to.
    string cluster = 1;

    // Envoy will determine the cluster to route to by reading the value of the
    // HTTP header named by cluster_header from the request headers. If the
    // header is not found or the referenced cluster does not exist, Envoy will
    // return a 404 response.
    //
    // .. attention::
    //
    //   Internally, Envoy always uses the HTTP/2 *:authority* header to represent the HTTP/1
    //   *Host* header. Thus, if attempting to match on *Host*, match on *:authority* instead.
    string cluster_header = 2;

    // Multiple upstream clusters can be specified for a given route. The
    // request is routed to one of the upstream clusters based on weights
    // assigned to each cluster. See
    // :ref:`traffic splitting <config_http_conn_man_route_table_traffic_splitting_split>`
    // for additional documentation.
    WeightedCluster weighted_clusters = 3;

    // Name of the cluster specifier plugin to use to determine the cluster for
    // requests on this route. The plugin name must be defined in the associated
    // :ref:`envoy_v3_api_field_config.route.v3.RouteConfiguration.cluster_specifier_plugins`
    // in the
    // :ref:`envoy_v3_api_field_config.core.v3.TypedExtensionConfig.name` field.
    string cluster_specifier_plugin = 37;
  }

  message HashPolicy {
    message Header {
      // The name of the request header that will be used to obtain the hash
      // key. If the request header is not present, no hash will be produced.
      string header_name = 1;

      // If specified, the request header value will be rewritten and used
      // to produce the hash key.
      type.matcher.v3.RegexMatchAndSubstitute regex_rewrite = 2;
    }
    
    message Cookie {
      string name = 1;
    }

    message ConnectionProperties {
      bool source_ip = 1;
    }

    message QueryParameter {
      string name = 1;
    }

    message FilterState {
      // The name of the Object in the per-request filterState, which is an
      // Envoy::Http::Hashable object. If there is no data associated with the key,
      // or the stored object is not Envoy::Http::Hashable, no hash will be produced.
      string key = 1;
    }

    oneof policy_specifier {
      // Header hash policy.
      Header header = 1;

      // Cookie hash policy.
      Cookie cookie = 2;

      // Connection properties hash policy.
      ConnectionProperties connection_properties = 3;

      // Query parameter hash policy.
      QueryParameter query_parameter = 5;

      // Filter state hash policy.
      FilterState filter_state = 6;
    }

    // The flag that short-circuits the hash computing. This field provides a
    // 'fallback' style of configuration: "if a terminal policy doesn't work,
    // fallback to rest of the policy list", it saves time when the terminal
    // policy works.
    //
    // If true, and there is already a hash computed, ignore rest of the
    // list of hash polices.
    // For example, if the following hash methods are configured:
    //
    //  ========= ========
    //  specifier terminal
    //  ========= ========
    //  Header A  true
    //  Header B  false
    //  Header C  false
    //  ========= ========
    //
    // The generateHash process ends if policy "header A" generates a hash, as
    // it's a terminal policy.
    bool terminal = 4;
  }

  repeated HashPolicy hash_policy = 15;

  RetryPolicy retry_policy = 9;

  // Specifies the maximum stream duration for this route.
  MaxStreamDuration max_stream_duration = 36;
}

// .. attention::
//
//   Internally, Envoy always uses the HTTP/2 *:authority* header to represent the HTTP/1 *Host*
//   header. Thus, if attempting to match on *Host*, match on *:authority* instead.
//
// .. attention::
//
//   To route on HTTP method, use the special HTTP/2 *:method* header. This works for both
//   HTTP/1 and HTTP/2 as Envoy normalizes headers. E.g.,
//
//   .. code-block:: json
//
//     {
//       "name": ":method",
//       "exact_match": "POST"
//     }
//
// .. attention::
//   In the absence of any header match specifier, match will default to :ref:`present_match
//   <envoy_api_field_config.route.v3.HeaderMatcher.present_match>`. i.e, a request that has the :ref:`name
//   <envoy_api_field_config.route.v3.HeaderMatcher.name>` header will match, regardless of the header's
//   value.
//
//  [#next-major-version: HeaderMatcher should be refactored to use StringMatcher.]
// [#next-free-field: 12]
message HeaderMatcher {
  // Specifies the name of the header in the request.
  string name = 1;

  // Specifies how the header match will be performed to route the request.
  oneof header_match_specifier {
    // If specified, header match will be performed based on the value of the header.
    string exact_match = 4;

    // If specified, this regex string is a regular expression rule which implies the entire request
    // header value must match the regex. The rule will not match if only a subsequence of the
    // request header value matches the regex.
    type.matcher.v3.RegexMatcher safe_regex_match = 11;

    // If specified, header match will be performed based on range.
    // The rule will match if the request header value is within this range.
    // The entire request header value must represent an integer in base 10 notation: consisting of
    // an optional plus or minus sign followed by a sequence of digits. The rule will not match if
    // the header value does not represent an integer. Match will fail for empty values, floating
    // point numbers or if only a subsequence of the header value is an integer.
    //
    // Examples:
    //
    // * For range [-10,0), route will match for header value -1, but not for 0, "somestring", 10.9,
    //   "-1somestring"
    type.v3.Int64Range range_match = 6;

    // If specified, header match will be performed based on whether the header is in the
    // request.
    bool present_match = 7;

    // If specified, header match will be performed based on the prefix of the header value.
    // Note: empty prefix is not allowed, please use present_match instead.
    //
    // Examples:
    //
    // * The prefix *abcd* matches the value *abcdxyz*, but not for *abcxyz*.
    string prefix_match = 9;

    // If specified, header match will be performed based on the suffix of the header value.
    // Note: empty suffix is not allowed, please use present_match instead.
    //
    // Examples:
    //
    // * The suffix *abcd* matches the value *xyzabcd*, but not for *xyzbcd*.
    string suffix_match = 10;
  }

  // If specified, the match result will be inverted before checking. Defaults to false.
  //
  // Examples:
  //
  // * The regex ``\d{3}`` does not match the value *1234*, so it will match when inverted.
  // * The range [-10,0) will match the value -1, so it will not match when inverted.
  bool invert_match = 8;
}

// Query parameter matching treats the query string of a request's :path header
// as an ampersand-separated list of keys and/or key=value elements.
// [#next-free-field: 7]
message QueryParameterMatcher {
}

// Configuration for a cluster specifier plugin.
message ClusterSpecifierPlugin {
  // The name of the plugin and its opaque configuration.
  core.v3.TypedExtensionConfig extension = 1;

  // If is_optional is not set and the plugin defined by this message is not
  // a supported type, the containing resource is NACKed. If is_optional is
  // set, the resource would not be NACKed for this reason. In this case,
  // routes referencing this plugin's name would not be treated as an illegal
  // configuration, but would result in a failure if the route is selected.
  bool is_optional = 2;
}

// [#protodoc-title: HTTP route configuration]
// * Routing :ref:`architecture overview <arch_overview_http_routing>`
// * HTTP :ref:`router filter <config_http_filters_router>`

// [#next-free-field: 11]
message RouteConfiguration {
  // The name of the route configuration. For example, it might match
  // :ref:`route_config_name
  // <envoy_api_field_extensions.filters.network.http_connection_manager.v3.Rds.route_config_name>` in
  // :ref:`envoy_api_msg_extensions.filters.network.http_connection_manager.v3.Rds`.
  string name = 1;

  // An array of virtual hosts that make up the route table.
  repeated VirtualHost virtual_hosts = 2;

  // A list of plugins and their configurations which may be used by a
  // :ref:`envoy_v3_api_field_config.route.v3.RouteAction.cluster_specifier_plugin`
  // within the route. All *extension.name* fields in this list must be unique.
  repeated ClusterSpecifierPlugin cluster_specifier_plugins = 12;
}

message RedirectAction {
}

message FilterConfig {
  // The filter config.
  google.protobuf.Any config = 1;

  // If true, the filter is optional, meaning that if the client does
  // not support the specified filter, it may ignore the map entry rather
  // than rejecting the config.
  bool is_optional = 2;
}
