Specifies the routing information that should be sent along with the request
in the form of routing header.
NOTE: All service configuration rules follow the "last one wins" order.
The examples below will apply to an RPC which has the following request type:
Message Definition:
message Request {
// The name of the Table
// Values can be of the following formats:
// - projects/<project>/tables/<table>
// - projects/<project>/instances/<instance>/tables/<table>
// - region/<region>/zones/<zone>/tables/<table>
string table_name = 1;
// This value specifies routing for replication.
// It can be in the following formats:
// - profiles/<profile_id>
// - a legacy profile_id that can be any string
string app_profile_id = 2;
}
Example message:
{
table_name: projects/proj_foo/instances/instance_bar/table/table_baz,
app_profile_id: profiles/prof_qux
}
The routing header consists of one or multiple key-value pairs. Every key
and value must be percent-encoded, and joined together in the format of
key1=value1&key2=value2.
In the examples below I am skipping the percent-encoding for readablity.
Example 1
Extracting a field from the request to put into the routing header
unchanged, with the key equal to the field name.
annotation:
option (google.api.routing) = {
// Take the app_profile_id.
routing_parameters {
field: "app_profile_id"
}
};
result:
x-goog-request-params: app_profile_id=profiles/prof_qux
Example 2
Extracting a field from the request to put into the routing header
unchanged, with the key different from the field name.
annotation:
option (google.api.routing) = {
// Take the app_profile_id, but name it routing_id in the header.
routing_parameters {
field: "app_profile_id"
path_template: "{routing_id=}"
}
};
result:
x-goog-request-params: routing_id=profiles/prof_qux
Example 3
Extracting a field from the request to put into the routing
header, while matching a path template syntax on the field's value.
NB: it is more useful to send nothing than to send garbage for the purpose
of dynamic routing, since garbage pollutes cache. Thus the matching.
Sub-example 3a
The field matches the template.
annotation:
option (google.api.routing) = {
// Take the table_name, if it's well-formed (with project-based
// syntax).
routing_parameters {
field: "table_name"
path_template: "{table_name=projects/*/instances/*/*}"
}
};
result:
x-goog-request-params:
table_name=projects/proj_foo/instances/instance_bar/table/table_baz
Sub-example 3b
The field does not match the template.
annotation:
option (google.api.routing) = {
// Take the table_name, if it's well-formed (with region-based
// syntax).
routing_parameters {
field: "table_name"
path_template: "{table_name=regions/*/zones/*/*}"
}
};
result:
<no routing header will be sent>
Sub-example 3c
Multiple alternative conflictingly named path templates are
specified. The one that matches is used to construct the header.
annotation:
option (google.api.routing) = {
// Take the table_name, if it's well-formed, whether
// using the region- or projects-based syntax.
routing_parameters {
field: "table_name"
path_template: "{table_name=regions/*/zones/*/*}"
}
routing_parameters {
field: "table_name"
path_template: "{table_name=projects/*/instances/*/*}"
}
};
result:
x-goog-request-params:
table_name=projects/proj_foo/instances/instance_bar/table/table_baz
Example 4
Extracting a single routing header key-value pair by matching a
template syntax on (a part of) a single request field.
annotation:
option (google.api.routing) = {
// Take just the project id from the table_name field.
routing_parameters {
field: "table_name"
path_template: "{routing_id=projects/*}/*"
}
};
result:
x-goog-request-params: routing_id=projects/proj_foo
Example 5
Extracting a single routing header key-value pair by matching
several conflictingly named path templates on (parts of) a single request
field. The last template to match "wins" the conflict.
annotation:
option (google.api.routing) = {
// If the table_name does not have instances information,
// take just the project id for routing.
// Otherwise take project + instance.
routing_parameters {
field: "table_name"
path_template: "{routing_id=projects/*}/*"
}
routing_parameters {
field: "table_name"
path_template: "{routing_id=projects/*/instances/*}/*"
}
};
result:
x-goog-request-params:
routing_id=projects/proj_foo/instances/instance_bar
Example 6
Extracting multiple routing header key-value pairs by matching
several non-conflicting path templates on (parts of) a single request field.
Sub-example 6a
Make the templates strict, so that if the table_name does not
have an instance information, nothing is sent.
annotation:
option (google.api.routing) = {
// The routing code needs two keys instead of one composite
// but works only for the tables with the "project-instance" name
// syntax.
routing_parameters {
field: "table_name"
path_template: "{project_id=projects/*}/instances/*/*"
}
routing_parameters {
field: "table_name"
path_template: "projects/*/{instance_id=instances/*}/*"
}
};
result:
x-goog-request-params:
project_id=projects/proj_foo&instance_id=instances/instance_bar
Sub-example 6b
Make the templates loose, so that if the table_name does not
have an instance information, just the project id part is sent.
annotation:
option (google.api.routing) = {
// The routing code wants two keys instead of one composite
// but will work with just the project_id for tables without
// an instance in the table_name.
routing_parameters {
field: "table_name"
path_template: "{project_id=projects/*}/*"
}
routing_parameters {
field: "table_name"
path_template: "projects/*/{instance_id=instances/*}/*"
}
};
result (is the same as 6a for our example message because it has the instance
information):
x-goog-request-params:
project_id=projects/proj_foo&instance_id=instances/instance_bar
Example 7
Extracting multiple routing header key-value pairs by matching
several path templates on multiple request fields.
NB: note that here there is no way to specify sending nothing if one of the
fields does not match its template. E.g. if the table_name is in the wrong
format, the project_id will not be sent, but the routing_id will be.
The backend routing code has to be aware of that and be prepared to not
receive a full complement of keys if it expects multiple.
annotation:
option (google.api.routing) = {
// The routing needs both project_id and routing_id
// (from the app_profile_id field) for routing.
routing_parameters {
field: "table_name"
path_template: "{project_id=projects/*}/*"
}
routing_parameters {
field: "app_profile_id"
path_template: "{routing_id=}"
}
};
result:
x-goog-request-params:
project_id=projects/proj_foo&routing_id=profiles/prof_qux
Example 8
Extracting a single routing header key-value pair by matching
several conflictingly named path templates on several request fields. The
last template to match "wins" the conflict.
annotation:
option (google.api.routing) = {
// The routing_id can be a project id or a region id depending on
// the table name format, but only if the app_profile_id is not set.
// If app_profile_id is set it should be used instead.
routing_parameters {
field: "table_name"
path_template: "{routing_id=projects/*}/*"
}
routing_parameters {
field: "table_name"
path_template: "{routing_id=regions/*}/*"
}
routing_parameters {
field: "app_profile_id"
path_template: "{routing_id=}"
}
};
result:
x-goog-request-params: routing_id=profiles/prof_qux
Example 9
Bringing it all together.
annotation:
option (google.api.routing) = {
// For routing both table_location and a routing_id are needed.
//
// table_location can be either an instance id or a region+zone id.
//
// For routing_id, take the value of app_profile_id
// - If it's in the format profiles/<profile_id>, send
// just the <profile_id> part.
// - If it's any other literal, send it as is.
// If the app_profile_id is empty, and the table_name starts with
// the project_id, send that instead.
routing_parameters {
field: "table_name"
path_template: "projects/*/{table_location=instances/*}/tables/*"
}
routing_parameters {
field: "table_name"
path_template: "{table_location=regions/*/zones/*}/tables/*"
}
routing_parameters {
field: "table_name"
path_template: "{routing_id=projects/*}/**"
}
routing_parameters {
field: "app_profile_id"
path_template: "{routing_id=}"
}
routing_parameters {
field: "app_profile_id"
path_template: "profiles/{routing_id=*}"
}
};
result:
x-goog-request-params:
table_location=instances/instance_bar&routing_id=prof_qux
Protobuf type google.api.RoutingRule
A collection of Routing Parameter specifications.
NOTE: If multiple Routing Parameters describe the same key
(via the path_template field or via the field field when
path_template is not provided), "last one wins" rule
determines which Parameter gets used.
See the examples for more details.
repeated .google.api.RoutingParameter routing_parameters = 2;
A collection of Routing Parameter specifications.
NOTE: If multiple Routing Parameters describe the same key
(via the path_template field or via the field field when
path_template is not provided), "last one wins" rule
determines which Parameter gets used.
See the examples for more details.
repeated .google.api.RoutingParameter routing_parameters = 2;
A collection of Routing Parameter specifications.
NOTE: If multiple Routing Parameters describe the same key
(via the path_template field or via the field field when
path_template is not provided), "last one wins" rule
determines which Parameter gets used.
See the examples for more details.
repeated .google.api.RoutingParameter routing_parameters = 2;
A collection of Routing Parameter specifications.
NOTE: If multiple Routing Parameters describe the same key
(via the path_template field or via the field field when
path_template is not provided), "last one wins" rule
determines which Parameter gets used.
See the examples for more details.
repeated .google.api.RoutingParameter routing_parameters = 2;
A collection of Routing Parameter specifications.
NOTE: If multiple Routing Parameters describe the same key
(via the path_template field or via the field field when
path_template is not provided), "last one wins" rule
determines which Parameter gets used.
See the examples for more details.
repeated .google.api.RoutingParameter routing_parameters = 2;
