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This is documentation for the next version of Tempo. For the latest stable release, go to the latest version.

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Tempo HTTP API

Tempo exposes an API for pushing and querying traces, and operating the cluster itself.

For the sake of clarity, API endpoints are grouped by service. These endpoints are exposed both when running Tempo in microservices and monolithic mode:

  • microservices: each service exposes its own endpoints
  • monolithic: the Tempo process exposes all API endpoints for the services running internally

For externally supported GRPC API, see below.

Endpoints

APIServiceTypeEndpoint
Readiness probeAll servicesHTTPGET /ready
MetricsAll servicesHTTPGET /metrics
PprofAll servicesHTTPGET /debug/pprof
Ingest tracesDistributor-See section for details
Querying traces by idQuery-frontendHTTPGET /api/traces/<traceID>
Searching tracesQuery-frontendHTTPGET /api/search?<params>
Search tag namesQuery-frontendHTTPGET /api/search/tags
Search tag names V2Query-frontendHTTPGET /api/v2/search/tags
Search tag valuesQuery-frontendHTTPGET /api/search/tag/<tag>/values
Search tag values V2Query-frontendHTTPGET /api/v2/search/tag/<tag>/values
TraceQL MetricsQuery-frontendHTTPGET /api/metrics/query_range
TraceQL Metrics (instant)Query-frontendHTTPGET /api/metrics/query
Query Echo EndpointQuery-frontendHTTPGET /api/echo
Overrides APIQuery-frontendHTTPGET,POST,PATCH,DELETE /api/overrides
MemberlistDistributor, Ingester, Querier, CompactorHTTPGET /memberlist
FlushIngesterHTTPGET,POST /flush
ShutdownIngesterHTTPGET,POST /shutdown
Usage MetricsDistributorHTTPGET /usage_metrics
Distributor ring status (*)DistributorHTTPGET /distributor/ring
Ingesters ring statusDistributor, QuerierHTTPGET /ingester/ring
Metrics-generator ring status (*)DistributorHTTPGET /metrics-generator/ring
Compactor ring statusCompactorHTTPGET /compactor/ring
StatusStatusHTTPGET /status
List build informationStatusHTTPGET /api/status/buildinfo

(*) This endpoint isn’t always available, check the specific section for more details.

Readiness probe

GET /ready

Returns status code 200 when Tempo is ready to serve traffic.

Metrics

GET /metrics

Returns the metrics for the running Tempo service in the Prometheus exposition format.

Pprof

GET /debug/pprof/heap
GET /debug/pprof/block
GET /debug/pprof/profile
GET /debug/pprof/trace
GET /debug/pprof/goroutine
GET /debug/pprof/mutex

Returns the runtime profiling data in the format expected by the pprof visualization tool. There are many things which can be profiled using this including heap, trace, goroutine, etc.

For more information, please check out the official documentation of pprof.

Ingest

The Tempo distributor uses the OpenTelemetry Collector receivers as a foundation to ingest trace data. These APIs are meant to be consumed by the corresponding client SDK or pipeline component, such as Grafana Agent, OpenTelemetry Collector, or Jaeger Agent.

ProtocolTypeDocs
OpenTelemetryGRPCLink
OpenTelemetryHTTPLink
JaegerThrift CompactLink
JaegerThrift BinaryLink
JaegerThrift HTTPLink
JaegerGRPCLink
ZipkinHTTPLink

For information on how to use the Zipkin endpoint with curl (for debugging purposes), refer to Pushing spans with HTTP.

Query

The following request is used to retrieve a trace from the query frontend service in a microservices deployment or the Tempo endpoint in a monolithic mode deployment.

GET /api/traces/<traceid>?start=<start>&end=<end>

Parameters:

  • start = (unix epoch seconds) Optional. Along with end define a time range from which traces should be returned.
  • end = (unix epoch seconds) Optional. Along with start define a time range from which traces should be returned. Providing both start and end includes traces for the specified time range only. If the parameters aren’t provided then Tempo checks for the trace across all blocks in backend. If the parameters are provided, it only checks in the blocks within the specified time range, this can result in trace not being found or partial results if it doesn’t fall in the specified time range.

The following query API is also provided on the querier service for debugging purposes.

GET /querier/api/traces/<traceid>?mode=xxxx&blockStart=0000&blockEnd=FFFF&start=<start>&end=<end>

Parameters:

  • mode = (blocks|ingesters|all) Specifies whether the querier should look for the trace in blocks, ingesters or both (all). Default = all
  • blockStart = (GUID) Specifies the blockID start boundary. If specified, the querier only searches blocks with IDs > blockStart. Default = 00000000-0000-0000-0000-000000000000 Example: blockStart=12345678-0000-0000-1235-000001240000
  • blockEnd = (GUID) Specifies the blockID finish boundary. If specified, the querier only searches blocks with IDs < blockEnd. Default = FFFFFFFF-FFFF-FFFF-FFFF-FFFFFFFFFFFF Example: blockStart=FFFFFFFF-FFFF-FFFF-FFFF-456787652341
  • start = (unix epoch seconds) Optional. Along with end define a time range from which traces should be returned.
  • end = (unix epoch seconds) Optional. Along with start define a time range from which traces should be returned. Providing both start and end includes blocks for the specified time range only.

This API isn’t meant to be used directly unless for debugging the sharding functionality of the query frontend.

Returns

By default, this endpoint returns a mostly compatible OpenTelemetry JSON, but if it can also send OpenTelemetry proto if Accept: application/protobuf is passed.

Query V2

The following request is used to retrieve a trace from the query frontend service in a microservices deployment or the Tempo endpoint in a monolithic mode deployment.

GET /api/v2/traces/<traceid>?start=<start>&end=<end>

Parameters:

  • start = (unix epoch seconds) Optional. Along with end define a time range from which traces should be returned.
  • end = (unix epoch seconds) Optional. Along with start define a time range from which traces should be returned. Providing both start and end includes traces for the specified time range only. If the parameters aren’t provided then Tempo checks for the trace across all blocks in backend. If the parameters are provided, it only checks in the blocks within the specified time range, this can result in trace not being found or partial results if it doesn’t fall in the specified time range.

The following query API is also provided on the querier service for debugging purposes.

GET /querier/api/v2/traces/<traceid>?mode=xxxx&blockStart=0000&blockEnd=FFFF&start=<start>&end=<end>

Parameters:

  • mode = (blocks|ingesters|all) Specifies whether the querier should look for the trace in blocks, ingesters or both (all). Default = all
  • blockStart = (GUID) Specifies the blockID start boundary. If specified, the querier only searches blocks with IDs > blockStart. Default = 00000000-0000-0000-0000-000000000000 Example: blockStart=12345678-0000-0000-1235-000001240000
  • blockEnd = (GUID) Specifies the blockID finish boundary. If specified, the querier only searches blocks with IDs < blockEnd. Default = FFFFFFFF-FFFF-FFFF-FFFF-FFFFFFFFFFFF Example: blockStart=FFFFFFFF-FFFF-FFFF-FFFF-456787652341
  • start = (unix epoch seconds) Optional. Along with end define a time range from which traces should be returned.
  • end = (unix epoch seconds) Optional. Along with start define a time range from which traces should be returned. Providing both start and end includes blocks for the specified time range only.

Returns

By default, this endpoint returns Query response with a OpenTelemetry JSON trace, but if it can also send OpenTelemetry proto if Accept: application/protobuf is passed.

The Tempo Search API finds traces based on span and process attributes (tags and values). Note that search functionality is not available on v2 blocks.

When performing a search, Tempo does a massively parallel search over the given time range, and takes the first N results. Even identical searches differs due to things like machine load and network latency. TraceQL follows the same behavior.

The API is available in the query frontend service in a microservices deployment, or the Tempo endpoint in a monolithic mode deployment.

The following request is used to find traces containing spans from service myservice and the URL contains api/myapi.

GET /api/search?tags=service.name%3Dmyservice%20http.url%3Dapi%2Fmyapi

The URL query parameters support the following values:

Parameters for TraceQL Search

Parameters for Tag Based Search

  • tags = (logfmt): logfmt encoding of any span-level or process-level attributes to filter on. The value is matched as a case-insensitive substring. Key-value pairs are separated by spaces. If a value contains a space, it should be enclosed within double quotes.
  • minDuration = (go duration value) Optional. Find traces with at least this duration. Duration values are of the form 10s for 10 seconds, 100ms, 30m, etc.
  • maxDuration = (go duration value) Optional. Find traces with no greater than this duration. Uses the same form as minDuration.

Parameters supported for all searches

  • limit = (integer) Optional. Limit the number of search results. Default is 20, but this is configurable in the querier. Refer to Configuration.
  • start = (unix epoch seconds) Optional. Along with end define a time range from which traces should be returned.
  • end = (unix epoch seconds) Optional. Along with start, define a time range from which traces should be returned. Providing both start and end changes the way that Tempo searches. If the parameters aren’t provided, then Tempo searches the recent trace data stored in the ingesters. If the parameters are provided, it searches the backend as well.
  • spss = (integer) Optional. Limit the number of spans per span-set. Default value is 3.

Example of how to query Tempo using curl. This query returns all traces that have their status set to error.

bash
$ curl -G -s http://localhost:3200/api/search --data-urlencode 'q={ status=error }' | jq
{
  "traces": [
    {
      "traceID": "2f3e0cee77ae5dc9c17ade3689eb2e54",
      "rootServiceName": "shop-backend",
      "rootTraceName": "update-billing",
      "startTimeUnixNano": "1684778327699392724",
      "durationMs": 557,
      "spanSets": [
        {
          "spans": [
            {
              "spanID": "563d623c76514f8e",
              "startTimeUnixNano": "1684778327735077898",
              "durationNanos": "446979497",
              "attributes": [
                {
                  "key": "status",
                  "value": {
                    "stringValue": "error"
                  }
                }
              ]
            }
          ],
          "matched": 1
        }
      ]
  ],
  "metrics": {
    "totalBlocks": 13
  }
}

Example of how to query Tempo using curl. This query returns all traces that have a tag service.name containing cartservice and a minimum duration of 600 ms.

bash
$ curl -G -s http://localhost:3200/api/search --data-urlencode 'tags=service.name=cartservice' --data-urlencode minDuration=600ms | jq
{
  "traces": [
    {
      "traceID": "d6e9329d67b6146a",
      "rootServiceName": "frontend",
      "rootTraceName": "/cart",
      "startTimeUnixNano": "1634727903545000000",
      "durationMs": 611
    },
    {
      "traceID": "1b1ba462b409200d",
      "rootServiceName": "frontend",
      "rootTraceName": "/cart",
      "startTimeUnixNano": "1634727775935000000",
      "durationMs": 611
    }
  ],
  "metrics": {
    "inspectedTraces": 3100,
    "inspectedBytes": "3811736",
    "totalBlocks": 3
  }
}

Search tags

Ingester configuration complete_block_timeout affects how long tags are available for search.

This endpoint retrieves all discovered tag names that can be used in search. The endpoint is available in the query frontend service in a microservices deployment, or the Tempo endpoint in a monolithic mode deployment. The tags endpoint takes a scope that controls the kinds of tags or attributes returned. If nothing is provided, the endpoint returns all resource and span tags.

GET /api/search/tags?scope=<resource|span|intrinsic>

Example

Example of how to query Tempo using curl. This query returns all discovered tag names.

bash
$ curl -G -s http://localhost:3200/api/search/tags?scope=span  | jq
{
  "tagNames": [
    "host.name",
    "http.method",
    "http.status_code",
    "http.url",
    "ip",
    "load_generator.seq_num",
    "name",
    "region",
    "root_cause_error",
    "sampler.param",
    "sampler.type",
    "service.name",
    "starter",
    "version"
  ]
  "metrics": {
    "inspectedBytes": "630188"
  }
}

Parameters:

  • scope = (resource|span|intrinsic) Optional. Specifies the scope of the tags. If not specified, it means all scopes. Default = all
  • start = (unix epoch seconds) Optional. Along with end, defines a time range from which tags should be returned.
  • end = (unix epoch seconds) Optional. Along with start, defines a time range from which tags should be returned. Providing both start and end includes blocks for the specified time range only.

Search tags V2

Ingester configuration complete_block_timeout affects how long tags are available for search.If start or end aren’t specified, it only fetches blocks that wasn’t flushed to backend.

This endpoint retrieves all discovered tag names that can be used in search. The endpoint is available in the query frontend service in a microservices deployment, or the Tempo endpoint in a monolithic mode deployment. The tags endpoint takes a scope that controls the kinds of tags or attributes returned. If nothing is provided, the endpoint returns all resource and span tags.

bash
GET /api/v2/search/tags?scope=<resource|span|intrinsic>

Parameters:

  • scope = (resource|span|intrinsic) Specifies the scope of the tags, this is an optional parameter, if not specified it means all scopes. Default = all
  • q = (traceql query) Optional. A TraceQL query to filter tag names by. Currently only works for a single spanset of &&ed conditions. For example: { span.foo = "bar" && resource.baz = "bat" ...}. See also Filtered tag values.
  • start = (unix epoch seconds) Optional. Along with end define a time range from which tags should be returned.
  • end = (unix epoch seconds) Optional. Along with start define a time range from which tags should be returned. Providing both start and end includes blocks for the specified time range only.

Example

Example of how to query Tempo using curl. This query returns all discovered tag names.

bash
$ curl -G -s http://localhost:3200/api/v2/search/tags  | jq
{
  "scopes": [
    {
      "name": "link",
      "tags": [
        "link-type"
      ]
    },
    {
      "name": "resource",
      "tags": [
        "k6",
        "service.name"
      ]
    },
    {
      "name": "span",
      "tags": [
        "article.count",
        "http.flavor",
        "http.method",
        "http.request.header.accept",
        "http.request_content_length",
        "http.response.header.content-type",
        "http.response_content_length",
        "http.scheme",
        "http.status_code",
        "http.target",
        "http.url",
        "net.host.name",
        "net.host.port",
        "net.peer.name",
        "net.peer.port",
        "net.sock.family",
        "net.sock.host.addr",
        "net.sock.peer.addr",
        "net.transport",
        "numbers",
        "one"
      ]
    },
    {
      "name": "intrinsic",
      "tags": [
        "duration",
        "event:name",
        "event:timeSinceStart",
        "instrumentation:name",
        "instrumentation:version",
        "kind",
        "name",
        "rootName",
        "rootServiceName",
        "span:duration",
        "span:kind",
        "span:name",
        "span:status",
        "span:statusMessage",
        "status",
        "statusMessage",
        "trace:duration",
        "trace:rootName",
        "trace:rootService",
        "traceDuration"
      ]
    },
    {
      "name": "event",
      "tags": [
        "exception.escape",
        "exception.message",
        "exception.stacktrace",
        "exception.type",
      ]
    }
  ],
  "metrics": {
    "inspectedBytes": "377046"
  }
}

Search tag values

Ingester configuration complete_block_timeout affects how long tags are available for search. If start or end aren’t specified, it only fetches blocks that wasn’t flushed to backend.

This endpoint retrieves all discovered values for the given tag, which can be used in search. The endpoint is available in the query frontend service in a microservices deployment, or the Tempo endpoint in a monolithic mode deployment. The following request returns all discovered service names.

bash
GET /api/search/tag/service.name/values

Example

Example of how to query Tempo using curl. This query returns all discovered values for the tag service.name.

bash
$ curl -G -s http://localhost:3200/api/search/tag/service.name/values  | jq
{
  "tagValues": [
    "article-service",
    "auth-service",
    "billing-service",
    "cart-service",
    "postgres",
    "shop-backend"
  ],
  "metrics": {
    "inspectedBytes": "431380"
  }
}

Parameters:

  • start = (unix epoch seconds) Optional. Along with end, defines a time range from which tags should be returned.
  • end = (unix epoch seconds) Optional. Along with start, defines a time range from which tags should be returned. Providing both start and end includes blocks for the specified time range only.

Search tag values V2

This endpoint retrieves all discovered values and their data types for the given TraceQL identifier. The endpoint is available in the query frontend service in a microservices deployment, or the Tempo endpoint in a monolithic mode deployment. This endpoint is similar to /api/search/tag/<tag>/values but operates on TraceQL identifiers and types. See TraceQL documentation for more information.

Example

This example queries Tempo using curl and returns all discovered values for the tag service.name.

bash
$ curl -G -s http://localhost:3200/api/v2/search/tag/.service.name/values | jq
{
  "tagValues": [
    {
      "type": "string",
      "value": "article-service"
    },
    {
      "type": "string",
      "value": "postgres"
    },
    {
      "type": "string",
      "value": "cart-service"
    },
    {
      "type": "string",
      "value": "billing-service"
    },
    {
      "type": "string",
      "value": "shop-backend"
    },
    {
      "type": "string",
      "value": "auth-service"
    }
  ],
  "metrics": {
    "inspectedBytes": "502756"
  }
}

This endpoint can also receive start and end optional parameters. These parameters define the time range from which the tags are fetched

Filtered tag values

You can pass an optional URL query parameter, q, to your request. The q parameter is a URL-encoded TraceQL query. If provided, the tag values returned by the API are filtered to only return values seen on spans matching your filter parameters.

Queries can be incomplete: for example, { .cluster = }. Tempo extracts only the valid matchers and build a valid query.

Only queries with a single selector {} and AND && operators are supported.

  • Example supported: { .cluster = "us-east-1" && .service = "frontend" }
  • Example unsupported: { .cluster = "us-east-1" || .service = "frontend" } && { .cluster = "us-east-2" }

The following request returns all discovered service names on spans with span.http.method=GET:

GET /api/v2/search/tag/.service.name/values?q="{span.http.method='GET'}"

If a particular service name (for example, shopping-cart) is only present on spans with span.http.method=POST, it won’t be included in the list of values returned.

TraceQL Metrics

The TraceQL Metrics API returns Prometheus-like time-series for a given metrics query. Metrics queries are those using metrics functions like rate() and quantile_over_time(). Refer to the TraceQL metrics documentation for more information list.

Parameters:

  • q = (traceql query) The TraceQL metrics query to process.
  • start = (unix epoch seconds | unix epoch nanoseconds | RFC3339 string) Optional. Along with end defines the time range.
  • end = (unix epoch seconds | unix epoch nanoseconds | RFC3339 string) Optional. Along with start define the time range. Providing both start and end includes blocks for the specified time range only.
  • since = (duration string) Optional. Can be used instead of start and end to define the time range in relative values. For example, since=15m queries the last 15 minutes. Default is the last 1 hour.
  • step = (duration string) Optional. Defines the granularity of the returned time-series. For example, step=15s returns a data point every 15s within the time range. If not specified, then the default behavior chooses a dynamic step based on the time range.
  • exemplars = (integer) Optional. Defines the maximun number of exemplars for the query. It will be trimmed to max_exemplars if exceed it.

The API is available in the query frontend service in a microservices deployment, or the Tempo endpoint in a monolithic mode deployment.

For example, the following request computes the rate of spans received for myservice over the last three hours, at 1 minute intervals.

Note

Actual API parameters must be url-encoded. This example is left unencoded for readability.
GET /api/metrics/query_range?q={resource.service.name="myservice"} | min_over_time() with(exemplars=true) &since=3h&step=1m&exemplars=100

Instant

The instant version of the metrics API is similar to the range version, but instead returns a single value for the query. This version is useful when you don’t need the granularity of a full time-series, but instead want a total sum, or single value computed across the whole time range.

The parameters are identical to the range version except there is no step.

Parameters:

  • q = (traceql query) The TraceQL metrics query to process.
  • start = (unix epoch seconds | unix epoch nanoseconds | RFC3339 string) Optional. Along with end defines the time range.
  • end = (unix epoch seconds | unix epoch nanoseconds | RFC3339 string) Optional. Along with start define the time range. Providing both start and end includes blocks for the specified time range only.
  • since = (duration string) Optional. Can be used instead of start and end to define the time range in relative values. For example since=15m will query the last 15 minutes. Default is last 1 hour.

The API is available in the query frontend service in a microservices deployment, or the Tempo endpoint in a monolithic mode deployment.

For example the following request computes the total number of failed spans over the last hour per service.

Note

Actual API parameters must be url-encoded. This example is left unencoded for readability.
GET /api/metrics/query?q={status=error}|count_over_time()by(resource.service.name)

Query Echo endpoint

GET /api/echo

Returns status code 200 and body echo when the query frontend is up and ready to receive requests.

Note

Meant to be used in a Query Visualization UI like Grafana to test that the Tempo data source is working.

Overrides API

For more information about user-configurable overrides API, refer to the user-configurable overrides documentation.

Flush

GET,POST /flush

Triggers a flush of all in-memory traces to the WAL. Useful at the time of rollout restarts and unexpected crashes.

Specify the tenant parameter to flush data of a single tenant only.

GET,POST /flush?tenant=dev

Shutdown

GET,POST /shutdown

Flushes all in-memory traces and the WAL to the long term backend. Gracefully exits from the ring. Shuts down the ingester service.

Note

This is usually used at the time of scaling down a cluster.

Usage metrics

Note

This endpoint is only available when one or more usage trackers are enabled in the distributor.
GET /usage_metrics

Special metrics scrape endpoint that provides per-tenant metrics on ingested data. Per-tenant grouping rules are configured in the per-tenant overrides

Example:

curl http://localhost:3200/usage_metrics
# HELP tempo_usage_tracker_bytes_received_total bytes total received with these attributes
# TYPE tempo_usage_tracker_bytes_received_total counter
tempo_usage_tracker_bytes_received_total{service="auth-service",tenant="single-tenant",tracker="cost-attribution"} 96563
tempo_usage_tracker_bytes_received_total{service="cache",tenant="single-tenant",tracker="cost-attribution"} 81904
tempo_usage_tracker_bytes_received_total{service="gateway",tenant="single-tenant",tracker="cost-attribution"} 164751
tempo_usage_tracker_bytes_received_total{service="identity-service",tenant="single-tenant",tracker="cost-attribution"} 85974
tempo_usage_tracker_bytes_received_total{service="service-A",tenant="single-tenant",tracker="cost-attribution"} 92799

Distributor ring status

Note

This endpoint is only available when Tempo is configured with the global override strategy.
GET /distributor/ring

Displays a web page with the distributor hash ring status, including the state, healthy, and last heartbeat time of each distributor.

For more information, check the page on consistent hash ring.

Ingesters ring status

GET /ingester/ring

Displays a web page with the ingesters hash ring status, including the state, healthy, and last heartbeat time of each ingester.

_For more information, check the page on consistent hash ring.

Metrics-generator ring status

GET /metrics-generator/ring

Displays a web page with the metrics-generator hash ring status, including the state, health, and last heartbeat time of each metrics-generator.

This endpoint is only available when the metrics-generator is enabled. Refer to metrics-generator.

For more information, refer to consistent hash ring.

Compactor ring status

GET /compactor/ring

Displays a web page with the compactor hash ring status, including the state, healthy and last heartbeat time of each compactor.

For more information, refer to consistent hash ring.

Status

GET /status

Print all available information by default.

GET /status/version

Print the version information.

GET /status/services

Displays a list of services and their status. If a service failed it shows the failure case.

GET /status/endpoints

Displays status information about the API endpoints.

GET /status/config

Displays the configuration.

Displays the configuration currently applied to Tempo (in YAML format), including default values and settings via CLI flags. Sensitive data is masked. Please be aware that the exported configuration doesn’t include the per-tenant overrides.

Optional query parameter:

  • mode = (diff|defaults): diff shows the difference between the default values and the current configuration. defaults shows the default values.
GET /status/runtime_config

Displays the override configuration.

Query parameter:

  • mode = (diff): Show the difference between defaults and overrides.
GET /status/overrides

Displays all tenants that have non-default overrides configured.

GET /status/overrides/{tenant}

Displays all overrides configured for the specified tenant.

GET /status/usage-stats

Displays anonymous usage stats data that’s reported back to Grafana Labs.

List build information

GET /api/status/buildinfo

Exposes the build information in a JSON object. The fields are version, revision, branch, buildDate, buildUser, and goVersion.

Tempo GRPC API

Tempo uses GRPC to internally communicate with itself, but only has one externally supported client. The query-frontend component implements the streaming querier interface defined below. See here for the complete proto definition and generated code.

By default, this service is only offered over the GRPC port. You can use streaming service over the HTTP port as well, which Grafana expects.

To enable the streaming service over the HTTP port for use with Grafana, set the following:

stream_over_http_enabled: true

The query frontend supports the following interface. Refer to tempo.proto for complete details of all objects.

protobuf
service StreamingQuerier {
  rpc Search(SearchRequest) returns (stream SearchResponse);
  rpc SearchTags(SearchTagsRequest) returns (stream SearchTagsResponse) {}
  rpc SearchTagsV2(SearchTagsRequest) returns (stream SearchTagsV2Response) {}
  rpc SearchTagValues(SearchTagValuesRequest) returns (stream SearchTagValuesResponse) {}
  rpc SearchTagValuesV2(SearchTagValuesRequest) returns (stream SearchTagValuesV2Response) {}
  rpc MetricsQueryRange(QueryRangeRequest) returns (stream QueryRangeResponse) {}
}