userver: Dynamic config schemas
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Dynamic config schemas

Here you can find schemas of dynamic configs used by userver itself. For general information on dynamic configs, see Dynamic config

HTTP_CLIENT_CONNECT_THROTTLE

Token bucket throttling options for new connections (socket(3)).

  • *-limit - token bucket size, set to 0 to disable the limit
  • *-per-second - token bucket size refill speed
yaml
schema:
type: object
properties:
http-limit:
type: integer
minimum: 0
http-per-second:
type: integer
minimum: 0
https-limit:
type: integer
minimum: 0
https-per-second:
type: integer
minimum: 0
per-host-limit:
type: integer
minimum: 0
per-host-per-second:
type: integer
minimum: 0
additionalProperties: false
required:
- http-limit
- https-limit
- per-host-limit

Example:

{
"http-limit": 6000,
"http-per-second": 1500,
"https-limit": 100,
"https-per-second": 25,
"per-host-limit": 3000,
"per-host-per-second": 500
}

Used by components::HttpClient, affects the behavior of clients::http::Client and all the clients that use it.

HTTP_CLIENT_CONNECTION_POOL_SIZE

Open connections pool size for curl (CURLMOPT_MAXCONNECTS). -1 means "detect by multiplying easy handles count on 4".

schema:
type: integer

Example:

5000

Used by components::HttpClient, affects the behavior of clients::http::Client and all the clients that use it.

MONGO_DEFAULT_MAX_TIME_MS

Dynamic config that controls default $maxTimeMS for mongo requests (0 - disables default timeout).

yaml
schema:
type: integer
minimum: 0

Example:

200

Used by components::Mongo, components::MultiMongo.

MONGO_DEADLINE_PROPAGATION_ENABLED_V2

Dynamic config that controls whether task-inherited deadline is accounted for while executing mongodb queries.

yaml
schema:
type: boolean

Example:

false

Used by components::Mongo, components::MultiMongo.

POSTGRES_DEFAULT_COMMAND_CONTROL

Dynamic config that controls default network and statement timeouts. Overrides the built-in timeouts from components::Postgres::kDefaultCommandControl, but could be overridden by POSTGRES_HANDLERS_COMMAND_CONTROL, POSTGRES_QUERIES_COMMAND_CONTROL and storages::postgres::CommandControl.

yaml
type: object
additionalProperties: false
properties:
network_timeout_ms:
type: integer
minimum: 1
statement_timeout_ms:
type: integer
minimum: 1

Example:

{
"network_timeout_ms": 750,
"statement_timeout_ms": 500
}

Used by components::Postgres.

POSTGRES_HANDLERS_COMMAND_CONTROL

Dynamic config that controls per-handle statement and network timeouts. Overrides POSTGRES_DEFAULT_COMMAND_CONTROL and built-in timeouts from components::Postgres::kDefaultCommandControl, but may be overridden by POSTGRES_QUERIES_COMMAND_CONTROL and storages::postgres::CommandControl.

yaml
type: object
additionalProperties:
$ref: "#/definitions/CommandControlByMethodMap"
definitions:
CommandControlByMethodMap:
type: object
additionalProperties:
$ref: "#/definitions/CommandControl"
CommandControl:
type: object
additionalProperties: false
properties:
network_timeout_ms:
type: integer
minimum: 1
statement_timeout_ms:
type: integer
minimum: 1

Example:

{
"/v2/rules/create": {
"POST": {
"network_timeout_ms": 500,
"statement_timeout_ms": 250
}
},
"/v2/rules/select": {
"POST": {
"network_timeout_ms": 70,
"statement_timeout_ms": 30
}
}
}

Used by components::Postgres.

POSTGRES_QUERIES_COMMAND_CONTROL

Dynamic config that controls per-query/per-transaction statement and network timeouts, if those were not explicitly set via storages::postgres::CommandControl. Overrides the POSTGRES_HANDLERS_COMMAND_CONTROL, POSTGRES_QUERIES_COMMAND_CONTROL, POSTGRES_DEFAULT_COMMAND_CONTROL, and built-in timeouts from components::Postgres::kDefaultCommandControl.

Transaction timeouts in POSTGRES_QUERIES_COMMAND_CONTROL override the per-query timeouts in POSTGRES_QUERIES_COMMAND_CONTROL, so the latter are ignored if transaction timeouts are set.

yaml
type: object
additionalProperties:
$ref: "#/definitions/CommandControl"
definitions:
CommandControl:
type: object
additionalProperties: false
properties:
network_timeout_ms:
type: integer
minimum: 1
statement_timeout_ms:
type: integer
minimum: 1

Example:

{
"cleanup_processed_data": {
"network_timeout_ms": 92000,
"statement_timeout_ms": 90000
},
"select_recent_users": {
"network_timeout_ms": 70,
"statement_timeout_ms": 30
}
}

Used by components::Postgres.

POSTGRES_CONNECTION_POOL_SETTINGS

Dynamic config that controls connection pool settings of PostgreSQL driver.

Dictionary keys can be either the service component name (not database name!) or __default__. The latter configuration is applied for every non-matching PostgreSQL component of the service.

Take note that it overrides the static configuration values of the service!

yaml
type: object
additionalProperties:
$ref: "#/definitions/PoolSettings"
definitions:
PoolSettings:
type: object
additionalProperties: false
properties:
min_pool_size:
type: integer
minimum: 0
max_pool_size:
type: integer
minimum: 1
max_queue_size:
type: integer
minimum: 1
connecting_limit:
type: integer
minimum: 0
required:
- min_pool_size
- max_pool_size
- max_queue_size

Example:

{
"__default__": {
"min_pool_size": 4,
"max_pool_size": 15,
"max_queue_size": 200,
"connecting_limit": 10
},
"postgresql-orders": {
"min_pool_size": 8,
"max_pool_size": 50,
"max_queue_size": 200,
"connecting_limit": 8
}
}

Used by components::Postgres.

POSTGRES_TOPOLOGY_SETTINGS

Dynamic config that controls topology settings of service's PostgreSQL components.

Dictionary keys can be either the service component name (not database name!) or __default__. The latter configuration is applied for every non-matching PostgreSQL component of the service.

Take note that it overrides the static configuration values of the service!

yaml
type: object
additionalProperties: false
properties:
max_replication_lag_ms:
type: integer
minimum: 0
description: maximum allowed replication lag. If equals 0 no replication
lag checks are performed
required:
- max_replication_lag_ms

Example

{
"__default__": {
"max_replication_lag_ms": 60000
}
}

Used by components::Postgres.

POSTGRES_CONNECTION_SETTINGS

Dynamic config that controls settings for newly created connections of PostgreSQL driver.

Dictionary keys can be either the service component name (not database name!) or __default__. The latter configuration is applied for every non-matching PostgreSQL component of the service.

Take note that it overrides the static configuration values of the service!

yaml
type: object
additionalProperties: false
properties:
persistent-prepared-statements:
type: boolean
default: true
user-types-enabled:
type: boolean
default: true
max-prepared-cache-size:
type: integer
minimum: 1
default: 5000
recent-errors-threshold:
type: integer
minimum: 1
ignore-unused-query-params:
type: boolean
default: false
max-ttl-sec:
type integer
minimum: 1

Example:

{
"__default__": {
"persistent-prepared-statements": true,
"user-types-enabled": true,
"max-prepared-cache-size": 5000,
"ignore-unused-query-params": false,
"recent-errors-threshold": 2,
"max-ttl-sec": 3600
}
}

Used by components::Postgres.

POSTGRES_CONNLIMIT_MODE_AUTO_ENABLED

Dynamic config that enables connlimit_mode: auto for PostgreSQL connections. Auto mode ignores static and dynamic max_connections configs and verifies that the cluster services use max_connections equals to PostgreSQL server's max_connections divided by service instance count.

yaml
default: true
schema:
type: boolean

Used by components::Postgres.

POSTGRES_STATEMENT_METRICS_SETTINGS

Dynamic config that controls statement metrics settings for specific service.

Dictionary keys can be either the service component name (not database name!) or __default__. The latter configuration is applied for every non-matching PostgreSQL component of the service.

The value of max_statement_metrics controls the maximum size of LRU-cache for named statement metrics. When set to 0 (default) no metrics are being exported.

The exported data can be found as postgresql.statement_timings.

yaml
type: object
additionalProperties:
$ref: "#/definitions/StatementMetricsSettings"
definitions:
StatementMetricsSettings:
type: object
additionalProperties: false
properties:
max_statement_metrics:
type: integer
minimum: 0
{
"postgresql-database_name": {
"max_statement_metrics": 50
},
"__default__": {
"max_statement_metrics": 150
}
}

Used by components::Postgres.

REDIS_COMMANDS_BUFFERING_SETTINGS

Dynamic config that controls command buffering for specific service. Enabling of this config activates a delay in sending commands. When commands are sent, they are combined into a single tcp packet and sent together. First command arms timer and then during watch_command_timer_interval_us commands are accumulated in the buffer

Command buffering is disabled by default.

yaml
type: object
additionalProperties: false
properties:
buffering_enabled:
type: boolean
commands_buffering_threshold:
type: integer
minimum: 1
watch_command_timer_interval_us:
type: integer
minimum: 0
required:
- buffering_enabled
- watch_command_timer_interval_us

Example:

{
"buffering_enabled": true,
"commands_buffering_threshold": 10,
"watch_command_timer_interval_us": 1000
}

Used by components::Redis.

REDIS_DEFAULT_COMMAND_CONTROL

Dynamic config that overrides the default timeouts, number of retries and server selection strategy for redis commands.

yaml
type: object
additionalProperties: false
properties:
best_dc_count:
type: integer
max_ping_latency_ms:
type: integer
max_retries:
type: integer
strategy:
enum:
- default
- every_dc
- local_dc_conductor
- nearest_server_ping
type: string
timeout_all_ms:
type: integer
timeout_single_ms:
type: integer

Example:

{
"best_dc_count": 0,
"max_ping_latency_ms": 0,
"max_retries": 4,
"strategy": "default",
"timeout_all_ms": 2000,
"timeout_single_ms": 500
}

Used by components::Redis.

REDIS_METRICS_SETTINGS

Dynamic config that controls the metric settings for specific service.

Dictionary keys can be either the database name (not the component name!) or __default__. The latter configuration is applied for every non-matching Redis database/sentinel of the service.

yaml
type: object
additionalProperties:
$ref: "#/definitions/MetricsSettings"
definitions:
MetricsSettings:
type: object
additionalProperties: false
properties:
timings-enabled:
type: boolean
default: true
description: enable timings statistics
command-timings-enabled:
type: boolean
default: false
description: enable statistics for individual commands
request-sizes-enabled:
type: boolean
default: false
description: enable request sizes statistics
reply-sizes-enabled:
type: boolean
default: false
description: enable response sizes statistics

Example:

{
"redis-database_name": {
"timings-enabled": true,
"command-timings-enabled": false,
"request-sizes-enabled": false,
"reply-sizes-enabled": false
}
}

Used by components::Redis.

REDIS_PUBSUB_METRICS_SETTINGS

Dynamic config that controls the redis pubsub metric settings for specific service.

Dictionary keys can be either the database name (not the component name!) or __default__. The latter configuration is applied for every non-matching Redis database/sentinel of the service.

yaml
type: object
additionalProperties:
$ref: "#/definitions/PubsubMetricsSettings"
definitions:
PubsubMetricsSettings:
type: object
additionalProperties: false
properties:
per-shard-stats-enabled:
type: boolean
default: true
description: enable collecting statistics by shard

Example:

{
"redis-database_name": {
"per-shard-stats-enabled": true
}
}

Used by components::Redis.

REDIS_RETRY_BUDGET_SETTINGS

Dynamic config that controls the retry budget (throttling) settings for components::Redis.

Dictionary keys can be either the database name (not the component name!) or __default__. The latter configuration is applied for every non-matching Redis database/sentinel of the service.

yaml
type: object
additionalProperties:
$ref: '#/definitions/BaseSettings'
definitions:
BaseSettings:
type: object
additionalProperties: false
properties:
enabled:
description: Enable retry budget for database
type: boolean
max-tokens:
description: Number of tokens to start with
type: number
maximum: 1000
minimum: 1
token-ratio:
description: Amount of tokens added on each successful request
type: number
maximum: 1
minimum: 0.001
required:
- enabled
- max-tokens
- token-ratio

Example:

{
"__default__": {
"max-tokens": 100,
"token-ratio": 0.1,
"enabled": true
}
}

Used by components::Redis.

REDIS_REPLICA_MONITORING_SETTINGS

Настройки отслеживания синхронизации реплик redis

Dynamic config that controls the monitoring settings for synchronizing replicas.

Dictionary keys can be either the database name (not the component name!) or __default__. The latter configuration is applied for every non-matching Redis database/sentinel of the service.

yaml
type: object
additionalProperties:
$ref: '#/definitions/BaseSettings'
definitions:
BaseSettings:
type: object
additionalProperties: false
properties:
enable-monitoring:
description: set to `true` to turn on monitoring
type: boolean
forbid-requests-to-syncing-replicas:
description: set to true to forbid requests to syncing replicas
type: boolean
required:
- enable-monitoring
- forbid-requests-to-syncing-replicas

Used by components::Redis.

Example:

{
"__default__": {
"enable-monitoring": false,
"forbid-requests-to-syncing-replicas": false
}
}

REDIS_SUBSCRIBER_DEFAULT_COMMAND_CONTROL

The same as REDIS_DEFAULT_COMMAND_CONTROL but for subscription clients.

yaml
type: object
additionalProperties: false
properties:
timeout_single_ms:
type: integer
minimum: 1
timeout_all_ms:
type: integer
minimum: 1
best_dc_count:
type: integer
minimum: 1
max_ping_latency_ms:
type: integer
minimum: 1
strategy:
type: string
enum:
- default
- every_dc
- local_dc_conductor
- nearest_server_ping

Example:

{
"best_dc_count": 0,
"max_ping_latency_ms": 0,
"strategy": "default",
"timeout_all_ms": 2000,
"timeout_single_ms": 500
}

Used by components::Redis.

REDIS_SUBSCRIPTIONS_REBALANCE_MIN_INTERVAL_SECONDS

Dynamic config that controls the minimal interval between redis subscription clients rebalancing.

yaml
minimum: 0
type: integer
default: 30

Used by components::Redis.

REDIS_WAIT_CONNECTED

Dynamic config that controls if services will wait for connections with redis instances.

yaml
type: object
additionalProperties: false
properties:
mode:
type: string
enum:
- no_wait
- master
- slave
- master_or_slave
- master_and_slave
throw_on_fail:
type: boolean
timeout-ms:
type: integer
minimum: 1
x-taxi-cpp-type: std::chrono::milliseconds
required:
- mode
- throw_on_fail
- timeout-ms

Example:

{
"mode": "master_or_slave",
"throw_on_fail": false,
"timeout-ms": 11000
}

Used by components::Redis.

USERVER_CACHES

Cache update dynamic parameters.

yaml
schema:
type: object
additionalProperties:
type: object
additionalProperties: false
properties:
update-interval-ms:
type: integer
minimum: 1
update-jitter-ms:
type: integer
minimum: 0
full-update-interval-ms:
type: integer
minimum: 0
updates-enabled:
type: boolean
default: true
exception-interval-ms:
type: integer
minimum: 0
alert-on-failing-to-update-times:
type: integer
minimum: 0
required:
- update-interval-ms
- update-jitter-ms
- full-update-interval-ms

Example:

{
"some-cache-name": {
"full-update-interval-ms": 86400000,
"update-interval-ms": 30000,
"update-jitter-ms": 1000,
"alert-on-failing-to-update-times": 2
}
}

Used by all the caches derived from components::CachingComponentBase.

USERVER_CANCEL_HANDLE_REQUEST_BY_DEADLINE

Controls whether the http request task should be cancelled when the deadline received from the client is reached.

yaml
schema:
type: boolean

Example:

true

Used by components::Server.

USERVER_DEADLINE_PROPAGATION_ENABLED

When false, disables deadline propagation in the service. This includes:

  • reading the task-inherited deadline from HTTP headers and gRPC metadata;
  • interrupting operations when deadline expires;
  • propagating the deadline to downstream services and databases.
yaml
schema:
type: boolean

Example:

true

Used by components::Server and ugrpc::server::ServerComponent.

USERVER_DUMPS

Dynamic dump configuration. If the options are set for some dump then those options override the static configuration.

yaml
schema:
type: object
additionalProperties:
type: object
additionalProperties: false
properties:
dumps-enabled:
type: boolean
min-dump-interval:
description: dump interval in milliseconds
type: integer
minimum: 0

Example:

{
"some-cache-name": {
"dumps-enabled": true,
"min-dump-interval": 100000
}
}

Used by dump::Dumper, especially by all the caches derived from components::CachingComponentBase.

USERVER_HANDLER_STREAM_API_ENABLED

Sets whether Stream API should be enabled for HTTP handlers.

yaml
schema:
type: boolean

Example:

true

USERVER_HTTP_PROXY

Proxy for all the HTTP and HTTPS clients. Empty string disables proxy usage.

Proxy string may be prefixed with [scheme]:// to specify which kind of proxy is used. Schemes match the libcurl supported ones. A proxy host string can also embed user and password.

yaml
schema:
type: string

Example:

localhost:8090

Used by components::HttpClient, affects the behavior of clients::http::Client and all the clients that use it.

USERVER_LOG_DYNAMIC_DEBUG

Logging per line and file overrides. Log locations are defined as path prefix from the Arcadia root ("taxi/uservices/services/"). Location of file may be followed by :[line index] to specify 1 exact log in that file.

yaml
default:
force-enabled: []
force-disabled: []
schema:
type: object
additionalProperties: false
required:
- force-enabled
- force-disabled
properties:
force-enabled:
type: array
description: Locations of logs to turn on. This option is deprecated, consider using "force-enabled-level" instead.
items:
type: string
force-disabled:
type: array
description: Locations of logs to turn off, logs with level WARNING and higher will not be affected.
This option is deprecated, consider using "force-disabled-level" instead.
items:
type: string
force-enabled-level:
type: object
description: |
Locations of logs to turn on with level equal or higher to given.
For example, to turn on all logs with level WARNING or higher in "userver/grpc",
all logs with level DEBUG or higher in file "userver/core/src/server/server.cpp"
and 1 log (since exact line is specified) with level TRACE in file "userver/core/src/server/http/http_request_parser.cpp":
"force-enabled-level": {
"taxi/uservices/userver/grpc": "WARNING",
"taxi/uservices/userver/core/src/server/server.cpp": "DEBUG",
"taxi/uservices/userver/core/src/server/http/http_request_parser.cpp:128": "TRACE"
}
additionalProperties:
type: string
force-disabled-level:
type: object
description: |
Locations of logs to turn off with level equal or lower to given.
For example, to turn off all logs with level ERROR or lower in "userver/grpc",
all logs with level INFO or lower in file "userver/core/src/server/server.cpp"
and 1 log (since exact line is specified) with level TRACE in file "userver/core/src/server/http/http_request_parser.cpp":
"force-disabled-level": {
"taxi/uservices/userver/grpc": "ERROR",
"taxi/uservices/userver/core/src/server/server.cpp": "INFO",
"taxi/uservices/userver/core/src/server/http/http_request_parser.cpp:128": "TRACE"
}
additionalProperties:
type: string

Used by components::LoggingConfigurator.

USERVER_LOG_REQUEST

Controls HTTP requests and responses logging.

yaml
schema:
type: boolean

Example:

false

Used by components::Server.

USERVER_LOG_REQUEST_HEADERS

Controls whether the logging of HTTP headers in handlers is performed.

yaml
schema:
type: boolean

Example:

false

Used by components::Server.

USERVER_LRU_CACHES

Dynamic config for controlling size and cache entry lifetime of the LRU based caches.

yaml
schema:
type: object
additionalProperties:
$ref: '#/definitions/CacheSettings'
definitions:
CacheSettings:
type: object
properties:
size:
type: integer
lifetime-ms:
type: integer
required:
- size
- lifetime-ms
additionalProperties: false

Example:

{
"some-cache-name": {
"lifetime-ms": 5000,
"size": 100000
},
"some-other-cache-name": {
"lifetime-ms": 5000,
"size": 400000
}
}

Used by all the caches derived from cache::LruCacheComponent.

USERVER_NO_LOG_SPANS

Prefixes or full names of tracing::Span instances to not log.

yaml
schema:
type: object
additionalProperties: false
required:
- prefixes
- names
properties:
prefixes:
type: array
items:
type: string
names:
type: array
items:
type: string

Example:

{
"names": [
"mongo_find"
],
"prefixes": [
"http",
"handler"
]
}

Used by components::LoggingConfigurator and all the logging facilities.

USERVER_RPS_CCONTROL

Dynamic config for components::Server congestion control.

yaml
schema:
type: object
additionalProperties: false
properties:
min-limit:
type: integer
minimum: 1
description: |
Minimal RPS limit value.
up-rate-percent:
type: number
minimum: 0
exclusiveMinimum: true
description: |
On how many percents increase the RPS limit every second if not in overloaded state.
down-rate-percent:
type: number
minimum: 0
maximum: 100
exclusiveMinimum: true
description: |
On how many percents decrease the RPS limit every second if in overloaded state.
overload-on-seconds:
type: integer
minimum: 1
description: |
How many seconds overload should be higher than `up-level`,
to switch to overload state and start limiting RPS.
overload-off-seconds:
type: integer
minimum: 1
description: |
How many seconds overload should be higher than `down-level`,
to switch from overload state and the RPS limit start increasing.
up-level:
type: integer
minimum: 1
description: |
Overload level that should least for `overload-on-seconds` to switch to
overloaded state.
down-level:
type: integer
minimum: 1
description: |
Overload level that should least for `overload-on-seconds` to
increase RPS limits.
no-limit-seconds:
type: integer
minimum: 1
description: |
Seconds without overload to switch from overloaded state and
remove all the RPS limits.
load-limit-crit-percent:
type: integer
description: |
On reaching this load percent immediately switch to overloaded state.

Example:

{
"down-level": 8,
"down-rate-percent": 1,
"load-limit-crit-percent": 70,
"min-limit": 2,
"no-limit-seconds": 120,
"overload-off-seconds": 8,
"overload-on-seconds": 8,
"up-level": 2,
"up-rate-percent": 1
}

Used by congestion_control::Component.

USERVER_RPS_CCONTROL_ENABLED

Controls whether congestion control limiting of RPS is performed (if main task processor is overloaded, then the server starts rejecting some requests).

yaml
schema:
type: boolean

Example:

true

Used by congestion_control::Component.

USERVER_TASK_PROCESSOR_PROFILER_DEBUG

Dynamic config for profiling the coroutine based engine of userver. Dictionary key names are the names of engine::TaskProcessor.

yaml
schema:
type: object
properties: {}
additionalProperties:
$ref: '#/definitions/TaskProcessorSettings'
definitions:
TaskProcessorSettings:
type: object
required:
- enabled
- execution-slice-threshold-us
additionalProperties: false
properties:
enabled:
type: boolean
description: |
Set to `true` to turn on the profiling
execution-slice-threshold-us:
type: integer
description: |
Execution threshold of a coroutine on a thread without context switch.
If the threshold is reached then the coroutine is logged, otherwise
does nothing.
minimum: 1

Example:

{
"fs-task-processor": {
"enabled": false,
"execution-slice-threshold-us": 1000000
},
"main-task-processor": {
"enabled": false,
"execution-slice-threshold-us": 2000
}
}

Used by components::ManagerControllerComponent.

USERVER_TASK_PROCESSOR_QOS

Controls engine::TaskProcessor quality of service dynamic config.

yaml
schema:
type: object
required:
- default-service
additionalProperties: false
properties:
default-service:
type: object
additionalProperties: false
required:
- default-task-processor
properties:
default-task-processor:
type: object
additionalProperties: false
required:
- wait_queue_overload
properties:
wait_queue_overload:
type: object
additionalProperties: false
required:
- time_limit_us
- length_limit
- action
properties:
time_limit_us:
type: integer
minimum: 0
description: |
Wait in queue time after which the `action is applied`.
length_limit:
type: integer
minimum: 0
description: |
Queue size after which the `action` is applied.
action
action:
type: string
enum:
- ignore
- cancel
description: |
Action to perform on tasks on queue overload.
`cancel` - cancels the tasks
sensor_time_limit_us:
type: integer
minimum: 0
description: |
Wait in queue time after which the overload events for
RPS congestion control are generated.

Example:

{
"default-service": {
"default-task-processor": {
"wait_queue_overload": {
"action": "cancel",
"length_limit": 5000,
"sensor_time_limit_us": 12000,
"time_limit_us": 0
}
}
}
}

Used by components::ManagerControllerComponent.

USERVER_FILES_CONTENT_TYPE_MAP

Dynamic config for mapping extension files with HTTP header content type.

yaml
schema:
type: object
additionalProperties:
type: string

Example:

{
".css": "text/css",
".gif": "image/gif",
".htm": "text/html",
".html": "text/html",
".jpeg": "image/jpeg",
".js": "application/javascript",
".json": "application/json",
".md": "text/markdown",
".png": "image/png",
".svg": "image/svg+xml",
"__default__": "text/plain"
}

Used by server::handlers::HttpHandlerStatic