fastmcp.resources.template

Resource template functionality.

Functions

extract_query_params ^{<a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/resources/template.py#L39" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a>}

extract_query_params(uri_template: str) -> set[str]

Extract query parameter names from RFC 6570 {?param1,param2} syntax.

build_regex ^{<a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/resources/template.py#L47" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a>}

build_regex(template: str) -> re.Pattern[str] | None

Build regex pattern for URI template, handling RFC 6570 syntax.

Supports:

• {var} - simple path parameter
• {var*} - wildcard path parameter (captures multiple segments)
• {?var1,var2} - query parameters (ignored in path matching)

Returns None if the template produces an invalid regex (e.g. parameter names with hyphens, leading digits, or duplicates from a remote server).

match_uri_template ^{<a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/resources/template.py#L79" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a>}

match_uri_template(uri: str, uri_template: str) -> dict[str, str] | None

Match URI against template and extract both path and query parameters.

Supports RFC 6570 URI templates:

• Path params: {var}, {var*}
• Query params: {?var1,var2}

expand_uri_template ^{<a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/resources/template.py#L112" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a>}

expand_uri_template(uri_template: str, params: dict[str, Any]) -> str

Expand a URI template with parameters — inverse of match_uri_template.

Supports the same RFC 6570 subset:

• Path params: {var}, {var*}
• Query params: {?var1,var2}

Classes

ResourceTemplate ^{<a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/resources/template.py#L144" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a>}

A template for dynamically creating resources.

Methods:

from_function ^{<a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/resources/template.py#L171" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a>}

from_function(fn: Callable[..., Any], uri_template: str, name: str | None = None, version: str | int | None = None, title: str | None = None, description: str | None = None, icons: list[Icon] | None = None, mime_type: str | None = None, tags: set[str] | None = None, annotations: Annotations | None = None, meta: dict[str, Any] | None = None, task: bool | TaskConfig | None = None, auth: AuthCheck | list[AuthCheck] | None = None) -> FunctionResourceTemplate

set_default_mime_type ^{<a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/resources/template.py#L204" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a>}

set_default_mime_type(cls, mime_type: str | None) -> str

Set default MIME type if not provided.

matches ^{<a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/resources/template.py#L210" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a>}

matches(self, uri: str) -> dict[str, Any] | None

Check if URI matches template and extract parameters.

read ^{<a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/resources/template.py#L214" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a>}

read(self, arguments: dict[str, Any]) -> str | bytes | ResourceResult

Read the resource content.

convert_result ^{<a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/resources/template.py#L220" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a>}

convert_result(self, raw_value: Any) -> ResourceResult

Convert a raw result to ResourceResult.

This is used in two contexts:

1. In _read() to convert user function return values to ResourceResult
2. In tasks_result_handler() to convert Docket task results to ResourceResult

Handles ResourceResult passthrough and converts raw values using ResourceResult's normalization.

create_resource ^{<a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/resources/template.py#L284" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a>}

create_resource(self, uri: str, params: dict[str, Any]) -> Resource

Create a resource from the template with the given parameters.

The base implementation does not support background tasks. Use FunctionResourceTemplate for task support.

to_mcp_template ^{<a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/resources/template.py#L295" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a>}

to_mcp_template(self, **overrides: Any) -> SDKResourceTemplate

Convert the resource template to an SDKResourceTemplate.

from_mcp_template ^{<a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/resources/template.py#L315" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a>}

from_mcp_template(cls, mcp_template: SDKResourceTemplate) -> ResourceTemplate

Creates a FastMCP ResourceTemplate from a raw MCP ResourceTemplate object.

key ^{<a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/resources/template.py#L328" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a>}

key(self) -> str

The globally unique lookup key for this template.

register_with_docket ^{<a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/resources/template.py#L333" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a>}

register_with_docket(self, docket: Docket) -> None

Register this template with docket for background execution.

add_to_docket ^{<a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/resources/template.py#L339" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a>}

add_to_docket(self, docket: Docket, params: dict[str, Any], **kwargs: Any) -> Execution

Schedule this template for background execution via docket.

Args:

• docket: The Docket instance
• params: Template parameters
• fn_key: Function lookup key in Docket registry (defaults to self.key)
• task_key: Redis storage key for the result
• **kwargs: Additional kwargs passed to docket.add()

get_span_attributes ^{<a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/resources/template.py#L362" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a>}

get_span_attributes(self) -> dict[str, Any]

FunctionResourceTemplate ^{<a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/resources/template.py#L369" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a>}

A template for dynamically creating resources.

Methods:

create_resource ^{<a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/resources/template.py#L415" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a>}

create_resource(self, uri: str, params: dict[str, Any]) -> Resource

Create a resource from the template with the given parameters.

read ^{<a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/resources/template.py#L434" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a>}

read(self, arguments: dict[str, Any]) -> str | bytes | ResourceResult

Read the resource content.

register_with_docket ^{<a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/resources/template.py#L473" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a>}

register_with_docket(self, docket: Docket) -> None

Register this template with docket for background execution.

add_to_docket ^{<a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/resources/template.py#L479" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a>}

add_to_docket(self, docket: Docket, params: dict[str, Any], **kwargs: Any) -> Execution

Schedule this template for background execution via docket.

FunctionResourceTemplate splats the params dict since .fn expects **kwargs.

Args:

• docket: The Docket instance
• params: Template parameters
• fn_key: Function lookup key in Docket registry (defaults to self.key)
• task_key: Redis storage key for the result
• **kwargs: Additional kwargs passed to docket.add()

from_function ^{<a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/resources/template.py#L505" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a>}

from_function(cls, fn: Callable[..., Any], uri_template: str, name: str | None = None, version: str | int | None = None, title: str | None = None, description: str | None = None, icons: list[Icon] | None = None, mime_type: str | None = None, tags: set[str] | None = None, annotations: Annotations | None = None, meta: dict[str, Any] | None = None, task: bool | TaskConfig | None = None, auth: AuthCheck | list[AuthCheck] | None = None) -> FunctionResourceTemplate

Create a template from a function.