Struct Template 

pub struct Template { /* private fields */ }

A templated field.

In many cases, components can be configured so that part of the component’s functionality can be customized on a per-event basis. For example, you have a sink that writes events to a file and you want to specify which file an event should go to by using an event field as part of the input to the filename used.

By using Template, users can specify either fixed strings or templated strings. Templated strings use a common syntax to refer to fields in an event that is used as the input data when rendering the template. An example of a fixed string is my-file.log. An example of a template string is my-file-{{key}}.log, where {{key}} is the key’s value when the template is rendered into a string.

Implementations

impl Template

pub const fn with_tz_offset(self, tz_offset: Option<FixedOffset>) -> Self

Set tz offset.

pub fn confine( self, config: &ConfinementConfig, component_name: &'static str, field_name: &'static str, ) -> Result<Self>

Confine this template to its literal prefix.

Consumes self and returns it with a confinement checker attached (if applicable). Three outcomes:

• dangerously_allow_unconfined_template_resolution is true — no checker attached; a SECURITY warning is emitted. Full opt-out: both startup validation and runtime checks are bypassed.
• Static template (no event-field references) — returned unchanged.
• Dynamic template with a non-empty literal prefix — checker attached.
• Dynamic template with no derivable prefix — error.

pub fn check_confinement( &self, rendered: &str, ) -> Result<(), TemplateRenderingError>

Run the confinement check attached to this template against a raw string, without going through a normal render. Callers that bypass template rendering entirely (for example the elasticsearch sink’s auto_routing path, which reads routing values directly off events) must call this to keep the confinement contract intact for those values.

Returns Ok(()) if no confinement checker is attached (static templates and pure-dynamic templates with the opt-out set both fall through this way), or if the checker accepts the value. Returns TemplateRenderingError::Confined otherwise.

pub fn render<'a>( &self, event: impl Into<EventRef<'a>>, ) -> Result<Bytes, TemplateRenderingError>

Renders the given template with data from the event, returning raw bytes.

pub fn render_string<'a>( &self, event: impl Into<EventRef<'a>>, ) -> Result<String, TemplateRenderingError>

Renders the given template with data from the event.

If a confinement check was attached at build time (see Template::confine), it runs after rendering. A confinement failure returns TemplateRenderingError::Confined — callers should emit an intentional-drop event and discard the event, not treat it as a field-missing error.

pub fn get_fields(&self) -> Option<Vec<String>>

Returns the names of the fields that are rendered in this template.

pub fn literal_prefix(&self) -> &str

Longest leading substring of the template source that is rendered verbatim — no {{ field }} reference and no strftime specifier.

Sinks use this to derive a confinement boundary from the operator-authored portion of the template.

pub fn get_ref(&self) -> &str

Returns a reference to the template string.

pub const fn is_empty(&self) -> bool

Returns true if this template string has a length of zero, and false otherwise.

pub const fn is_dynamic(&self) -> bool

A dynamic template string contains sections that depend on the input event or time.

Trait Implementations

impl Clone for Template

fn clone(&self) -> Template

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Configurable for Template

fn referenceable_name() -> Option<&'static str>

Gets the referenceable name of this value, if any.

fn metadata() -> Metadata

Gets the metadata for this value.

fn generate_schema( schema_gen: &RefCell<SchemaGenerator>, ) -> Result<SchemaObject, GenerateError>

Generates the schema for this value.

fn is_optional() -> bool

where Self: Sized,

Whether or not this value is optional.

fn validate_metadata(_metadata: &Metadata) -> Result<(), GenerateError>

where Self: Sized,

Validates the given metadata against this type.

fn as_configurable_ref() -> ConfigurableRef

where Self: Sized + 'static,

Create a new configurable reference table.

impl Debug for Template

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Template

fn default() -> Template

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for Template

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for Template

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl From<Template> for String

fn from(template: Template) -> String

Converts to this type from the input type.

impl Hash for Template

fn hash<H: Hasher>(&self, state: &mut H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for Template

fn eq(&self, other: &Self) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Serialize for Template

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl ToValue for Template

fn to_value(&self) -> Value

Convert this value into a serde_json::Value. Must not fail.

impl TryFrom<&str> for Template

type Error = TemplateParseError

The type returned in the event of a conversion error.

fn try_from(src: &str) -> Result<Self, Self::Error>

Performs the conversion.

impl TryFrom<Cow<'_, str>> for Template

type Error = TemplateParseError

The type returned in the event of a conversion error.

fn try_from(src: Cow<'_, str>) -> Result<Self, Self::Error>

Performs the conversion.

impl TryFrom<PathBuf> for Template

type Error = TemplateParseError

The type returned in the event of a conversion error.

fn try_from(p: PathBuf) -> Result<Self, Self::Error>

Performs the conversion.

impl TryFrom<String> for Template

type Error = TemplateParseError

The type returned in the event of a conversion error.

fn try_from(src: String) -> Result<Self, Self::Error>

Performs the conversion.

impl ConfigurableString for Template

impl Eq for Template