Documentation
¶
Index ¶
- Variables
- func ConfigBlockID(block *ast.BlockStmt) string
- type ComponentGlobals
- type ComponentID
- type ComponentNode
- func (cn *ComponentNode) Arguments() component.Arguments
- func (cn *ComponentNode) ComponentName() string
- func (cn *ComponentNode) CurrentHealth() component.Health
- func (cn *ComponentNode) DebugInfo() interface{}
- func (cn *ComponentNode) Evaluate(scope *vm.Scope) error
- func (cn *ComponentNode) Exports() component.Exports
- func (cn *ComponentNode) HTTPHandler() http.Handler
- func (cn *ComponentNode) ID() ComponentID
- func (cn *ComponentNode) Label() string
- func (cn *ComponentNode) NodeID() string
- func (cn *ComponentNode) Run(ctx context.Context) error
- func (cn *ComponentNode) UpdateBlock(b *ast.BlockStmt)
- type ConfigNode
- type Loader
- func (l *Loader) Apply(parentScope *vm.Scope, blocks []*ast.BlockStmt, configBlocks []*ast.BlockStmt) diag.Diagnostics
- func (l *Loader) Components() []*ComponentNode
- func (l *Loader) EvaluateDependencies(parentScope *vm.Scope, c *ComponentNode)
- func (l *Loader) Graph() *dag.Graph
- func (l *Loader) OriginalGraph() *dag.Graph
- func (l *Loader) Variables() map[string]interface{}
- type Queue
- type Reference
- type RunnableNode
- type Scheduler
- type Traversal
Constants ¶
This section is empty.
Variables ¶
var ErrUnevaluated = errors.New("managed component not built")
ErrUnevaluated is returned if ComponentNode.Run is called before a managed component is built.
Functions ¶
func ConfigBlockID ¶ added in v0.29.0
func ConfigBlockID(block *ast.BlockStmt) string
ConfigBlockID returns the string name for a config block.
Types ¶
type ComponentGlobals ¶
type ComponentGlobals struct {
Logger log.Logger // Logger shared between all managed components.
TraceProvider trace.TracerProvider // Tracer shared between all managed components.
DataPath string // Shared directory where component data may be stored
OnExportsChange func(cn *ComponentNode) // Invoked when the managed component updated its exports
Registerer prometheus.Registerer // Registerer for serving agent and component metrics
HTTPListenAddr string // Base address for server
}
ComponentGlobals are used by ComponentNodes to build managed components. All ComponentNodes should use the same ComponentGlobals.
type ComponentID ¶
type ComponentID []string
ComponentID is a fully-qualified name of a component. Each element in ComponentID corresponds to a fragment of the period-delimited string; "remote.http.example" is ComponentID{"remote", "http", "example"}.
func BlockComponentID ¶
func BlockComponentID(b *ast.BlockStmt) ComponentID
BlockComponentID returns the ComponentID specified by an River block.
type ComponentNode ¶
type ComponentNode struct {
// contains filtered or unexported fields
}
ComponentNode is a controller node which manages a user-defined component.
ComponentNode manages the underlying component and caches its current arguments and exports. ComponentNode manages the arguments for the component from a River block.
func NewComponentNode ¶
func NewComponentNode(globals ComponentGlobals, b *ast.BlockStmt) *ComponentNode
NewComponentNode creates a new ComponentNode from an initial ast.BlockStmt. The underlying managed component isn't created until Evaluate is called.
func (*ComponentNode) Arguments ¶
func (cn *ComponentNode) Arguments() component.Arguments
Arguments returns the current arguments of the managed component.
func (*ComponentNode) ComponentName ¶ added in v0.28.0
func (cn *ComponentNode) ComponentName() string
ComponentName returns the component's type, i.e. `local.file.test` returns `local.file`.
func (*ComponentNode) CurrentHealth ¶
func (cn *ComponentNode) CurrentHealth() component.Health
CurrentHealth returns the current health of the ComponentNode.
The health of a ComponentNode is tracked from three parts, in descending precedence order:
- Exited health from a call to Run()
- Unhealthy status from last call to Evaluate
- Health reported by the managed component (if any)
- Latest health from Run() or Evaluate(), if the managed component does not report health.
func (*ComponentNode) DebugInfo ¶
func (cn *ComponentNode) DebugInfo() interface{}
DebugInfo returns debugging information from the managed component (if any).
func (*ComponentNode) Evaluate ¶
func (cn *ComponentNode) Evaluate(scope *vm.Scope) error
Evaluate updates the arguments for the managed component by re-evaluating its River block with the provided scope. The managed component will be built the first time Evaluate is called.
Evaluate will return an error if the River block cannot be evaluated or if decoding to arguments fails.
func (*ComponentNode) Exports ¶
func (cn *ComponentNode) Exports() component.Exports
Exports returns the current set of exports from the managed component. Exports returns nil if the managed component does not have exports.
func (*ComponentNode) HTTPHandler ¶ added in v0.28.0
func (cn *ComponentNode) HTTPHandler() http.Handler
HTTPHandler returns an http handler for a component IF it implements HTTPComponent. otherwise it will return nil.
func (*ComponentNode) ID ¶
func (cn *ComponentNode) ID() ComponentID
ID returns the component ID of the managed component from its River block.
func (*ComponentNode) Label ¶ added in v0.28.0
func (cn *ComponentNode) Label() string
Label returns the label for the block or "" if none was specified.
func (*ComponentNode) NodeID ¶
func (cn *ComponentNode) NodeID() string
NodeID implements dag.Node and returns the unique ID for this node. The NodeID is the string representation of the component's ID from its River block.
func (*ComponentNode) Run ¶
func (cn *ComponentNode) Run(ctx context.Context) error
Run runs the managed component in the calling goroutine until ctx is canceled. Evaluate must have been called at least once without retuning an error before calling Run.
Run will immediately return ErrUnevaluated if Evaluate has never been called successfully. Otherwise, Run will return nil.
func (*ComponentNode) UpdateBlock ¶
func (cn *ComponentNode) UpdateBlock(b *ast.BlockStmt)
UpdateBlock updates the River block used to construct arguments for the managed component. The new block isn't used until the next time Evaluate is invoked.
UpdateBlock will panic if the block does not match the component ID of the ComponentNode.
type ConfigNode ¶ added in v0.29.0
type ConfigNode struct {
// contains filtered or unexported fields
}
ConfigNode is a controller node which manages agent configuration. The graph will always have _exactly one_ instance of ConfigNode, which will be used to contain the state of all config blocks.
func NewConfigNode ¶ added in v0.29.0
func NewConfigNode(blocks []*ast.BlockStmt, l log.Logger, t trace.TracerProvider) (*ConfigNode, diag.Diagnostics)
NewConfigNode creates a new ConfigNode from an initial ast.BlockStmt. The underlying config isn't applied until Evaluate is called.
func (*ConfigNode) Evaluate ¶ added in v0.29.0
func (cn *ConfigNode) Evaluate(scope *vm.Scope) (*ast.BlockStmt, error)
Evaluate updates the config block by re-evaluating its River block with the provided scope. The config will be built the first time Evaluate is called.
Evaluate will return an error if the River block cannot be evaluated or if decoding to arguments fails.
func (*ConfigNode) LoggingArgs ¶ added in v0.29.0
func (cn *ConfigNode) LoggingArgs() logging.Options
LoggingArgs returns the arguments used to configure the logger.
func (*ConfigNode) NodeID ¶ added in v0.29.0
func (cn *ConfigNode) NodeID() string
NodeID implements dag.Node and returns the unique ID for the config node.
func (*ConfigNode) TracingArgs ¶ added in v0.29.0
func (cn *ConfigNode) TracingArgs() tracing.Options
TracingArgs returns the arguments used to configure the tracer.
type Loader ¶
type Loader struct {
// contains filtered or unexported fields
}
The Loader builds and evaluates ComponentNodes from River blocks.
func NewLoader ¶
func NewLoader(globals ComponentGlobals) *Loader
NewLoader creates a new Loader. Components built by the Loader will be built with co for their options.
func (*Loader) Apply ¶
func (l *Loader) Apply(parentScope *vm.Scope, blocks []*ast.BlockStmt, configBlocks []*ast.BlockStmt) diag.Diagnostics
Apply loads a new set of components into the Loader. Apply will drop any previously loaded component which is not described in the set of River blocks.
Apply will reuse existing components if there is an existing component which matches the component ID specified by any of the provided River blocks. Reused components will be updated to point at the new River block.
Apply will perform an evaluation of all loaded components before returning. The provided parentContext can be used to provide global variables and functions to components. A child context will be constructed from the parent to expose values of other components.
func (*Loader) Components ¶
func (l *Loader) Components() []*ComponentNode
Components returns the current set of loaded components.
func (*Loader) EvaluateDependencies ¶
func (l *Loader) EvaluateDependencies(parentScope *vm.Scope, c *ComponentNode)
EvaluateDependencies re-evaluates components which depend directly or indirectly on c. EvaluateDependencies should be called whenever a component updates its exports.
The provided parentContext can be used to provide global variables and functions to components. A child context will be constructed from the parent to expose values of other components.
func (*Loader) Graph ¶
func (l *Loader) Graph() *dag.Graph
Graph returns a copy of the DAG managed by the Loader.
func (*Loader) OriginalGraph ¶ added in v0.28.0
func (l *Loader) OriginalGraph() *dag.Graph
OriginalGraph returns a copy of the graph before Reduce was called. This can be used if you want to show a UI of the original graph before the reduce function was called.
type Queue ¶
type Queue struct {
// contains filtered or unexported fields
}
Queue is an unordered queue of components.
Queue is intended for tracking components that have updated their Exports for later reevaluation.
func (*Queue) Chan ¶
func (q *Queue) Chan() <-chan struct{}
Chan returns a channel which is written to when the queue is non-empty.
func (*Queue) Enqueue ¶
func (q *Queue) Enqueue(c *ComponentNode)
Enqueue inserts a new component into the Queue. Enqueue is a no-op if the component is already in the Queue.
func (*Queue) TryDequeue ¶
func (q *Queue) TryDequeue() *ComponentNode
TryDequeue dequeues a randomly queued component. TryDequeue will return nil if the queue is empty.
type Reference ¶
type Reference struct {
Target *ComponentNode // Component being referenced
// Traversal describes which nested field relative to Target is being
// accessed.
Traversal Traversal
}
Reference describes an River expression reference to a ComponentNode.
func ComponentReferences ¶
func ComponentReferences(cn dag.Node, g *dag.Graph) ([]Reference, diag.Diagnostics)
ComponentReferences returns the list of references a component is making to other components.
type RunnableNode ¶
type RunnableNode interface {
NodeID() string
Run(ctx context.Context) error
}
RunnableNode is any dag.Node which can also be ran.
type Scheduler ¶
type Scheduler struct {
// contains filtered or unexported fields
}
Scheduler runs components.
func NewScheduler ¶
func NewScheduler() *Scheduler
NewScheduler creates a new Scheduler. Call Synchronize to manage the set of components which are running.
Call Close to stop the Scheduler and all running components.
func (*Scheduler) Close ¶
func (s *Scheduler) Close() error
Close stops the Scheduler and returns after all running goroutines have exited.
func (*Scheduler) Synchronize ¶
func (s *Scheduler) Synchronize(rr []RunnableNode) error
Synchronize synchronizes the running components to those defined by rr.
New RunnableNodes will be launched as new goroutines. RunnableNodes already managed by Scheduler will be kept running, while running RunnableNodes that are not in rr will be shut down and removed.
Existing components will be restarted if they stopped since the previous call to Synchronize.
type Traversal ¶ added in v0.27.0
type Traversal []*ast.Ident
Traversal describes accessing a sequence of fields relative to a component. Traversal only include uninterrupted sequences of field accessors; for an expression "component.field_a.field_b.field_c[0].inner_field", the Traversal will be (field_a, field_b, field_c).
Source Files