package core

import "github.com/purpleidea/mgmt/lang/core"

Package core contains core functions and other related facilities which are used in programs.

Index

Constants 

const (
	// CollectFuncName is the name this function is registered as. This
	// starts with an underscore so that it cannot be used from the lexer.
	CollectFuncName = funcs.CollectFuncName
)
const (
	// ConcatFuncName is the name this function is registered as.
	ConcatFuncName = funcs.ConcatFuncName
)
const (
	// ContainsFuncName is the name this function is registered as.
	ContainsFuncName = funcs.ContainsFuncName
)
const (
	// HistoryFuncName is the name this function is registered as.
	// TODO: move this into a separate package
	HistoryFuncName = "history"
)
const (
	// ListLookupDefaultFuncName is the name this function is registered as.
	ListLookupDefaultFuncName = "list_lookup_default"
)
const (
	// ListLookupFuncName is the name this function is registered as.
	ListLookupFuncName = "list_lookup"
)
const (
	// LookupDefaultFuncName is the name this function is registered as.
	// This starts with an underscore so that it cannot be used from the
	// lexer.
	LookupDefaultFuncName = funcs.LookupDefaultFuncName
)
const (
	// LookupFuncName is the name this function is registered as.
	// This starts with an underscore so that it cannot be used from the
	// lexer.
	LookupFuncName = funcs.LookupFuncName
)
const (
	// MapLookupDefaultFuncName is the name this function is registered as.
	MapLookupDefaultFuncName = "map_lookup_default"
)
const (
	// MapLookupFuncName is the name this function is registered as.
	MapLookupFuncName = "map_lookup"
)
const (
	// Random1FuncName is the name this function is registered as.
	Random1FuncName = "random1"
)
const (
	// StructLookupFuncName is the name this function is registered as. This
	// starts with an underscore so that it cannot be used from the lexer.
	StructLookupFuncName = funcs.StructLookupFuncName
)
const (
	// StructLookupOptionalFuncName is the name this function is registered
	// as. This starts with an underscore so that it cannot be used from the
	// lexer.
	StructLookupOptionalFuncName = funcs.StructLookupOptionalFuncName
)

Functions

func Asset 

func Asset(name string) ([]byte, error)

Asset returns the contents of an embedded .mcl file.

func AssetNames 

func AssetNames() ([]string, error)

AssetNames returns a flattened list of embedded .mcl file paths.

func Concat 

func Concat(ctx context.Context, input []types.Value) (types.Value, error)

Concat concatenates two strings together.

func Contains 

func Contains(ctx context.Context, input []types.Value) (types.Value, error)

Contains checks if a needle exists in a haystack, which is a list.

func Len 

func Len(ctx context.Context, input []types.Value) (types.Value, error)

Len returns the number of elements in a list or the number of key pairs in a map. It can operate on either of these types.

func ListLookup 

func ListLookup(ctx context.Context, input []types.Value) (types.Value, error)

ListLookup returns the value corresponding to the input index in the list.

func ListLookupDefault 

func ListLookupDefault(ctx context.Context, input []types.Value) (types.Value, error)

ListLookupDefault returns the value corresponding to the input index in the list. If the value is not present, it returns the default value supplied.

func MapLookup 

func MapLookup(ctx context.Context, input []types.Value) (types.Value, error)

MapLookup returns the value corresponding to the input key in the map.

func MapLookupDefault 

func MapLookupDefault(ctx context.Context, input []types.Value) (types.Value, error)

MapLookupDefault returns the value corresponding to the input key in the map. If the value is not present, it returns the default value supplied.

func Panic 

func Panic(ctx context.Context, input []types.Value) (types.Value, error)

Panic returns an error when it receives a non-empty string or a true boolean. The error should cause the function engine to shutdown. If there's no error, it returns false.

Types

type CollectFunc 

type CollectFunc struct {
	// Type is the type of the second arg that we receive. (When known.)
	Type *types.Type
	// contains filtered or unexported fields
}

CollectFunc is a special internal function which gets given information about incoming resource collection data. For example, to collect, that "pseudo resource" will need to know what resource "kind" it's collecting, the names of those resources, and the corresponding hostnames that they are getting the data from. With that three-tuple of data, it can pull all of that from etcd and pass it into a hidden resource body field so that the collect "pseudo resource" can use it to build the exported resource!

The "kind" comes in as the first arg. The second arg (in its complex form) is []struct{name str; host str} is what the end user is _asking_ this function for. TODO: We could have a second version of this collect function which takes a single arg which receives []struct{kind str; name str; host str} which would let us write a truly dynamic collector. It's unlikely we want to allow this in most cases because it lets you play type games since the field name in one resource kind might be a different type in another.

func (*CollectFunc) ArgGen 

func (obj *CollectFunc) ArgGen(index int) (string, error)

ArgGen returns the Nth arg name for this function.

func (*CollectFunc) Build 

func (obj *CollectFunc) Build(typ *types.Type) (*types.Type, error)

Build is run to turn the polymorphic, undetermined function, into the specific statically typed version. It is usually run after Unify completes, and must be run before Info() and any of the other Func interface methods are used. This function is idempotent, as long as the arg isn't changed between runs.

func (*CollectFunc) Call 

func (obj *CollectFunc) Call(ctx context.Context, args []types.Value) (types.Value, error)

Call this function with the input args and return the value if it is possible to do so at this time. This was previously getValue which gets the value we're looking for.

func (*CollectFunc) Copy 

func (obj *CollectFunc) Copy() interfaces.Func

Copy is implemented so that the obj.Type value is not lost if we copy this function. That value is learned during FuncInfer, and previously would have been lost by the time we used it in Build.

func (*CollectFunc) FuncInfer 

func (obj *CollectFunc) FuncInfer(partialType *types.Type, partialValues []types.Value) (*types.Type, []*interfaces.UnificationInvariant, error)

FuncInfer takes partial type and value information from the call site of this function so that it can build an appropriate type signature for it. The type signature may include unification variables.

func (*CollectFunc) Info 

func (obj *CollectFunc) Info() *interfaces.Info

Info returns some static info about itself. Build must be called before this will return correct data.

func (*CollectFunc) Init 

func (obj *CollectFunc) Init(init *interfaces.Init) error

Init runs some startup code for this function.

func (*CollectFunc) Stream 

func (obj *CollectFunc) Stream(ctx context.Context) error

Stream returns the changing values that this func has over time.

func (*CollectFunc) String 

func (obj *CollectFunc) String() string

String returns a simple name for this function. This is needed so this struct can satisfy the pgraph.Vertex interface.

func (*CollectFunc) Validate 

func (obj *CollectFunc) Validate() error

Validate tells us if the input struct takes a valid form.

type HistoryFunc 

type HistoryFunc struct {
	Type *types.Type // type of input value (same as output type)
	// contains filtered or unexported fields
}

HistoryFunc is special function which returns the Nth oldest value seen. It must store up incoming values until it gets enough to return the desired one. A restart of the program, will expunge the stored state. This obviously takes more memory, the further back you wish to index. A change in the index var is generally not useful, but it is permitted. Moving it to a smaller value will cause older index values to be expunged. If this is undesirable, a max count could be added. This was not implemented with efficiency in mind. Since some functions might not send out un-changed values, it might also make sense to implement a *time* based hysteresis, since this only looks at the last N changed values. A time based hysteresis would tick every precision-width, and store whatever the latest value at that time is.

func (*HistoryFunc) ArgGen 

func (obj *HistoryFunc) ArgGen(index int) (string, error)

ArgGen returns the Nth arg name for this function.

func (*HistoryFunc) Build 

func (obj *HistoryFunc) Build(typ *types.Type) (*types.Type, error)

Build takes the now known function signature and stores it so that this function can appear to be static. That type is used to build our function statically.

func (*HistoryFunc) Info 

func (obj *HistoryFunc) Info() *interfaces.Info

Info returns some static info about itself.

func (*HistoryFunc) Init 

func (obj *HistoryFunc) Init(init *interfaces.Init) error

Init runs some startup code for this function.

func (*HistoryFunc) Stream 

func (obj *HistoryFunc) Stream(ctx context.Context) error

Stream returns the changing values that this func has over time.

func (*HistoryFunc) String 

func (obj *HistoryFunc) String() string

String returns a simple name for this function. This is needed so this struct can satisfy the pgraph.Vertex interface.

func (*HistoryFunc) Validate 

func (obj *HistoryFunc) Validate() error

Validate makes sure we've built our struct properly. It is usually unused for normal functions that users can use directly.

type LookupDefaultFunc 

type LookupDefaultFunc struct {
	Type *types.Type // Kind == List OR Map, that is used as the list/map we lookup in
	// contains filtered or unexported fields
}

LookupDefaultFunc is a list index or map key lookup function. It does both because the current syntax in the parser is identical, so it's convenient to mix the two together. This calls out to some of the code in the ListLookupDefaultFunc and MapLookupDefaultFunc implementations. If the index or key for this input doesn't exist, then it will return the default value you specified for this function. TODO: Eventually we will deprecate this function when the function engine can support passing a value for erroring functions. (Bad index could be an err!)

func (*LookupDefaultFunc) ArgGen 

func (obj *LookupDefaultFunc) ArgGen(index int) (string, error)

ArgGen returns the Nth arg name for this function.

func (*LookupDefaultFunc) Build 

func (obj *LookupDefaultFunc) Build(typ *types.Type) (*types.Type, error)

Build is run to turn the polymorphic, undetermined function, into the specific statically typed version. It is usually run after Unify completes, and must be run before Info() and any of the other Func interface methods are used. This function is idempotent, as long as the arg isn't changed between runs.

func (*LookupDefaultFunc) Call 

func (obj *LookupDefaultFunc) Call(ctx context.Context, args []types.Value) (types.Value, error)

Call returns the result of this function.

func (*LookupDefaultFunc) Info 

func (obj *LookupDefaultFunc) Info() *interfaces.Info

Info returns some static info about itself. Build must be called before this will return correct data.

func (*LookupDefaultFunc) Init 

func (obj *LookupDefaultFunc) Init(init *interfaces.Init) error

Init runs some startup code for this function.

func (*LookupDefaultFunc) Stream 

func (obj *LookupDefaultFunc) Stream(ctx context.Context) error

Stream returns the changing values that this func has over time.

func (*LookupDefaultFunc) String 

func (obj *LookupDefaultFunc) String() string

String returns a simple name for this function. This is needed so this struct can satisfy the pgraph.Vertex interface.

func (*LookupDefaultFunc) Validate 

func (obj *LookupDefaultFunc) Validate() error

Validate tells us if the input struct takes a valid form.

type LookupFunc 

type LookupFunc struct {
	Type *types.Type // Kind == List OR Map, that is used as the list/map we lookup in
	// contains filtered or unexported fields
}

LookupFunc is a list index or map key lookup function. It does both because the current syntax in the parser is identical, so it's convenient to mix the two together. This calls out to some of the code in the ListLookupFunc and MapLookupFunc implementations. If the index or key for this input doesn't exist, then it will return the zero value for that type. TODO: Eventually we will deprecate this function when the function engine can support passing a value for erroring functions. (Bad index could be an err!)

func (*LookupFunc) ArgGen 

func (obj *LookupFunc) ArgGen(index int) (string, error)

ArgGen returns the Nth arg name for this function.

func (*LookupFunc) Build 

func (obj *LookupFunc) Build(typ *types.Type) (*types.Type, error)

Build is run to turn the polymorphic, undetermined function, into the specific statically typed version. It is usually run after Unify completes, and must be run before Info() and any of the other Func interface methods are used. This function is idempotent, as long as the arg isn't changed between runs.

func (*LookupFunc) Call 

func (obj *LookupFunc) Call(ctx context.Context, args []types.Value) (types.Value, error)

Call returns the result of this function.

func (*LookupFunc) FuncInfer 

func (obj *LookupFunc) FuncInfer(partialType *types.Type, partialValues []types.Value) (*types.Type, []*interfaces.UnificationInvariant, error)

FuncInfer takes partial type and value information from the call site of this function so that it can build an appropriate type signature for it. The type signature may include unification variables.

func (*LookupFunc) Info 

func (obj *LookupFunc) Info() *interfaces.Info

Info returns some static info about itself. Build must be called before this will return correct data.

func (*LookupFunc) Init 

func (obj *LookupFunc) Init(init *interfaces.Init) error

Init runs some startup code for this function.

func (*LookupFunc) Stream 

func (obj *LookupFunc) Stream(ctx context.Context) error

Stream returns the changing values that this func has over time.

func (*LookupFunc) String 

func (obj *LookupFunc) String() string

String returns a simple name for this function. This is needed so this struct can satisfy the pgraph.Vertex interface.

func (*LookupFunc) Validate 

func (obj *LookupFunc) Validate() error

Validate tells us if the input struct takes a valid form.

type Random1Func 

type Random1Func struct {
	// contains filtered or unexported fields
}

Random1Func returns one random string of a certain length. XXX: return a stream instead, and combine this with a first(?) function which takes the first value and then puts backpressure on the stream. This should notify parent functions somehow that their values are no longer required so that they can shutdown if possible. Maybe it should be returning a stream of floats [0,1] as well, which someone can later map to the alphabet that they want. Should random() take an interval to know how often to spit out values? It could also just do it once per second, and we could filter for less. If we want something high precision, we could add that in the future... We could name that "random" and this one can be "random1" until we deprecate it.

func (*Random1Func) ArgGen 

func (obj *Random1Func) ArgGen(index int) (string, error)

ArgGen returns the Nth arg name for this function.

func (*Random1Func) Info 

func (obj *Random1Func) Info() *interfaces.Info

Info returns some static info about itself.

func (*Random1Func) Init 

func (obj *Random1Func) Init(init *interfaces.Init) error

Init runs some startup code for this function.

func (*Random1Func) Stream 

func (obj *Random1Func) Stream(ctx context.Context) error

Stream returns the single value that was generated and then closes.

func (*Random1Func) String 

func (obj *Random1Func) String() string

String returns a simple name for this function. This is needed so this struct can satisfy the pgraph.Vertex interface.

func (*Random1Func) Validate 

func (obj *Random1Func) Validate() error

Validate makes sure we've built our struct properly. It is usually unused for normal functions that users can use directly.

type StructLookupFunc 

type StructLookupFunc struct {
	Type *types.Type // Kind == Struct, that is used as the struct we lookup
	Out  *types.Type // type of field we're extracting
	// contains filtered or unexported fields
}

StructLookupFunc is a struct field lookup function.

func (*StructLookupFunc) ArgGen 

func (obj *StructLookupFunc) ArgGen(index int) (string, error)

ArgGen returns the Nth arg name for this function.

func (*StructLookupFunc) Build 

func (obj *StructLookupFunc) Build(typ *types.Type) (*types.Type, error)

Build is run to turn the polymorphic, undetermined function, into the specific statically typed version. It is usually run after Unify completes, and must be run before Info() and any of the other Func interface methods are used. This function is idempotent, as long as the arg isn't changed between runs.

func (*StructLookupFunc) Call 

func (obj *StructLookupFunc) Call(ctx context.Context, args []types.Value) (types.Value, error)

Call returns the result of this function.

func (*StructLookupFunc) Copy 

func (obj *StructLookupFunc) Copy() interfaces.Func

Copy is implemented so that the obj.field value is not lost if we copy this function. That value is learned during FuncInfer, and previously would have been lost by the time we used it in Build.

func (*StructLookupFunc) FuncInfer 

func (obj *StructLookupFunc) FuncInfer(partialType *types.Type, partialValues []types.Value) (*types.Type, []*interfaces.UnificationInvariant, error)

FuncInfer takes partial type and value information from the call site of this function so that it can build an appropriate type signature for it. The type signature may include unification variables.

func (*StructLookupFunc) Info 

func (obj *StructLookupFunc) Info() *interfaces.Info

Info returns some static info about itself. Build must be called before this will return correct data.

func (*StructLookupFunc) Init 

func (obj *StructLookupFunc) Init(init *interfaces.Init) error

Init runs some startup code for this function.

func (*StructLookupFunc) Stream 

func (obj *StructLookupFunc) Stream(ctx context.Context) error

Stream returns the changing values that this func has over time.

func (*StructLookupFunc) String 

func (obj *StructLookupFunc) String() string

String returns a simple name for this function. This is needed so this struct can satisfy the pgraph.Vertex interface.

func (*StructLookupFunc) Validate 

func (obj *StructLookupFunc) Validate() error

Validate tells us if the input struct takes a valid form.

type StructLookupOptionalFunc 

type StructLookupOptionalFunc struct {
	Type *types.Type // Kind == Struct, that is used as the struct we lookup
	Out  *types.Type // type of field we're extracting (also the type of optional)
	// contains filtered or unexported fields
}

StructLookupOptionalFunc is a struct field lookup function. It does a special trick in that it will unify on a struct that doesn't have the specified field in it, but in that case, it will always return the optional value. This is a bit different from the "default" mechanism that is used by list and map lookup functions.

func (*StructLookupOptionalFunc) ArgGen 

func (obj *StructLookupOptionalFunc) ArgGen(index int) (string, error)

ArgGen returns the Nth arg name for this function.

func (*StructLookupOptionalFunc) Build 

func (obj *StructLookupOptionalFunc) Build(typ *types.Type) (*types.Type, error)

Build is run to turn the polymorphic, undetermined function, into the specific statically typed version. It is usually run after Unify completes, and must be run before Info() and any of the other Func interface methods are used. This function is idempotent, as long as the arg isn't changed between runs.

func (*StructLookupOptionalFunc) Call 

func (obj *StructLookupOptionalFunc) Call(ctx context.Context, args []types.Value) (types.Value, error)

Call returns the result of this function.

func (*StructLookupOptionalFunc) Copy 

func (obj *StructLookupOptionalFunc) Copy() interfaces.Func

Copy is implemented so that the obj.field value is not lost if we copy this function. That value is learned during FuncInfer, and previously would have been lost by the time we used it in Build.

func (*StructLookupOptionalFunc) FuncInfer 

func (obj *StructLookupOptionalFunc) FuncInfer(partialType *types.Type, partialValues []types.Value) (*types.Type, []*interfaces.UnificationInvariant, error)

FuncInfer takes partial type and value information from the call site of this function so that it can build an appropriate type signature for it. The type signature may include unification variables.

func (*StructLookupOptionalFunc) Info 

func (obj *StructLookupOptionalFunc) Info() *interfaces.Info

Info returns some static info about itself. Build must be called before this will return correct data.

func (*StructLookupOptionalFunc) Init 

func (obj *StructLookupOptionalFunc) Init(init *interfaces.Init) error

Init runs some startup code for this function.

func (*StructLookupOptionalFunc) Stream 

func (obj *StructLookupOptionalFunc) Stream(ctx context.Context) error

Stream returns the changing values that this func has over time.

func (*StructLookupOptionalFunc) String 

func (obj *StructLookupOptionalFunc) String() string

String returns a simple name for this function. This is needed so this struct can satisfy the pgraph.Vertex interface.

func (*StructLookupOptionalFunc) Validate 

func (obj *StructLookupOptionalFunc) Validate() error

Validate tells us if the input struct takes a valid form.

Source Files

collect.go concat.go contains.go core.go history.go len.go list_lookup.go list_lookup_default.go lookup.go lookup_default.go map_lookup.go map_lookup_default.go panic.go random1.go struct_lookup.go struct_lookup_optional.go

Directories

PathSynopsis
lang/core/convert
lang/core/datetime
lang/core/deploy
lang/core/embedded
lang/core/embedded/provisioner
lang/core/example
lang/core/example/nested
lang/core/fmt
lang/core/golang
lang/core/iter
lang/core/list
lang/core/local
lang/core/map
lang/core/math
lang/core/net
lang/core/os
lang/core/regexp
lang/core/strings
lang/core/sys
lang/core/test
lang/core/util
lang/core/value
lang/core/world
lang/core/world/collect
Version
v0.0.0-20250405210053-9c1c587f7bc2 (latest)
Published
Apr 5, 2025
Platform
linux/amd64
Imports
36 packages
Last checked
2 days ago –

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