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Merge pull request #1232 from influxdata/flux-0.74 

Flux 0.74
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Scott Anderson 2020-07-22 13:14:33 -06:00 committed by GitHub
parent 326864e15b 20cc3d9c91
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81
content/v2.0/reference/flux/language/statements.md
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@ -79,84 +79,3 @@ ExpressionStatement = Expression .
f()
a
```
## Named types
A named type can be created using a type assignment statement.
A named type is equivalent to the type it describes and may be used interchangeably.
```js
TypeAssignment = "type" identifier "=" TypeExpression .
TypeExpression = identifier
| TypeParameter
| ObjectType
| ArrayType
| GeneratorType
| FunctionType .
TypeParameter = "'" identifier .
ObjectType = "{" PropertyTypeList [";" ObjectUpperBound ] "}" .
ObjectUpperBound = "any" | PropertyTypeList .
PropertyTypeList = PropertyType [ "," PropertyType ] .
PropertyType = identifier ":" TypeExpression
| string_lit ":" TypeExpression .
ArrayType = "[]" TypeExpression .
GeneratorType = "[...]" TypeExpression .
FunctionType = ParameterTypeList "->" TypeExpression
ParameterTypeList = "(" [ ParameterType { "," ParameterType } ] ")" .
ParameterType = identifier ":" [ pipe_receive_lit ] TypeExpression .
```
Named types are a separate namespace from values.
It is possible for a value and a type to have the same identifier.
The following named types are built-in.
```js
bool // boolean
int // integer
uint // unsigned integer
float // floating point number
duration // duration of time
time // time
string // utf-8 encoded string
regexp // regular expression
bytes // sequence of byte values
type // a type that itself describes a type
```
When an object's upper bound is not specified, it is assumed to be equal to its lower bound.
Parameters to function types define whether the parameter is a pipe forward
parameter and whether the parameter has a default value.
The `<-` indicates the parameter is the pipe forward parameter.
###### Examples
```js
// alias the bool type
type boolean = bool
// define a person as an object type
type person = {
name: string,
age: int,
}
// Define addition on ints
type intAdd = (a: int, b: int) -> int
// Define polymorphic addition
type add = (a: 'a, b: 'a) -> 'a
// Define funcion with pipe parameter
type bar = (foo: <-string) -> string
// Define object type with an empty lower bound and an explicit upper bound
type address = {
;
street: string,
city: string,
state: string,
country: string,
province: string,
zip: int,
}
```

24
content/v2.0/reference/flux/language/system-built-ins.md
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@ -12,15 +12,35 @@ menu:
weight: 206
---
Flux contains many preassigned values. These preassigned values are defined in the source files for the various built-in packages.
When a built-in value is not expressible in Flux, its value may be defined by the hosting environment.
All such values must have a corresponding builtin statement to declare the existence and type of the built-in value.
```js
BuiltinStatement = "builtin" identifier ":" TypeExpression .
BuiltinStatement = "builtin" identifer ":" TypeExpression .
TypeExpression = MonoType ["where" Constraints] .
MonoType = Tvar | Basic | Array | Record | Function .
Tvar = "A" … "Z" .
Basic = "int" | "uint" | "float" | "string" | "bool" | "time" | "duration" | "bytes" | "regexp" .
Array = "[" MonoType "]" .
Record = ( "{" [Properties] "}" ) | ( "{" Tvar "with" Properties "}" ) .
Function = "(" [Parameters] ")" "=>" MonoType .
Properties = Property { "," Property } .
Property = identifier ":" MonoType .
Parameters = Parameter { "," Parameter } .
Parameter = [ "<-" | "?" ] identifier ":" MonoType .
Constraints = Constraint { "," Constraint } .
Constraint = Tvar ":" Kinds .
Kinds = identifier { "+" identifier } .
```
##### Example
```js
builtin from : (bucket: string, bucketID: string) -> stream
builtin filter : (<-tables: [T], fn: (r: T) -> bool) -> [T]
```

49
content/v2.0/reference/flux/language/types.md
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@ -14,9 +14,10 @@ Any section that is not currently implemented is commented with a **[IMPL#XXX]**
**XXX** is an issue number tracking discussion and progress towards implementation.
{{% /note %}}
A _type_ defines the set of values and operations on those values.
Types are never explicitly declared as part of the syntax.
A **type** defines the set of values and operations on those values.
Types are never explicitly declared as part of the syntax except as part of a [builtin statement](#system-built-ins).
Types are always inferred from the usage of the value.
Type inference follows a Hindley-Milner style inference system.
## Union types
A union type defines a set of types.
@ -154,3 +155,47 @@ The generated values may be of any other type, but must all be the same type.
{{% note %}}
[IMPL#658](https://github.com/influxdata/platform/query/issues/658) Implement Generators types.
{{% /note %}}
#### Polymorphism
Flux types can be polymorphic, meaning that a type may take on many different types.
Flux supports let-polymorphism and structural polymorphism.
##### Let-polymorphism
Let-polymorphism is the concept that each time an identifier is referenced, it may take on a different type.
For example:
```js
add = (a,b) => a + b
add(a:1,b:2) // 3
add(a:1.5,b:2.0) // 3.5
```
The identifiers, `a` and `b`, in the body of the `add` function are used as both `int` and `float` types.
##### Structural polymorphism
Structural polymorphism is the concept that structures (objects in Flux) can be
used by the same function even if the structures themselves are different.
For example:
```js
john = {name:"John", lastName:"Smith"}
jane = {name:"Jane", age:44}
// John and Jane are objects with different types.
// We can still define a function that can operate on both objects safely.
// name returns the name of a person
name = (person) => person.name
name(person:john) // John
name(person:jane) // Jane
device = {id: 125325, lat: 15.6163, lon: 62.6623}
name(person:device) // Type error, "device" does not have a property name.
```
Objects of differing types can be used as the same type so long as they both contain the necessary properties.
Necessary properties are determined by the use of the object.
This form of polymorphism means that checks are performed during type inference and not during runtime.
Type errors are found and reported before runtime.

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content/v2.0/reference/flux/stdlib/contrib/discord/_index.md
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@ -2,7 +2,7 @@
title: Flux Discord package
list_title: Discord package
description: >
The Flux Discord package provides functions for sending data to Discord.
The Flux Discord package provides functions for sending messages to Discord.
Import the `contrib/chobbs/discord` package.
menu:
v2_0_ref:
@ -12,7 +12,7 @@ weight: 202
v2.0/tags: [functions, discord, package]
---
The Flux Discord package provides functions for sending data to Discord.
The Flux Discord package provides functions for sending messages to Discord.
Import the `contrib/chobbs/discord` package:
```js

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content/v2.0/reference/flux/stdlib/contrib/discord/endpoint.md Normal file
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@ -0,0 +1,99 @@
---
title: discord.endpoint() function
description: >
The `discord.endpoint()` function sends a single message to a Discord channel using
a [Discord webhook](https://support.discord.com/hc/en-us/articles/228383668-Intro-to-Webhooks&amp?page=3)
and data from table rows.
menu:
v2_0_ref:
name: discord.endpoint
parent: Discord
weight: 202
---
The `discord.endpoint()` function sends a single message to a Discord channel using
a [Discord webhook](https://support.discord.com/hc/en-us/articles/228383668-Intro-to-Webhooks&amp?page=3)
and data from table rows.
_**Function type:** Output_
```js
import "contrib/chobbs/discord"
discord.endpoint(
webhookToken: "mySuPerSecRetTokEn",
webhookID: "123456789",
username: "username",
avatar_url: "https://example.com/avatar_pic.jpg"
)
```
## Parameters
### webhookToken
Discord [webhook token](https://discord.com/developers/docs/resources/webhook).
_**Data type:** String_
### webhookID
Discord [webhook ID](https://discord.com/developers/docs/resources/webhook).
_**Data type:** String_
### username
Override the Discord webhook's default username.
_**Data type:** String_
### avatar_url
Override the Discord webhook's default avatar.
_**Data type:** String_
## Usage
`discord.endpoint` is a factory function that outputs another function.
The output function requires a `mapFn` parameter.
### mapFn
A function that builds the object used to generate the Discord webhook request.
Requires an `r` parameter.
_**Data type:** Function_
`mapFn` accepts a table row (`r`) and returns an object that must include the
following field:
- `content`
_For more information, see the [`discord.send() content` parameter](/v2.0/reference/flux/stdlib/contrib/discord/send/#content)._
## Examples
##### Send critical statuses to a Discord channel
```js
import "influxdata/influxdb/secrets"
import "contrib/chobbs/discord"
discordToken = secrets.get(key: "DISCORD_TOKEN")
endpoint = telegram.endpoint(
webhookToken: discordToken,
webhookID: "123456789",
username: "critBot"
)
crit_statuses = from(bucket: "example-bucket")
|> range(start: -1m)
|> filter(fn: (r) => r._measurement == "statuses" and status == "crit")
crit_statuses
|> endpoint(mapFn: (r) => ({
content: "The status is critical!",
})
)()
```
{{% note %}}
#### Package author and maintainer
**Github:** [@chobbs](https://github.com/chobbs)
**InfluxDB Slack:** [@craig](https://influxdata.com/slack)
{{% /note %}}

17
content/v2.0/reference/release-notes/flux.md
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@ -16,6 +16,23 @@ Though newer versions of Flux may be available, they will not be included with
InfluxDB until the next InfluxDB v2.0 release._
{{% /note %}}
## v0.74.0 [2020-07-21]
### Features
- Add `discord.endpoint()` function.
- Enhance the static table API.
- Update `mod.rs` with `parse_type_expression` and other supporting functions.
- Expose static table package and table diff functions.
- `Find_var_type()` API.
- Add `stringify` method for a table and a diff utility.
- Added range to end-to-end tests.
- Add types grammar to SPEC.
### Bug fixes
- Normalize Monotype.
---
## v0.73.0 [2020-07-13]
### Features