fluid.model.transformWithRules
- Anastasia Cheetham
This functionality is Sneak Peek status. This means that the APIs may change. We welcome your feedback, ideas, and code, but please use caution if you use this new functionality.
This page is still a rough draft.
fluid.model.transformWithRules(model, rules)
Transforms a model based on a specified expansion rules objects.
fluid.model.transformWithRules(model, rules);
File name: ModelTransformations.js
Parameters
model |
(Object) the model to transform |
rules |
(Object) a rules object containing instructions on how to transform the model (see below for more information) |
Return Value
| Object | the transformed model |
See Also
Rules
Rules objects take the form of:
{
"target.path": "value.el.path" || {
expander: {
type: "expander.function.path",
...
}
}
}
Transformation Expanders
The Framework currently provides the following expanders that can be used as part of a model transformation.
fluid.model.transform.valuefluid.model.transform.arrayValuefluid.model.transform.firstValuefluid.model.transform.merge
Each of these is described below.
fluid.model.transform.value
This extracts and/or the value of a given path, and can be used for the following purposes:
To rename a property:
Start:
var source = {
cat: "meow",
...
}
>>
Rule to rename "cat" to "feline":
var rules = {
feline: {
expander: {
type: "fluid.model.transform.value",
// specify only the path to transform
path: "cat"
}
},
....
}
>>
Result:
{
feline: "meow",
...
}
To set a default value:
Start:
var source = {
gerbil: undefined,
// or if "gerbil" doesn't exist
...
}
>>
Rule to set default value of "gerbil":
var rules = {
gerbil: {
expander: {
type: "fluid.model.transform.value",
// specify path and default value
path: "gerbil",
value: "squeek"
}
},
....
}
>>
Result:
{
gerbil: "squeek",
...
}
Note that if "gerbil" has a value initially, it will be unaffected.
To specify a literal value:
Start:
var source = {
// no mention of kangaroos
...
}
>>
Rule to set a value for "kangaroo":
var rules = {
kangaroo: {
expander: {
type: "fluid.model.transform.value",
// specify only a value
value: "boingg"
}
},
....
}
>>
Result:
{
kangaroo: "boingg",
...
}
To change the structure/nesting:
Start:
var source = {
goat: false,
sheep: [
"baaa",
"wooooool"
],
...
}
>>
Rule to change the nesting:
var rules = {
"farm.goat": {
expander: {
type: "fluid.model.transform.value",
path: "goat"
}
},
"farm.sheep": {
expander: {
type: "fluid.model.transform.value",
path: "sheep"
}
}
....
}
>>
Result:
{
farm: {
goat: false,
sheep: [
"baaa",
"wooooool"
]
},
...
}
fluid.model.transform.arrayValue
The arrayValue expander will transform a value into an aray. If the value is already an array, the expander will have no effect.
For example:
Start:
var source = {
cat: "meow",
sheep: [
"baaa",
"wooooool"
],
...
}
>>
Rule to convert to arrays:
var rules = {
cat: {
expander: {
type: "fluid.model.transform.arrayValue",
path: "cat"
}
},
sheep: {
expander: {
type: "fluid.model.transform.arrayValue",
path: "sheep"
}
}
....
}
>>
Result:
{
cat: ["meow"],
sheep: [
"baaa",
"wooooool"
],
...
}
Note that the value of cat is now an array, but the value of sheep is unaffected.
fluid.model.transform.firstValue
fluid.model.transform.merge
Example
In this example, description here...