lightspeed/diff

Patch model and codec for rendered updates.

Types

DecodeError

Decode errors for patch streams.

pub type DecodeError {
  EmptyPayload
  UnknownPayloadTag(String)
  BadFieldCount(stage: String, expected: Int, actual: Int)
  InvalidInteger(String)
  UnsupportedVersion(Int)
  MissingDictionaryEntry(Int)
  MalformedOperation(String)
  InvalidEscapeSequence
}

Constructors

```
EmptyPayload
```
```
UnknownPayloadTag(String)
```

BadFieldCount(stage: String, expected: Int, actual: Int)

```
InvalidInteger(String)
```
```
UnsupportedVersion(Int)
```
```
MissingDictionaryEntry(Int)
```
```
MalformedOperation(String)
```
```
InvalidEscapeSequence
```

DynamicSlot

Dynamic text values injected into static markup by slot name.

pub type DynamicSlot {
  DynamicSlot(name: String, value: String)
}

Constructors

DynamicSlot(name: String, value: String)

KeyedNode

Keyed nodes used for stable collection updates.

pub type KeyedNode {
  KeyedNode(key: String, html: String)
}

Constructors

```
KeyedNode(key: String, html: String)
```

Patch

Patch model.

pub type Patch {
  Replace(target: String, html: String)
  Append(target: String, html: String)
  Prepend(target: String, html: String)
  Remove(target: String)
  ReplaceSegments(
    target: String,
    fingerprint: String,
    static_html: String,
    dynamic_slots: List(DynamicSlot),
  )
  UpdateSegments(
    target: String,
    fingerprint: String,
    dynamic_slots: List(DynamicSlot),
  )
  UpsertKeyed(target: String, key: String, html: String)
  RemoveKeyed(target: String, key: String)
  ReorderKeyed(target: String, keys: List(String))
}

Constructors

```
Replace(target: String, html: String)
```
```
Append(target: String, html: String)
```
```
Prepend(target: String, html: String)
```
```
Remove(target: String)
```

ReplaceSegments(
  target: String,
  fingerprint: String,
  static_html: String,
  dynamic_slots: List(DynamicSlot),
)

UpdateSegments(
  target: String,
  fingerprint: String,
  dynamic_slots: List(DynamicSlot),
)

UpsertKeyed(target: String, key: String, html: String)

RemoveKeyed(target: String, key: String)

ReorderKeyed(target: String, keys: List(String))

Values

carries_html

pub fn carries_html(patch: Patch) -> Bool

True when a patch carries HTML content.

decode

pub fn decode(payload: String) -> Result(Patch, DecodeError)

Decode one patch from a versioned compressed stream.

decode_error_to_string

pub fn decode_error_to_string(error: DecodeError) -> String

Stable error labels for logs and adapter failures.

decode_stream

pub fn decode_stream(
  payload: String,
) -> Result(List(Patch), DecodeError)

Decode a patch stream.

encode

pub fn encode(patch: Patch) -> String

Encode one patch into a versioned compressed stream.

encode_stream

pub fn encode_stream(patches: List(Patch)) -> String

Encode a patch stream with dictionary compression.

keyed_node

pub fn keyed_node(key: String, html: String) -> KeyedNode

Build one keyed node.

keyed_patch_plan

pub fn keyed_patch_plan(
  target: String,
  previous: List(KeyedNode),
  current: List(KeyedNode),
) -> List(Patch)

Build a keyed update plan from previous and current collections.

operation

pub fn operation(patch: Patch) -> String

Return the patch operation name.

patch_stream_version

pub const patch_stream_version: Int

slot

pub fn slot(name: String, value: String) -> DynamicSlot

Build one dynamic slot value.

target

pub fn target(patch: Patch) -> String

Return the target selector or id for a patch.