Enum ItemCommand 

pub enum ItemCommand {
    Add,
    Update,
    Delete,
    Unrecognized(String),
}

What a COMMAND-mode update did to the row named by its key.

In COMMAND mode the subscription is a dynamic table: “each real-time update may add a new row, delete an existing row or change the content of a specific row” [docs/spec/04-notifications.md §3.3]. Which of the three happened is carried in the field whose position SUBCMD reported [docs/spec/04-notifications.md §3.2], and the row it applies to is named by the value of the key field.

SPEC-AMBIGUITY (command-literals): the specification names the commands ADD, DELETE and UPDATE but “nowhere states the literal wire values carried in the command field of a U notification, nor their casing” [docs/spec/04-notifications.md §3.3]. This crate matches the three names case-insensitively — the most permissive reading that cannot admit a fourth command by accident — and preserves anything else as ItemCommand::Unrecognized rather than rejecting the update, so a server that grows a command cannot break a client that does not know it.

Variants

Add

A row entered the table. Its fields are the ones this update carries.

Update

An existing row changed. The fields this update did not carry keep the values they already had.

Delete

A row left the table. The caller should drop its own representation of the row named by ItemUpdate::key.

Note what this does not mean for the state this crate keeps: see the DELETE discussion on ItemUpdate::key.

Unrecognized(String)

The command field held something else. The value is preserved verbatim.

Tuple Fields

0: String

The command exactly as the server sent it, after decoding.

Implementations

impl ItemCommand

pub fn as_str(&self) -> &str

The command as an uppercase name, or the preserved literal for ItemCommand::Unrecognized.

Trait Implementations

impl Clone for ItemCommand

fn clone(&self) -> ItemCommand

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ItemCommand

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for ItemCommand

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for ItemCommand

impl Hash for ItemCommand

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for ItemCommand

fn eq(&self, other: &ItemCommand) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for ItemCommand