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import * as api from './apiServer.js';
import * as md from './markdown.js';
class PostToChannel {
constructor(channel, body) {
this.channel = channel;
this.body = body;
this.renderedBody = md.render(body);
}
async send() {
return await api.retry(() => api.postToChannel(this.channel, this.body));
}
}
class DeleteMessage {
constructor(messageId) {
this.messageId = messageId;
}
async send() {
return await api.retry(() => api.deleteMessage(this.messageId));
}
}
class CreateChannel {
constructor(name) {
this.name = name;
}
async send() {
return await api.retry(() => api.createChannel(this.name));
}
}
export class Outbox {
pending = $state([]);
static empty() {
return new Outbox([]);
}
constructor(pending) {
this.pending = pending;
}
enqueue(operation) {
this.pending.push(operation);
this.start();
}
createChannel(name) {
this.enqueue(new CreateChannel(name));
}
postToChannel(channel, body) {
this.enqueue(new PostToChannel(channel, body));
}
deleteMessage(messageId) {
this.enqueue(new DeleteMessage(messageId));
}
start() {
if (this.sending) {
return;
}
// This is a promise transform primarily to keep the management of `this.sending` in one place,
// rather than spreading it across multiple methods.
this.sending = this.drain().finally(() => {
this.sending = null;
// If we encounter an exception processing the pending queue, it may have an operation left
// in it. If so, start over. The exception will still propagate out (though since nothing
// ever awaits the promise from this.sending, it'll ultimately leak out to the browser
// anyways).
if (this.pending.length > 0) {
this.start();
}
});
}
async drain() {
while (this.pending.length > 0) {
const operation = this.pending[0];
try {
await operation.send();
} finally {
this.pending.shift();
}
}
}
}
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