Blogging platform with advanced tools for arts and sciences.
Add support for Atom feeds
+109
+97
infra/api/src/index.ts
+97
infra/api/src/index.ts
···
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return { statusCode: 200, headers: { 'Content-Type': 'text/plain' }, body: result.Item.pubAtUri as string };
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}
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function escXml(s: string): string {
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return s.replace(/&/g, '&').replace(/</g, '<').replace(/>/g, '>').replace(/"/g, '"');
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}
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async function getPublicationFeed(rawPath: string): Promise<APIGatewayProxyResultV2> {
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if (!SITE_DOMAIN) {
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return { statusCode: 404, headers: { 'Content-Type': 'text/plain' }, body: 'Not found' };
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}
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const feedSuffix = '/feed.xml';
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const rawPubPath = rawPath.slice(0, rawPath.length - feedSuffix.length);
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const pubPath = decodeURIComponent(rawPubPath);
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const pubUrl = `https://${SITE_DOMAIN}${pubPath}`;
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const urlLookup = await ddb.send(new GetCommand({
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TableName: TABLE,
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Key: { PK: `url#${pubUrl}`, SK: 'info' },
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}));
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if (!urlLookup.Item?.pubAtUri) {
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return { statusCode: 404, headers: { 'Content-Type': 'text/plain' }, body: 'Not found' };
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}
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const pubAtUri = urlLookup.Item.pubAtUri as string;
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const atParts = pubAtUri.slice('at://'.length).split('/');
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const did = atParts[0];
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const pubRkey = atParts[2];
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const [pubResult, postsResult, authorHandle] = await Promise.all([
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ddb.send(new GetCommand({ TableName: TABLE, Key: { PK: `u#${did}#pub`, SK: `pub#${pubRkey}` } })),
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ddb.send(new QueryCommand({
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TableName: TABLE,
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KeyConditionExpression: 'PK = :pk',
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FilterExpression: 'visibility = :vis AND site = :site',
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ExpressionAttributeValues: { ':pk': `u#${did}#post`, ':vis': 'published', ':site': pubAtUri },
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ScanIndexForward: false,
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Limit: 100,
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})),
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resolveAuthorHandle(did),
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]);
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if (!pubResult.Item) {
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return { statusCode: 404, headers: { 'Content-Type': 'text/plain' }, body: 'Not found' };
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}
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const pub = pubResult.Item;
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const pubName = pub.name as string;
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const pubSiteUrl = (pub.url as string).replace(/\/$/, '');
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const pubDescription = pub.description as string | undefined;
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const posts = (postsResult.Items ?? []).slice(0, 20);
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const selfUrl = `https://${SITE_DOMAIN}${rawPath}`;
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const updatedAt = posts.length > 0
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? ((posts[0].updatedAt ?? posts[0].publishedAt) as string)
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: new Date().toISOString();
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const entryXml = posts.map((post) => {
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const base = (post.resolvedUrl as string | undefined ?? pubSiteUrl).replace(/\/$/, '');
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const postUrl = `${base}${post.path as string | undefined ?? ''}`;
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const summary = (post.description ?? post.textContent) as string | undefined;
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const lines = [
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' <entry>',
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` <id>${escXml(post.atUri as string)}</id>`,
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` <title>${escXml(post.title as string)}</title>`,
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` <link href="${escXml(postUrl)}" rel="alternate" type="text/html"/>`,
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` <published>${post.publishedAt as string}</published>`,
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` <updated>${(post.updatedAt ?? post.publishedAt) as string}</updated>`,
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];
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if (summary) lines.push(` <summary type="text">${escXml(summary)}</summary>`);
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lines.push(' </entry>');
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return lines.join('\n');
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});
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const feedLines = [
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'<?xml version="1.0" encoding="UTF-8"?>',
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'<feed xmlns="http://www.w3.org/2005/Atom">',
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` <id>${escXml(pubAtUri)}</id>`,
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` <title>${escXml(pubName)}</title>`,
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];
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if (pubDescription) feedLines.push(` <subtitle>${escXml(pubDescription)}</subtitle>`);
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feedLines.push(
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` <link href="${escXml(pubSiteUrl)}" rel="alternate" type="text/html"/>`,
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` <link href="${escXml(selfUrl)}" rel="self" type="application/atom+xml"/>`,
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` <updated>${updatedAt}</updated>`,
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' <author>',
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` <name>${escXml(authorHandle)}</name>`,
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' </author>',
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...entryXml,
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'</feed>',
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);
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return {
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statusCode: 200,
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headers: { 'Content-Type': 'application/atom+xml; charset=utf-8', 'Cache-Control': 'public, max-age=300' },
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body: feedLines.join('\n'),
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};
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}
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async function resolvePublicationMeta(atUri: string): Promise<{ url: string; name: string }> {
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const parts = atUri.slice('at://'.length).split('/')
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const pubDid = parts[0]
···
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// Public endpoints — no auth required.
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if (method === 'GET' && path.endsWith('/.well-known/site.standard.publication')) return verifyPublication(path);
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if (method === 'GET' && path.endsWith('/feed.xml')) return getPublicationFeed(path);
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if (method === 'GET' && path === '/feed') return getFeed(event);
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if (method === 'GET' && path === '/iframely') return getIframelyEmbed(event);
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if (method === 'GET' && path === '/posts/content') return getPublicPostContent(event);
+12
infra/cf/cloudfront.yaml
+12
infra/cf/cloudfront.yaml
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OriginSSLProtocols:
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- TLSv1.2
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CacheBehaviors:
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- PathPattern: '*/feed.xml'
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TargetOriginId: ApiGatewayOrigin
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ViewerProtocolPolicy: redirect-to-https
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AllowedMethods:
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- GET
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- HEAD
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CachedMethods:
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- GET
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- HEAD
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# CachingDisabled — every request reaches the Lambda
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CachePolicyId: 4135ea2d-6df8-44a3-9df3-4b5a84be39ad
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Compress: true
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- PathPattern: '*/.well-known/site.standard.publication'
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TargetOriginId: ApiGatewayOrigin
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ViewerProtocolPolicy: redirect-to-https