SyntaxCircus.Blazor.Seo 0.1.4

SyntaxCircus.Blazor.Seo

SEO building blocks for Blazor Server marketing sites — meta/OG/Twitter tags, typed Schema.org JSON-LD, and a canonical URL builder. Sitemap.xml, robots.txt, and canonical-host redirect are thin wrappers over SyntaxCircus.AspNetCore.Common, which this package depends on rather than reimplementing.

No support guaranteed. Published as-is and maintained on a best-effort basis. Issues and PRs are welcome, but there's no SLA — fork it or vendor what you need if that's not enough.

Breaking change from previous versions: SitemapEndpoint, RobotsTxtEndpoint, and CanonicalHostMiddleware are gone, replaced by SeoEndpointExtensions (MapSeoSitemap/MapSeoRobotsTxt) and AspNetCore.Common's canonical-host redirect. The canonical-host redirect is now an allow-list (CanonicalHost:LegacyHosts), not a deny-by-default redirect of every mismatched host. See CHANGELOG.md for details.

Setup

var builder = WebApplication.CreateBuilder(args);
builder.Services.AddSyntaxCircusSeo(builder.Configuration); // binds "Seo", "Support", "CanonicalHost", "SearchIndexing"

var app = builder.Build();
app.UseSyntaxCircusSeo(); // canonical-host redirect + X-Robots-Tag search-indexing headers

app.MapSeoSitemap(
    staticEntries:
    [
        new SitemapEntry(builder.Configuration["Seo:BaseUrl"] + "/", DateOnly.FromDateTime(DateTime.UtcNow), SitemapChangeFrequency.Weekly, 1.0),
        new SitemapEntry(builder.Configuration["Seo:BaseUrl"] + "/about", DateOnly.FromDateTime(DateTime.UtcNow)),
    ],
    dynamicEntriesProvider: async (services, ct) =>
    {
        var catalog = services.GetRequiredService<IMyCatalogService>();
        return catalog.GetEntries().Select(e => new SitemapEntry($"{baseUrl}/items/{e.Slug}", DateOnly.FromDateTime(e.UpdatedAt))).ToArray();
    });

app.MapSeoRobotsTxt();

SitemapEntry and SitemapChangeFrequency come from SyntaxCircus.AspNetCore.Common — see that package for the full sitemap/robots.txt/canonical-host/search-indexing option surface (CanonicalHost:CanonicalHost, CanonicalHost:LegacyHosts, SearchIndexing:BlockRobotsAndSitemap, etc.).

Configuration

Per-page meta tags

<SeoHead
    Title="Pricing"
    Description="Plans and pricing."
    RelativeUrl="/pricing"
    StructuredData="PageSchemas" />

@code {
    private IReadOnlyList<object> PageSchemas =>
    [
        new OrganizationSchema(
            Name: "Acme",
            Url: "https://acme.example",
            Logo: "https://acme.example/logo.png"),
        new BreadcrumbListSchema(
            [new BreadcrumbItem(1, "Home", "https://acme.example/"), new BreadcrumbItem(2, "Pricing", "https://acme.example/pricing")]),
    ];
}

SeoHead sets the document title and fills in description, canonical link, robots directives, and Open Graph/Twitter tags from SeoOptions plus whatever you override per-page. Its optional StructuredData parameter renders each supplied object as a JSON-LD block in the document head. JsonLd remains available when you prefer to place a single schema directly; both accept typed records from Schemas.cs (OrganizationSchema, WebSiteSchema, PersonSchema, CreativeWorkSchema, SoftwareApplicationSchema, BookSchema, BreadcrumbListSchema, FaqPageSchema) or your own POCO.

Notes

• MapSeoSitemap/MapSeoRobotsTxt return IEndpointRouteBuilder — the same builder you called them on, passed straight through from AspNetCore.Common's MapSitemap/MapRobotsTxt, not a per-route IEndpointConventionBuilder. Nothing can be chained onto the result (no .CacheOutput(...), .WithName(...), etc.) — that per-route builder isn't exposed by AspNetCore.Common's API. Pass the cacheDuration parameter instead to set a Cache-Control: public, max-age=... response header directly, e.g. app.MapSeoSitemap(entries, cacheDuration: TimeSpan.FromHours(1)).
• Neither endpoint is registered under a route name (no LinkGenerator/Url.RouteUrl(...) support) — the previous versions' .WithName("SyntaxCircusSitemap")/.WithName("SyntaxCircusRobotsTxt") calls had nowhere to attach once mapping moved into AspNetCore.Common. Reference /sitemap.xml//robots.txt by literal path if you need to link to them.
• ISeoUrlBuilder (injectable) resolves relative URLs against Seo:BaseUrl and can compute the canonical URL for the current request. MapSeoRobotsTxt uses it to auto-append the Sitemap: line.
• SearchIndexing:BlockRobotsAndSitemap (AspNetCore.Common) makes MapSeoRobotsTxt return a deny-all body and MapSeoSitemap return 404 — a single kill-switch for taking a site out of search indexing.

Contributing

Issues and pull requests are welcome:

• Keep changes focused, with a clear description of the behavior change.
• Match the existing code style (see .editorconfig).
• Call out any breaking changes to the public API in your PR description.

License

MIT — see LICENSE.txt.