Redirects (#7067)

* Redirects spike

* Allow redirects in static mode

* Support in Netlify as well

* Adding a changeset

* Rename file

* Fix build problem

* Refactor to be more modular

* Fix location ref

* Late test should only run in SSR

* Support redirects in Netlify SSR configuration (#7167)

* Implement support for dynamic routes in redirects (#7173)

* Implement support for dynamic routes in redirects

* Remove the .only

* No need to special-case redirects in static build

* Implement support for redirects config in the Vercel adapter (#7182)

* Implement support for redirects config in the Vercel adapter

* Remove unused condition

* Move to a internal helper package

* Add support for the object notation in redirects

* Use status 308 for non-GET redirects (#7186)

* Implement redirects in Cloudflare (#7198)

* Implement redirects in Cloudflare

* Fix build

* Update tests b/c of new ordering

* Debug issue

* Use posix.join

* Update packages/underscore-redirects/package.json

Co-authored-by: Emanuele Stoppa <my.burning@gmail.com>

* Update based on review comments

* Update broken test

---------

Co-authored-by: Emanuele Stoppa <my.burning@gmail.com>

* Test that redirects can come from middleware (#7213)

* Test that redirects can come from middleware

* Allow non-promise returns for middleware

* Implement priority (#7210)

* Refactor

* Fix netlify test ordering

* Fix ordering again

* Redirects: Allow preventing the output of the static HTML file (#7245)

* Do a simple push for priority

* Adding changesets

* Put the implementation behind a flag.

* Self review

* Update .changeset/chatty-actors-stare.md

Co-authored-by: Chris Swithinbank <swithinbank@gmail.com>

* Update packages/astro/src/@types/astro.ts

Co-authored-by: Chris Swithinbank <swithinbank@gmail.com>

* Update packages/astro/src/@types/astro.ts

Co-authored-by: Chris Swithinbank <swithinbank@gmail.com>

* Update packages/astro/src/@types/astro.ts

Co-authored-by: Chris Swithinbank <swithinbank@gmail.com>

* Update packages/astro/src/@types/astro.ts

Co-authored-by: Chris Swithinbank <swithinbank@gmail.com>

* Update docs on dynamic restrictions.

* Update packages/astro/src/@types/astro.ts

Co-authored-by: Sarah Rainsberger <sarah@rainsberger.ca>

* Update packages/astro/src/@types/astro.ts

Co-authored-by: Sarah Rainsberger <sarah@rainsberger.ca>

* Code review changes

* Document netlify static adapter

* Update packages/astro/src/@types/astro.ts

Co-authored-by: Sarah Rainsberger <sarah@rainsberger.ca>

* Slight reword

* Update .changeset/twenty-suns-vanish.md

Co-authored-by: Sarah Rainsberger <sarah@rainsberger.ca>

* Add a note about public/_redirects file

* Update packages/astro/src/@types/astro.ts

Co-authored-by: Sarah Rainsberger <sarah@rainsberger.ca>

---------

Co-authored-by: Emanuele Stoppa <my.burning@gmail.com>
Co-authored-by: Chris Swithinbank <swithinbank@gmail.com>
Co-authored-by: Sarah Rainsberger <sarah@rainsberger.ca>
Co-authored-by: Nate Moore <natemoo-re@users.noreply.github.com>

3 files changed, 37 insertions, 130 deletions

diff --git a/packages/integrations/netlify/src/index.ts b/packages/integrations/netlify/src/index.ts
index fd7fd5fed..510e560f1 100644
--- a/packages/integrations/netlify/src/index.ts
+++ b/packages/integrations/netlify/src/index.ts
@@ -1,2 +1,3 @@
 export { netlifyEdgeFunctions } from './integration-edge-functions.js';
 export { netlifyFunctions as default, netlifyFunctions } from './integration-functions.js';
+export { netlifyStatic } from './integration-static.js';
diff --git a/packages/integrations/netlify/src/integration-static.ts b/packages/integrations/netlify/src/integration-static.ts
new file mode 100644
index 000000000..8814f9d2a
--- /dev/null
+++ b/packages/integrations/netlify/src/integration-static.ts
@@ -0,0 +1,26 @@
+import type { AstroAdapter, AstroConfig, AstroIntegration, RouteData } from 'astro';
+import type { Args } from './netlify-functions.js';
+import { createRedirects } from './shared.js';
+
+export function netlifyStatic(): AstroIntegration {
+	let _config: any;
+	return {
+		name: '@astrojs/netlify',
+		hooks: {
+			'astro:config:setup': ({ updateConfig }) => {
+				updateConfig({
+					build: {
+						// Do not output HTML redirects because we are building a `_redirects` file.
+						redirects: false,
+					},
+				});
+			},
+			'astro:config:done': ({ config }) => {
+				_config = config;
+			},
+			'astro:build:done': async ({ dir, routes }) => {
+				await createRedirects(_config, routes, dir, '', 'static');
+			}
+		}
+	};
+}
diff --git a/packages/integrations/netlify/src/shared.ts b/packages/integrations/netlify/src/shared.ts
index 78a61a800..d452ada10 100644
--- a/packages/integrations/netlify/src/shared.ts
+++ b/packages/integrations/netlify/src/shared.ts
@@ -1,145 +1,25 @@
 import type { AstroConfig, RouteData } from 'astro';
-import fs from 'fs';
-
-type RedirectDefinition = {
-	dynamic: boolean;
-	input: string;
-	target: string;
-	weight: 0 | 1;
-	status: 200 | 404;
-};
+import { createRedirectsFromAstroRoutes } from '@astrojs/underscore-redirects';
+import fs from 'node:fs';
 
 export async function createRedirects(
 	config: AstroConfig,
 	routes: RouteData[],
 	dir: URL,
 	entryFile: string,
-	type: 'functions' | 'edge-functions' | 'builders'
+	type: 'functions' | 'edge-functions' | 'builders' | 'static'
 ) {
-	const _redirectsURL = new URL('./_redirects', dir);
 	const kind = type ?? 'functions';
+	const dynamicTarget = `/.netlify/${kind}/${entryFile}`;
+	const _redirectsURL = new URL('./_redirects', dir);
 
-	const definitions: RedirectDefinition[] = [];
-
-	for (const route of routes) {
-		if (route.pathname) {
-			if (route.distURL) {
-				definitions.push({
-					dynamic: false,
-					input: route.pathname,
-					target: prependForwardSlash(route.distURL.toString().replace(dir.toString(), '')),
-					status: 200,
-					weight: 1,
-				});
-			} else {
-				definitions.push({
-					dynamic: false,
-					input: route.pathname,
-					target: `/.netlify/${kind}/${entryFile}`,
-					status: 200,
-					weight: 1,
-				});
-
-				if (route.route === '/404') {
-					definitions.push({
-						dynamic: true,
-						input: '/*',
-						target: `/.netlify/${kind}/${entryFile}`,
-						status: 404,
-						weight: 0,
-					});
-				}
-			}
-		} else {
-			const pattern =
-				'/' +
-				route.segments
-					.map(([part]) => {
-						//(part.dynamic ? '*' : part.content)
-						if (part.dynamic) {
-							if (part.spread) {
-								return '*';
-							} else {
-								return ':' + part.content;
-							}
-						} else {
-							return part.content;
-						}
-					})
-					.join('/');
-
-			if (route.distURL) {
-				const target =
-					`${pattern}` + (config.build.format === 'directory' ? '/index.html' : '.html');
-				definitions.push({
-					dynamic: true,
-					input: pattern,
-					target,
-					status: 200,
-					weight: 1,
-				});
-			} else {
-				definitions.push({
-					dynamic: true,
-					input: pattern,
-					target: `/.netlify/${kind}/${entryFile}`,
-					status: 200,
-					weight: 1,
-				});
-			}
-		}
-	}
-
-	let _redirects = prettify(definitions);
+	const _redirects = createRedirectsFromAstroRoutes({
+		config, routes, dir, dynamicTarget
+	});
+	const content = _redirects.print();
 
 	// Always use appendFile() because the redirects file could already exist,
 	// e.g. due to a `/public/_redirects` file that got copied to the output dir.
 	// If the file does not exist yet, appendFile() automatically creates it.
-	await fs.promises.appendFile(_redirectsURL, _redirects, 'utf-8');
-}
-
-function prettify(definitions: RedirectDefinition[]) {
-	let minInputLength = 0,
-		minTargetLength = 0;
-	definitions.sort((a, b) => {
-		// Find the longest input, so we can format things nicely
-		if (a.input.length > minInputLength) {
-			minInputLength = a.input.length;
-		}
-		if (b.input.length > minInputLength) {
-			minInputLength = b.input.length;
-		}
-
-		// Same for the target
-		if (a.target.length > minTargetLength) {
-			minTargetLength = a.target.length;
-		}
-		if (b.target.length > minTargetLength) {
-			minTargetLength = b.target.length;
-		}
-
-		// Sort dynamic routes on top
-		return b.weight - a.weight;
-	});
-
-	let _redirects = '';
-	// Loop over the definitions
-	definitions.forEach((defn, i) => {
-		// Figure out the number of spaces to add. We want at least 4 spaces
-		// after the input. This ensure that all targets line up together.
-		let inputSpaces = minInputLength - defn.input.length + 4;
-		let targetSpaces = minTargetLength - defn.target.length + 4;
-		_redirects +=
-			(i === 0 ? '' : '\n') +
-			defn.input +
-			' '.repeat(inputSpaces) +
-			defn.target +
-			' '.repeat(Math.abs(targetSpaces)) +
-			defn.status;
-	});
-	return _redirects;
-}
-
-function prependForwardSlash(str: string) {
-	return str[0] === '/' ? str : '/' + str;
+	await fs.promises.appendFile(_redirectsURL, content, 'utf-8');
 }