feat(ext/http): auto-compression of fixed response bodies (#13769)

Co-authored-by: Ryan Dahl <ry@tinyclouds.org>
Co-authored-by: Satya Rohith <me@satyarohith.com>
Co-authored-by: Luca Casonato <lucacasonato@yahoo.com>

5 files changed, 1342 insertions, 4 deletions

diff --git a/Cargo.lock b/Cargo.lock
index caca6cde0..2208cd780 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -971,10 +971,15 @@ name = "deno_http"
 version = "0.31.0"
 dependencies = [
  "base64 0.13.0",
+ "brotli",
  "bytes",
+ "cache_control",
  "deno_core",
  "deno_websocket",
+ "flate2",
+ "fly-accept-encoding",
  "hyper",
+ "mime",
  "percent-encoding",
  "ring",
  "serde",
@@ -1506,6 +1511,16 @@ dependencies = [
 ]
 
 [[package]]
+name = "fly-accept-encoding"
+version = "0.2.0-alpha.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "741d3e4ac3bcebc022cd90e7d1ce376515a73db2d53ba7fd3a7e581d6db7fa97"
+dependencies = [
+ "http",
+ "thiserror",
+]
+
+[[package]]
 name = "fnv"
 version = "1.0.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
diff --git a/cli/tests/unit/http_test.ts b/cli/tests/unit/http_test.ts
index 5ff1475b3..68500006f 100644
--- a/cli/tests/unit/http_test.ts
+++ b/cli/tests/unit/http_test.ts
@@ -95,7 +95,7 @@ Deno.test(
 
     const resp = new Uint8Array(200);
     const readResult = await conn.read(resp);
-    assertEquals(readResult, 115);
+    assertEquals(readResult, 138);
 
     conn.close();
 
@@ -1165,7 +1165,7 @@ Deno.test(
 
     const resp = new Uint8Array(200);
     const readResult = await conn.read(resp);
-    assertEquals(readResult, 115);
+    assertEquals(readResult, 138);
 
     conn.close();
 
@@ -1173,6 +1173,505 @@ Deno.test(
   },
 );
 
+/* Automatic Body Compression */
+
+const decoder = new TextDecoder();
+
+Deno.test({
+  name: "http server compresses body",
+  permissions: { net: true },
+  async fn() {
+    const hostname = "localhost";
+    const port = 4501;
+
+    async function server() {
+      const listener = Deno.listen({ hostname, port });
+      const tcpConn = await listener.accept();
+      const httpConn = Deno.serveHttp(tcpConn);
+      const e = await httpConn.nextRequest();
+      assert(e);
+      const { request, respondWith } = e;
+      assertEquals(request.headers.get("Accept-Encoding"), "gzip, deflate, br");
+      const response = new Response(
+        JSON.stringify({ hello: "deno", now: "with", compressed: "body" }),
+        {
+          headers: { "content-type": "application/json" },
+        },
+      );
+      await respondWith(response);
+      httpConn.close();
+      listener.close();
+    }
+
+    async function client() {
+      const url = `http://${hostname}:${port}/`;
+      const cmd = [
+        "curl",
+        "-I",
+        "--request",
+        "GET",
+        "--url",
+        url,
+        "--header",
+        "Accept-Encoding: gzip, deflate, br",
+      ];
+      const proc = Deno.run({ cmd, stdout: "piped", stderr: "null" });
+      const status = await proc.status();
+      assert(status.success);
+      const output = decoder.decode(await proc.output());
+      assert(output.includes("vary: Accept-Encoding\r\n"));
+      assert(output.includes("content-encoding: gzip\r\n"));
+      proc.close();
+    }
+
+    await Promise.all([server(), client()]);
+  },
+});
+
+Deno.test({
+  name: "http server doesn't compress small body",
+  permissions: { net: true },
+  async fn() {
+    const hostname = "localhost";
+    const port = 4501;
+
+    async function server() {
+      const listener = Deno.listen({ hostname, port });
+      const tcpConn = await listener.accept();
+      const httpConn = Deno.serveHttp(tcpConn);
+      const e = await httpConn.nextRequest();
+      assert(e);
+      const { request, respondWith } = e;
+      assertEquals(request.headers.get("Accept-Encoding"), "gzip, deflate, br");
+      const response = new Response(
+        JSON.stringify({ hello: "deno" }),
+        {
+          headers: { "content-type": "application/json" },
+        },
+      );
+      await respondWith(response);
+      httpConn.close();
+      listener.close();
+    }
+
+    async function client() {
+      const url = `http://${hostname}:${port}/`;
+      const cmd = [
+        "curl",
+        "-I",
+        "--request",
+        "GET",
+        "--url",
+        url,
+        "--header",
+        "Accept-Encoding: gzip, deflate, br",
+      ];
+      const proc = Deno.run({ cmd, stdout: "piped", stderr: "null" });
+      const status = await proc.status();
+      assert(status.success);
+      const output = decoder.decode(await proc.output()).toLocaleLowerCase();
+      assert(output.includes("vary: accept-encoding\r\n"));
+      assert(!output.includes("content-encoding: "));
+      proc.close();
+    }
+
+    await Promise.all([server(), client()]);
+  },
+});
+
+Deno.test({
+  name: "http server respects accept-encoding weights",
+  permissions: { net: true },
+  async fn() {
+    const hostname = "localhost";
+    const port = 4501;
+
+    async function server() {
+      const listener = Deno.listen({ hostname, port });
+      const tcpConn = await listener.accept();
+      const httpConn = Deno.serveHttp(tcpConn);
+      const e = await httpConn.nextRequest();
+      assert(e);
+      const { request, respondWith } = e;
+      assertEquals(
+        request.headers.get("Accept-Encoding"),
+        "gzip;q=0.8, br;q=1.0, *;q=0.1",
+      );
+      const response = new Response(
+        JSON.stringify({ hello: "deno", now: "with", compressed: "body" }),
+        {
+          headers: { "content-type": "application/json" },
+        },
+      );
+      await respondWith(response);
+      httpConn.close();
+      listener.close();
+    }
+
+    async function client() {
+      const url = `http://${hostname}:${port}/`;
+      const cmd = [
+        "curl",
+        "-I",
+        "--request",
+        "GET",
+        "--url",
+        url,
+        "--header",
+        "Accept-Encoding: gzip;q=0.8, br;q=1.0, *;q=0.1",
+      ];
+      const proc = Deno.run({ cmd, stdout: "piped", stderr: "null" });
+      const status = await proc.status();
+      assert(status.success);
+      const output = decoder.decode(await proc.output());
+      assert(output.includes("vary: Accept-Encoding\r\n"));
+      assert(output.includes("content-encoding: br\r\n"));
+      proc.close();
+    }
+
+    await Promise.all([server(), client()]);
+  },
+});
+
+Deno.test({
+  name: "http server augments vary header",
+  permissions: { net: true },
+  async fn() {
+    const hostname = "localhost";
+    const port = 4501;
+
+    async function server() {
+      const listener = Deno.listen({ hostname, port });
+      const tcpConn = await listener.accept();
+      const httpConn = Deno.serveHttp(tcpConn);
+      const e = await httpConn.nextRequest();
+      assert(e);
+      const { request, respondWith } = e;
+      assertEquals(request.headers.get("Accept-Encoding"), "gzip, deflate, br");
+      const response = new Response(
+        JSON.stringify({ hello: "deno", now: "with", compressed: "body" }),
+        {
+          headers: { "content-type": "application/json", vary: "Accept" },
+        },
+      );
+      await respondWith(response);
+      httpConn.close();
+      listener.close();
+    }
+
+    async function client() {
+      const url = `http://${hostname}:${port}/`;
+      const cmd = [
+        "curl",
+        "-I",
+        "--request",
+        "GET",
+        "--url",
+        url,
+        "--header",
+        "Accept-Encoding: gzip, deflate, br",
+      ];
+      const proc = Deno.run({ cmd, stdout: "piped", stderr: "null" });
+      const status = await proc.status();
+      assert(status.success);
+      const output = decoder.decode(await proc.output());
+      assert(output.includes("vary: Accept-Encoding, Accept\r\n"));
+      assert(output.includes("content-encoding: gzip\r\n"));
+      proc.close();
+    }
+
+    await Promise.all([server(), client()]);
+  },
+});
+
+Deno.test({
+  name: "http server weakens etag header",
+  permissions: { net: true },
+  async fn() {
+    const hostname = "localhost";
+    const port = 4501;
+
+    async function server() {
+      const listener = Deno.listen({ hostname, port });
+      const tcpConn = await listener.accept();
+      const httpConn = Deno.serveHttp(tcpConn);
+      const e = await httpConn.nextRequest();
+      assert(e);
+      const { request, respondWith } = e;
+      assertEquals(request.headers.get("Accept-Encoding"), "gzip, deflate, br");
+      const response = new Response(
+        JSON.stringify({ hello: "deno", now: "with", compressed: "body" }),
+        {
+          headers: {
+            "content-type": "application/json",
+            etag: "33a64df551425fcc55e4d42a148795d9f25f89d4",
+          },
+        },
+      );
+      await respondWith(response);
+      httpConn.close();
+      listener.close();
+    }
+
+    async function client() {
+      const url = `http://${hostname}:${port}/`;
+      const cmd = [
+        "curl",
+        "-I",
+        "--request",
+        "GET",
+        "--url",
+        url,
+        "--header",
+        "Accept-Encoding: gzip, deflate, br",
+      ];
+      const proc = Deno.run({ cmd, stdout: "piped", stderr: "null" });
+      const status = await proc.status();
+      assert(status.success);
+      const output = decoder.decode(await proc.output());
+      assert(output.includes("vary: Accept-Encoding\r\n"));
+      assert(
+        output.includes("etag: W/33a64df551425fcc55e4d42a148795d9f25f89d4\r\n"),
+      );
+      assert(output.includes("content-encoding: gzip\r\n"));
+      proc.close();
+    }
+
+    await Promise.all([server(), client()]);
+  },
+});
+
+Deno.test({
+  name: "http server passes through weak etag header",
+  permissions: { net: true },
+  async fn() {
+    const hostname = "localhost";
+    const port = 4501;
+
+    async function server() {
+      const listener = Deno.listen({ hostname, port });
+      const tcpConn = await listener.accept();
+      const httpConn = Deno.serveHttp(tcpConn);
+      const e = await httpConn.nextRequest();
+      assert(e);
+      const { request, respondWith } = e;
+      assertEquals(request.headers.get("Accept-Encoding"), "gzip, deflate, br");
+      const response = new Response(
+        JSON.stringify({ hello: "deno", now: "with", compressed: "body" }),
+        {
+          headers: {
+            "content-type": "application/json",
+            etag: "W/33a64df551425fcc55e4d42a148795d9f25f89d4",
+          },
+        },
+      );
+      await respondWith(response);
+      httpConn.close();
+      listener.close();
+    }
+
+    async function client() {
+      const url = `http://${hostname}:${port}/`;
+      const cmd = [
+        "curl",
+        "-I",
+        "--request",
+        "GET",
+        "--url",
+        url,
+        "--header",
+        "Accept-Encoding: gzip, deflate, br",
+      ];
+      const proc = Deno.run({ cmd, stdout: "piped", stderr: "null" });
+      const status = await proc.status();
+      assert(status.success);
+      const output = decoder.decode(await proc.output());
+      assert(output.includes("vary: Accept-Encoding\r\n"));
+      assert(
+        output.includes("etag: W/33a64df551425fcc55e4d42a148795d9f25f89d4\r\n"),
+      );
+      assert(output.includes("content-encoding: gzip\r\n"));
+      proc.close();
+    }
+
+    await Promise.all([server(), client()]);
+  },
+});
+
+Deno.test({
+  name: "http server doesn't compress body when no-transform is set",
+  permissions: { net: true },
+  async fn() {
+    const hostname = "localhost";
+    const port = 4501;
+
+    async function server() {
+      const listener = Deno.listen({ hostname, port });
+      const tcpConn = await listener.accept();
+      const httpConn = Deno.serveHttp(tcpConn);
+      const e = await httpConn.nextRequest();
+      assert(e);
+      const { request, respondWith } = e;
+      assertEquals(request.headers.get("Accept-Encoding"), "gzip, deflate, br");
+      const response = new Response(
+        JSON.stringify({ hello: "deno", now: "with", compressed: "body" }),
+        {
+          headers: {
+            "content-type": "application/json",
+            "cache-control": "no-transform",
+          },
+        },
+      );
+      await respondWith(response);
+      httpConn.close();
+      listener.close();
+    }
+
+    async function client() {
+      const url = `http://${hostname}:${port}/`;
+      const cmd = [
+        "curl",
+        "-I",
+        "--request",
+        "GET",
+        "--url",
+        url,
+        "--header",
+        "Accept-Encoding: gzip, deflate, br",
+      ];
+      const proc = Deno.run({ cmd, stdout: "piped", stderr: "null" });
+      const status = await proc.status();
+      assert(status.success);
+      const output = decoder.decode(await proc.output());
+      assert(output.includes("vary: Accept-Encoding\r\n"));
+      assert(!output.includes("content-encoding: "));
+      proc.close();
+    }
+
+    await Promise.all([server(), client()]);
+  },
+});
+
+Deno.test({
+  name: "http server doesn't compress body when content-range is set",
+  permissions: { net: true },
+  async fn() {
+    const hostname = "localhost";
+    const port = 4501;
+
+    async function server() {
+      const listener = Deno.listen({ hostname, port });
+      const tcpConn = await listener.accept();
+      const httpConn = Deno.serveHttp(tcpConn);
+      const e = await httpConn.nextRequest();
+      assert(e);
+      const { request, respondWith } = e;
+      assertEquals(request.headers.get("Accept-Encoding"), "gzip, deflate, br");
+      const response = new Response(
+        JSON.stringify({ hello: "deno", now: "with", compressed: "body" }),
+        {
+          headers: {
+            "content-type": "application/json",
+            "content-range": "bytes 200-100/67589",
+          },
+        },
+      );
+      await respondWith(response);
+      httpConn.close();
+      listener.close();
+    }
+
+    async function client() {
+      const url = `http://${hostname}:${port}/`;
+      const cmd = [
+        "curl",
+        "-I",
+        "--request",
+        "GET",
+        "--url",
+        url,
+        "--header",
+        "Accept-Encoding: gzip, deflate, br",
+      ];
+      const proc = Deno.run({ cmd, stdout: "piped", stderr: "null" });
+      const status = await proc.status();
+      assert(status.success);
+      const output = decoder.decode(await proc.output());
+      assert(output.includes("vary: Accept-Encoding\r\n"));
+      assert(!output.includes("content-encoding: "));
+      proc.close();
+    }
+
+    await Promise.all([server(), client()]);
+  },
+});
+
+Deno.test({
+  name: "http server doesn't compress streamed bodies",
+  permissions: { net: true },
+  async fn() {
+    const hostname = "localhost";
+    const port = 4501;
+
+    async function server() {
+      const encoder = new TextEncoder();
+      const listener = Deno.listen({ hostname, port });
+      const tcpConn = await listener.accept();
+      const httpConn = Deno.serveHttp(tcpConn);
+      const e = await httpConn.nextRequest();
+      assert(e);
+      const { request, respondWith } = e;
+      assertEquals(request.headers.get("Accept-Encoding"), "gzip, deflate, br");
+      const bodyInit = new ReadableStream({
+        start(controller) {
+          controller.enqueue(
+            encoder.encode(
+              JSON.stringify({
+                hello: "deno",
+                now: "with",
+                compressed: "body",
+              }),
+            ),
+          );
+          controller.close();
+        },
+      });
+      const response = new Response(
+        bodyInit,
+        {
+          headers: { "content-type": "application/json", vary: "Accept" },
+        },
+      );
+      await respondWith(response);
+      httpConn.close();
+      listener.close();
+    }
+
+    async function client() {
+      const url = `http://${hostname}:${port}/`;
+      const cmd = [
+        "curl",
+        "-I",
+        "--request",
+        "GET",
+        "--url",
+        url,
+        "--header",
+        "Accept-Encoding: gzip, deflate, br",
+      ];
+      const proc = Deno.run({ cmd, stdout: "piped", stderr: "null" });
+      const status = await proc.status();
+      assert(status.success);
+      const output = decoder.decode(await proc.output());
+      assert(output.includes("vary: Accept\r\n"));
+      assert(!output.includes("content-encoding: "));
+      proc.close();
+    }
+
+    await Promise.all([server(), client()]);
+  },
+});
+
 function chunkedBodyReader(h: Headers, r: BufReader): Deno.Reader {
   // Based on https://tools.ietf.org/html/rfc2616#section-19.4.6
   const tp = new TextProtoReader(r);
diff --git a/ext/http/Cargo.toml b/ext/http/Cargo.toml
index dce6a59eb..58cf21038 100644
--- a/ext/http/Cargo.toml
+++ b/ext/http/Cargo.toml
@@ -15,10 +15,15 @@ path = "lib.rs"
 
 [dependencies]
 base64 = "0.13.0"
+brotli = "3.3.3"
 bytes = "1"
+cache_control = "0.2.0"
 deno_core = { version = "0.121.0", path = "../../core" }
 deno_websocket = { version = "0.44.0", path = "../websocket" }
+flate2 = "1.0.22"
+fly-accept-encoding = "0.2.0-alpha.5"
 hyper = { version = "0.14.9", features = ["server", "stream", "http1", "http2", "runtime"] }
+mime = "0.3.16"
 percent-encoding = "2.1.0"
 ring = "0.16.20"
 serde = { version = "1.0.129", features = ["derive"] }
diff --git a/ext/http/compressible.rs b/ext/http/compressible.rs
new file mode 100644
index 000000000..21cd42c76
--- /dev/null
+++ b/ext/http/compressible.rs
@@ -0,0 +1,660 @@
+// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
+
+use deno_core::ByteString;
+
+// Data obtained from https://github.com/jshttp/mime-db/blob/fa5e4ef3cc8907ec3c5ec5b85af0c63d7059a5cd/db.json
+// Important! Keep this list sorted alphabetically.
+const CONTENT_TYPES: &[&str] = &[
+  "application/3gpdash-qoe-report+xml",
+  "application/3gpp-ims+xml",
+  "application/3gpphal+json",
+  "application/3gpphalforms+json",
+  "application/activity+json",
+  "application/alto-costmap+json",
+  "application/alto-costmapfilter+json",
+  "application/alto-directory+json",
+  "application/alto-endpointcost+json",
+  "application/alto-endpointcostparams+json",
+  "application/alto-endpointprop+json",
+  "application/alto-endpointpropparams+json",
+  "application/alto-error+json",
+  "application/alto-networkmap+json",
+  "application/alto-networkmapfilter+json",
+  "application/alto-updatestreamcontrol+json",
+  "application/alto-updatestreamparams+json",
+  "application/atom+xml",
+  "application/atomcat+xml",
+  "application/atomdeleted+xml",
+  "application/atomsvc+xml",
+  "application/atsc-dwd+xml",
+  "application/atsc-held+xml",
+  "application/atsc-rdt+json",
+  "application/atsc-rsat+xml",
+  "application/auth-policy+xml",
+  "application/beep+xml",
+  "application/calendar+json",
+  "application/calendar+xml",
+  "application/captive+json",
+  "application/ccmp+xml",
+  "application/ccxml+xml",
+  "application/cdfx+xml",
+  "application/cea-2018+xml",
+  "application/cellml+xml",
+  "application/clue+xml",
+  "application/clue_info+xml",
+  "application/cnrp+xml",
+  "application/coap-group+json",
+  "application/conference-info+xml",
+  "application/cpl+xml",
+  "application/csta+xml",
+  "application/cstadata+xml",
+  "application/csvm+json",
+  "application/dart",
+  "application/dash+xml",
+  "application/davmount+xml",
+  "application/dialog-info+xml",
+  "application/dicom+json",
+  "application/dicom+xml",
+  "application/dns+json",
+  "application/docbook+xml",
+  "application/dskpp+xml",
+  "application/dssc+xml",
+  "application/ecmascript",
+  "application/elm+json",
+  "application/elm+xml",
+  "application/emergencycalldata.cap+xml",
+  "application/emergencycalldata.comment+xml",
+  "application/emergencycalldata.control+xml",
+  "application/emergencycalldata.deviceinfo+xml",
+  "application/emergencycalldata.providerinfo+xml",
+  "application/emergencycalldata.serviceinfo+xml",
+  "application/emergencycalldata.subscriberinfo+xml",
+  "application/emergencycalldata.veds+xml",
+  "application/emma+xml",
+  "application/emotionml+xml",
+  "application/epp+xml",
+  "application/expect-ct-report+json",
+  "application/fdt+xml",
+  "application/fhir+json",
+  "application/fhir+xml",
+  "application/fido.trusted-apps+json",
+  "application/framework-attributes+xml",
+  "application/geo+json",
+  "application/geoxacml+xml",
+  "application/gml+xml",
+  "application/gpx+xml",
+  "application/held+xml",
+  "application/ibe-key-request+xml",
+  "application/ibe-pkg-reply+xml",
+  "application/im-iscomposing+xml",
+  "application/inkml+xml",
+  "application/its+xml",
+  "application/javascript",
+  "application/jf2feed+json",
+  "application/jose+json",
+  "application/jrd+json",
+  "application/jscalendar+json",
+  "application/json",
+  "application/json-patch+json",
+  "application/jsonml+json",
+  "application/jwk+json",
+  "application/jwk-set+json",
+  "application/kpml-request+xml",
+  "application/kpml-response+xml",
+  "application/ld+json",
+  "application/lgr+xml",
+  "application/load-control+xml",
+  "application/lost+xml",
+  "application/lostsync+xml",
+  "application/mads+xml",
+  "application/manifest+json",
+  "application/marcxml+xml",
+  "application/mathml+xml",
+  "application/mathml-content+xml",
+  "application/mathml-presentation+xml",
+  "application/mbms-associated-procedure-description+xml",
+  "application/mbms-deregister+xml",
+  "application/mbms-envelope+xml",
+  "application/mbms-msk+xml",
+  "application/mbms-msk-response+xml",
+  "application/mbms-protection-description+xml",
+  "application/mbms-reception-report+xml",
+  "application/mbms-register+xml",
+  "application/mbms-register-response+xml",
+  "application/mbms-schedule+xml",
+  "application/mbms-user-service-description+xml",
+  "application/media-policy-dataset+xml",
+  "application/media_control+xml",
+  "application/mediaservercontrol+xml",
+  "application/merge-patch+json",
+  "application/metalink+xml",
+  "application/metalink4+xml",
+  "application/mets+xml",
+  "application/mmt-aei+xml",
+  "application/mmt-usd+xml",
+  "application/mods+xml",
+  "application/mrb-consumer+xml",
+  "application/mrb-publish+xml",
+  "application/msc-ivr+xml",
+  "application/msc-mixer+xml",
+  "application/mud+json",
+  "application/nlsml+xml",
+  "application/odm+xml",
+  "application/oebps-package+xml",
+  "application/omdoc+xml",
+  "application/opc-nodeset+xml",
+  "application/p2p-overlay+xml",
+  "application/patch-ops-error+xml",
+  "application/pidf+xml",
+  "application/pidf-diff+xml",
+  "application/pls+xml",
+  "application/poc-settings+xml",
+  "application/postscript",
+  "application/ppsp-tracker+json",
+  "application/problem+json",
+  "application/problem+xml",
+  "application/provenance+xml",
+  "application/prs.xsf+xml",
+  "application/pskc+xml",
+  "application/pvd+json",
+  "application/raml+yaml",
+  "application/rdap+json",
+  "application/rdf+xml",
+  "application/reginfo+xml",
+  "application/reputon+json",
+  "application/resource-lists+xml",
+  "application/resource-lists-diff+xml",
+  "application/rfc+xml",
+  "application/rlmi+xml",
+  "application/rls-services+xml",
+  "application/route-apd+xml",
+  "application/route-s-tsid+xml",
+  "application/route-usd+xml",
+  "application/rsd+xml",
+  "application/rss+xml",
+  "application/rtf",
+  "application/samlassertion+xml",
+  "application/samlmetadata+xml",
+  "application/sarif+json",
+  "application/sarif-external-properties+json",
+  "application/sbml+xml",
+  "application/scaip+xml",
+  "application/scim+json",
+  "application/senml+json",
+  "application/senml+xml",
+  "application/senml-etch+json",
+  "application/sensml+json",
+  "application/sensml+xml",
+  "application/sep+xml",
+  "application/shf+xml",
+  "application/simple-filter+xml",
+  "application/smil+xml",
+  "application/soap+xml",
+  "application/sparql-results+xml",
+  "application/spirits-event+xml",
+  "application/srgs+xml",
+  "application/sru+xml",
+  "application/ssdl+xml",
+  "application/ssml+xml",
+  "application/stix+json",
+  "application/swid+xml",
+  "application/tar",
+  "application/taxii+json",
+  "application/td+json",
+  "application/tei+xml",
+  "application/thraud+xml",
+  "application/tlsrpt+json",
+  "application/toml",
+  "application/ttml+xml",
+  "application/urc-grpsheet+xml",
+  "application/urc-ressheet+xml",
+  "application/urc-targetdesc+xml",
+  "application/urc-uisocketdesc+xml",
+  "application/vcard+json",
+  "application/vcard+xml",
+  "application/vnd.1000minds.decision-model+xml",
+  "application/vnd.3gpp-prose+xml",
+  "application/vnd.3gpp-prose-pc3ch+xml",
+  "application/vnd.3gpp.access-transfer-events+xml",
+  "application/vnd.3gpp.bsf+xml",
+  "application/vnd.3gpp.gmop+xml",
+  "application/vnd.3gpp.mcdata-affiliation-command+xml",
+  "application/vnd.3gpp.mcdata-info+xml",
+  "application/vnd.3gpp.mcdata-service-config+xml",
+  "application/vnd.3gpp.mcdata-ue-config+xml",
+  "application/vnd.3gpp.mcdata-user-profile+xml",
+  "application/vnd.3gpp.mcptt-affiliation-command+xml",
+  "application/vnd.3gpp.mcptt-floor-request+xml",
+  "application/vnd.3gpp.mcptt-info+xml",
+  "application/vnd.3gpp.mcptt-location-info+xml",
+  "application/vnd.3gpp.mcptt-mbms-usage-info+xml",
+  "application/vnd.3gpp.mcptt-service-config+xml",
+  "application/vnd.3gpp.mcptt-signed+xml",
+  "application/vnd.3gpp.mcptt-ue-config+xml",
+  "application/vnd.3gpp.mcptt-ue-init-config+xml",
+  "application/vnd.3gpp.mcptt-user-profile+xml",
+  "application/vnd.3gpp.mcvideo-affiliation-command+xml",
+  "application/vnd.3gpp.mcvideo-affiliation-info+xml",
+  "application/vnd.3gpp.mcvideo-info+xml",
+  "application/vnd.3gpp.mcvideo-location-info+xml",
+  "application/vnd.3gpp.mcvideo-mbms-usage-info+xml",
+  "application/vnd.3gpp.mcvideo-service-config+xml",
+  "application/vnd.3gpp.mcvideo-transmission-request+xml",
+  "application/vnd.3gpp.mcvideo-ue-config+xml",
+  "application/vnd.3gpp.mcvideo-user-profile+xml",
+  "application/vnd.3gpp.mid-call+xml",
+  "application/vnd.3gpp.sms+xml",
+  "application/vnd.3gpp.srvcc-ext+xml",
+  "application/vnd.3gpp.srvcc-info+xml",
+  "application/vnd.3gpp.state-and-event-info+xml",
+  "application/vnd.3gpp.ussd+xml",
+  "application/vnd.3gpp2.bcmcsinfo+xml",
+  "application/vnd.adobe.xdp+xml",
+  "application/vnd.amadeus+json",
+  "application/vnd.amundsen.maze+xml",
+  "application/vnd.api+json",
+  "application/vnd.aplextor.warrp+json",
+  "application/vnd.apothekende.reservation+json",
+  "application/vnd.apple.installer+xml",
+  "application/vnd.artisan+json",
+  "application/vnd.avalon+json",
+  "application/vnd.avistar+xml",
+  "application/vnd.balsamiq.bmml+xml",
+  "application/vnd.bbf.usp.msg+json",
+  "application/vnd.bekitzur-stech+json",
+  "application/vnd.biopax.rdf+xml",
+  "application/vnd.byu.uapi+json",
+  "application/vnd.capasystems-pg+json",
+  "application/vnd.chemdraw+xml",
+  "application/vnd.citationstyles.style+xml",
+  "application/vnd.collection+json",
+  "application/vnd.collection.doc+json",
+  "application/vnd.collection.next+json",
+  "application/vnd.coreos.ignition+json",
+  "application/vnd.criticaltools.wbs+xml",
+  "application/vnd.cryptii.pipe+json",
+  "application/vnd.ctct.ws+xml",
+  "application/vnd.cyan.dean.root+xml",
+  "application/vnd.cyclonedx+json",
+  "application/vnd.cyclonedx+xml",
+  "application/vnd.dart",
+  "application/vnd.datapackage+json",
+  "application/vnd.dataresource+json",
+  "application/vnd.dece.ttml+xml",
+  "application/vnd.dm.delegation+xml",
+  "application/vnd.document+json",
+  "application/vnd.drive+json",
+  "application/vnd.dvb.dvbisl+xml",
+  "application/vnd.dvb.notif-aggregate-root+xml",
+  "application/vnd.dvb.notif-container+xml",
+  "application/vnd.dvb.notif-generic+xml",
+  "application/vnd.dvb.notif-ia-msglist+xml",
+  "application/vnd.dvb.notif-ia-registration-request+xml",
+  "application/vnd.dvb.notif-ia-registration-response+xml",
+  "application/vnd.dvb.notif-init+xml",
+  "application/vnd.emclient.accessrequest+xml",
+  "application/vnd.eprints.data+xml",
+  "application/vnd.eszigno3+xml",
+  "application/vnd.etsi.aoc+xml",
+  "application/vnd.etsi.cug+xml",
+  "application/vnd.etsi.iptvcommand+xml",
+  "application/vnd.etsi.iptvdiscovery+xml",
+  "application/vnd.etsi.iptvprofile+xml",
+  "application/vnd.etsi.iptvsad-bc+xml",
+  "application/vnd.etsi.iptvsad-cod+xml",
+  "application/vnd.etsi.iptvsad-npvr+xml",
+  "application/vnd.etsi.iptvservice+xml",
+  "application/vnd.etsi.iptvsync+xml",
+  "application/vnd.etsi.iptvueprofile+xml",
+  "application/vnd.etsi.mcid+xml",
+  "application/vnd.etsi.overload-control-policy-dataset+xml",
+  "application/vnd.etsi.pstn+xml",
+  "application/vnd.etsi.sci+xml",
+  "application/vnd.etsi.simservs+xml",
+  "application/vnd.etsi.tsl+xml",
+  "application/vnd.fujifilm.fb.jfi+xml",
+  "application/vnd.futoin+json",
+  "application/vnd.gentics.grd+json",
+  "application/vnd.geo+json",
+  "application/vnd.geocube+xml",
+  "application/vnd.google-earth.kml+xml",
+  "application/vnd.gov.sk.e-form+xml",
+  "application/vnd.gov.sk.xmldatacontainer+xml",
+  "application/vnd.hal+json",
+  "application/vnd.hal+xml",
+  "application/vnd.handheld-entertainment+xml",
+  "application/vnd.hc+json",
+  "application/vnd.heroku+json",
+  "application/vnd.hyper+json",
+  "application/vnd.hyper-item+json",
+  "application/vnd.hyperdrive+json",
+  "application/vnd.ims.lis.v2.result+json",
+  "application/vnd.ims.lti.v2.toolconsumerprofile+json",
+  "application/vnd.ims.lti.v2.toolproxy+json",
+  "application/vnd.ims.lti.v2.toolproxy.id+json",
+  "application/vnd.ims.lti.v2.toolsettings+json",
+  "application/vnd.ims.lti.v2.toolsettings.simple+json",
+  "application/vnd.informedcontrol.rms+xml",
+  "application/vnd.infotech.project+xml",
+  "application/vnd.iptc.g2.catalogitem+xml",
+  "application/vnd.iptc.g2.conceptitem+xml",
+  "application/vnd.iptc.g2.knowledgeitem+xml",
+  "application/vnd.iptc.g2.newsitem+xml",
+  "application/vnd.iptc.g2.newsmessage+xml",
+  "application/vnd.iptc.g2.packageitem+xml",
+  "application/vnd.iptc.g2.planningitem+xml",
+  "application/vnd.irepository.package+xml",
+  "application/vnd.las.las+json",
+  "application/vnd.las.las+xml",
+  "application/vnd.leap+json",
+  "application/vnd.liberty-request+xml",
+  "application/vnd.llamagraphics.life-balance.exchange+xml",
+  "application/vnd.marlin.drm.actiontoken+xml",
+  "application/vnd.marlin.drm.conftoken+xml",
+  "application/vnd.marlin.drm.license+xml",
+  "application/vnd.mason+json",
+  "application/vnd.micro+json",
+  "application/vnd.miele+json",
+  "application/vnd.mozilla.xul+xml",
+  "application/vnd.ms-fontobject",
+  "application/vnd.ms-office.activex+xml",
+  "application/vnd.ms-opentype",
+  "application/vnd.ms-playready.initiator+xml",
+  "application/vnd.ms-printdevicecapabilities+xml",
+  "application/vnd.ms-printing.printticket+xml",
+  "application/vnd.ms-printschematicket+xml",
+  "application/vnd.nearst.inv+json",
+  "application/vnd.nokia.conml+xml",
+  "application/vnd.nokia.iptv.config+xml",
+  "application/vnd.nokia.landmark+xml",
+  "application/vnd.nokia.landmarkcollection+xml",
+  "application/vnd.nokia.n-gage.ac+xml",
+  "application/vnd.nokia.pcd+xml",
+  "application/vnd.oci.image.manifest.v1+json",
+  "application/vnd.oftn.l10n+json",
+  "application/vnd.oipf.contentaccessdownload+xml",
+  "application/vnd.oipf.contentaccessstreaming+xml",
+  "application/vnd.oipf.dae.svg+xml",
+  "application/vnd.oipf.dae.xhtml+xml",
+  "application/vnd.oipf.mippvcontrolmessage+xml",
+  "application/vnd.oipf.spdiscovery+xml",
+  "application/vnd.oipf.spdlist+xml",
+  "application/vnd.oipf.ueprofile+xml",
+  "application/vnd.oipf.userprofile+xml",
+  "application/vnd.oma.bcast.associated-procedure-parameter+xml",
+  "application/vnd.oma.bcast.drm-trigger+xml",
+  "application/vnd.oma.bcast.imd+xml",
+  "application/vnd.oma.bcast.notification+xml",
+  "application/vnd.oma.bcast.sgdd+xml",
+  "application/vnd.oma.bcast.smartcard-trigger+xml",
+  "application/vnd.oma.bcast.sprov+xml",
+  "application/vnd.oma.cab-address-book+xml",
+  "application/vnd.oma.cab-feature-handler+xml",
+  "application/vnd.oma.cab-pcc+xml",
+  "application/vnd.oma.cab-subs-invite+xml",
+  "application/vnd.oma.cab-user-prefs+xml",
+  "application/vnd.oma.dd2+xml",
+  "application/vnd.oma.drm.risd+xml",
+  "application/vnd.oma.group-usage-list+xml",
+  "application/vnd.oma.lwm2m+json",
+  "application/vnd.oma.pal+xml",
+  "application/vnd.oma.poc.detailed-progress-report+xml",
+  "application/vnd.oma.poc.final-report+xml",
+  "application/vnd.oma.poc.groups+xml",
+  "application/vnd.oma.poc.invocation-descriptor+xml",
+  "application/vnd.oma.poc.optimized-progress-report+xml",
+  "application/vnd.oma.scidm.messages+xml",
+  "application/vnd.oma.xcap-directory+xml",
+  "application/vnd.omads-email+xml",
+  "application/vnd.omads-file+xml",
+  "application/vnd.omads-folder+xml",
+  "application/vnd.openblox.game+xml",
+  "application/vnd.openstreetmap.data+xml",
+  "application/vnd.openxmlformats-officedocument.custom-properties+xml",
+  "application/vnd.openxmlformats-officedocument.customxmlproperties+xml",
+  "application/vnd.openxmlformats-officedocument.drawing+xml",
+  "application/vnd.openxmlformats-officedocument.drawingml.chart+xml",
+  "application/vnd.openxmlformats-officedocument.drawingml.chartshapes+xml",
+  "application/vnd.openxmlformats-officedocument.drawingml.diagramcolors+xml",
+  "application/vnd.openxmlformats-officedocument.drawingml.diagramdata+xml",
+  "application/vnd.openxmlformats-officedocument.drawingml.diagramlayout+xml",
+  "application/vnd.openxmlformats-officedocument.drawingml.diagramstyle+xml",
+  "application/vnd.openxmlformats-officedocument.extended-properties+xml",
+  "application/vnd.openxmlformats-officedocument.presentationml.commentauthors+xml",
+  "application/vnd.openxmlformats-officedocument.presentationml.comments+xml",
+  "application/vnd.openxmlformats-officedocument.presentationml.handoutmaster+xml",
+  "application/vnd.openxmlformats-officedocument.presentationml.notesmaster+xml",
+  "application/vnd.openxmlformats-officedocument.presentationml.notesslide+xml",
+  "application/vnd.openxmlformats-officedocument.presentationml.presentation.main+xml",
+  "application/vnd.openxmlformats-officedocument.presentationml.presprops+xml",
+  "application/vnd.openxmlformats-officedocument.presentationml.slide+xml",
+  "application/vnd.openxmlformats-officedocument.presentationml.slidelayout+xml",
+  "application/vnd.openxmlformats-officedocument.presentationml.slidemaster+xml",
+  "application/vnd.openxmlformats-officedocument.presentationml.slideshow.main+xml",
+  "application/vnd.openxmlformats-officedocument.presentationml.slideupdateinfo+xml",
+  "application/vnd.openxmlformats-officedocument.presentationml.tablestyles+xml",
+  "application/vnd.openxmlformats-officedocument.presentationml.tags+xml",
+  "application/vnd.openxmlformats-officedocument.presentationml.template.main+xml",
+  "application/vnd.openxmlformats-officedocument.presentationml.viewprops+xml",
+  "application/vnd.openxmlformats-officedocument.spreadsheetml.calcchain+xml",
+  "application/vnd.openxmlformats-officedocument.spreadsheetml.chartsheet+xml",
+  "application/vnd.openxmlformats-officedocument.spreadsheetml.comments+xml",
+  "application/vnd.openxmlformats-officedocument.spreadsheetml.connections+xml",
+  "application/vnd.openxmlformats-officedocument.spreadsheetml.dialogsheet+xml",
+  "application/vnd.openxmlformats-officedocument.spreadsheetml.externallink+xml",
+  "application/vnd.openxmlformats-officedocument.spreadsheetml.pivotcachedefinition+xml",
+  "application/vnd.openxmlformats-officedocument.spreadsheetml.pivotcacherecords+xml",
+  "application/vnd.openxmlformats-officedocument.spreadsheetml.pivottable+xml",
+  "application/vnd.openxmlformats-officedocument.spreadsheetml.querytable+xml",
+  "application/vnd.openxmlformats-officedocument.spreadsheetml.revisionheaders+xml",
+  "application/vnd.openxmlformats-officedocument.spreadsheetml.revisionlog+xml",
+  "application/vnd.openxmlformats-officedocument.spreadsheetml.sharedstrings+xml",
+  "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet.main+xml",
+  "application/vnd.openxmlformats-officedocument.spreadsheetml.sheetmetadata+xml",
+  "application/vnd.openxmlformats-officedocument.spreadsheetml.styles+xml",
+  "application/vnd.openxmlformats-officedocument.spreadsheetml.table+xml",
+  "application/vnd.openxmlformats-officedocument.spreadsheetml.tablesinglecells+xml",
+  "application/vnd.openxmlformats-officedocument.spreadsheetml.template.main+xml",
+  "application/vnd.openxmlformats-officedocument.spreadsheetml.usernames+xml",
+  "application/vnd.openxmlformats-officedocument.spreadsheetml.volatiledependencies+xml",
+  "application/vnd.openxmlformats-officedocument.spreadsheetml.worksheet+xml",
+  "application/vnd.openxmlformats-officedocument.theme+xml",
+  "application/vnd.openxmlformats-officedocument.themeoverride+xml",
+  "application/vnd.openxmlformats-officedocument.wordprocessingml.comments+xml",
+  "application/vnd.openxmlformats-officedocument.wordprocessingml.document.glossary+xml",
+  "application/vnd.openxmlformats-officedocument.wordprocessingml.document.main+xml",
+  "application/vnd.openxmlformats-officedocument.wordprocessingml.endnotes+xml",
+  "application/vnd.openxmlformats-officedocument.wordprocessingml.fonttable+xml",
+  "application/vnd.openxmlformats-officedocument.wordprocessingml.footer+xml",
+  "application/vnd.openxmlformats-officedocument.wordprocessingml.footnotes+xml",
+  "application/vnd.openxmlformats-officedocument.wordprocessingml.numbering+xml",
+  "application/vnd.openxmlformats-officedocument.wordprocessingml.settings+xml",
+  "application/vnd.openxmlformats-officedocument.wordprocessingml.styles+xml",
+  "application/vnd.openxmlformats-officedocument.wordprocessingml.template.main+xml",
+  "application/vnd.openxmlformats-officedocument.wordprocessingml.websettings+xml",
+  "application/vnd.openxmlformats-package.core-properties+xml",
+  "application/vnd.openxmlformats-package.digital-signature-xmlsignature+xml",
+  "application/vnd.openxmlformats-package.relationships+xml",
+  "application/vnd.oracle.resource+json",
+  "application/vnd.otps.ct-kip+xml",
+  "application/vnd.pagerduty+json",
+  "application/vnd.poc.group-advertisement+xml",
+  "application/vnd.pwg-xhtml-print+xml",
+  "application/vnd.radisys.moml+xml",
+  "application/vnd.radisys.msml+xml",
+  "application/vnd.radisys.msml-audit+xml",
+  "application/vnd.radisys.msml-audit-conf+xml",
+  "application/vnd.radisys.msml-audit-conn+xml",
+  "application/vnd.radisys.msml-audit-dialog+xml",
+  "application/vnd.radisys.msml-audit-stream+xml",
+  "application/vnd.radisys.msml-conf+xml",
+  "application/vnd.radisys.msml-dialog+xml",
+  "application/vnd.radisys.msml-dialog-base+xml",
+  "application/vnd.radisys.msml-dialog-fax-detect+xml",
+  "application/vnd.radisys.msml-dialog-fax-sendrecv+xml",
+  "application/vnd.radisys.msml-dialog-group+xml",
+  "application/vnd.radisys.msml-dialog-speech+xml",
+  "application/vnd.radisys.msml-dialog-transform+xml",
+  "application/vnd.recordare.musicxml+xml",
+  "application/vnd.restful+json",
+  "application/vnd.route66.link66+xml",
+  "application/vnd.seis+json",
+  "application/vnd.shootproof+json",
+  "application/vnd.shopkick+json",
+  "application/vnd.siren+json",
+  "application/vnd.software602.filler.form+xml",
+  "application/vnd.solent.sdkm+xml",
+  "application/vnd.sun.wadl+xml",
+  "application/vnd.sycle+xml",
+  "application/vnd.syncml+xml",
+  "application/vnd.syncml.dm+xml",
+  "application/vnd.syncml.dmddf+xml",
+  "application/vnd.syncml.dmtnds+xml",
+  "application/vnd.tableschema+json",
+  "application/vnd.think-cell.ppttc+json",
+  "application/vnd.tmd.mediaflex.api+xml",
+  "application/vnd.uoml+xml",
+  "application/vnd.vel+json",
+  "application/vnd.wv.csp+xml",
+  "application/vnd.wv.ssp+xml",
+  "application/vnd.xacml+json",
+  "application/vnd.xmi+xml",
+  "application/vnd.yamaha.openscoreformat.osfpvg+xml",
+  "application/vnd.zzazz.deck+xml",
+  "application/voicexml+xml",
+  "application/voucher-cms+json",
+  "application/wasm",
+  "application/watcherinfo+xml",
+  "application/webpush-options+json",
+  "application/wsdl+xml",
+  "application/wspolicy+xml",
+  "application/x-dtbncx+xml",
+  "application/x-dtbook+xml",
+  "application/x-dtbresource+xml",
+  "application/x-httpd-php",
+  "application/x-javascript",
+  "application/x-ns-proxy-autoconfig",
+  "application/x-sh",
+  "application/x-tar",
+  "application/x-virtualbox-hdd",
+  "application/x-virtualbox-ova",
+  "application/x-virtualbox-ovf",
+  "application/x-virtualbox-vbox",
+  "application/x-virtualbox-vdi",
+  "application/x-virtualbox-vhd",
+  "application/x-virtualbox-vmdk",
+  "application/x-web-app-manifest+json",
+  "application/x-www-form-urlencoded",
+  "application/x-xliff+xml",
+  "application/xacml+xml",
+  "application/xaml+xml",
+  "application/xcap-att+xml",
+  "application/xcap-caps+xml",
+  "application/xcap-diff+xml",
+  "application/xcap-el+xml",
+  "application/xcap-error+xml",
+  "application/xcap-ns+xml",
+  "application/xcon-conference-info+xml",
+  "application/xcon-conference-info-diff+xml",
+  "application/xenc+xml",
+  "application/xhtml+xml",
+  "application/xhtml-voice+xml",
+  "application/xliff+xml",
+  "application/xml",
+  "application/xml-dtd",
+  "application/xml-patch+xml",
+  "application/xmpp+xml",
+  "application/xop+xml",
+  "application/xproc+xml",
+  "application/xslt+xml",
+  "application/xspf+xml",
+  "application/xv+xml",
+  "application/yang-data+json",
+  "application/yang-data+xml",
+  "application/yang-patch+json",
+  "application/yang-patch+xml",
+  "application/yin+xml",
+  "font/otf",
+  "font/ttf",
+  "image/bmp",
+  "image/svg+xml",
+  "image/vnd.adobe.photoshop",
+  "image/x-icon",
+  "image/x-ms-bmp",
+  "message/imdn+xml",
+  "message/rfc822",
+  "model/gltf+json",
+  "model/gltf-binary",
+  "model/vnd.collada+xml",
+  "model/vnd.moml+xml",
+  "model/x3d+xml",
+  "text/cache-manifest",
+  "text/calender",
+  "text/cmd",
+  "text/css",
+  "text/csv",
+  "text/html",
+  "text/javascript",
+  "text/jsx",
+  "text/less",
+  "text/markdown",
+  "text/mdx",
+  "text/n3",
+  "text/plain",
+  "text/richtext",
+  "text/rtf",
+  "text/tab-separated-values",
+  "text/uri-list",
+  "text/vcard",
+  "text/vtt",
+  "text/x-gwt-rpc",
+  "text/x-jquery-tmpl",
+  "text/x-markdown",
+  "text/x-org",
+  "text/x-processing",
+  "text/x-suse-ymp",
+  "text/xml",
+  "text/yaml",
+  "x-shader/x-fragment",
+  "x-shader/x-vertex",
+];
+
+/// Determine if the supplied content type is considered compressible
+pub fn is_content_compressible(
+  maybe_content_type: Option<&ByteString>,
+) -> bool {
+  if let Some(content_type) = maybe_content_type {
+    if let Ok(content_type) = std::str::from_utf8(content_type.as_ref()) {
+      if let Ok(content_type) = content_type.parse::<mime::Mime>() {
+        return CONTENT_TYPES
+          .binary_search(&content_type.essence_str())
+          .is_ok();
+      }
+    }
+  }
+  false
+}
+
+#[cfg(test)]
+mod tests {
+  use super::*;
+
+  #[test]
+  fn content_type_none() {
+    assert!(!is_content_compressible(None));
+  }
+
+  #[test]
+  fn non_compressible_content_type() {
+    assert!(!is_content_compressible(Some(&ByteString(
+      b"application/vnd.deno+json".to_vec()
+    ))));
+  }
+
+  #[test]
+  fn ncompressible_content_type() {
+    assert!(is_content_compressible(Some(&ByteString(
+      b"application/json".to_vec()
+    ))));
+  }
+}
diff --git a/ext/http/lib.rs b/ext/http/lib.rs
index 312942303..b70bed464 100644
--- a/ext/http/lib.rs
+++ b/ext/http/lib.rs
@@ -1,6 +1,7 @@
 // Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
 
 use bytes::Bytes;
+use cache_control::CacheControl;
 use deno_core::error::custom_error;
 use deno_core::error::AnyError;
 use deno_core::futures::channel::mpsc;
@@ -34,6 +35,9 @@ use deno_core::ResourceId;
 use deno_core::StringOrBuffer;
 use deno_core::ZeroCopyBuf;
 use deno_websocket::ws_create_server_stream;
+use flate2::write::GzEncoder;
+use flate2::Compression;
+use fly_accept_encoding::Encoding;
 use hyper::server::conn::Http;
 use hyper::service::Service;
 use hyper::Body;
@@ -47,6 +51,7 @@ use std::cmp::min;
 use std::error::Error;
 use std::future::Future;
 use std::io;
+use std::io::Write;
 use std::mem::replace;
 use std::mem::take;
 use std::pin::Pin;
@@ -58,6 +63,8 @@ use tokio::io::AsyncRead;
 use tokio::io::AsyncWrite;
 use tokio::task::spawn_local;
 
+mod compressible;
+
 pub fn init() -> Extension {
   Extension::builder()
     .js(include_js_files!(
@@ -292,6 +299,7 @@ struct HttpStreamResource {
   conn: Rc<HttpConnResource>,
   rd: AsyncRefCell<HttpRequestReader>,
   wr: AsyncRefCell<HttpResponseWriter>,
+  accept_encoding: RefCell<Encoding>,
   cancel_handle: CancelHandle,
 }
 
@@ -305,6 +313,7 @@ impl HttpStreamResource {
       conn: conn.clone(),
       rd: HttpRequestReader::Headers(request).into(),
       wr: HttpResponseWriter::Headers(response_tx).into(),
+      accept_encoding: RefCell::new(Encoding::Identity),
       cancel_handle: CancelHandle::new(),
     }
   }
@@ -381,6 +390,14 @@ async fn op_http_accept(
     _ => unreachable!(),
   };
 
+  {
+    let mut accept_encoding = stream.accept_encoding.borrow_mut();
+    *accept_encoding = fly_accept_encoding::parse(request.headers())
+      .ok()
+      .flatten()
+      .unwrap_or(Encoding::Identity);
+  }
+
   let method = request.method().to_string();
   let headers = req_headers(request);
   let url = req_url(request, conn.scheme(), conn.addr());
@@ -497,22 +514,164 @@ async fn op_http_write_headers(
 
   let mut builder = Response::builder().status(status);
 
+  let mut body_compressible = false;
+  let mut headers_allow_compression = true;
+  let mut vary_header = None;
+  let mut etag_header = None;
+  let mut content_type_header = None;
+
   builder.headers_mut().unwrap().reserve(headers.len());
   for (key, value) in &headers {
+    match &*key.to_ascii_lowercase() {
+      b"cache-control" => {
+        if let Ok(value) = std::str::from_utf8(value) {
+          if let Some(cache_control) = CacheControl::from_value(value) {
+            // We skip compression if the cache-control header value is set to
+            // "no-transform"
+            if cache_control.no_transform {
+              headers_allow_compression = false;
+            }
+          }
+        } else {
+          headers_allow_compression = false;
+        }
+      }
+      b"content-range" => {
+        // we skip compression if the `content-range` header value is set, as it
+        // indicates the contents of the body were negotiated based directly
+        // with the user code and we can't compress the response
+        headers_allow_compression = false;
+      }
+      b"content-type" => {
+        if !value.is_empty() {
+          content_type_header = Some(value);
+        }
+      }
+      b"content-encoding" => {
+        // we don't compress if a content-encoding header was provided
+        headers_allow_compression = false;
+      }
+      // we store the values of ETag and Vary and skip adding them for now, as
+      // we may need to modify or change.
+      b"etag" => {
+        if !value.is_empty() {
+          etag_header = Some(value);
+          continue;
+        }
+      }
+      b"vary" => {
+        if !value.is_empty() {
+          vary_header = Some(value);
+          continue;
+        }
+      }
+      _ => {}
+    }
     builder = builder.header(key.as_ref(), value.as_ref());
   }
 
+  if headers_allow_compression {
+    body_compressible =
+      compressible::is_content_compressible(content_type_header);
+  }
+
   let body: Response<Body>;
   let new_wr: HttpResponseWriter;
 
   match data {
     Some(data) => {
-      // If a buffer was passed, we use it to construct a response body.
-      body = builder.body(data.into_bytes().into())?;
+      // Set Vary: Accept-Encoding header for direct body response.
+      // Note: we set the header irrespective of whether or not we compress the
+      // data to make sure cache services do not serve uncompressed data to
+      // clients that support compression.
+      let vary_value = if let Some(value) = vary_header {
+        if let Ok(value_str) = std::str::from_utf8(value.as_ref()) {
+          if !value_str.to_lowercase().contains("accept-encoding") {
+            format!("Accept-Encoding, {}", value_str)
+          } else {
+            value_str.to_string()
+          }
+        } else {
+          // the header value wasn't valid UTF8, so it would have been a
+          // problem anyways, so sending a default header.
+          "Accept-Encoding".to_string()
+        }
+      } else {
+        "Accept-Encoding".to_string()
+      };
+      builder = builder.header("vary", &vary_value);
+
+      let accepts_compression = matches!(
+        *stream.accept_encoding.borrow(),
+        Encoding::Brotli | Encoding::Gzip
+      );
+
+      let should_compress =
+        body_compressible && data.len() > 20 && accepts_compression;
+
+      if should_compress {
+        // If user provided a ETag header for uncompressed data, we need to
+        // ensure it is a Weak Etag header ("W/").
+        if let Some(value) = etag_header {
+          if let Ok(value_str) = std::str::from_utf8(value.as_ref()) {
+            if !value_str.starts_with("W/") {
+              builder = builder.header("etag", format!("W/{}", value_str));
+            } else {
+              builder = builder.header("etag", value.as_ref());
+            }
+          } else {
+            builder = builder.header("etag", value.as_ref());
+          }
+        }
+
+        match *stream.accept_encoding.borrow() {
+          Encoding::Brotli => {
+            builder = builder.header("content-encoding", "br");
+            // quality level 6 is based on google's nginx default value for
+            // on-the-fly compression
+            // https://github.com/google/ngx_brotli#brotli_comp_level
+            // lgwin 22 is equivalent to brotli window size of (2**22)-16 bytes
+            // (~4MB)
+            let mut writer =
+              brotli::CompressorWriter::new(Vec::new(), 4096, 6, 22);
+            writer.write_all(&data.into_bytes())?;
+            body = builder.body(writer.into_inner().into())?;
+          }
+          _ => {
+            assert_eq!(*stream.accept_encoding.borrow(), Encoding::Gzip);
+            builder = builder.header("content-encoding", "gzip");
+            // Gzip, after level 1, doesn't produce significant size difference.
+            // Probably the reason why nginx's default gzip compression level is
+            // 1.
+            // https://nginx.org/en/docs/http/ngx_http_gzip_module.html#gzip_comp_level
+            let mut writer = GzEncoder::new(Vec::new(), Compression::new(1));
+            writer.write_all(&data.into_bytes())?;
+            body = builder.body(writer.finish().unwrap().into())?;
+          }
+        }
+      } else {
+        if let Some(value) = etag_header {
+          builder = builder.header("etag", value.as_ref());
+        }
+        // If a buffer was passed, but isn't compressible, we use it to
+        // construct a response body.
+        body = builder.body(data.into_bytes().into())?;
+      }
       new_wr = HttpResponseWriter::Closed;
     }
     None => {
       // If no buffer was passed, the caller will stream the response body.
+
+      // TODO(@kitsonk) had compression for streamed bodies.
+
+      // Set the user provided ETag & Vary headers for a streaming response
+      if let Some(value) = etag_header {
+        builder = builder.header("etag", value.as_ref());
+      }
+      if let Some(value) = vary_header {
+        builder = builder.header("vary", value.as_ref());
+      }
+
       let (body_tx, body_rx) = Body::channel();
       body = builder.body(body_rx)?;
       new_wr = HttpResponseWriter::Body(body_tx);