Add env variable ADD_TEMPLATE (#295 )

Update readme file and CI
feat: Add HTML/CSS/JS minification on the fly (#293 )
2024-08-30 18:22:40 +00:00 · 2024-07-06 14:01:17 +04:00 · 2024-07-05 19:03:08 +04:00 · 2024-07-05 18:59:07 +04:00 · 2024-07-05 14:01:06 +04:00 · 2024-07-05 13:10:41 +04:00
17 changed files with 494 additions and 218 deletions
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@ -36,7 +36,7 @@ jobs:
          tag: ${{ github.ref }}

      - if: matrix.os == 'linux' && matrix.arch == 'amd64'
-        run: mkdir ./out && ./${{ steps.values.outputs.binary-name }} build --index --target-dir ./out
+        run: mkdir ./out && ./${{ steps.values.outputs.binary-name }} build --index --disable-minification --target-dir ./out
      - if: matrix.os == 'linux' && matrix.arch == 'amd64'
        uses: actions/upload-artifact@v4
        with:
@ -93,13 +93,12 @@ jobs:
          push: true
          platforms: linux/amd64,linux/arm/v7,linux/arm64/v8
          build-args: "APP_VERSION=${{ steps.slug.outputs.version }}"
-          tags: ghcr.io/${{ github.actor }}/${{ github.event.repository.name }}:${{ steps.slug.outputs.version }}
-#         tags: | # TODO: uncomment after the stable release
-#           tarampampam/error-pages:latest
-#           tarampampam/error-pages:${{ steps.slug.outputs.version }}
-#           tarampampam/error-pages:${{ steps.slug.outputs.version-major }}.${{ steps.slug.outputs.version-minor }}
-#           tarampampam/error-pages:${{ steps.slug.outputs.version-major }}
-#           ghcr.io/${{ github.actor }}/${{ github.event.repository.name }}:latest
-#           ghcr.io/${{ github.actor }}/${{ github.event.repository.name }}:${{ steps.slug.outputs.version }}
-#           ghcr.io/${{ github.actor }}/${{ github.event.repository.name }}:${{ steps.slug.outputs.version-major }}.${{ steps.slug.outputs.version-minor }}
-#           ghcr.io/${{ github.actor }}/${{ github.event.repository.name }}:${{ steps.slug.outputs.version-major }}
+          tags: |
+            tarampampam/error-pages:latest
+            tarampampam/error-pages:${{ steps.slug.outputs.version }}
+            tarampampam/error-pages:${{ steps.slug.outputs.version-major }}.${{ steps.slug.outputs.version-minor }}
+            tarampampam/error-pages:${{ steps.slug.outputs.version-major }}
+            ghcr.io/${{ github.actor }}/${{ github.event.repository.name }}:latest
+            ghcr.io/${{ github.actor }}/${{ github.event.repository.name }}:${{ steps.slug.outputs.version }}
+            ghcr.io/${{ github.actor }}/${{ github.event.repository.name }}:${{ steps.slug.outputs.version-major }}.${{ steps.slug.outputs.version-minor }}
+            ghcr.io/${{ github.actor }}/${{ github.event.repository.name }}:${{ steps.slug.outputs.version-major }}
--- a/25
+++ b/25
@ -3,7 +3,7 @@
 # -✂- this stage is used to develop and build the application locally -------------------------------------------------
 FROM docker.io/library/golang:1.22-bookworm AS develop

-# use the /var/tmp as the GOPATH to reuse the modules cache
+# use the /var/tmp/go as the GOPATH to reuse the modules cache
 ENV GOPATH="/var/tmp/go"

 RUN set -x \
@ -32,7 +32,10 @@ FROM develop AS compile
 # can be passed with any prefix (like `v1.2.3@GITHASH`), e.g.: `docker build --build-arg "APP_VERSION=v1.2.3" .`
 ARG APP_VERSION="undefined@docker"

-RUN --mount=type=bind,source=.,target=/src set -x \
+# copy the source code
+COPY . /src
+
+RUN set -x \
    && go generate ./... \
    && CGO_ENABLED=0 LDFLAGS="-s -w -X gh.tarampamp.am/error-pages/internal/appmeta.version=${APP_VERSION}" \
      go build -trimpath -ldflags "${LDFLAGS}" -o /tmp/error-pages ./cmd/error-pages/ \
@ -45,10 +48,11 @@ FROM docker.io/library/alpine:3.20 AS rootfs
 WORKDIR /tmp/rootfs

 # prepare rootfs for runtime
-RUN --mount=type=bind,source=.,target=/src set -x \
-    && mkdir -p ./etc ./bin \
+RUN set -x \
+    && mkdir -p ./etc/ssl/certs ./bin \
    && echo 'appuser:x:10001:10001::/nonexistent:/sbin/nologin' > ./etc/passwd \
-    && echo 'appuser:x:10001:' > ./etc/group
+    && echo 'appuser:x:10001:' > ./etc/group \
+    && cp /etc/ssl/certs/ca-certificates.crt ./etc/ssl/certs/

 # take the binary from the compile stage
 COPY --from=compile /tmp/error-pages ./bin/error-pages
@ -69,7 +73,7 @@ ARG APP_VERSION="undefined@docker"
 LABEL \
    # docs: https://github.com/opencontainers/image-spec/blob/master/annotations.md
    org.opencontainers.image.title="error-pages" \
-    org.opencontainers.image.description="Static server error pages in the docker image" \
+    org.opencontainers.image.description="Pretty server's error pages" \
    org.opencontainers.image.url="https://github.com/tarampampam/error-pages" \
    org.opencontainers.image.source="https://github.com/tarampampam/error-pages" \
    org.opencontainers.image.vendor="tarampampam" \
@ -87,13 +91,12 @@ WORKDIR /opt
 # to find out which environment variables and CLI arguments are supported by the application, run the app
 # with the `--help` flag or refer to the documentation at https://github.com/tarampampam/error-pages#readme

-ENV LOG_LEVEL="warn"
+ENV LOG_LEVEL="warn" \
+    LOG_FORMAT="json"

 # docs: https://docs.docker.com/reference/dockerfile/#healthcheck
-HEALTHCHECK --interval=10s --start-interval=1s --start-period=5s --timeout=2s CMD [\
-  "/bin/error-pages", "--log-format", "json", "healthcheck" \
-]
+HEALTHCHECK --interval=10s --start-interval=1s --start-period=5s --timeout=2s CMD ["/bin/error-pages", "healthcheck"]

 ENTRYPOINT ["/bin/error-pages"]

-CMD ["--log-format", "json", "serve"]
+CMD ["serve"]
--- a/README.md
+++ b/README.md
@ -1,5 +1,10 @@
 <p align="center">
-  <a href="https://github.com/tarampampam/error-pages#readme"><img src="https://socialify.git.ci/tarampampam/error-pages/image?description=1&font=Raleway&forks=1&issues=1&logo=https%3A%2F%2Fhsto.org%2Fwebt%2Frm%2F9y%2Fww%2Frm9ywwx3gjv9agwkcmllhsuyo7k.png&owner=1&pulls=1&pattern=Solid&stargazers=1&theme=Dark" alt="banner" width="100%" /></a>
+  <a href="https://github.com/tarampampam/error-pages#readme">
+    <picture>
+      <source media="(prefers-color-scheme: dark)" srcset="https://socialify.git.ci/tarampampam/error-pages/image?description=1&font=Raleway&forks=1&issues=1&logo=https%3A%2F%2Fhsto.org%2Fwebt%2Frm%2F9y%2Fww%2Frm9ywwx3gjv9agwkcmllhsuyo7k.png&owner=1&pulls=1&pattern=Solid&stargazers=1&theme=Dark">
+      <img align="center" src="https://socialify.git.ci/tarampampam/error-pages/image?description=1&font=Raleway&forks=1&issues=1&logo=https%3A%2F%2Fhsto.org%2Fwebt%2Frm%2F9y%2Fww%2Frm9ywwx3gjv9agwkcmllhsuyo7k.png&owner=1&pulls=1&pattern=Solid&stargazers=1&theme=Light">
+    </picture>
+  </a>
 </p>

 <p align="center">
@ -15,21 +20,25 @@ One day, you might want to replace the standard error pages of your HTTP server
 original and attractive. That's why this repository was created :) It contains:

 - A simple error page generator written in Go
- Single-page error templates (themes) with various designs (located in the [templates](templates) directory) that
+- Single-page error templates (themes) with various designs (located in the [templates][templates-dir] directory) that
  you can customize as you wish
 - A fast and lightweight HTTP server is available as a single binary file and Docker image. It includes built-in error
  page templates from this repository. You don't need anything except the compiled binary file or Docker image
- Pre-generated error pages (sources can be [found here][preview-sources], and the **demo** is always
-  accessible [here][preview-demo])
+- Pre-generated error pages (sources can be [found here][preview-sources], and the [**demo** is always
+  accessible here][preview-demo])

 [preview-sources]:https://github.com/tarampampam/error-pages/tree/gh-pages
 [preview-demo]:https://tarampampam.github.io/error-pages/
+[templates-dir]:https://github.com/tarampampam/error-pages/tree/master/templates

 ## 🔥 Features List

 - HTTP server written in Go, utilizing the extremely fast [FastHTTP][fasthttp] and in-memory caching
  - Respects the `Content-Type` HTTP header (and `X-Format`) value, responding with the corresponding format
    (supported formats: `json`, `xml`, and `plaintext`)
+  - Error pages are configured to be excluded from search engine indexing (using meta tags and HTTP headers) to
+    prevent SEO issues on your website
+  - HTML content (including CSS, SVG, and JS) is minified on the fly
  - Logs written in `json` format
  - Contains a health check endpoint (`/healthz`)
  - Consumes very few resources and is suitable for use in resource-constrained environments
@ -40,10 +49,11 @@ original and attractive. That's why this repository was created :) It contains:
 - Fully configurable
 - Distributed as a Docker image and compiled binary files
 - Localized HTML error pages (🇺🇸, 🇫🇷, 🇺🇦, 🇷🇺, 🇵🇹, 🇳🇱, 🇩🇪, 🇪🇸, 🇨🇳, 🇮🇩, 🇵🇱) - translation process
-  [described here](l10n) - other translations are welcome!
+  [described here][l10n-dir] - other translations are welcome!

 [fasthttp]:https://github.com/valyala/fasthttp
 [traefik]:https://github.com/traefik/traefik
+[l10n-dir]:https://github.com/tarampampam/error-pages/tree/master/l10n

 ## 🧩 Install

@ -67,6 +77,189 @@ Download the latest binary file for your OS/architecture from the [releases page
 [pages-pack-zip]:https://github.com/tarampampam/error-pages/zipball/gh-pages/
 [pages-pack-tar-gz]:https://github.com/tarampampam/error-pages/tarball/gh-pages/

+## 🪂 Templates (themes)
+
+The following templates are built-in and available for use without any additional setup:
+
+> [!NOTE]
+> The `cats` template is the only one of those that fetches resources (the actual cat pictures) from external
+> servers - all other templates are self-contained.
+
+<table>
+  <thead>
+    <tr>
+      <th>Template</th>
+      <th>Preview</th>
+    </tr>
+  </thead>
+  <tbody>
+    <tr>
+      <td align="center">
+        <code>app-down</code><br/><br/>
+        <picture>
+          <img src="https://img.shields.io/badge/dynamic/json?url=https%3A%2F%2Ferror-pages.goatcounter.com%2Fcounter%2F%2Fuse-template%2Fapp-down.json&query=%24.count&label=used%20times" alt="used times">
+        </picture>
+      </td>
+      <td>
+        <a href="https://tarampampam.github.io/error-pages/app-down/404.html">
+          <picture>
+            <source media="(prefers-color-scheme: dark)" srcset="https://github.com/tarampampam/error-pages/assets/7326800/4e668a56-a4c4-47cd-ac4d-b6b45db54ab8">
+            <img align="center" src="https://github.com/tarampampam/error-pages/assets/7326800/ad4b4fd7-7c7b-4bdc-a6b6-44f9ba7f77ca">
+          </picture>
+        </a>
+      </td>
+    </tr>
+    <tr>
+      <td align="center">
+        <code>cats</code><br/><br/>
+        <picture>
+          <img src="https://img.shields.io/badge/dynamic/json?url=https%3A%2F%2Ferror-pages.goatcounter.com%2Fcounter%2F%2Fuse-template%2Fcats.json&query=%24.count&label=used%20times" alt="used times">
+        </picture>
+      </td>
+      <td>
+        <a href="https://tarampampam.github.io/error-pages/cats/404.html">
+          <picture>
+            <source media="(prefers-color-scheme: dark)" srcset="https://github.com/tarampampam/error-pages/assets/7326800/5689880b-f770-406c-81dd-2d28629e6f2e">
+            <img align="center" src="https://github.com/tarampampam/error-pages/assets/7326800/056cd00e-bc9a-4120-8325-310d7b0ebd1b">
+          </picture>
+        </a>
+      </td>
+    </tr>
+    <tr>
+      <td align="center">
+        <code>connection</code><br/><br/>
+        <picture>
+          <img src="https://img.shields.io/badge/dynamic/json?url=https%3A%2F%2Ferror-pages.goatcounter.com%2Fcounter%2F%2Fuse-template%2Fconnection.json&query=%24.count&label=used%20times" alt="used times">
+        </picture>
+      </td>
+      <td>
+        <a href="https://tarampampam.github.io/error-pages/connection/404.html">
+          <picture>
+            <source media="(prefers-color-scheme: dark)" srcset="https://github.com/tarampampam/error-pages/assets/7326800/3f03dc1b-c1ee-4a91-b3d7-e3b93c79020e">
+            <img align="center" src="https://github.com/tarampampam/error-pages/assets/7326800/099ecc2d-e724-4d9c-b5ed-66ddabd71139">
+          </picture>
+        </a>
+      </td>
+    </tr>
+    <tr>
+      <td align="center">
+        <code>ghost</code><br/><br/>
+        <picture>
+          <img src="https://img.shields.io/badge/dynamic/json?url=https%3A%2F%2Ferror-pages.goatcounter.com%2Fcounter%2F%2Fuse-template%2Fghost.json&query=%24.count&label=used%20times" alt="used times">
+        </picture>
+      </td>
+      <td>
+        <a href="https://tarampampam.github.io/error-pages/ghost/404.html">
+          <picture>
+            <source media="(prefers-color-scheme: dark)" srcset="https://github.com/tarampampam/error-pages/assets/7326800/714482ab-f8c1-4455-8ae8-b2ae78f7a2c6">
+            <img align="center" src="https://github.com/tarampampam/error-pages/assets/7326800/f253dfe7-96a0-4e96-915b-d4c544d4a237">
+          </picture>
+        </a>
+      </td>
+    </tr>
+    <tr>
+      <td align="center">
+        <code>hacker-terminal</code><br/><br/>
+        <picture>
+          <img src="https://img.shields.io/badge/dynamic/json?url=https%3A%2F%2Ferror-pages.goatcounter.com%2Fcounter%2F%2Fuse-template%2Fhacker-terminal.json&query=%24.count&label=used%20times" alt="used times">
+        </picture>
+      </td>
+      <td>
+        <a href="https://tarampampam.github.io/error-pages/hacker-terminal/404.html">
+          <picture>
+            <img align="center" src="https://github.com/tarampampam/error-pages/assets/7326800/c197fc35-0844-43d0-9830-82440cee4559">
+          </picture>
+        </a>
+      </td>
+    </tr>
+    <tr>
+      <td align="center">
+        <code>l7</code><br/><br/>
+        <picture>
+          <img src="https://img.shields.io/badge/dynamic/json?url=https%3A%2F%2Ferror-pages.goatcounter.com%2Fcounter%2F%2Fuse-template%2Fl7.json&query=%24.count&label=used%20times" alt="used times">
+        </picture>
+      </td>
+      <td>
+        <a href="https://tarampampam.github.io/error-pages/l7/404.html">
+          <picture>
+            <source media="(prefers-color-scheme: dark)" srcset="https://github.com/tarampampam/error-pages/assets/7326800/18e43ea3-6389-4459-be41-0fc6566a073f">
+            <img align="center" src="https://github.com/tarampampam/error-pages/assets/7326800/05f26669-94ec-40ce-8d67-a199cde54202">
+          </picture>
+        </a>
+      </td>
+    </tr>
+    <tr>
+      <td align="center">
+        <code>lost-in-space</code><br/><br/>
+        <picture>
+          <img src="https://img.shields.io/badge/dynamic/json?url=https%3A%2F%2Ferror-pages.goatcounter.com%2Fcounter%2F%2Fuse-template%2Flost-in-space.json&query=%24.count&label=used%20times" alt="used times">
+        </picture>
+      </td>
+      <td>
+        <a href="https://tarampampam.github.io/error-pages/lost-in-space/404.html">
+          <picture>
+            <source media="(prefers-color-scheme: dark)" srcset="https://github.com/tarampampam/error-pages/assets/7326800/debf87c0-6f27-41a8-b141-ee3464cbd6cc">
+            <img align="center" src="https://github.com/tarampampam/error-pages/assets/7326800/c347e63d-13a7-46d4-81b9-b25266819a1d">
+          </picture>
+        </a>
+      </td>
+    </tr>
+    <tr>
+      <td align="center">
+        <code>noise</code><br/><br/>
+        <picture>
+          <img src="https://img.shields.io/badge/dynamic/json?url=https%3A%2F%2Ferror-pages.goatcounter.com%2Fcounter%2F%2Fuse-template%2Fnoise.json&query=%24.count&label=used%20times" alt="used times">
+        </picture>
+      </td>
+      <td>
+        <a href="https://tarampampam.github.io/error-pages/noise/404.html">
+          <picture>
+            <img align="center" src="https://github.com/tarampampam/error-pages/assets/7326800/4cc5c3bd-6ebb-4e96-bee8-02d4ad4e7266">
+          </picture>
+        </a>
+      </td>
+    </tr>
+    <tr>
+      <td align="center">
+        <code>orient</code><br/><br/>
+        <picture>
+          <img src="https://img.shields.io/badge/dynamic/json?url=https%3A%2F%2Ferror-pages.goatcounter.com%2Fcounter%2F%2Fuse-template%2Forient.json&query=%24.count&label=used%20times" alt="used times">
+        </picture>
+      </td>
+      <td>
+        <a href="https://tarampampam.github.io/error-pages/orient/404.html">
+          <picture>
+            <source media="(prefers-color-scheme: dark)" srcset="https://github.com/tarampampam/error-pages/assets/7326800/bc2b0dad-c32c-4628-98f6-e3eab61dd1f2">
+            <img align="center" src="https://github.com/tarampampam/error-pages/assets/7326800/8fc0a7ea-694d-49ce-bb50-3ea032d52d1e">
+          </picture>
+        </a>
+      </td>
+    </tr>
+    <tr>
+      <td align="center">
+        <code>shuffle</code><br/><br/>
+        <picture>
+          <img src="https://img.shields.io/badge/dynamic/json?url=https%3A%2F%2Ferror-pages.goatcounter.com%2Fcounter%2F%2Fuse-template%2Fshuffle.json&query=%24.count&label=used%20times" alt="used times">
+        </picture>
+      </td>
+      <td>
+        <a href="https://tarampampam.github.io/error-pages/shuffle/404.html">
+          <picture>
+            <source media="(prefers-color-scheme: dark)" srcset="https://github.com/tarampampam/error-pages/assets/7326800/7504b7c3-b0cb-4991-9ac2-759cd6c50fc0">
+            <img align="center" src="https://github.com/tarampampam/error-pages/assets/7326800/d2a73fc8-cf5f-4f42-bff8-cce33d8ae47e">
+          </picture>
+        </a>
+      </td>
+    </tr>
+  </tbody>
+</table>
+
+> [!NOTE]
+> The "used times" counter increments when someone start the server with the specified template. Stats service does
+> not collect any information about location, IP addresses, and so on. Moreover, the stats are open and available for
+> everyone at [error-pages.goatcounter.com](https://error-pages.goatcounter.com/). This is simply a counter to display
+> how often a particular template is used, nothing more.
+
 ## 🛠 Usage scenarios

 ### HTTP server starting, utilizing either a binary file or Docker image
@ -75,9 +268,9 @@ First, ensure you have a precompiled binary file on your machine or have Docker/
 server with the following command:

 ```bash
-./error-pages serve
-# or
-docker run --rm -p '8080:8080/tcp' tarampampam/error-pages serve
+$ ./error-pages serve
+# --- or ---
+$ docker run --rm -p '8080:8080/tcp' tarampampam/error-pages serve
 ```

 That's it! The server will begin running and listen on address `0.0.0.0` and port `8080`. Access error pages using
@ -86,7 +279,7 @@ URLs like `http://127.0.0.1:8080/{page_code}.html`.
 To retrieve different error page codes using a static URL, use the `X-Code` HTTP header:

 ```bash
-curl -H 'X-Code: 500' http://127.0.0.1:8080/
+$ curl -H 'X-Code: 500' http://127.0.0.1:8080/
 ```

 The server respects the `Content-Type` HTTP header (and `X-Format`), delivering responses in requested formats
@ -108,6 +301,55 @@ are detailed in the readme file below.
 To proxy HTTP headers from requests to responses, utilize the `--proxy-headers` flag or environment variable
 (comma-separated list of headers).

+<details>
+  <summary><strong>🚀 Start the HTTP server with my custom template (theme)</strong></summary>
+
+First, create your own template file, for example `my-super-theme.html`:
+
+```html
+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <title>{{ code }}</title>
+</head>
+<body>
+  <h1>YEAH! {{ message }}: {{ description }}</h1>
+</body>
+</html>
+```
+
+And simply start the server with the following command:
+
+```bash
+$ docker run --rm \
+  -v "$(pwd)/my-super-theme.html:/opt/my-template.html:ro" \
+  -p '8080:8080/tcp' ghcr.io/tarampampam/error-pages:3 serve \
+    --add-template /opt/my-template.html \
+    --template-name my-template
+# --- or ---
+$ ./error-pages serve \
+  --add-template /opt/my-template.html \
+  --template-name my-template
+```
+
+And test it:
+
+```bash
+$ curl -H "Accept: text/html" http://127.0.0.1:8080/503
+
+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <title>503</title>
+</head>
+<body>
+  <h1>YEAH! Service Unavailable: The server is temporarily overloading or down</h1>
+</body>
+</html>
+```
+
+</details>
+
 <details>
  <summary><strong>🚀 Generate a set of error pages using built-in or my own template</strong></summary>

@ -129,8 +371,8 @@ Create a file like this:
 Save it as `my-template.html` and use it as your custom template. Then, generate your error pages using the command:

 ```bash
-mkdir -p /path/to/output
-./error-pages build --add-template /path/to/your/my-template.html --target-dir /path/to/output
+$ mkdir -p /path/to/output
+$ ./error-pages build --add-template /path/to/your/my-template.html --target-dir /path/to/output
 ```

 This will create error pages based on your template in the specified output directory:
@ -228,14 +470,15 @@ COPY --chown=nginx \
 Now, we can build the image:

 ```bash
-docker build --tag your-nginx:local -f ./Dockerfile .
+$ docker build --tag your-nginx:local -f ./Dockerfile .
 ```

 And voilà! Let's start the image and test if everything is working as expected:

 ```bash
-docker run --rm -p '8081:80/tcp' your-nginx:local
-curl http://127.0.0.1:8081/foobar | head -n 15 # in another terminal
+$ docker run --rm -p '8081:80/tcp' your-nginx:local
+
+$ curl http://127.0.0.1:8081/foobar | head -n 15 # in another terminal
 ```

 </details>
@ -325,6 +568,7 @@ controller:
  config:
    custom-http-errors: >-
      401,403,404,500,501,502,503
+
 defaultBackend:
  enabled: true
  image:
@ -367,11 +611,11 @@ Test completed successfully. Here is the output:
 Running 15s test @ http://127.0.0.1:8080/
  12 threads and 400 connections
  Thread Stats   Avg      Stdev     Max   +/- Stdev
-    Latency     3.54ms    4.90ms  74.57ms   86.55%
-    Req/Sec    16.47k     2.89k   38.11k    69.46%
-  2967567 requests in 15.09s, 44.70GB read
-Requests/sec: 196596.49
-Transfer/sec:      2.96GB
+    Latency     4.52ms    6.43ms  94.34ms   85.44%
+    Req/Sec    15.76k     2.83k   29.64k    69.20%
+  2839632 requests in 15.09s, 32.90GB read
+Requests/sec: 188185.61
+Transfer/sec:      2.18GB

 Starting the test to bomb DIFFERENT PAGES (codes). Please, be patient...
 Test completed successfully. Here is the output:
@ -379,11 +623,11 @@ Test completed successfully. Here is the output:
 Running 15s test @ http://127.0.0.1:8080/
  12 threads and 400 connections
  Thread Stats   Avg      Stdev     Max   +/- Stdev
-    Latency     4.25ms    6.03ms  74.23ms   86.97%
-    Req/Sec    14.29k     2.75k   32.16k    69.63%
-  2563245 requests in 15.07s, 38.47GB read
-Requests/sec: 170062.69
-Transfer/sec:      2.55GB
+    Latency     6.75ms   13.71ms 252.66ms   91.94%
+    Req/Sec    14.06k     3.25k   26.39k    71.98%
+  2534473 requests in 15.10s, 29.22GB read
+Requests/sec: 167899.78
+Transfer/sec:      1.94GB
 ```

 </details>
@ -421,7 +665,7 @@ The following flags are supported:
 |------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|:-----------------------------------------:|:---------------------------:|
 | `--listen="…"` (`-l`)        | The HTTP server will listen on this IP (v4 or v6) address (set 127.0.0.1/::1 for localhost, 0.0.0.0 to listen on all interfaces, or specify a custom IP)                                                                                                                                                                  |                 `0.0.0.0`                 |        `LISTEN_ADDR`        |
 | `--port="…"` (`-p`)          | The TCP port number for the HTTP server to listen on (0-65535)                                                                                                                                                                                                                                                            |                  `8080`                   |        `LISTEN_PORT`        |
-| `--add-template="…"`         | To add a new template, provide the path to the file using this flag (the filename without the extension will be used as the template name)                                                                                                                                                                                |                   `[]`                    |           *none*            |
+| `--add-template="…"`         | To add a new template, provide the path to the file using this flag (the filename without the extension will be used as the template name)                                                                                                                                                                                |                   `[]`                    |       `ADD_TEMPLATE`        |
 | `--disable-template="…"`     | Disable the specified template by its name (useful to disable the built-in templates and use only custom ones)                                                                                                                                                                                                            |                   `[]`                    |           *none*            |
 | `--add-code="…"`             | To add a new HTTP status code, provide the code and its message/description using this flag (the format should be '%code%=%message%/%description%'; the code may contain a wildcard '*' to cover multiple codes at once, for example, '4**' will cover all 4xx codes unless a more specific code is described previously) |                  `map[]`                  |           *none*            |
 | `--json-format="…"`          | Override the default error page response in JSON format (Go templates are supported; the error page will use this template if the client requests JSON content type)                                                                                                                                                      |                                           |   `RESPONSE_JSON_FORMAT`    |
@ -435,6 +679,7 @@ The following flags are supported:
 | `--proxy-headers="…"`        | HTTP headers listed here will be proxied from the original request to the error page response (comma-separated list)                                                                                                                                                                                                      | `X-Request-Id,X-Trace-Id,X-Amzn-Trace-Id` |    `PROXY_HTTP_HEADERS`     |
 | `--rotation-mode="…"`        | Templates automatic rotation mode (disabled/random-on-startup/random-on-each-request/random-hourly/random-daily)                                                                                                                                                                                                          |                `disabled`                 |  `TEMPLATES_ROTATION_MODE`  |
 | `--read-buffer-size="…"`     | Per-connection buffer size in bytes for reading requests, this also limits the maximum header size (increase this buffer if your clients send multi-KB Request URIs and/or multi-KB headers (e.g., large cookies), note that increasing this value will increase memory consumption)                                      |                  `5120`                   |     `READ_BUFFER_SIZE`      |
+| `--disable-minification`     | Disable the minification of HTML pages, including CSS, SVG, and JS (may be useful for debugging)                                                                                                                                                                                                                          |                  `false`                  |   `DISABLE_MINIFICATION`    |

 ### `build` command (aliases: `b`)

@ -448,14 +693,15 @@ $ error-pages [GLOBAL FLAGS] build [COMMAND FLAGS] [ARGUMENTS...]

 The following flags are supported:

-| Name                                        | Description                                                                                                                                                                                                                                                                                                               | Default value | Environment variables |
-|---------------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|:-------------:|:---------------------:|
-| `--add-template="…"`                        | To add a new template, provide the path to the file using this flag (the filename without the extension will be used as the template name)                                                                                                                                                                                |     `[]`      |        *none*         |
-| `--disable-template="…"`                    | Disable the specified template by its name (useful to disable the built-in templates and use only custom ones)                                                                                                                                                                                                            |     `[]`      |        *none*         |
-| `--add-code="…"`                            | To add a new HTTP status code, provide the code and its message/description using this flag (the format should be '%code%=%message%/%description%'; the code may contain a wildcard '*' to cover multiple codes at once, for example, '4**' will cover all 4xx codes unless a more specific code is described previously) |    `map[]`    |        *none*         |
-| `--disable-l10n`                            | Disable localization of error pages (if the template supports localization)                                                                                                                                                                                                                                               |    `false`    |    `DISABLE_L10N`     |
-| `--index` (`-i`)                            | Generate index.html file with links to all error pages                                                                                                                                                                                                                                                                    |    `false`    |        *none*         |
-| `--target-dir="…"` (`--out`, `--dir`, `-o`) | Directory to put the built error pages into                                                                                                                                                                                                                                                                               |      `.`      |        *none*         |
+| Name                                        | Description                                                                                                                                                                                                                                                                                                               | Default value |  Environment variables |
+|---------------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|:-------------:|:----------------------:|
+| `--add-template="…"`                        | To add a new template, provide the path to the file using this flag (the filename without the extension will be used as the template name)                                                                                                                                                                                |     `[]`      |     `ADD_TEMPLATE`     |
+| `--disable-template="…"`                    | Disable the specified template by its name (useful to disable the built-in templates and use only custom ones)                                                                                                                                                                                                            |     `[]`      |         *none*         |
+| `--add-code="…"`                            | To add a new HTTP status code, provide the code and its message/description using this flag (the format should be '%code%=%message%/%description%'; the code may contain a wildcard '*' to cover multiple codes at once, for example, '4**' will cover all 4xx codes unless a more specific code is described previously) |    `map[]`    |         *none*         |
+| `--disable-l10n`                            | Disable localization of error pages (if the template supports localization)                                                                                                                                                                                                                                               |    `false`    |     `DISABLE_L10N`     |
+| `--index` (`-i`)                            | Generate index.html file with links to all error pages                                                                                                                                                                                                                                                                    |    `false`    |         *none*         |
+| `--target-dir="…"` (`--out`, `--dir`, `-o`) | Directory to put the built error pages into                                                                                                                                                                                                                                                                               |      `.`      |         *none*         |
+| `--disable-minification`                    | Disable the minification of HTML pages, including CSS, SVG, and JS (may be useful for debugging)                                                                                                                                                                                                                          |    `false`    | `DISABLE_MINIFICATION` |

 ### `healthcheck` command (aliases: `chk`, `health`, `check`)

@ -475,149 +721,6 @@ The following flags are supported:

 <!--/GENERATED:CLI_DOCS-->

-## 🪂 Templates (themes)
-
-The following templates are built-in and available for use without any additional setup:
-
-> [!NOTE]
-> The `cats` template is the only one of those that fetches resources (the actual cat pictures) from external
-> servers - all other templates are self-contained.
-
-<table>
-  <thead>
-    <tr>
-      <th>Template</th>
-      <th>Preview</th>
-    </tr>
-  </thead>
-  <tbody>
-    <tr>
-      <td align="center">
-        <code>app-down</code><br/><br/>
-        <img src="https://img.shields.io/badge/dynamic/json?url=https%3A%2F%2Ferror-pages.goatcounter.com%2Fcounter%2F%2Fuse-template%2Fapp-down.json&query=%24.count&label=used%20times" alt="used times">
-      </td>
-      <td>
-        <picture>
-          <source media="(prefers-color-scheme: dark)" srcset="https://github.com/tarampampam/error-pages/assets/7326800/4e668a56-a4c4-47cd-ac4d-b6b45db54ab8">
-          <img align="center" src="https://github.com/tarampampam/error-pages/assets/7326800/ad4b4fd7-7c7b-4bdc-a6b6-44f9ba7f77ca">
-        </picture>
-      </td>
-    </tr>
-    <tr>
-      <td align="center">
-        <code>cats</code><br/><br/>
-        <img src="https://img.shields.io/badge/dynamic/json?url=https%3A%2F%2Ferror-pages.goatcounter.com%2Fcounter%2F%2Fuse-template%2Fcats.json&query=%24.count&label=used%20times" alt="used times">
-      </td>
-      <td>
-        <picture>
-          <source media="(prefers-color-scheme: dark)" srcset="https://github.com/tarampampam/error-pages/assets/7326800/5689880b-f770-406c-81dd-2d28629e6f2e">
-          <img align="center" src="https://github.com/tarampampam/error-pages/assets/7326800/056cd00e-bc9a-4120-8325-310d7b0ebd1b">
-        </picture>
-      </td>
-    </tr>
-    <tr>
-      <td align="center">
-        <code>connection</code><br/><br/>
-        <img src="https://img.shields.io/badge/dynamic/json?url=https%3A%2F%2Ferror-pages.goatcounter.com%2Fcounter%2F%2Fuse-template%2Fconnection.json&query=%24.count&label=used%20times" alt="used times">
-      </td>
-      <td>
-        <picture>
-          <source media="(prefers-color-scheme: dark)" srcset="https://github.com/tarampampam/error-pages/assets/7326800/3f03dc1b-c1ee-4a91-b3d7-e3b93c79020e">
-          <img align="center" src="https://github.com/tarampampam/error-pages/assets/7326800/099ecc2d-e724-4d9c-b5ed-66ddabd71139">
-        </picture>
-      </td>
-    </tr>
-    <tr>
-      <td align="center">
-        <code>ghost</code><br/><br/>
-        <img src="https://img.shields.io/badge/dynamic/json?url=https%3A%2F%2Ferror-pages.goatcounter.com%2Fcounter%2F%2Fuse-template%2Fghost.json&query=%24.count&label=used%20times" alt="used times">
-      </td>
-      <td>
-        <picture>
-          <source media="(prefers-color-scheme: dark)" srcset="https://github.com/tarampampam/error-pages/assets/7326800/714482ab-f8c1-4455-8ae8-b2ae78f7a2c6">
-          <img align="center" src="https://github.com/tarampampam/error-pages/assets/7326800/f253dfe7-96a0-4e96-915b-d4c544d4a237">
-        </picture>
-      </td>
-    </tr>
-    <tr>
-      <td align="center">
-        <code>hacker-terminal</code><br/><br/>
-        <img src="https://img.shields.io/badge/dynamic/json?url=https%3A%2F%2Ferror-pages.goatcounter.com%2Fcounter%2F%2Fuse-template%2Fhacker-terminal.json&query=%24.count&label=used%20times" alt="used times">
-      </td>
-      <td>
-        <picture>
-          <img align="center" src="https://github.com/tarampampam/error-pages/assets/7326800/c197fc35-0844-43d0-9830-82440cee4559">
-        </picture>
-      </td>
-    </tr>
-    <tr>
-      <td align="center">
-        <code>l7</code><br/><br/>
-        <img src="https://img.shields.io/badge/dynamic/json?url=https%3A%2F%2Ferror-pages.goatcounter.com%2Fcounter%2F%2Fuse-template%2Fl7.json&query=%24.count&label=used%20times" alt="used times">
-      </td>
-      <td>
-        <picture>
-          <source media="(prefers-color-scheme: dark)" srcset="https://github.com/tarampampam/error-pages/assets/7326800/18e43ea3-6389-4459-be41-0fc6566a073f">
-          <img align="center" src="https://github.com/tarampampam/error-pages/assets/7326800/05f26669-94ec-40ce-8d67-a199cde54202">
-        </picture>
-      </td>
-    </tr>
-    <tr>
-      <td align="center">
-        <code>lost-in-space</code><br/><br/>
-        <img src="https://img.shields.io/badge/dynamic/json?url=https%3A%2F%2Ferror-pages.goatcounter.com%2Fcounter%2F%2Fuse-template%2Flost-in-space.json&query=%24.count&label=used%20times" alt="used times">
-      </td>
-      <td>
-        <picture>
-          <source media="(prefers-color-scheme: dark)" srcset="https://github.com/tarampampam/error-pages/assets/7326800/debf87c0-6f27-41a8-b141-ee3464cbd6cc">
-          <img align="center" src="https://github.com/tarampampam/error-pages/assets/7326800/c347e63d-13a7-46d4-81b9-b25266819a1d">
-        </picture>
-      </td>
-    </tr>
-    <tr>
-      <td align="center">
-        <code>noise</code><br/><br/>
-        <img src="https://img.shields.io/badge/dynamic/json?url=https%3A%2F%2Ferror-pages.goatcounter.com%2Fcounter%2F%2Fuse-template%2Fnoise.json&query=%24.count&label=used%20times" alt="used times">
-      </td>
-      <td>
-        <picture>
-          <img align="center" src="https://github.com/tarampampam/error-pages/assets/7326800/4cc5c3bd-6ebb-4e96-bee8-02d4ad4e7266">
-        </picture>
-      </td>
-    </tr>
-    <tr>
-      <td align="center">
-        <code>orient</code><br/><br/>
-        <img src="https://img.shields.io/badge/dynamic/json?url=https%3A%2F%2Ferror-pages.goatcounter.com%2Fcounter%2F%2Fuse-template%2Forient.json&query=%24.count&label=used%20times" alt="used times">
-      </td>
-      <td>
-        <picture>
-          <source media="(prefers-color-scheme: dark)" srcset="https://github.com/tarampampam/error-pages/assets/7326800/bc2b0dad-c32c-4628-98f6-e3eab61dd1f2">
-          <img align="center" src="https://github.com/tarampampam/error-pages/assets/7326800/8fc0a7ea-694d-49ce-bb50-3ea032d52d1e">
-        </picture>
-      </td>
-    </tr>
-    <tr>
-      <td align="center">
-        <code>shuffle</code><br/><br/>
-        <img src="https://img.shields.io/badge/dynamic/json?url=https%3A%2F%2Ferror-pages.goatcounter.com%2Fcounter%2F%2Fuse-template%2Fshuffle.json&query=%24.count&label=used%20times" alt="used times">
-      </td>
-      <td>
-        <picture>
-          <source media="(prefers-color-scheme: dark)" srcset="https://github.com/tarampampam/error-pages/assets/7326800/7504b7c3-b0cb-4991-9ac2-759cd6c50fc0">
-          <img align="center" src="https://github.com/tarampampam/error-pages/assets/7326800/d2a73fc8-cf5f-4f42-bff8-cce33d8ae47e">
-        </picture>
-      </td>
-    </tr>
-  </tbody>
-</table>
-
-> [!NOTE]
-> The "used times" counter increments when someone start the server with the specified template. Stats service does
-> not collect any information about location, IP addresses, and so on. Moreover, the stats are open and available for
-> everyone at [error-pages.goatcounter.com](https://error-pages.goatcounter.com/). This is simply a counter to display
-> how often a particular template is used, nothing more.
-
 ## 🦾 Contributors

 I want to say a big thank you to everyone who contributed to this project:
--- a/go.mod
+++ b/go.mod
@ -4,6 +4,7 @@ go 1.22

 require (
 	github.com/stretchr/testify v1.9.0
+	github.com/tdewolff/minify/v2 v2.20.35
 	github.com/urfave/cli-docs/v3 v3.0.0-alpha5
 	github.com/urfave/cli/v3 v3.0.0-alpha9
 	github.com/valyala/fasthttp v1.55.0
@ -19,6 +20,7 @@ require (
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/rogpeppe/go-internal v1.12.0 // indirect
 	github.com/russross/blackfriday/v2 v2.1.0 // indirect
+	github.com/tdewolff/parse/v2 v2.7.15 // indirect
 	github.com/valyala/bytebufferpool v1.0.0 // indirect
 	github.com/xrash/smetrics v0.0.0-20240521201337-686a1a2994c1 // indirect
 	gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c // indirect
--- a/go.sum
+++ b/go.sum
@ -26,6 +26,13 @@ github.com/russross/blackfriday/v2 v2.1.0 h1:JIOH55/0cWyOuilr9/qlrm0BSXldqnqwMsf
 github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
 github.com/stretchr/testify v1.9.0 h1:HtqpIVDClZ4nwg75+f6Lvsy/wHu+3BoSGCbBAcpTsTg=
 github.com/stretchr/testify v1.9.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
+github.com/tdewolff/minify/v2 v2.20.35 h1:/Vq/oivpkFyi2PViD25XHZZbJz+eO4OmPSgePex1kBU=
+github.com/tdewolff/minify/v2 v2.20.35/go.mod h1:L1VYef/jwKw6Wwyk5A+T0mBjjn3mMPgmjjA688RNsxU=
+github.com/tdewolff/parse/v2 v2.7.15 h1:hysDXtdGZIRF5UZXwpfn3ZWRbm+ru4l53/ajBRGpCTw=
+github.com/tdewolff/parse/v2 v2.7.15/go.mod h1:3FbJWZp3XT9OWVN3Hmfp0p/a08v4h8J9W1aghka0soA=
+github.com/tdewolff/test v1.0.11-0.20231101010635-f1265d231d52/go.mod h1:6DAvZliBAAnD7rhVgwaM7DE5/d9NMOAJ09SqYqeK4QE=
+github.com/tdewolff/test v1.0.11-0.20240106005702-7de5f7df4739 h1:IkjBCtQOOjIn03u/dMQK9g+Iw9ewps4mCl1nB8Sscbo=
+github.com/tdewolff/test v1.0.11-0.20240106005702-7de5f7df4739/go.mod h1:XPuWBzvdUzhCuxWO1ojpXsyzsA5bFoS3tO/Q3kFuTG8=
 github.com/urfave/cli-docs/v3 v3.0.0-alpha5 h1:H1oWnR2/GN0dNm2PVylws+GxSOD6YOwW/jI5l78YfPk=
 github.com/urfave/cli-docs/v3 v3.0.0-alpha5/go.mod h1:AIqom6Q60U4tiqHp41i7+/AB2XHgi1WvQ7jOFlccmZ4=
 github.com/urfave/cli/v3 v3.0.0-alpha9 h1:P0RMy5fQm1AslQS+XCmy9UknDXctOmG/q/FZkUFnJSo=
--- a/internal/cli/app.go
+++ b/internal/cli/app.go
@ -6,7 +6,6 @@ import (
 	"runtime"
 	"strings"

-	_ "github.com/urfave/cli-docs/v3" // required for `go generate` to work
 	"github.com/urfave/cli/v3"

 	"gh.tarampamp.am/error-pages/internal/appmeta"
@ -17,7 +16,7 @@ import (
 	"gh.tarampamp.am/error-pages/internal/logger"
 )

-//go:generate go run update_readme.go
+//go:generate go run app_generate.go

 // NewApp creates a new console application.
 func NewApp(appName string) *cli.Command { //nolint:funlen
--- a/internal/cli/update_readme.go
+++ b/internal/cli/update_readme.go
@ -1,5 +1,4 @@
-//go:build ignore
-// +build ignore
+//go:build generate

 package main

@ -17,8 +16,10 @@ func main() {
 	if stat, err := os.Stat(readmePath); err == nil && stat.Mode().IsRegular() {
 		if err = cliDocs.ToTabularToFileBetweenTags(cli.NewApp(""), "error-pages", readmePath); err != nil {
 			panic(err)
+		} else {
+			println("✔ cli docs updated successfully")
 		}
 	} else if err != nil {
-		println("readme file not found, cli docs not updated:", err.Error())
+		println("⚠ readme file not found, cli docs not updated:", err.Error())
 	}
 }
--- a/internal/cli/build/command.go
+++ b/internal/cli/build/command.go
@ -39,11 +39,12 @@ func NewCommand(log *logger.Logger) *cli.Command { //nolint:funlen,gocognit
 		cmd command
 		cfg = config.New()

-		addTplFlag      = shared.AddTemplatesFlag
-		disableTplFlag  = shared.DisableTemplateNamesFlag
-		addCodeFlag     = shared.AddHTTPCodesFlag
-		disableL10nFlag = shared.DisableL10nFlag
-		createIndexFlag = cli.BoolFlag{
+		addTplFlag              = shared.AddTemplatesFlag
+		disableTplFlag          = shared.DisableTemplateNamesFlag
+		addCodeFlag             = shared.AddHTTPCodesFlag
+		disableL10nFlag         = shared.DisableL10nFlag
+		disableMinificationFlag = shared.DisableMinificationFlag
+		createIndexFlag         = cli.BoolFlag{
 			Name:     "index",
 			Aliases:  []string{"i"},
 			Usage:    "Generate index.html file with links to all error pages",
@ -81,6 +82,7 @@ func NewCommand(log *logger.Logger) *cli.Command { //nolint:funlen,gocognit
 		Usage:   "Build the static error pages and put them into a specified directory",
 		Action: func(ctx context.Context, c *cli.Command) error {
 			cfg.L10n.Disable = c.Bool(disableL10nFlag.Name)
+			cfg.DisableMinification = c.Bool(disableMinificationFlag.Name)
 			cmd.opt.createIndex = c.Bool(createIndexFlag.Name)
 			cmd.opt.targetDirAbsPath, _ = filepath.Abs(c.String(targetDirFlag.Name)) // an error checked by [os.Stat] validator

@ -140,13 +142,14 @@ func NewCommand(log *logger.Logger) *cli.Command { //nolint:funlen,gocognit
 			&disableL10nFlag,
 			&createIndexFlag,
 			&targetDirFlag,
+			&disableMinificationFlag,
 		},
 	}

 	return cmd.c
 }

-func (cmd *command) Run( //nolint:funlen
+func (cmd *command) Run( //nolint:funlen,gocognit
 	ctx context.Context,
 	log *logger.Logger,
 	cfg *config.Config,
@ -172,13 +175,21 @@ func (cmd *command) Run( //nolint:funlen

 			var outFilePath = path.Join(cmd.opt.targetDirAbsPath, templateName, code+".html")

-			if content, renderErr := appTemplate.Render(templateContent, appTemplate.Props{
+			if content, renderErr := appTemplate.Render(templateContent, appTemplate.Props{ //nolint:nestif
 				Code:               uint16(codeAsUint),
 				Message:            codeDescription.Message,
 				Description:        codeDescription.Description,
 				L10nDisabled:       cfg.L10n.Disable,
 				ShowRequestDetails: false,
 			}); renderErr == nil {
+				if !cfg.DisableMinification {
+					if mini, minErr := appTemplate.MiniHTML(content); minErr != nil {
+						log.Warn("Cannot minify the content", logger.Error(minErr))
+					} else {
+						content = mini
+					}
+				}
+
 				if err := os.WriteFile(outFilePath, []byte(content), os.FileMode(0664)); err != nil { //nolint:mnd
 					return err
 				}
--- a/internal/cli/serve/command.go
+++ b/internal/cli/serve/command.go
@ -38,13 +38,14 @@ func NewCommand(log *logger.Logger) *cli.Command { //nolint:funlen,gocognit,gocy
 	)

 	var (
-		addrFlag        = shared.ListenAddrFlag
-		portFlag        = shared.ListenPortFlag
-		addTplFlag      = shared.AddTemplatesFlag
-		disableTplFlag  = shared.DisableTemplateNamesFlag
-		addCodeFlag     = shared.AddHTTPCodesFlag
-		disableL10nFlag = shared.DisableL10nFlag
-		jsonFormatFlag  = cli.StringFlag{
+		addrFlag                = shared.ListenAddrFlag
+		portFlag                = shared.ListenPortFlag
+		addTplFlag              = shared.AddTemplatesFlag
+		disableTplFlag          = shared.DisableTemplateNamesFlag
+		addCodeFlag             = shared.AddHTTPCodesFlag
+		disableL10nFlag         = shared.DisableL10nFlag
+		disableMinificationFlag = shared.DisableMinificationFlag
+		jsonFormatFlag          = cli.StringFlag{
 			Name: "json-format",
 			Usage: "Override the default error page response in JSON format (Go templates are supported; the error " +
 				"page will use this template if the client requests JSON content type)",
@ -182,6 +183,7 @@ func NewCommand(log *logger.Logger) *cli.Command { //nolint:funlen,gocognit,gocy
 			cfg.RespondWithSameHTTPCode = c.Bool(sendSameHTTPCodeFlag.Name)
 			cfg.RotationMode, _ = config.ParseRotationMode(c.String(rotationModeFlag.Name))
 			cfg.ShowDetails = c.Bool(showDetailsFlag.Name)
+			cfg.DisableMinification = c.Bool(disableMinificationFlag.Name)

 			{ // override default JSON, XML, and PlainText formats
 				if c.IsSet(jsonFormatFlag.Name) {
@ -303,6 +305,7 @@ func NewCommand(log *logger.Logger) *cli.Command { //nolint:funlen,gocognit,gocy
 			&proxyHeadersListFlag,
 			&rotationModeFlag,
 			&readBufferSizeFlag,
+			&disableMinificationFlag,
 		},
 	}

--- a/internal/cli/shared/flags.go
+++ b/internal/cli/shared/flags.go
@ -67,6 +67,7 @@ var AddTemplatesFlag = cli.StringSliceFlag{
 	Usage: "To add a new template, provide the path to the file using this flag (the filename without the extension " +
 		"will be used as the template name)",
 	Config:   cli.StringConfig{TrimSpace: true},
+	Sources:  cli.EnvVars("ADD_TEMPLATE"),
 	Category: CategoryTemplates,
 	Validator: func(paths []string) error {
 		for _, path := range paths {
@ -146,3 +147,11 @@ var DisableL10nFlag = cli.BoolFlag{
 	Category: CategoryOther,
 	OnlyOnce: true,
 }
+
+var DisableMinificationFlag = cli.BoolFlag{
+	Name:     "disable-minification",
+	Usage:    "Disable the minification of HTML pages, including CSS, SVG, and JS (may be useful for debugging)",
+	Sources:  cli.EnvVars("DISABLE_MINIFICATION"),
+	Category: CategoryOther,
+	OnlyOnce: true,
+}
--- a/internal/cli/shared/flags_test.go
+++ b/internal/cli/shared/flags_test.go
@ -91,6 +91,7 @@ func TestAddTemplatesFlag(t *testing.T) {
 	var flag = shared.AddTemplatesFlag

 	assert.Equal(t, "add-template", flag.Name)
+	assert.Contains(t, flag.Sources.String(), "ADD_TEMPLATE")

 	for wantErrMsg, giveValue := range map[string][]string{
 		"missing template path":     {""},
@ -216,3 +217,12 @@ func TestDisableL10nFlag(t *testing.T) {
 	assert.Equal(t, "disable-l10n", flag.Name)
 	assert.Contains(t, flag.Sources.String(), "DISABLE_L10N")
 }
+
+func TestDisableMinificationFlag(t *testing.T) {
+	t.Parallel()
+
+	var flag = shared.DisableMinificationFlag
+
+	assert.Equal(t, "disable-minification", flag.Name)
+	assert.Contains(t, flag.Sources.String(), "DISABLE_MINIFICATION")
+}
--- a/internal/config/config.go
+++ b/internal/config/config.go
@ -56,6 +56,9 @@ type Config struct {
 	// ShowDetails determines whether to show additional details in the error response, extracted from the
 	// incoming request (if supported by the template).
 	ShowDetails bool
+
+	// DisableMinification determines whether to disable minification of the rendered content (e.g., HTML, CSS) or not.
+	DisableMinification bool
 }

 const defaultJSONFormat string = `{
--- a/internal/config/config_test.go
+++ b/internal/config/config_test.go
@ -24,6 +24,7 @@ func TestNew(t *testing.T) {
 		assert.NotEmpty(t, cfg.TemplateName)
 		assert.True(t, cfg.Templates.Has(cfg.TemplateName))
 		assert.Equal(t, uint16(http.StatusNotFound), cfg.DefaultCodeToRender)
+		assert.False(t, cfg.DisableMinification)
 	})

 	t.Run("changing cfg1 should not affect cfg2", func(t *testing.T) {
--- a/internal/http/handlers/error_page/handler.go
+++ b/internal/http/handlers/error_page/handler.go
@ -175,6 +175,14 @@ func New(cfg *config.Config, log *logger.Logger) (_ fasthttp.RequestHandler, clo
 							err.Error(),
 						))
 					} else {
+						if !cfg.DisableMinification {
+							if mini, minErr := template.MiniHTML(content); minErr != nil {
+								log.Warn("HTML minification failed", logger.Error(minErr))
+							} else {
+								content = mini
+							}
+						}
+
 						cache.Put(tpl, tplProps, []byte(content))

 						write(ctx, log, content)
--- a/internal/http/handlers/error_page/handler_test.go
+++ b/internal/http/handlers/error_page/handler_test.go
@ -48,7 +48,7 @@ func TestHandler(t *testing.T) {
 			wantStatusCode: http.StatusOK,
 			wantHeaders:    map[string]string{"Content-Type": "text/html; charset=utf-8"},
 			wantBodyIncludes: []string{
-				"<!DOCTYPE html>",
+				"<!doctype html>",
 				"<title>407: Proxy Authentication Required",
 				"Proxy Authentication Required",
 			},
--- a/internal/template/minify.go
+++ b/internal/template/minify.go
@ -0,0 +1,23 @@
+package template
+
+import (
+	"github.com/tdewolff/minify/v2"
+	"github.com/tdewolff/minify/v2/css"
+	"github.com/tdewolff/minify/v2/html"
+	"github.com/tdewolff/minify/v2/js"
+	"github.com/tdewolff/minify/v2/svg"
+)
+
+var htmlMinify = func() *minify.M { //nolint:gochecknoglobals
+	var m = minify.New()
+
+	m.AddFunc("text/css", css.Minify)
+	m.Add("text/html", &html.Minifier{KeepDocumentTags: true, KeepEndTags: true, KeepQuotes: true})
+	m.AddFunc("image/svg+xml", svg.Minify)
+	m.AddFunc("application/javascript", js.Minify)
+
+	return m
+}()
+
+// MiniHTML minifies HTML data, including inline CSS, SVG and JS.
+func MiniHTML(data string) (string, error) { return htmlMinify.String("text/html", data) }
--- a/internal/template/minify_test.go
+++ b/internal/template/minify_test.go
@ -0,0 +1,94 @@
+package template_test
+
+import (
+	"sync"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"gh.tarampamp.am/error-pages/internal/template"
+)
+
+func TestMiniHTML(t *testing.T) {
+	t.Parallel()
+
+	var wg sync.WaitGroup
+
+	for range 100 { // race condition provocation
+		wg.Add(1)
+
+		go func() {
+			defer wg.Done()
+
+			for give, want := range map[string]string{
+				"": "",
+				`<!-- Simple HTML page -->
+<!DOCTYPE html>
+<html>
+<head>
+	<title>Test</title>
+</head>
+<body>
+	<h1 align="center">Test</h1>
+</body>
+</html>`: `<!doctype html><html><head><title>Test</title></head><body><h1 align="center">Test</h1></body></html>`,
+				`<!-- css styles -->
+<html>
+<head>
+	<style>
+		.foo:hover {
+			color: #f0a; /* comment */
+		}
+	</style>
+</head>
+<body>
+	<p style="color: red" class="bar">Text</p>
+</body>
+</html>`: `<html><head><style>.foo:hover{color:#f0a}</style></head><body><p style="color:red" class="bar">Text</p></body></html>`,
+				`<!-- svg -->
+<svg xmlns="http://www.w3.org/2000/svg">
+	<g>
+		<circle cx="50" cy="50" r="40" stroke="black" stroke-width="3" fill="red" />
+	</g>
+</svg>`: `<svg><g><circle cx="50" cy="50" r="40" stroke="#000" stroke-width="3" fill="red"/></g></svg>`,
+				`<!-- js -->
+<html>
+<body>
+<script>
+	// comment
+	console.log('Hello, World!');
+
+	let foo = 1;
+	foo++;
+</script>
+</body>
+</html>`: `<html><body><script>console.log("Hello, World!");let foo=1;foo++</script></body></html>`,
+				`<!-- js module not changed -->
+<html>
+<body>
+<script type="module">
+	// comment
+	console.log('Hello, World!');
+
+	let foo = 1;
+	foo++;
+</script>
+</body>
+</html>`: `<html><body><script type="module">
+	// comment
+	console.log('Hello, World!');
+
+	let foo = 1;
+	foo++;
+</script></body></html>`,
+			} {
+				var got, err = template.MiniHTML(give)
+
+				assert.NoError(t, err)
+				assert.Equal(t, want, got)
+			}
+		}()
+	}
+
+	wg.Wait()
+}
Author	SHA1	Message	Date
Pаramtamtām	c15991458c	Add env variable ADD_TEMPLATE (#295 )	2024-07-06 14:01:17 +04:00
Paramtamtam	7a2d3c1337	Update readme file and CI	2024-07-05 19:03:08 +04:00
Pаramtamtām	141c18cf29	feat: Add HTML/CSS/JS minification on the fly (#293 )	2024-07-05 18:59:07 +04:00
Pаramtamtām	b677064733	fix: Forgot to include the SSL certificates in the Docker image (#292 )	2024-07-05 14:01:06 +04:00
Paramtamtam	3782a875e2	ci: 👷 CI system updated	2024-07-05 13:10:41 +04:00
Paramtamtam	1241579222	ci: 👷 CI system updated	2024-07-05 12:56:55 +04:00
Paramtamtam	ac865804dd	docs(readme): 📚 Readme file updated	2024-07-05 12:42:13 +04:00
Paramtamtam	cf475cb98b	docs(readme): 📚 Readme file updated	2024-07-05 12:35:34 +04:00
Paramtamtam	086aa29fda	docs(readme): 📚 Readme file updated	2024-07-05 12:30:45 +04:00
Paramtamtam	6d40c7797a	dockerfile update	2024-07-04 12:17:34 +04:00
Pаramtamtām	052409f945	One more readme file update	2024-07-03 20:41:35 +00:00
Pаramtamtām	5462a1f664	Readme file update	2024-07-03 20:37:34 +00:00
Paramtamtam	b4e9ea5ea6	docs(readme): 📚 Readme file updated	2024-07-03 19:08:50 +04:00
Paramtamtam	a19cc5cb76	docs(readme): 📚 Readme file updated	2024-07-03 19:07:17 +04:00