[deploy] Add Imgproxy docs (#11104)

Co-authored-by: Molly Struve <mollylbs@gmail.com>
Co-authored-by: Vaidehi Joshi <vaidehi.sj@gmail.com>

docs/installation/imgproxy.md

@@ -0,0 +1,74 @@
+---
+title: Imgproxy
+---
+
+# Imgproxy
+
+Imgproxy is a standalone server for resizing images. It is optional and you do
+not need it to start Forem locally. We are currently only using it in Forem Cloud.
+
+## Installation
+
+- MacOS: install via homebrew with `brew install imgproxy`.
+- Window: please install
+  [via docker](https://docs.imgproxy.net/#/installation?id=docker).
+- Linux: you can either use
+  [docker installation](https://docs.imgproxy.net/#/installation?id=docker) or
+  [build from source](https://docs.imgproxy.net/#/installation?id=from-the-source).
+
+For more options not covered here, please take a look at the
+[official installation documentation](https://docs.imgproxy.net/#/installation).
+
+## Usage
+
+1. Generate a key/salt pair by running the following in your terminal twice.
+   Copy those values to your `.env` in the next step
+
+   ```
+   echo $(xxd -g 2 -l 64 -p /dev/random | tr -d '\n')
+   ```
+
+1. In your `.env`, add the following.
+
+   ```
+   export IMGPROXY_ENDPOINT='http://localhost:8080'
+   export IMGPROXY_KEY='1b1c9aae804e070b0864f2547fba7ce8ff31bf7..........'
+   export IMGPROXY_SALT='8c6d449d4fc2cada5bab538826cae709d2ade9f.........'
+   ```
+
+1. Start the Forem app server normally.
+
+1. Start Imgproxy in a terminal with the key and salt.
+
+   ```
+   # If you installed via homebrew or using the binary.
+   > IMGPROXY_KEY='your key' IMGPROXY_SALT='your salt' imgproxy
+
+   # If you are using Docker or Podman. The commands are identical for both
+   > docker run -p 8080:8080 \
+      -e IMGPROXY_KEY="your key" \
+      -e IMGPROXY_SALT="your salt" \
+      -it darthsim/imgproxy
+   ```
+
+1. That's it :)
+
+You should verify it's working by starting the Forem app locally and see that
+each image is loaded properly, or run the following command while the Forem app
+is running:
+
+```
+> curl -I http://localhost:8080/unsafe/aHR0cDovL2xvY2Fs/aG9zdDozMDAwL2Fz/c2V0cy8xLnBuZw
+
+HTTP/1.1 200 OK
+Server: imgproxy
+X-Request-Id: GYvCGXb98JUwL3ujwpjzh
+Date: Tue, 27 Oct 2020 16:11:37 GMT
+```
+
+## Sidenote
+
+- Because Imgproxy is a standalone server of its own, all image URLs given to it
+  need to be absolute URLs.
+- When working with Docker or Podman on Linux, provide the host network option
+  (`--network="host"`) so Imgproxy can properly access the localhost.

docs/installation/readme.md

@@ -6,6 +6,7 @@ items:
   - containers.md
   - gitpod.md
   - postgresql.md
+  - imgproxy.md
   - vault.md
   - others.md
 ---

docs/technical-overview/stack.md

@@ -11,7 +11,9 @@ For the Forem tech stack we use:
 - [_Redis_](https://redis.io/) to store cached data
 - [_Fastly_](https://www.fastly.com/) for
   [edge caching](https://dev.to/ben/making-devto-insanely-fast)
-- [_Cloudinary_](https://cloudinary.com/) for image manipulation/serving
+- [_Cloudinary_](https://cloudinary.com/) and/or
+  [_Imgproxy_](https://github.com/imgproxy/imgproxy) for image
+  manipulation/serving
 - [_Honeybadger_](https://www.honeybadger.io/) for error monitoring
 - [_Timber_](https://timber.io/) for logging
 - [_Sidekiq_](https://github.com/mperham/sidekiq) and

spec/services/images/optimizer_spec.rb

@@ -5,15 +5,6 @@ RSpec.describe Images::Optimizer, type: :service do
 
   let(:image_url) { "https://i.imgur.com/fKYKgo4.png" }
 
-  def stub_imgproxy
-    imgproxy_config_stub = Imgproxy::Config.new.tap do |config|
-      config.key = "secret"
-      config.salt = "secret"
-      config.base64_encode_urls = true
-    end
-    allow(Imgproxy).to receive(:config).and_return(imgproxy_config_stub)
-  end
-
   describe "#call" do
     before do
       allow(described_class).to receive(:cloudinary)
@@ -31,15 +22,9 @@ RSpec.describe Images::Optimizer, type: :service do
       expect(described_class).to have_received(:cloudinary)
     end
 
-    it "calls cloudinary if imgproxy's key and salt is missing" do
-      allow(Imgproxy).to receive(:config).and_return(Imgproxy::Config.new)
-      described_class.call(image_url, service: :imgproxy)
-      expect(described_class).to have_received(:cloudinary)
-    end
-
-    it "calls imgproxy if imgproxy's key and salt is provided" do
-      stub_imgproxy
-      described_class.call(image_url, service: :imgproxy)
+    it "calls imgproxy if imgproxy is enabled" do
+      allow(described_class).to receive(:imgproxy_enabled?).and_return(true)
+      described_class.call(image_url)
       expect(described_class).to have_received(:imgproxy)
     end
   end
@@ -72,12 +57,30 @@ RSpec.describe Images::Optimizer, type: :service do
 
   describe "#imgproxy" do
     it "works" do
-      stub_imgproxy
+      allow(described_class).to receive(:imgproxy_enabled?).and_return(true)
       imgproxy_url = described_class.imgproxy(image_url, service: :imgproxy, width: 500, height: 500)
       expect(imgproxy_url).to match(%r{/s:500:500/aHR0cHM6Ly9pLmlt/Z3VyLmNvbS9mS1lL/Z280LnBuZw})
     end
   end
 
+  describe "#imgproxy_enabled?" do
+    it "returns false if key and salt are missing" do
+      allow(Imgproxy).to receive(:config).and_return(Imgproxy::Config.new)
+      expect(described_class.imgproxy_enabled?).to eq(false)
+    end
+
+    it "returns true if key and salt are provided" do
+      imgproxy_config_stub = Imgproxy::Config.new.tap do |config|
+        config.key = "secret"
+        config.salt = "secret"
+        config.base64_encode_urls = true
+      end
+      allow(Imgproxy).to receive(:config).and_return(imgproxy_config_stub)
+
+      expect(described_class.imgproxy_enabled?).to eq(true)
+    end
+  end
+
   describe "#translate_cloudinary_options" do
     it "Set resizing_type to fill if crop: fill is provided" do
       options = { width: 100, height: 100, crop: "fill" }

spec/views/dashboards/show.html.erb_spec.rb

@@ -6,16 +6,10 @@ RSpec.describe "dashboards/show.html.erb", type: :view do
     stub_template "dashboards/_analytics.html.erb" => "stubbed content"
     stub_template "dashboards/_actions.html.erb" => "stubbed content"
 
-    Imgproxy.config.key = "secret"
-    Imgproxy.config.salt = "secret"
+    allow(Images::Optimizer).to receive(:imgproxy_enabled?).and_return(true)
     allow(SiteConfig).to receive(:mascot_image_url).and_return("https://i.imgur.com/fKYKgo4.png")
   end
 
-  after do
-    Imgproxy.config.key = nil
-    Imgproxy.config.endpoint = nil
-  end
-
   context "when using Imgproxy" do
     it "renders mascot image properly" do
       assign(:user, create(:user))