Optimized docker build caching (sort of)

.gitignore

@@ -21,6 +21,7 @@ ui/config/apiconfig.js
 
 # Include sample config files
 !api/config/*.sample.js
+!api/config/cacheControl.js
 
 # Whitelist anchor files & .gitignore
 !.gitignore

api/app.js

@@ -1,16 +1,30 @@
+// Cache control settings
+const cacheControl = require("./config/cacheControl");
+
 // app package loading
 let app = require("./src/app-setup");
 
 // Setup the routes
 app.get("/api/v1/mail/list",   require("./src/api/mailList"));
-app.get("/api/v1/mail/getKey", require("./src/api/mailGetKey"));
+app.get("/api/v1/mail/getInfo", require("./src/api/mailGetInfo"));
 app.get("/api/v1/mail/getHtml", require("./src/api/mailGetHtml"));
 
-// Static folder hosting
-app.use( app.express.static("public") )
+// Legacy fallback behaviour - 
+// Note this is to be deprecated (after updating UI)
+app.get("/api/v1/mail/getKey", require("./src/api/mailGetInfo"));
+
+// Static folder hosting with cache control
+// See express static options: https://expressjs.com/en/4x/api.html#express.static
+app.use( app.express.static("public", {
+	etag: true,
+	setHeaders: function (res, path, stat) {
+		res.set('cache-control', cacheControl.static)
+	}
+}) )
 
 // Custom 404 handling - use index.html
 app.use(function(req, res) {
+	res.set('cache-control', cacheControl.static)
 	res.sendFile(__dirname + '/public/index.html');
 });
 

api/config/cacheControl.js

@@ -0,0 +1,11 @@
+/**
+ * Configure the various level of cache controls
+ */
+module.exports = {
+    // Frequent changing dynamic content
+    "dynamic": "public, max-age=1, max-stale=1, stale-while-revalidate=10, stale-if-error=86400",
+
+    // Rarely changing static content
+    // with very aggressive caching
+    "static": "public, max-age=10, max-stale=10, stale-while-revalidate=3600, stale-if-error=86400"
+}

api/src/api/mailGetHtml.js

@@ -1,11 +1,12 @@
 // Loading mailgun reader and config
 const mailgunReader = require("../mailgunReader");
 const mailgunConfig = require("../../config/mailgunConfig");
+const cacheControl  = require("../../config/cacheControl");
 
 const reader = new mailgunReader(mailgunConfig);
 
 /**
- * Get and return the URL content from the mailgun API
+ * Get and return the etatic email HTML content from the mailgun API, given the mailKey
  *
  * @param {*} req
  * @param {*} res
@@ -31,9 +32,10 @@ module.exports = function(req, res){
 			// eslint-disable-next-line
 			'<\/script>'
 
-	res.status(200).send(body)
+		res.set('cache-control', cacheControl.static)
+		res.status(200).send(body)
 	})
 	.catch(e => {
-			res.status(500).send("{error: '"+e+"'}")
+		res.status(500).send("{error: '"+e+"'}")
 	});
 }

api/src/api/mailGetKey.js → api/src/api/mailGetInfo.js

@@ -1,11 +1,12 @@
 // Loading mailgun reader and config
 const mailgunReader = require("../mailgunReader");
 const mailgunConfig = require("../../config/mailgunConfig");
+const cacheControl  = require("../../config/cacheControl");
 
 const reader = new mailgunReader(mailgunConfig);
 
 /**
- * Get and return the URL content from the mailgun API
+ * Get and return the static email header details from the mailgun API given the mailKey
  *
  * @param {*} req
  * @param {*} res
@@ -18,22 +19,25 @@ module.exports = function(req, res){
 	}
 
 	reader.getKey(mailKey).then(response => {
-			let emailDetails = {}
+		let emailDetails = {}
 
-			// Format and extract the name of the user
-			let [name, ...rest] = formatName(response.from)
-			emailDetails.name = name
+		// Format and extract the name of the user
+		let [name, ...rest] = formatName(response.from)
+		emailDetails.name = name
 
-			// Extract the rest of the email domain after splitting
-			if (rest[0].length > 0) {
-				emailDetails.emailAddress = ' <' + rest
-			}
+		// Extract the rest of the email domain after splitting
+		if (rest[0].length > 0) {
+			emailDetails.emailAddress = ' <' + rest
+		}
 
-			// Extract the subject of the response
-			emailDetails.subject = response.subject
+		// Extract the subject of the response
+		emailDetails.subject = response.subject
 
-			// Extract the recipients
-			emailDetails.recipients = response.recipients
+		// Extract the recipients
+		emailDetails.recipients = response.recipients
+
+		// Return with cache control
+		res.set('cache-control', cacheControl.static)
 		res.status(200).send(emailDetails)
 	})
 	.catch(e => {

api/src/api/mailGetUrl.js

@@ -1,11 +1,14 @@
 // Loading mailgun reader and config
 const mailgunReader = require("../mailgunReader");
 const mailgunConfig = require("../../config/mailgunConfig");
+const cacheControl  = require("../../config/cacheControl");
 
 const reader = new mailgunReader(mailgunConfig);
 
 /**
- * Get and return the URL content from the mailgun API
+ * Get and return the URL link from the mailgun API - for the mail gcontent
+ * 
+ * NOTE - this is to be deprecated
  *
  * @param {*} req
  * @param {*} res
@@ -18,7 +21,8 @@ module.exports = function(req, res){
 	}
 
 	reader.getUrl(url).then(response => {
-		 res.status(200).send(response)
+		res.set('cache-control', cacheControl.static)
+		res.status(200).send(response)
 	})
 	.catch(e => {
 		res.status(500).send("{error: '"+e+"'}")

api/src/api/mailList.js

@@ -1,11 +1,12 @@
 // Loading mailgun reader and config
 const mailgunReader = require("../mailgunReader");
 const mailgunConfig = require("../../config/mailgunConfig");
+const cacheControl  = require("../../config/cacheControl");
 
 const reader = new mailgunReader(mailgunConfig);
 
 /**
- * Mail listing api, returns the item list
+ * Mail listing api, returns the list of emails
  *
  * @param {*} req
  * @param {*} res
@@ -24,7 +25,8 @@ module.exports = function(req, res){
 	}
 
 	reader.recipientEventList(recipient+"@"+mailgunConfig.emailDomain).then(response => {
-		 res.status(200).send(response.items)
+		res.set('cache-control', cacheControl.dynamic)
+		res.status(200).send(response.items)
 	})
 	.catch(e => {
 		res.status(500).send("{error: '"+e+"'}")

docker-entrypoint.sh

@@ -1,5 +1,12 @@
 #!/bin/sh
 
+#
+# Entrypoint start
+#
+echo ">>---------------------------------------------------------------------"
+echo ">> Starting inboxkitten container : Get Mail Nyow!"
+echo ">>---------------------------------------------------------------------"
+
 #
 # Getting the various configuration settings from command line / environment variable
 #
@@ -11,9 +18,8 @@ else
 fi
 
 if [ -z "$MAILGUN_API_KEY" ]; then
-	echo ">> Please type in your MAILGUN_API_KEY";
-	read -sp '>> MAILGUN_API_KEY : ' MAILGUN_API_KEY;
-	echo "";
+	echo "[FATAL ERROR] Missing MAILGUN_API_KEY";
+	exit 1;
 else
 	echo ">> Detected MAILGUN_API_KEY env variable : [intentionally redacted]";
 fi
@@ -25,25 +31,47 @@ else
 	echo ">> Detected WEBSITE_DOMAIN env variable : $WEBSITE_DOMAIN";
 fi
 
+#
+# End of env variable checks
+# Moving to config setups
+#
+echo ">>---------------------------------------------------------------------"
+
+# Debug check
+# ls /application/
+
 #
 # Setup the UI
 #
 echo ">> Setting up UI"
 
 # Clone the files
-rm -rf /application/api/public/*
-cp -r /application/ui-dist/ /application/api/public/
+rm -rf /application/api/public/
+mkdir /application/api/public/
+cp -r /application/ui-dist/* /application/api/public/
+
+# Debug check
+# ls /application/api/public/
+
+# Search token (so that it does not get character substituted)
+TOKEN_MAILGUN_EMAIL_DOMAIN='${MAILGUN_EMAIL_DOMAIN}'
+TOKEN_WEBSITE_DOMAIN='${WEBSITE_DOMAIN}'
 
 # Find and replace
-find /application/api/public/ -type f -exec sed -i "s/\$\{MAILGUN_EMAIL_DOMAIN\}/$MAILGUN_EMAIL_DOMAIN/g" {} +
-find /application/api/public/ -type f -exec sed -i "s/\$\{WEBSITE_DOMAIN\}/$WEBSITE_DOMAIN/g" {} +
+find /application/api/public/ -type f -exec sed -i "s/$TOKEN_MAILGUN_EMAIL_DOMAIN/$MAILGUN_EMAIL_DOMAIN/g" {} +
+find /application/api/public/ -type f -exec sed -i "s/$TOKEN_WEBSITE_DOMAIN/$WEBSITE_DOMAIN/g" {} +
 
 #
 # Setup the API
 #
 echo ">> Setting up API config"
-cat "application/api/config/mailgunConfig.sample.js" | envsubst > "application/api/config/mailgunConfig.js"
+cat "/application/api/config/mailgunConfig.sample.js" | envsubst > "/application/api/config/mailgunConfig.js"
 
-# Start the API
+#
+# Start the server
+#
+echo ">>---------------------------------------------------------------------"
+echo ">> Starting the server"
+echo ">>---------------------------------------------------------------------"
 cd /application/api/
 npm start

dockerfile

@@ -1,61 +1,79 @@
+#-------------------------------------------------------
 #
+# Base alpine images with all the runtime os dependencies
 #
-# Base alpine image with all the various dependencies
-#
-# Note that the node sass is broken with
+# Note that the node-sass is broken with node 12
 # https://github.com/nodejs/docker-node/issues/1028
 #
-#
-FROM node:10-alpine AS baseimage
+#-------------------------------------------------------
 
-# Install dependencies
+# Does basic node, and runtime dependencies
+FROM node:10-alpine AS baseimage
 RUN apk add --no-cache gettext
-
-# Setup the /application/ directory
 RUN mkdir -p /application/
 # WORKDIR /application/
 
+#-------------------------------------------------------
 #
+# code builders (used by dockerbuilders)
 #
-# Initial docker builder (resets node_modules)
-#
-#
-FROM baseimage AS builder
+#-------------------------------------------------------
 
-# node-gyp installation 
+# Install dependencies for some NPM modules
+FROM baseimage AS codebuilder
 RUN apk add --no-cache make gcc g++ python
 
-# Copy over the requried files
-COPY api /application/api/
-COPY ui  /application/ui/
-COPY docker-entrypoint.sh  /application/docker-entrypoint.sh
+#-------------------------------------------------------
+#
+# Docker builders (also resets node_modules)
+#
+# Note each major dependency is compiled seperately
+# so as to isolate the impact of each code change
+#
+#-------------------------------------------------------
 
-# Scrub out node_modules and built files
+# Build the API
+# with reseted node_modules
+FROM codebuilder AS apibuilder
+# copy and reset the code
+COPY api /application/api/
 RUN rm -rf /application/api/node_modules
+RUN cd /application/api && ls && npm install
+
+# Build the UI
+# with reseted node_modules
+FROM codebuilder AS uibuilder
+# copy and reset the code
+COPY ui  /application/ui/
 RUN rm -rf /application/ui/node_modules
 RUN rm -rf /application/ui/dist
-
-# Lets do the initial npm install
 RUN cd /application/ui  && ls && npm install
-RUN cd /application/api && ls && npm install
-
 # Lets do the UI build
 RUN cp /application/ui/config/apiconfig.sample.js /application/ui/config/apiconfig.js
 RUN cd /application/ui && npm run build
 
+# Entry script 
+# & Permission reset
+FROM codebuilder AS entrypointbuilder
+COPY docker-entrypoint.sh  /application/docker-entrypoint.sh
+RUN chmod +x /application/docker-entrypoint.sh
+
+#-------------------------------------------------------
 #
+# Full Docker application
 #
-# Docker application
-#
-#
-FROM node:12-alpine as application
+#-------------------------------------------------------
+FROM baseimage as inboxkitten
 
 # Copy over the built files
-COPY --from=builder /application/api     /application/
-COPY --from=builder /application/ui/dist /application/ui-dist
+COPY --from=apibuilder        /application/api                  /application/api
+COPY --from=uibuilder         /application/ui/dist              /application/ui-dist
+COPY --from=entrypointbuilder /application/docker-entrypoint.sh /application/docker-entrypoint.sh
 
 # Debugging logging
-RUN ls /application
+# RUN ls /application/./
+# RUN ls /application/ui-dist
+# RUN ls /application/api
 
 # Expose the server port
 EXPOSE 8000
@@ -73,6 +91,9 @@ ENV WEBSITE_DOMAIN=""
 # RUN cd /application/ui  && ls && npm install
 # RUN cd /application/api && ls && npm install
 
+# Setup the workdir
+WORKDIR "/application/"
+
 # Setup the entrypoint
 ENTRYPOINT [ "/application/docker-entrypoint.sh" ]
 CMD []