Update Jekyll, comment-out embed-code commands

Gemfile.lock

@@ -23,8 +23,8 @@ GEM
     commonmarker (0.17.13)
       ruby-enum (~> 0.5)
     concurrent-ruby (1.1.6)
-    dnsruby (1.61.3)
-      addressable (~> 2.5)
+    dnsruby (1.61.4)
+      simpleidn (~> 0.1)
     em-websocket (0.5.1)
       eventmachine (>= 0.12.9)
       http_parser.rb (~> 0.6.0)
@@ -37,9 +37,9 @@ GEM
     ffi (1.13.1)
     forwardable-extended (2.6.0)
     gemoji (3.0.1)
-    github-pages (206)
+    github-pages (207)
       github-pages-health-check (= 1.16.1)
-      jekyll (= 3.8.7)
+      jekyll (= 3.9.0)
       jekyll-avatar (= 0.7.0)
       jekyll-coffeescript (= 1.1.1)
       jekyll-commonmark-ghpages (= 0.1.6)
@@ -73,7 +73,8 @@ GEM
       jekyll-theme-time-machine (= 0.1.1)
       jekyll-titles-from-headings (= 0.5.3)
       jemoji (= 0.11.1)
-      kramdown (= 1.17.0)
+      kramdown (= 2.3.0)
+      kramdown-parser-gfm (= 1.1.0)
       liquid (= 4.0.3)
       mercenary (~> 0.3)
       minima (= 2.5.1)
@@ -100,14 +101,14 @@ GEM
     http_parser.rb (0.6.0)
     i18n (0.9.5)
       concurrent-ruby (~> 1.0)
-    jekyll (3.8.7)
+    jekyll (3.9.0)
       addressable (~> 2.4)
       colorator (~> 1.0)
       em-websocket (~> 0.5)
       i18n (~> 0.7)
       jekyll-sass-converter (~> 1.0)
       jekyll-watch (~> 2.0)
-      kramdown (~> 1.14)
+      kramdown (>= 1.17, < 3)
       liquid (~> 4.0)
       mercenary (~> 0.3.3)
       pathutil (~> 0.9)
@@ -206,7 +207,10 @@ GEM
       gemoji (~> 3.0)
       html-pipeline (~> 2.2)
       jekyll (>= 3.0, < 5.0)
-    kramdown (1.17.0)
+    kramdown (2.3.0)
+      rexml
+    kramdown-parser-gfm (1.1.0)
+      kramdown (~> 2.0)
     liquid (4.0.3)
     listen (3.2.1)
       rb-fsevent (~> 0.10, >= 0.10.3)
@@ -234,6 +238,7 @@ GEM
     rb-fsevent (0.10.4)
     rb-inotify (0.10.1)
       ffi (~> 1.0)
+    rexml (3.2.4)
     rouge (3.19.0)
     ruby-enum (0.8.0)
       i18n
@@ -247,13 +252,18 @@ GEM
     sawyer (0.8.2)
       addressable (>= 2.3.5)
       faraday (> 0.8, < 2.0)
+    simpleidn (0.1.1)
+      unf (~> 0.1.4)
     terminal-table (1.8.0)
       unicode-display_width (~> 1.1, >= 1.1.1)
     thread_safe (0.3.6)
     typhoeus (1.4.0)
       ethon (>= 0.9.0)
     tzinfo (1.2.7)
       thread_safe (~> 0.1)
+    unf (0.1.4)
+      unf_ext
+    unf_ext (0.0.7.7)
     unicode-display_width (1.7.0)
     yell (2.2.2)
     zeitwerk (2.4.0)

docs/guides/integration.md

@@ -91,9 +91,9 @@ The Event Consumer, as depicted above, implements the Event transformation logic
 establish this communication channel, the **Airplane Supplies** system declares a [gRPC](https://grpc.io/)
 service. In [`supplies_service.proto`](https://github.com/spine-examples/airport/blob/master/airplane-supplies/src/main/proto/spine/example/airport/supplies/supplies_service.proto):
 
-<?embed-code file="examples/airport/airplane-supplies/src/main/proto/spine/example/airport/supplies/supplies_service.proto" 
-             start="message Subscription*" 
-             end="}*"?>
+[//]: # <?embed-code file="examples/airport/airplane-supplies/src/main/proto/spine/example/airport/supplies/supplies_service.proto" 
+[//]: #              start="message Subscription*" 
+[//]: #              end="}*"?>
 ```proto
 message Subscription {
 
@@ -102,9 +102,9 @@ message Subscription {
     google.protobuf.Timestamp starting_from = 3;
 }
 ```
-<?embed-code file="examples/airport/airplane-supplies/src/main/proto/spine/example/airport/supplies/supplies_service.proto" 
-             start="enum EventType*" 
-             end="}*"?>
+[//]: # <?embed-code file="examples/airport/airplane-supplies/src/main/proto/spine/example/airport/supplies/supplies_service.proto" 
+[//]: #              start="enum EventType*" 
+[//]: #              end="}*"?>
 ```proto
 enum EventType {
     ALL = 0;
@@ -117,8 +117,8 @@ enum EventType {
 The **Airplane Supplies** system [implements](https://github.com/spine-examples/airport/blob/master/airplane-supplies/src/main/java/io/spine/example/airport/supplies/SuppliesEventProducer.java)
 the service and exposes it on an endpoint available to the **Takeoffs and Landings** system:
 
-<?embed-code file="examples/airport/airplane-supplies/src/main/java/io/spine/example/airport/supplies/SuppliesEventProducer.java" 
-             fragment="SuppliesEventProducer" ?>
+[//]: # <?embed-code file="examples/airport/airplane-supplies/src/main/java/io/spine/example/airport/supplies/SuppliesEventProducer.java" 
+[//]: #              fragment="SuppliesEventProducer" ?>
 ```java
 public final class SuppliesEventProducer extends SuppliesEventProducerImplBase {
 ...
@@ -145,8 +145,8 @@ an&nbsp;[event consumer](https://github.com/spine-examples/airport/blob/master/t
 which constructs a subscription and maintains it as long as the system needs to receive more events.
 The consumer broadcasts the received Events via an instance of [`ThirdPartyContext`](https://spine.io/core-java/reference/server/io/spine/server/integration/ThirdPartyContext.html):
 
-<?embed-code file="examples/airport/takeoffs-and-landings/src/main/java/io/spine/example/airport/tl/supplies/SuppliesEventConsumer.java" 
-             fragment="onNext" ?>
+[//]: # <?embed-code file="examples/airport/takeoffs-and-landings/src/main/java/io/spine/example/airport/tl/supplies/SuppliesEventConsumer.java" 
+[//]: #              fragment="onNext" ?>
 ```java
 @Override
 public void onNext(SuppliesEvent event) {
@@ -168,9 +168,9 @@ The [`AircraftAggregate`](https://github.com/spine-examples/airport/blob/master/
 reacts on those events. Note that all the events published through `ThirdPartyContext` are always
 `external`, so should be the subscriber and reactor methods.
 
-<?embed-code file="examples/airport/takeoffs-and-landings/src/main/java/io/spine/example/airport/tl/AircraftAggregate.java" 
-             start="@React" 
-            end="}"?>
+[//]: # <?embed-code file="examples/airport/takeoffs-and-landings/src/main/java/io/spine/example/airport/tl/AircraftAggregate.java" 
+[//]: #              start="@React" 
+[//]: #             end="}"?>
 ```java
 @React
 AircraftPreparedForFlight on(@External PreflightCheckComplete event) {
@@ -201,9 +201,9 @@ The Consumer consists of two parts: [`WeatherUpdateClient`](https://github.com/s
 and [`WeatherUpdateEndpoint`](https://github.com/spine-examples/airport/blob/master/takeoffs-and-landings/src/main/java/io/spine/example/airport/tl/weather/WeatherUpdateEndpoint.java).
 The client polls the pull-style API of the **Weather** system.
 
-<?embed-code file="examples/airport/takeoffs-and-landings/src/main/java/io/spine/example/airport/tl/weather/WeatherUpdateClient.java" 
-             start="private void fetchWeatherUpdates"
-             end="^    }"?>
+[//]: # <?embed-code file="examples/airport/takeoffs-and-landings/src/main/java/io/spine/example/airport/tl/weather/WeatherUpdateClient.java" 
+[//]: #              start="private void fetchWeatherUpdates"
+[//]: #              end="^    }"?>
 ```java
 private void fetchWeatherUpdates() {
     Instant lastEvent = lastEventTime;
@@ -230,9 +230,9 @@ private void fetchWeatherUpdates() {
 The endpoint handles the polled measurements and publishes them as Events in
 the **Takeoffs and Landings** context:
 
-<?embed-code file="examples/airport/takeoffs-and-landings/src/main/java/io/spine/example/airport/tl/weather/WeatherUpdateEndpoint.java" 
-             start="public void receiveNew"
-             end="^    }"?>
+[//]: # <?embed-code file="examples/airport/takeoffs-and-landings/src/main/java/io/spine/example/airport/tl/weather/WeatherUpdateEndpoint.java" 
+[//]: #              start="public void receiveNew"
+[//]: #              end="^    }"?>
 ```java             
 public void receiveNew(WeatherMeasurement measurement) {
     checkNotNull(measurement);
@@ -255,8 +255,9 @@ public void receiveNew(WeatherMeasurement measurement) {
 ```
 The [`FlightAggregate`](https://github.com/spine-examples/airport/blob/master/takeoffs-and-landings/src/main/java/io/spine/example/airport/tl/FlightAggregate.java)
 reacts on those events and changes its state as the result:
-<?embed-code file="examples/airport/takeoffs-and-landings/src/main/java/io/spine/example/airport/tl/FlightAggregate.java" 
-             fragment="TemperatureChanged" ?>
+
+[//]: # <?embed-code file="examples/airport/takeoffs-and-landings/src/main/java/io/spine/example/airport/tl/FlightAggregate.java" 
+[//]: #              fragment="TemperatureChanged" ?>
 ```java
 @React
 EitherOf2<FlightRescheduled, Nothing> on(@External TemperatureChanged event) {
@@ -302,8 +303,9 @@ for the [Boarding process](https://github.com/spine-examples/airport/blob/master
 The **Security Checks** API provides data for each passenger independently. The client polls
 the data and publishes many intermediate `PassengerBoarded` or `PassengerDeniedBoarding` external
 events via [`ThirdPartyContext`](https://spine.io/core-java/reference/server/io/spine/server/integration/ThirdPartyContext.html):
-<?embed-code file="examples/airport/takeoffs-and-landings/src/main/java/io/spine/example/airport/tl/passengers/PassengerClient.java" 
-             fragment="Fetch passengers" ?>
+
+[//]: # <?embed-code file="examples/airport/takeoffs-and-landings/src/main/java/io/spine/example/airport/tl/passengers/PassengerClient.java" 
+[//]: #              fragment="Fetch passengers" ?>
 ```java
 public void start() {
     while (active) {
@@ -332,8 +334,8 @@ The [Process Manager](https://github.com/spine-examples/airport/blob/master/take
 accumulates the Events and, once the whole *Flight* is boarded, emits a `BoardingComplete` event,
 which is later consumed by the&nbsp;[*Flight* Aggregate](https://github.com/spine-examples/airport/blob/master/takeoffs-and-landings/src/main/java/io/spine/example/airport/tl/FlightAggregate.java).
 
-<?embed-code file="examples/airport/takeoffs-and-landings/src/main/java/io/spine/example/airport/tl/passengers/BoardingProcman.java" 
-             fragment="BoardingProcman" ?>
+[//]: # <?embed-code file="examples/airport/takeoffs-and-landings/src/main/java/io/spine/example/airport/tl/passengers/BoardingProcman.java" 
+[//]: #              fragment="BoardingProcman" ?>
 ```java
 @React
 EitherOf2<BoardingComplete, Nothing> on(@External PassengerBoarded event) {