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+# Camel Spring Boot Demo Routes
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+
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+This is a collection of demonstrational routes to accompany Apache Camel training.
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+
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+In order to choose which problem you want to explore and test, start the Spring Boot application with the system property `camel.problem` set to one of the available values:
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+
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+* `intro`
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+* `database`
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+* `jms`
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+* `kafka`
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+* `rest-service`
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+* `rest-client`
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+* `http-client`
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+* `health`
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+* `bookstore`
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+
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+See more on individual problems (and the requirements to run them) below.
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+
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+The main class, `Application`, is your classic Spring Boot application starter.
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+
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+The class that performs the problem configuration by loading specific routes is `CamelContextConfig`.
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+
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+For a Maven plug-in-assisted start-up, you can select the problem as follows:
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+
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+ $ mvn spring-boot:run -Dspring-boot.run.jvmArguments="-Dcamel.problem=FOO"
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+
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+After packaging the application, you can run a problem as follows:
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+
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+ $ mvn spring-boot:repackage
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+ ...
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+ $ java -Dcamel.problem=FOO -jar ./target/demo-1.0-SNAPSHOT.jar
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+
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+## Bookstore
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+
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+Bookstore has three routes loading data from `data/bookstore/` directory:
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+
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+* `books.xml` (overridable by `books.file` property)
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+* `users.csv` (can be overriden by app property `users.file`)
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+* `orders.json` (property `orders.file` can override this)
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+
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+The three file consumer routes are configured with `noop` option, so the files are never removed.
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+
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+### Book Catalog (`bookLoader`)
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+
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+The `books.xml` file represents a bookstore catalog, which is loaded, split into individual books, then unmarshaled from XML into instances of `Book` object.
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+Two filters then remove any books older than 2004 and any books written by "George R. R. Martin" (supposing we can not sell those due to contractual obligations).
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+The last processor in the route adds each book to an internal singleton bean where it can be further accessed by other routes in need of enrichment.
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+
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+### User Catalog (`userLoader`)
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+
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+The `users.csv` file is a user catalog, loaded, split into individual records by newline, and the first row containing column headers is ignored.
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+The remaining records are unmarshaled from CSV into instances of `User` object.
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+There is a spin-off step where we invoke the `userAggregator` route, which is discussed below.
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+
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+Lastly, we try to add the user to the singleton bean which, like with books, represents the user catalog and is available to other routes for enrichment.
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+Note that the bean invocation is not specifying the exact method, unlike with the book catalog - this is just to demonstrate Camel's automatic method detection.
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+
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+The seeming complication in unmarshaling is there because one of the rows in the CSV file is deliberately corrupt and will not parse.
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+Without splitting first and then unmarshaling, the entire file would be read multiple times and valid records would cause duplicates in the user catalog, not to mention needless overhead.
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+
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+### Team Aggregation (`userAggregator`)
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+
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+The route consuming from `direct:aggregateByTeam` is showcasing aggregation on a field of the body object, and a simple aggregation strategy which has a limit of 10 users per team and will complete if no new users have been seen for over 1.5s in each aggregation group.
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+
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+After finishing the aggregation it marshals the team into JSON and writes it into `data/out/teams.json` file for later inspection.
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+
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+### Order Processor (`orderLoader`)
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+
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+The order processor loads from `orders.json` file, unmarshals the contents into a `List` of `Order` objects, and then converts each order into an instance of a fully-blown `FulfillmentOrder` class which is suitable for fulfillment.
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+
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+Because the object is initially empty (with the exception of user ID and book title), we need to enrich the data and this is performed using the `enrich()` EIP. The `orderEnrichment` route is discussed below.
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+
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+After `FulfillmentOrder` objects are enriched, they are marshaled back into JSON and written to `data/out/orders.json`.
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+
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+### Order Enrichment (`orderEnrichment`)
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+
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+The route invokes two different methods in `FulfillmentEnrichment` class - `enrichUser` and `enrichBook`, each of which contacts its catalog in order to obtain data about the user (identified by the user ID number) or the book (identified by its title), respectively.
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+
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+Because order enrichment may occur before data is available, the route is configured with an exception handler for the two `NotFoundException` exceptions that may occur, which logs the error, sets redelivery delay to 1.5s, and configures up to 10 redelivery attempts.
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