In this challenge, you will implement the remaining methods in the MovieService for retrieving a list of movies:
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getByGenre - should return a paginated list of movies that are listed in a particular Genre
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getForActor - should return a paginated list of movies that a particular Person has acted in
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getForDirector - should return a paginated list of movies that a particular Person has directed
These methods are very similar to the all() method which returns a full list, but with a different pattern in the MATCH clause.
$skip and $limit from the request as parameters and string-replace the field to order for sort and order direction (as those cannot be parameterized).Unresolved directive in lesson.adoc - include::https://raw.githubusercontent.com/neo4j-graphacademy/llm-chatbot-python/11-movie-lists/src/main/java/neoflix/services/MovieService.java[tag=all]For each subtask, we will provide you with the pattern required to run in the Cypher statement, plus any additional parameters that are required for the query to run.
All you need to do is take the code from the all() method and modify the pattern in the first line of the Cypher statement in the first argument of the tx.run() call, then if necessary add the additional parameters to the second argument.
If you get stuck at any point, you can click to reveal the completed solution or skip to the bottom for instructions on how to checkout the branch with the working solution.
getByGenre
The getByGenre() method returns a paginated list of movies that are listed within a certain genre.
Unresolved directive in lesson.adoc - include::https://raw.githubusercontent.com/neo4j-graphacademy/llm-chatbot-python/main/src/main/java/neoflix/services/MovieService.java[tag=getByGenre]Update the getByGenre() method to use the following Cypher Pattern:
MATCH (m:Movie)-[:IN_GENRE]->(:Genre {name: $name})The tx.run() call will need to include the name parameter, which represents the name of the genre.
Click to reveal the completed getByGenre() method
Find the getByGenre() method in src/main/java/neoflix/services/MovieService.java and modify the function to find a list of movies by genre.
Unresolved directive in lesson.adoc - include::https://raw.githubusercontent.com/neo4j-graphacademy/llm-chatbot-python/11-movie-lists/src/main/java/neoflix/services/MovieService.java[tag=getByGenre]getForActor
The getForActor() method returns a paginated list of movies that a person has acted in.
Unresolved directive in lesson.adoc - include::https://raw.githubusercontent.com/neo4j-graphacademy/llm-chatbot-python/main/src/main/java/neoflix/services/MovieService.java[tag=getForActor]Find the getForActor() method in src/main/java/neoflix/services/MovieService.java and modify the function to find a list of movies by actor.
The pattern required in the MATCH clause will be:
MATCH (:Person {tmdbId: $id})-[:ACTED_IN]->(m:Movie)You will have to include the additional parameter id - The tmdbId property relating to the actor.
Click to reveal the completed getForActor() method
Unresolved directive in lesson.adoc - include::https://raw.githubusercontent.com/neo4j-graphacademy/llm-chatbot-python/11-movie-lists/src/main/java/neoflix/services/MovieService.java[tag=getForActor]getForDirector
The getForDirector() method returns a paginated list of movies that a person has directed.
Unresolved directive in lesson.adoc - include::https://raw.githubusercontent.com/neo4j-graphacademy/llm-chatbot-python/main/src/main/java/neoflix/services/MovieService.java[tag=getForDirector]Find the getForDirector() method in src/main/java/neoflix/services/MovieService.java and modify the function to find a list of movies by director.
The pattern required in the MATCH clause will be:
MATCH (:Person {tmdbId: $id})-[:DIRECTED]->(m:Movie)You will have to include the additional parameter id - The tmdbId property relating to the director.
Click to reveal the completed getForDirector() method
Unresolved directive in lesson.adoc - include::https://raw.githubusercontent.com/neo4j-graphacademy/llm-chatbot-python/11-movie-lists/src/main/java/neoflix/services/MovieService.java[tag=getForDirector]Testing
To test that this functionality has been correctly implemented, run the following code in a new terminal session:
mvn test -Dtest=neoflix._11_MovieListTestThe test file is located at src/test/java/neoflix/_11_MovieListTest.java.
Are you stuck? Click here for help
If you get stuck, you can see a working solution by checking out the 11-movie-lists branch by running:
git checkout 11-movie-listsYou may have to commit or stash your changes before checking out this branch. You can also click here to expand the Support pane.
Verifying the Test
1. How many films has Francis Ford Copolla directed?
As part of the test suite, the test titled should find films directed by Francis Ford Coppola logs out the number of results returned from the API for films directed by Francis Ford Copolla.
Enter the number in the box below and click Check Answer.
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✓ 16
Hint
You can also find the answer by running the following Cypher statement:
MATCH (p:Person {tmdbId: "1776"})
RETURN count { (p)-[:DIRECTED]->() }Copy the answer without any quotes or whitespace.
Lesson Summary
In this Challenge, you modified the functions in the MovieService to return lists of movies.
In the next Challenge, we will implement the findById() method.