Fix/Support multiple subjects per course in DS 5.0 (#139)

* Add staging model with flattened academic subjects per course for DS 5

* Fix minimum/maximum credits type to float from int

According to the Ed-Fi docs, `MaximumAvailableCredits`, `MaximumAvailableCreditsConversion`,
`MinimumAvailableCredits`, and `MinimumAvailableCreditsConversion` should all be decimal types,
but other edu_edfi_source models (e.g. for course transcripts) keep track of similar fields as
floats.

Also, adjust indents for surrounding lines to maintain visual alignment.

* Document changes in CHANGELOG.md

* Move unreleased changes to right section in changelog

Author: alchenist

CHANGELOG.md

@@ -2,6 +2,8 @@
 ## New features
 ## Under the hood
 ## Fixes
+- Add handling of multiple academic subjects per course for DS 5.0 compatibility; new `stg_ef3__courses_academic_subjects` model and new `v_academic_subjects` columns in `base_ef3__courses` and `stg_ef3__courses` models.
+- Correctly cast minimum and maximum credits for courses to float instead of int.
 
 
 # edu_edfi_source v0.4.9

models/staging/edfi_3/base/base_ef3__courses.sql

@@ -15,18 +15,18 @@ renamed as (
         data_model_version,
         v:educationOrganizationReference:educationOrganizationId::int as ed_org_id,
         v:educationOrganizationReference:link:rel::string             as ed_org_type,
-        v:courseCode::string                    as course_code,
-        v:courseTitle::string                   as course_title,
-        v:courseDescription::string             as course_description,
-        v:dateCourseAdopted::date               as date_course_adopted,
-        v:highSchoolCourseRequirement::boolean  as is_high_school_course_requirement,
-        v:maxCompletionsForCredit::int         as max_completions_for_credit,
-        v:maximumAvailableCreditConversion::int as maximum_available_credit_conversion,
-        v:maximumAvailableCredits::int          as maximum_available_credits,
-        v:minimumAvailableCreditConversion::int as minimum_available_credit_conversion,
-        v:minimumAvailableCredits::int          as minimum_available_credits,
-        v:numberOfParts::int                    as number_of_parts,
-        v:timeRequiredForCompletion::int        as time_required_for_completion,
+        v:courseCode::string                      as course_code,
+        v:courseTitle::string                     as course_title,
+        v:courseDescription::string               as course_description,
+        v:dateCourseAdopted::date                 as date_course_adopted,
+        v:highSchoolCourseRequirement::boolean    as is_high_school_course_requirement,
+        v:maxCompletionsForCredit::int            as max_completions_for_credit,
+        v:maximumAvailableCreditConversion::float as maximum_available_credit_conversion,
+        v:maximumAvailableCredits::float          as maximum_available_credits,
+        v:minimumAvailableCreditConversion::float as minimum_available_credit_conversion,
+        v:minimumAvailableCredits::float          as minimum_available_credits,
+        v:numberOfParts::int                      as number_of_parts,
+        v:timeRequiredForCompletion::int          as time_required_for_completion,
         {{ extract_descriptor('v:academicSubjectDescriptor::string') }}            as academic_subject,
         {{ extract_descriptor('v:careerPathwayDescriptor::string') }}              as career_pathway,
         {{ extract_descriptor('v:courseDefinedByDescriptor::string') }}            as course_defined_by,
@@ -42,6 +42,7 @@ renamed as (
         v:learningStandards    as v_learning_standards,
         v:levelCharacteristics as v_level_characteristics,
         v:offeredGradeLevels   as v_offered_grade_levels,
+	v:academicSubjects     as v_academic_subjects,
 
         -- edfi extensions
         v:_ext as v_ext

models/staging/edfi_3/stage/stg_ef3__courses__academic_subjects.sql

@@ -0,0 +1,14 @@
+with stg_courses as (
+    select * from {{ ref('stg_ef3__courses') }}
+), 
+flattened as (
+    select
+        tenant_code,
+        api_year,
+        k_course,
+        {{ extract_descriptor('value:academicSubjectDescriptor::string') }} as academic_subject
+    from stg_courses,
+        lateral flatten(input => v_academic_subjects)
+)
+select *
+from flattened