Move all the pipelines together

Author: mikehquan19

uploader/pipelines/trends.go

@@ -0,0 +1,149 @@
+package pipelines
+
+import (
+	"go.mongodb.org/mongo-driver/bson"
+	"go.mongodb.org/mongo-driver/mongo"
+)
+
+// TrendsCourseSectionsPipeline links course documents to their section records for trends-specific aggregation.
+var TrendsCourseSectionsPipeline = mongo.Pipeline{
+	bson.D{
+		{Key: "$lookup",
+			Value: bson.D{
+				{Key: "from", Value: "sections"},
+				{Key: "localField", Value: "sections"},
+				{Key: "foreignField", Value: "_id"},
+				{Key: "as", Value: "sections"},
+			},
+		},
+	},
+	bson.D{
+		{Key: "$project",
+			Value: bson.D{
+				{Key: "subject_prefix", Value: 1},
+				{Key: "course_number", Value: 1},
+				{Key: "sections", Value: 1},
+			},
+		},
+	},
+	bson.D{
+		{Key: "$unwind",
+			Value: bson.D{
+				{Key: "path", Value: "$sections"},
+				{Key: "preserveNullAndEmptyArrays", Value: false},
+			},
+		},
+	},
+	bson.D{
+		{Key: "$group",
+			Value: bson.D{
+				{Key: "_id",
+					Value: bson.D{
+						{Key: "$concat",
+							Value: bson.A{
+								"$subject_prefix",
+								"$course_number",
+							},
+						},
+					},
+				},
+				{Key: "sections", Value: bson.D{{Key: "$addToSet", Value: "$sections"}}},
+			},
+		},
+	},
+}
+
+// TrendsProfSectionsPipeline denormalizes professor records with their taught sections for trends-specific aggregation.
+var TrendsProfSectionsPipeline = mongo.Pipeline{
+	bson.D{
+		{Key: "$lookup",
+			Value: bson.D{
+				{Key: "from", Value: "sections"},
+				{Key: "localField", Value: "sections"},
+				{Key: "foreignField", Value: "_id"},
+				{Key: "as", Value: "sections"},
+			},
+		},
+	},
+	bson.D{
+		{Key: "$project",
+			Value: bson.D{
+				{Key: "first_name", Value: 1},
+				{Key: "last_name", Value: 1},
+				{Key: "sections", Value: 1},
+			},
+		},
+	},
+}
+
+// TrendsCourseProfSectionsPipeline links combination of professor and course to the sections for trends-specific aggregation.
+var TrendsCourseProfSectionsPipeline = mongo.Pipeline{
+	bson.D{
+		{Key: "$lookup",
+			Value: bson.D{
+				{Key: "from", Value: "sections"},
+				{Key: "localField", Value: "sections"},
+				{Key: "foreignField", Value: "_id"},
+				{Key: "as", Value: "sections"},
+			},
+		},
+	},
+	bson.D{
+		{Key: "$project",
+			Value: bson.D{
+				{Key: "subject_prefix", Value: 1},
+				{Key: "course_number", Value: 1},
+				{Key: "sections", Value: 1},
+			},
+		},
+	},
+
+	bson.D{
+		{Key: "$unwind",
+			Value: bson.D{
+				{Key: "path", Value: "$sections"},
+				{Key: "preserveNullAndEmptyArrays", Value: false},
+			},
+		},
+	},
+	bson.D{
+		{Key: "$lookup",
+			Value: bson.D{
+				{Key: "from", Value: "professors"},
+				{Key: "localField", Value: "sections.professors"},
+				{Key: "foreignField", Value: "_id"},
+				{Key: "as", Value: "professors"},
+			},
+		},
+	},
+	bson.D{
+		{Key: "$unwind",
+			Value: bson.D{
+				{Key: "path", Value: "$professors"},
+				{Key: "preserveNullAndEmptyArrays", Value: false},
+			},
+		},
+	},
+
+	bson.D{
+		{Key: "$group",
+			Value: bson.D{
+				{Key: "_id",
+					Value: bson.D{
+						{Key: "$concat",
+							Value: bson.A{
+								"$subject_prefix",
+								"$course_number",
+								" ",
+								"$professors.first_name",
+								" ",
+								"$professors.last_name",
+							},
+						},
+					},
+				},
+				{Key: "sections", Value: bson.D{{Key: "$addToSet", Value: "$sections"}}},
+			},
+		},
+	},
+}