$addfield with three $cond mongodb - mongodb

Question

I have this output data from aggregation $lookup
[
{
_id: 1,
name: "Abraham",
class: "V",
question_answered: [
{
id: "quest1",
answer: "A",
score: 10,
question: {
soal: "apa judul lagu?",
correct_answer: "A",
type_question: "Essay"
}
},
{
id: "quest2",
answer: "C",
score: null,
question: {
soal: "apa judul lagu B?",
correct_answer: "B",
type_question: "Essay"
}
},
{
id: "quest3",
answer: "C",
score: 10,
question: {
soal: "apa judul lagu C?",
correct_answer: "C",
type_question: "essay_pg"
}
},
]
},
{
_id: 2,
name: "Brenda",
class: "V",
question_answered: [
{
id: "quest1",
answer: "A",
score: 10,
question: {
soal: "apa judul lagu A?",
correct_answer: "A",
type_question: "Essay"
}
},
{
id: "quest2",
answer: "C",
score: 0,
question: {
soal: "apa judul lagu B?",
correct_answer: "B",
type_question: "Essay"
}
}
]
}
]
I need to add additional field formated_status_evaluation_essay and formated_status_evaluation_essay_pg in each data that i get with some few condition if,elseif, else. i'll give one of example addfield condition, more or less like this one:
IF(question_answered.question.type_question == 'Essay' and no score is
null in every essay type question) then,
formated_status_evaluation_essay = "complete scoring".
ELSEIF(there's essay type question and have at least one null score)
then, formated_status_evaluation_essay = "Incomplete scoring"
ELSEIF(if theres no essay type question) then,
formated_status_evaluation_essay = "no question"
Same goes to formated_status_evaluation_essay_pg. The output that i expected is like this.
[
{
_id: 1,
name: "Abraham",
class: "V",
question_answered: [....],
formated_status_evaluation_essay: incomplete scoring,
formated_status_evaluation_essay_pg: complete scoring,
},
{
_id: 2,
name: "Brenda",
class: "V",
question_answered: [....],
formated_status_evaluation_essay: complete scoring,
formated_status_evaluation_essay_pg: no question,
}
]
The explanation about the output.
_id:1, get evaluation_essay incomplete because it has one object that contain null score. But the evaluation_essay_pg contain complete
scoring because essay_pg type all of it have a score.
_id:2, evaluation_essay is complete because all question with type essay have a score. But essay_pg contain no question because theres no essay_pg type in question_answer.question.type_question.
I've tried this and still confuse to code three condition like i've explained before. I put code like this in the end of $lookup aggregation.
{
'$addFields': {
'formated_status_evaluation_essay': {
'$cond': [
{
'$and': [
{'$$question_answer.question.type_soal ':
'essay'},
{'$$question_answer.nilai':{$ne:null}},
]
},
'already scoring',
'havent scoring'
]
}
}
}
i almost get what i expected but, seems still have a wrong syntax i wrote. I would be very thankfull if you guys can help me. Been working for two days still got no answer.

Answer 1

Try to make the code a little bit more readable by using $switch to handle the branching.
db.collection.aggregate([
{
"$addFields": {
"formated_status_evaluation_essay": {
"$filter": {
"input": "$question_answered",
"as": "q",
"cond": {
$eq: [
"$$q.question.type_question",
"Essay"
]
}
}
},
"formated_status_evaluation_essay_pg": {
"$filter": {
"input": "$question_answered",
"as": "q",
"cond": {
$eq: [
"$$q.question.type_question",
"essay_pg"
]
}
}
}
}
},
{
"$addFields": {
"formated_status_evaluation_essay": {
"$switch": {
"branches": [
{
"case": {
$and: [
{
"$allElementsTrue": [
{
"$map": {
"input": "$formated_status_evaluation_essay.score",
"as": "s",
"in": {
$ne: [
"$$s",
null
]
}
}
}
]
},
{
$ne: [
{
$size: "$formated_status_evaluation_essay"
},
0
]
}
]
},
"then": "complete scoring"
},
{
"case": {
"$anyElementTrue": [
{
"$map": {
"input": "$formated_status_evaluation_essay.score",
"as": "s",
"in": {
$eq: [
"$$s",
null
]
}
}
}
]
},
"then": "incomplete scoring"
}
],
default: "no question"
}
},
"formated_status_evaluation_essay_pg": {
"$switch": {
"branches": [
{
"case": {
$and: [
{
"$allElementsTrue": [
{
"$map": {
"input": "$formated_status_evaluation_essay_pg.score",
"as": "s",
"in": {
$ne: [
"$$s",
null
]
}
}
}
]
},
{
$ne: [
{
$size: "$formated_status_evaluation_essay_pg"
},
0
]
}
]
},
"then": "complete scoring"
},
{
"case": {
"$anyElementTrue": [
{
"$map": {
"input": "$formated_status_evaluation_essay_pg.score",
"as": "s",
"in": {
$eq: [
"$$s",
null
]
}
}
}
]
},
"then": "incomplete scoring"
}
],
default: "no question"
}
}
}
}
])
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