MongoUtils
Mongodb helper functions, document and pipeline builder.
Helpers
ParseObjectID
Parse object id from string.
ParseObjectID(id string) *primitive.ObjectID
IsValidObjectId
Check if object id is valid and not zero.
IsValidObjectId(id *primitive.ObjectID) bool
Doc Builder
Document builder is a helper type for creating mongo document (primitive.D) with chained methods.
import "github.com/bopher/mongoutils"
doc := mongoutils.NewDoc()
doc.
Add("name", "John").
Add("nick", "John2").
Array("skills", "javascript", "go", "rust", "mongo")
fmt.Println(doc.Build())
// -> {
// "name": "John",
// "nick": "John2",
// "skills": ["javascript","go","rust","mongo"]
// }
Doc Methods
Add
Add new element.
// Signature:
Add(k string, v interface{}) MongoDoc
// Example:
doc.Add("name", "Kim")
Doc
Add new element with nested doc value.
// Signature:
Doc(k string, cb func(d MongoDoc) MongoDoc) MongoDoc
// Example:
doc.Doc("age", func(d mongoutils.MongoDoc) mongoutils.MongoDoc {
d.Add("$gt", 20)
d.Add("$lte", 30)
return d
}) // -> { "age": { "$gt": 20, "$lte": 30 } }
Array
Add new element with array value.
// Signature:
Array(k string, v ...interface{}) MongoDoc
// Example:
doc.Array("skills", "javascript", "golang") // -> { "skills": ["javascript", "golang"] }
Nested
Add new nested element.
// Signature:
Nested(root string, k string, v interface{}) MongoDoc
// Example:
doc.Nested("$set", "name", "Jack") // { "$set": { "name": "Jack" } }
NestedDoc
Add new nested element with doc value.
// Signature:
NestedDoc(root string, k string, cb func(d MongoDoc) MongoDoc) MongoDoc
// Example:
doc.NestedDoc("$set", "address", func(d mongoutils.MongoDoc) mongoutils.MongoDoc {
d.
Add("city", "London").
Add("street", "12th")
return d
}) // -> { "$set": { "address": { "city": "London", "street": "12th" } } }
NestedArray
Add new nested element with array value.
// Signature:
NestedArray(root string, k string, v ...interface{}) MongoDoc
// Example:
doc.NestedArray("skill", "$in", "mongo", "golang") // -> { "skill": { "$in": ["mongo", "golang"] } }
Regex
Add new element with regex value.
// Signature:
Regex(k string, pattern string, opt string) MongoDoc
// Example:
doc.Regex("full_name", "John.*", "i") // -> { "full_name": { pattern: "John.*", options: "i" } }
Map
Creates a map from the elements of the Doc.
Map() primitive.M
Build
Generate mongo doc.
Build() primitive.D
Pipeline Builder
Pipeline builder is a helper type for creating mongo pipeline ([]primitive.D) with chained methods.
import "github.com/bopher/mongoutils"
pipe := mongoutils.NewPipe()
pipe.
Add(func(d mongoutils.MongoDoc) mongoutils.MongoDoc{
d.Nested("$match", "name", "John")
return d
}).
Group(func(d mongoutils.MongoDoc) mongoutils.MongoDoc{
d.
Add("_id", "$_id").
Nested("name", "$first", "$name")
Nested("total", "$sum", "$invoice")
return d
})
fmt.Println(pipe.Build())
// -> [
// { "$match": { "name": "John"} },
// { "$group": {
// "_id": "$_id"
// "name": { "$first": "$name" },
// "total": { "$sum": "$invoice" }
// }}
// ]
Pipeline Methods
Add
Add new Doc.
// Signature:
Add(cb func(d MongoDoc) MongoDoc) MongoPipeline
// Example:
pipe.Add(func(d mongoutils.MongoDoc) mongoutils.MongoDoc{
d.Nested("$match", "name", "John")
return d
}) // -> [ {"$match": { "name": "John"}} ]
Lookup
Add $lookup stage.
// Signature:
Lookup(from string, local string, foreign string, as string) MongoPipeline
// Example:
pipe.Lookup("users", "user_id", "_id", "user")
// -> [
// {"$lookup": {
// "from": "users",
// "localField": "user_id",
// "foreignField": "_id",
// "as": "user"
// }}
// ]
Unwind
Add $unwind stage.
// Signature:
Unwind(path string, prevNullAndEmpty bool) MongoPipeline
// Example:
pipe.Unwind("services", true)
// -> [
// {"$unwind": {
// "path": "services",
// "preserveNullAndEmptyArrays": true,
// }}
// ]
Unwrap
Get first item of array and insert to doc using $addFields stage. When using lookup result returns as array, use this helper to unwrap lookup result as field.
// Signature:
Unwrap(field string, as string) MongoPipeline
// Example:
pipe.
Lookup("users", "user_id", "_id", "__user").
Unwrap("$__user", "user")
// -> [
// { "$lookup": {
// "from": "users",
// "localField": "user_id",
// "foreignField": "_id",
// "as": "user"
// }},
// { "$addFields": { "user" : { "$first": "$__user" } } }
// ]
Group
Add $group stage.
// Signature:
Group(cb func(d MongoDoc) MongoDoc) MongoPipeline
// Example:
pipe.
Group(func(d mongoutils.MongoDoc) mongoutils.MongoDoc{
d.
Add("_id", "$_id").
Nested("name", "$first", "$name").
Nested("total", "$sum", "$invoice")
return d
})
// -> [
// { "$group": {
// "_id": "$_id"
// "name": { "$first": "$name" },
// "total": { "$sum": "$invoice" }
// }}
// ]
ReplaceRoot
Add $replaceRoot stage.
// Signature:
ReplaceRoot(v interface{}) MongoPipeline
// Example:
pipe.ReplaceRoot("$my_root")
// -> [{ "$replaceRoot": {"newRoot": "$my_root" } }]
MergeRoot
Add $replaceRoot stage with $mergeObjects operator.
// Signature:
MergeRoot(fields ...interface{}) MongoPipeline
// Example:
pipe.MergeRoot("$my_root", "$$ROOT")
// -> [
// {
// "$replaceRoot": {
// "newRoot": { "mergeObjects": ["$my_root", "$$ROOT"] }
// }
// }
// ]
UnProject
Generate $project stage to remove fields from result.
// Signature:
UnProject(fields ...string) MongoPipeline
// Example:
pipe.UnProject("my_root", "__user")
// -> [
// { "$project": { "my_root": 0, "__user": 0 } }
// ]
Build
Generate mongo pipeline.
Build() mongo.Pipeline
