This document provides an introduction and overview of MongoTalk and Voyage, two Smalltalk libraries for interacting with MongoDB databases. It demonstrates how to install, configure, and perform basic operations like creating databases and collections, inserting, updating, deleting and querying documents with both libraries. It also shows how to customize mappings and relationships when using Voyage.

1. MongoTalk/Voyage
by Nico and Esteban
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2. Pre-requisites
• MongoDB installed and running
• Pharo 2.0
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3. Getting MongoTalk
Gofer it
smalltalkhubUser:‘MongoTalkTeam’ project:
‘mongotalk’;
configurationOf:‘MongoTalk’;
load.
ConfigurationOfMongoTalk load.
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4. What is Mongo?
• NoSQL database
• Opensource
• Document oriented
• Powerful query language
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5. MongoTalk basics
• MongoTalk is a driver for Mongo
• JSON/BSON (dictionaries)
• Mongo databases, collections and
documents
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6. Let’s play with it!
• Creating a database
• Creating a collection
• Manipulating some documents
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7. Databases and
collections
| mongo db users |
mongo := Mongo default open.
“db is created on the fly”
db := mongo databaseNamed:‘esug’.
“Same goes for collections”
users := db addCollection:‘users’.
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8. Insert/Update/Delete
users add: {
‘name’ -> ‘nico’.
‘age’ -> 27} asDictionary.
users
update: { ‘name’ -> ‘nico’ } asDictionary
with: {
‘name’ -> ‘nico’.
‘age’ -> 28 } asDictionary.
users delete: {‘name’ -> ‘nico’ } asDictionary.
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9. Simple queries
“Use the traditional collection enumerating
methods, with dictionaries”
users select: {‘name’ -> ‘nico’} asDictionary.
users detect: {‘age’ -> 28} asDictionary.
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10. Limit, offset, order
users
select: {‘name’ -> ‘nico’} asDictionary
limit: 5
offset: 10
order: {‘age’ -> 1} asDictionary
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11. MongoQueries
users select: [ :each | each name = ‘nico’ ].
users detect: [ :each |
(each name = ‘nico’) & (each age > 25) ]
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12. ...Voyage
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13. Install
Gofer it
smalltalkhubUser:‘estebanlm’ project:‘Voyage’;
configurationOf:‘VoyageMongo’;
load.
ConfigurationOfVoyageMongo load.
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14. Singleton vs. Instanced
| repository |
repository :=VOMongoRepository
host:‘localhost’
database:‘esug’.
repository enableSingleton.
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15. Basic operation
| user |
user := User new
name:‘You’;
save.
user age:‘shhh’.
user save.
user remove.
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16. Querying (1)
User selectAll.
User selectOne: [ :each | each name = ‘you’ ].
User selectMany: [ :each | each name = ‘you’ ].
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17. Querying (2)
User selectOne: {
#name -> ‘you’ } asDictionary.
User selectMany: {
#name -> ‘you’ } asDictionary.
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18. Querying (3)
User
selectMany: { #name -> ‘you’ } asDictionary
sortBy: { #name ->VOOrder ascending }
limit: 10
offset: 10.
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19. Querying (4)
User
selectMany: {
#name -> {
‘$regex’ -> ‘^y.*’.
‘$options’ -> ‘i’ } asDictionary } asDictionary
sortBy: { #name ->VOOrder ascending }
limit: 10
offset: 10.
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20. References
• Embedded objects
• Regular references
• Cyclic
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21. Customize (1)
User class>>#mongoContainer
<mongoContainer>
^VOMongoContainer new
collectionName:‘users’;
kind: User;
enableMissingContent;
yourself
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22. Customize (2)
User class>>#mongoName
<mongoDescription>
^VOMongoToOneDescription new
attributeName:‘name’;
beLazy;
yourself.
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23. Customize (3)
User class>>#mongoGroups
<mongoDescription>
^VOMongoToManyDescription new
attributeName:‘groups’;
beEager;
kind: Group;
kindCollection: Set;
convertNullTo: [ MissingGroup new ];
yourself.
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24. Customize (4)
User class>>#mongoName
<mongoDescription>
^VOMongoToOneDescription new
accessor: (MAPluggableAccessor
read: [ :user | user nameForPersist ]
write: [ :user :v | user name: v ]);
yourself.
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