SpenceJs: Mongo Repos

Introduction

Spencer repos are a way to share the most common logic of your data layer, making it easy to do the most common queries or persistence operations.

• easy to use
• simple (only 500 lines of code)
• offers access to the full power of the mongo driver to the user when they need to do more complex queries such as aggregation pipelines. No point building an abstraction over that
• manage sideeffects in a decoupled way by using spence-events. Bootstrap your Event Driven Architecture!
• very similar api to relational database using knex means you can migrate easily if you need to.

Getting Started

For saving documents like:

{
      _id: ObjectId("507f1f77bcf86cd799439011"),
      aVal: "foobar",
      manyVals: [1,2,3],
      createdAt: "2019-12-22T07:27:33Z",
      updatedAt: "2019-12-22T07:27:33Z"
}

Intialize a repo like this:

function initExampleRepo() {
  return repoFactory({
    name: "examples",
    entityName: "example",
    defaultProjection: {
      _id: 1,
      aVal: 1,
      manyVals: 1,
      createdAt: 1,
      updatedAt: 1,
    }
  });
}

Happy databasing!

await mongoFactory({log: console, config: {mongoConnection: "mongodb://localhost:27017"}});
const exampleRepo = initExampleRepo();
const insertedDoc = await exampleRepo.insert({aVal: "foobar", manyVals: []}); 
console.info(await exampleRepo.findById(insertedDoc._id));

Output

{
      _id: ObjectId("507f1f77bcf86cd799439011"),
      aVal: "foobar",
      manyVals: [],
      createdAt: "2020-06-29T12:22:56Z",
      updatedAt: "2020-06-29T12:22:56Z"
}

Repos

Repos are extensible adapters over a collection that provide operations to add or change docs. It is very easy to add capabilities like multitenant support or soft delete with just a few lines of code.

When creating a repo first define the collection and how you want to interact with it. Then you can add custom extensions.

Example coming soon

Collections

name (required)

The name of the collection in the db

entityName

The name of a single entity

defaultProjection

The default set keys to retrieve for a repo operation.

timestampKeys

spence automatically generates timestamp keys createdAt & updatedAt. Overriding them by suppying a map like

{
      "createdAt": "creationDate",
      "updatedAt": "modificationDate"
}

mutable

defaults to true. if false the updatedAt timestamp will not be set.

mockIdGenerator

Set this value so that your spence-factories can generate ids of the correct type without persisting data to the db.

Extensions

Extensions can be passed into the Repo. They can override the implementation of any of the operaitons listed below. They can be used for modifying any of the arguments then delgating, or completely reimplementing an operation.

RepoRegistry

The repo registry caches intializations of repo so that there is only ever one created in the entire system across all modules that make up the system. Enables the reposPlugin

Fastify Plugins

spence is made with fastify in mind. That means it comes out of the box with plugins that make using fastify easy.

  const { mongodbPlugin, reposPlugin } = require('@spencejs/spence-mongo-repos');
  
  fastify.register(require("fastify-env"); // spence-mongo-repos plugins assumes that fastify.config attribute has been set such as by using fastify-env
  fastify.register(mongodbPlugin); // initializes the mongo db. Uses the folowing config from fastify.config: { mongoConnection, nodeEnv, debug }
  
  fastify.register(reposPlugin); // attaches req.repos which contains all initialized repos to the request object

Operations

find({ filter: Filter, sort: Sort, limit: integer, skip: integer }, projection: Projection): Promise<object[]>

Find a set of documents matching the filter

• filter is a regular mongo query object
• limit is the max number fo docs to return
• skip is the number of docs to skip
• sort is the way to sort things. Use the regular mongo sort object
• projection is a regular mongo projection object. Defaults to your default.

findById(_id: string, projection: Projection): Promise<object>

Finds a single document by id

• _id to find
• projection is a regular mongo projection object. Defaults to your default.

findOne({filter: Filter, sort: Sort}, projection: Projection): Promise<object | undefined>

Finds the first document to match the filter and sort specified.

• filter is a regular mongo query object
• sort is the way to sort things. Use the regular mongo sort object
• projection is a regular mongo projection object. Defaults to your default.

count({filter: Filter}): Promise<integer>

Counts the documents matching the filter

• filter is a regular mongo query object

insert(val: object, projection: Projection): Promise<object>

Inserts the document. Returns the inserted document matching the projection. Sets createdAt & updatedAt. Dispatches a created event

• val to insert
• projection is a regular mongo projection object. Defaults to your default.

insertMany(vals: object[], projection: Projection): Promise<object[]>

Inserts many documents. Returns the inserted document matching the projection. Sets createdAt & updatedAt. Dispatches a created events

• val to insert
• projection is a regular mongo projection object. Defaults to your default.

findOrInsert(val: object, naturalKey: string, projection: Projection): Promise<object>

Find or insert the value. The second argument is the natural key. Sets createdAt & updatedAt if an insert occurs. Dispatches a created events if an insert occurs.

• val to insert
• naturalKey. the attribute within the val that should be used as a naturalKey.
• projection is a regular mongo projection object. Defaults to your default.

update(_id*: string, val: object, projection: Projection): Promise<object>

Update by id. Updates all the fields for you. Sets updatedAt. Dispatches a updated events.

• _id to update
• val to set
• projection is a regular mongo projection object. Defaults to your default.

updateUsingFilter({filter: Filter}, val*: object, projection: Projection): Promise<object[]>

Update using filters. Updates all the fields for you. Sets updatedAt. Dispatches a updated events.

• filter is a regular mongo query object. All docs matching the filters.
• val to set
• projection is a regular mongo projection object. Defaults to your default.

upsert(_id: string, val*: object, projection: Projection): Promise<object>

Upserts the passed val. Sets updatedAt & dispatches a updated events if an update occurs. Sets createdAt, updatedAt & dispatches insert events if an insert occurs.

• _id to find
• val to set or insert
• projection is a regular mongo projection object. Defaults to your default.

touch(_id: string, projection: Projection): Promise<object>

Sets updatedAt on the document only. Does not dispatch updated events

• _id to find
• projection is a regular mongo projection object. Defaults to your default.

del(_id: string): Promise<string>

deletes the document specified by the id.

• _id to delete

delUsingFilter({filter: Filter}): Promise<string[]>

deletes all documents matching the mongo filter

• filter is a regular mongo query object