feat(db-*): add defaultValues to database schemas (#7368)

## Description

Prior to this change, the `defaultValue` for fields have only been used
in the application layer of Payload. With this change, you get the added
benefit of having the database columns get the default also. This is
especially helpful when adding new columns to postgres with existing
data to avoid needing to write complex migrations. In MongoDB this
change applies the default to the Mongoose model which is useful when
calling payload.db.create() directly.

This only works for statically defined values.

🙏 A big thanks to @r1tsuu for the feature and implementation idea as I
lifted some code from PR #6983

- [x] I have read and understand the
[CONTRIBUTING.md](https://github.com/payloadcms/payload/blob/main/CONTRIBUTING.md)
document in this repository.

## Type of change

- [x] New feature (non-breaking change which adds functionality)
- [x] This change requires a documentation update

## Checklist:

- [x] I have added tests that prove my fix is effective or that my
feature works
- [x] Existing test suite passes locally with my changes
- [x] I have made corresponding changes to the documentation

Author: DanRibbens

docs/fields/overview.mdx

@@ -205,7 +205,9 @@ export const MyField: Field = {
 }
 ```
 
-Default values can be defined as a static string or a function that returns a string. Functions are called with the following arguments:
+Default values can be defined as a static value or a function that returns a value. When a `defaultValue` is defined statically, Payload's DB adapters will apply it to the database schema or models.
+
+Functions can be written to make use of the following argument properties:
 
 - `user` - the authenticated user object
 - `locale` - the currently selected locale string

packages/db-mongodb/src/models/buildSchema.ts

@@ -52,9 +52,19 @@ type FieldSchemaGenerator = (
   buildSchemaOptions: BuildSchemaOptions,
 ) => void
 
+/**
+ * get a field's defaultValue only if defined and not dynamic so that it can be set on the field schema
+ * @param field
+ */
+const formatDefaultValue = (field: FieldAffectingData) =>
+  typeof field.defaultValue !== 'undefined' && typeof field.defaultValue !== 'function'
+    ? field.defaultValue
+    : undefined
+
 const formatBaseSchema = (field: FieldAffectingData, buildSchemaOptions: BuildSchemaOptions) => {
   const { disableUnique, draftsEnabled, indexSortableFields } = buildSchemaOptions
   const schema: SchemaTypeOptions<unknown> = {
+    default: formatDefaultValue(field),
     index: field.index || (!disableUnique && field.unique) || indexSortableFields || false,
     required: false,
     unique: (!disableUnique && field.unique) || false,
@@ -159,7 +169,6 @@ const fieldToSchemaMap: Record<string, FieldSchemaGenerator> = {
           },
         }),
       ],
-      default: undefined,
     }
 
     schema.add({
@@ -174,7 +183,6 @@ const fieldToSchemaMap: Record<string, FieldSchemaGenerator> = {
   ): void => {
     const fieldSchema = {
       type: [new mongoose.Schema({}, { _id: false, discriminatorKey: 'blockType' })],
-      default: undefined,
     }
 
     schema.add({
@@ -339,7 +347,7 @@ const fieldToSchemaMap: Record<string, FieldSchemaGenerator> = {
       },
       coordinates: {
         type: [Number],
-        default: field.defaultValue || undefined,
+        default: formatDefaultValue(field),
         required: false,
       },
     }
@@ -420,7 +428,9 @@ const fieldToSchemaMap: Record<string, FieldSchemaGenerator> = {
 
           return {
             ...locales,
-            [locale]: field.hasMany ? { type: [localeSchema], default: undefined } : localeSchema,
+            [locale]: field.hasMany
+              ? { type: [localeSchema], default: formatDefaultValue(field) }
+              : localeSchema,
           }
         }, {}),
         localized: true,
@@ -440,7 +450,7 @@ const fieldToSchemaMap: Record<string, FieldSchemaGenerator> = {
       if (field.hasMany) {
         schemaToReturn = {
           type: [schemaToReturn],
-          default: undefined,
+          default: formatDefaultValue(field),
         }
       }
     } else {
@@ -453,7 +463,7 @@ const fieldToSchemaMap: Record<string, FieldSchemaGenerator> = {
       if (field.hasMany) {
         schemaToReturn = {
           type: [schemaToReturn],
-          default: undefined,
+          default: formatDefaultValue(field),
         }
       }
     }

packages/db-postgres/src/schema/build.ts

@@ -1,4 +1,3 @@
-/* eslint-disable no-param-reassign */
 import type { Relation } from 'drizzle-orm'
 import type {
   ForeignKeyBuilder,

packages/db-postgres/src/schema/traverseFields.ts

@@ -1,4 +1,3 @@
-/* eslint-disable no-param-reassign */
 import type { Relation } from 'drizzle-orm'
 import type { IndexBuilder, PgColumnBuilder } from 'drizzle-orm/pg-core'
 import type { Field, TabAsField } from 'payload'
@@ -35,6 +34,7 @@ import { buildTable } from './build.js'
 import { createIndex } from './createIndex.js'
 import { idToUUID } from './idToUUID.js'
 import { parentIDColumnMap } from './parentIDColumnMap.js'
+import { withDefault } from './withDefault.js'
 
 type Args = {
   adapter: PostgresAdapter
@@ -170,14 +170,14 @@ export const traverseFields = ({
             )
           }
         } else {
-          targetTable[fieldName] = varchar(columnName)
+          targetTable[fieldName] = withDefault(varchar(columnName), field)
         }
         break
       }
       case 'email':
       case 'code':
       case 'textarea': {
-        targetTable[fieldName] = varchar(columnName)
+        targetTable[fieldName] = withDefault(varchar(columnName), field)
         break
       }
 
@@ -199,23 +199,26 @@ export const traverseFields = ({
             )
           }
         } else {
-          targetTable[fieldName] = numeric(columnName)
+          targetTable[fieldName] = withDefault(numeric(columnName), field)
         }
         break
       }
 
       case 'richText':
       case 'json': {
-        targetTable[fieldName] = jsonb(columnName)
+        targetTable[fieldName] = withDefault(jsonb(columnName), field)
         break
       }
 
       case 'date': {
-        targetTable[fieldName] = timestamp(columnName, {
-          mode: 'string',
-          precision: 3,
-          withTimezone: true,
-        })
+        targetTable[fieldName] = withDefault(
+          timestamp(columnName, {
+            mode: 'string',
+            precision: 3,
+            withTimezone: true,
+          }),
+          field,
+        )
         break
       }
 
@@ -311,13 +314,13 @@ export const traverseFields = ({
             }),
           )
         } else {
-          targetTable[fieldName] = adapter.enums[enumName](fieldName)
+          targetTable[fieldName] = withDefault(adapter.enums[enumName](fieldName), field)
         }
         break
       }
 
       case 'checkbox': {
-        targetTable[fieldName] = boolean(columnName)
+        targetTable[fieldName] = withDefault(boolean(columnName), field)
         break
       }
 

packages/db-postgres/src/schema/withDefault.ts

@@ -0,0 +1,17 @@
+import type { PgColumnBuilder } from 'drizzle-orm/pg-core'
+import type { FieldAffectingData } from 'payload'
+
+export const withDefault = (
+  column: PgColumnBuilder,
+  field: FieldAffectingData,
+): PgColumnBuilder => {
+  if (typeof field.defaultValue === 'undefined' || typeof field.defaultValue === 'function')
+    return column
+
+  if (typeof field.defaultValue === 'string' && field.defaultValue.includes("'")) {
+    const escapedString = field.defaultValue.replaceAll("'", "''")
+    return column.default(escapedString)
+  }
+
+  return column.default(field.defaultValue)
+}

packages/db-sqlite/src/schema/traverseFields.ts

@@ -1,4 +1,3 @@
-/* eslint-disable no-param-reassign */
 import type { Relation } from 'drizzle-orm'
 import type { IndexBuilder, SQLiteColumnBuilder } from 'drizzle-orm/sqlite-core'
 import type { Field, TabAsField } from 'payload'
@@ -30,6 +29,7 @@ import { buildTable } from './build.js'
 import { createIndex } from './createIndex.js'
 import { getIDColumn } from './getIDColumn.js'
 import { idToUUID } from './idToUUID.js'
+import { withDefault } from './withDefault.js'
 
 type Args = {
   adapter: SQLiteAdapter
@@ -166,14 +166,14 @@ export const traverseFields = ({
             )
           }
         } else {
-          targetTable[fieldName] = text(columnName)
+          targetTable[fieldName] = withDefault(text(columnName), field)
         }
         break
       }
       case 'email':
       case 'code':
       case 'textarea': {
-        targetTable[fieldName] = text(columnName)
+        targetTable[fieldName] = withDefault(text(columnName), field)
         break
       }
 
@@ -195,19 +195,19 @@ export const traverseFields = ({
             )
           }
         } else {
-          targetTable[fieldName] = numeric(columnName)
+          targetTable[fieldName] = withDefault(numeric(columnName), field)
         }
         break
       }
 
       case 'richText':
       case 'json': {
-        targetTable[fieldName] = text(columnName, { mode: 'json' })
+        targetTable[fieldName] = withDefault(text(columnName, { mode: 'json' }), field)
         break
       }
 
       case 'date': {
-        targetTable[fieldName] = text(columnName)
+        targetTable[fieldName] = withDefault(text(columnName), field)
         break
       }
 
@@ -295,13 +295,13 @@ export const traverseFields = ({
             }),
           )
         } else {
-          targetTable[fieldName] = text(fieldName, { enum: options })
+          targetTable[fieldName] = withDefault(text(fieldName, { enum: options }), field)
         }
         break
       }
 
       case 'checkbox': {
-        targetTable[fieldName] = integer(columnName, { mode: 'boolean' })
+        targetTable[fieldName] = withDefault(integer(columnName, { mode: 'boolean' }), field)
         break
       }
 

packages/db-sqlite/src/schema/withDefault.ts

@@ -0,0 +1,17 @@
+import type { SQLiteColumnBuilder } from 'drizzle-orm/sqlite-core'
+import type { FieldAffectingData } from 'payload'
+
+export const withDefault = (
+  column: SQLiteColumnBuilder,
+  field: FieldAffectingData,
+): SQLiteColumnBuilder => {
+  if (typeof field.defaultValue === 'undefined' || typeof field.defaultValue === 'function')
+    return column
+
+  if (typeof field.defaultValue === 'string' && field.defaultValue.includes("'")) {
+    const escapedString = field.defaultValue.replaceAll("'", "''")
+    return column.default(escapedString)
+  }
+
+  return column.default(field.defaultValue)
+}

packages/drizzle/src/count.ts

@@ -1,5 +1,4 @@
-import type { Count } from 'payload'
-import type { SanitizedCollectionConfig } from 'payload'
+import type { Count , SanitizedCollectionConfig } from 'payload'
 
 import toSnakeCase from 'to-snake-case'
 
@@ -15,7 +14,7 @@ export const count: Count = async function count(
 
   const tableName = this.tableNameMap.get(toSnakeCase(collectionConfig.slug))
 
-  const db = this.sessions[await req.transactionID]?.db || this.drizzle
+  const db = this.sessions[await req?.transactionID]?.db || this.drizzle
 
   const { joins, where } = await buildQuery({
     adapter: this,

packages/drizzle/src/create.ts

@@ -10,7 +10,7 @@ export const create: Create = async function create(
   this: DrizzleAdapter,
   { collection: collectionSlug, data, req },
 ) {
-  const db = this.sessions[await req.transactionID]?.db || this.drizzle
+  const db = this.sessions[await req?.transactionID]?.db || this.drizzle
   const collection = this.payload.collections[collectionSlug].config
 
   const tableName = this.tableNameMap.get(toSnakeCase(collection.slug))

packages/drizzle/src/createGlobal.ts

@@ -10,7 +10,7 @@ export async function createGlobal<T extends Record<string, unknown>>(
   this: DrizzleAdapter,
   { slug, data, req = {} as PayloadRequest }: CreateGlobalArgs,
 ): Promise<T> {
-  const db = this.sessions[await req.transactionID]?.db || this.drizzle
+  const db = this.sessions[await req?.transactionID]?.db || this.drizzle
   const globalConfig = this.payload.globals.config.find((config) => config.slug === slug)
 
   const tableName = this.tableNameMap.get(toSnakeCase(globalConfig.slug))