feat: add dynamic schema to postgrest client

Resolves #280

Author: sjones6

src/PostgrestClient.ts

@@ -25,7 +25,7 @@ export default class PostgrestClient<
 > {
   url: string
   headers: Record<string, string>
-  schema?: SchemaName
+  schemaName?: SchemaName
   fetch?: Fetch
 
   // TODO: Add back shouldThrowOnError once we figure out the typings
@@ -52,7 +52,7 @@ export default class PostgrestClient<
   ) {
     this.url = url
     this.headers = { ...DEFAULT_HEADERS, ...headers }
-    this.schema = schema
+    this.schemaName = schema
     this.fetch = fetch
   }
 
@@ -73,7 +73,32 @@ export default class PostgrestClient<
     const url = new URL(`${this.url}/${relation}`)
     return new PostgrestQueryBuilder<Schema, any>(url, {
       headers: { ...this.headers },
-      schema: this.schema,
+      schema: this.schemaName,
+      fetch: this.fetch,
+    })
+  }
+
+  /**
+   * Select a schema to query or perform an function (rpc) call.
+   *
+   * The schema needs to be on the list of exposed schemas inside Supabase.
+   *
+   * @param schema - The schema to query
+   */
+  schema<DynamicSchema extends string & keyof Database>(
+    schema: DynamicSchema
+  ): PostgrestClient<
+    Database,
+    DynamicSchema,
+    Database[DynamicSchema] extends GenericSchema ? Database[DynamicSchema] : any
+  > {
+    return new PostgrestClient<
+      Database,
+      DynamicSchema,
+      Database[DynamicSchema] extends GenericSchema ? Database[DynamicSchema] : any
+    >(this.url, {
+      headers: this.headers,
+      schema,
       fetch: this.fetch,
     })
   }
@@ -143,7 +168,7 @@ export default class PostgrestClient<
       method,
       url,
       headers,
-      schema: this.schema,
+      schema: this.schemaName,
       body,
       fetch: this.fetch,
       allowEmpty: false,

test/basic.ts

@@ -196,6 +196,51 @@ test('switch schema', async () => {
   `)
 })
 
+test('dynamic schema', async () => {
+  const postgrest = new PostgrestClient<Database>(REST_URL)
+  const res = await postgrest.schema('personal').from('users').select()
+  expect(res).toMatchInlineSnapshot(`
+    Object {
+      "count": null,
+      "data": Array [
+        Object {
+          "age_range": "[1,2)",
+          "data": null,
+          "status": "ONLINE",
+          "username": "supabot",
+        },
+        Object {
+          "age_range": "[25,35)",
+          "data": null,
+          "status": "OFFLINE",
+          "username": "kiwicopple",
+        },
+        Object {
+          "age_range": "[25,35)",
+          "data": null,
+          "status": "ONLINE",
+          "username": "awailas",
+        },
+        Object {
+          "age_range": "[20,30)",
+          "data": null,
+          "status": "ONLINE",
+          "username": "dragarcia",
+        },
+        Object {
+          "age_range": "[20,40)",
+          "data": null,
+          "status": "ONLINE",
+          "username": "leroyjenkins",
+        },
+      ],
+      "error": null,
+      "status": 200,
+      "statusText": "OK",
+    }
+  `)
+})
+
 test('on_conflict insert', async () => {
   const res = await postgrest
     .from('users')
@@ -865,6 +910,19 @@ test('rpc with head:true, count:exact', async () => {
   `)
 })
 
+test('rpc with dynamic schema', async () => {
+  const res = await postgrest.schema('personal').rpc('get_status', { name_param: 'kiwicopple' })
+  expect(res).toMatchInlineSnapshot(`
+    Object {
+      "count": null,
+      "data": "OFFLINE",
+      "error": null,
+      "status": 200,
+      "statusText": "OK",
+    }
+  `)
+})
+
 describe("insert, update, delete with count: 'exact'", () => {
   test("insert with count: 'exact'", async () => {
     let res = await postgrest