Feature: Allow setting backend configuration settings via the UI (#5126)

* Saving some start on this

* At least partially working for the tesseract parser

* Problems with migration testing need to figure out

* Work around that error

* Fixes max m_pixels

* Moving the settings to main paperless application

* Starting some consumer options

* More fixes and work

* Fixes these last tests

* Fix max_length on OcrSettings.mode field

* Fix all fields on Common & Ocr settings serializers

* Umbrellla config view

* Revert "Umbrellla config view"

This reverts commit fbaf9f4be30f89afeb509099180158a3406416a5.

* Updates to use a single configuration object for all settings

* Squashed commit of the following:

commit 8a0a49dd57
Author: shamoon <4887959+shamoon@users.noreply.github.com>
Date:   Tue Dec 19 23:02:47 2023 -0800

    Fix formatting

commit 66b2d90c50
Author: shamoon <4887959+shamoon@users.noreply.github.com>
Date:   Tue Dec 19 22:36:35 2023 -0800

    Refactor frontend data models

commit 5723bd8dd8
Author: Adam Bogdał <adam@bogdal.pl>
Date:   Wed Dec 20 01:17:43 2023 +0100

    Fix: speed up admin panel for installs with a large number of documents (#5052)

commit 9b08ce1761
Author: shamoon <4887959+shamoon@users.noreply.github.com>
Date:   Tue Dec 19 15:18:51 2023 -0800

    Update PULL_REQUEST_TEMPLATE.md

commit a6248bec2d
Author: shamoon <4887959+shamoon@users.noreply.github.com>
Date:   Tue Dec 19 15:02:05 2023 -0800

    Chore: Update Angular to v17 (#4980)

commit b1f6f52486
Author: shamoon <4887959+shamoon@users.noreply.github.com>
Date:   Tue Dec 19 13:53:56 2023 -0800

    Fix: Dont allow null custom_fields property via API (#5063)

commit 638d9970fd
Author: shamoon <4887959+shamoon@users.noreply.github.com>
Date:   Tue Dec 19 13:43:50 2023 -0800

    Enhancement: symmetric document links (#4907)

commit 5e8de4c1da
Author: shamoon <4887959+shamoon@users.noreply.github.com>
Date:   Tue Dec 19 12:45:04 2023 -0800

    Enhancement: shared icon & shared by me filter (#4859)

commit 088bad9030
Author: Trenton H <797416+stumpylog@users.noreply.github.com>
Date:   Tue Dec 19 12:04:03 2023 -0800

    Bulk updates all the backend libraries (#5061)

* Saving some work on frontend config

* Very basic but dynamically-generated config form

* Saving work on slightly less ugly frontend config

* JSON validation for user_args field

* Fully dynamic config form

* Adds in some additional validators for a nicer error message

* Cleaning up the testing and coverage more

* Reverts unintentional change

* Adds documentation about the settings and the precedence

* Couple more commenting and style fixes

---------

Co-authored-by: shamoon <4887959+shamoon@users.noreply.github.com>

src-ui/src/app/services/config.service.spec.ts

@@ -0,0 +1,42 @@
+import { TestBed } from '@angular/core/testing'
+
+import { ConfigService } from './config.service'
+import {
+  HttpClientTestingModule,
+  HttpTestingController,
+} from '@angular/common/http/testing'
+import { environment } from 'src/environments/environment'
+import { OutputTypeConfig, PaperlessConfig } from '../data/paperless-config'
+
+describe('ConfigService', () => {
+  let service: ConfigService
+  let httpTestingController: HttpTestingController
+
+  beforeEach(() => {
+    TestBed.configureTestingModule({
+      imports: [HttpClientTestingModule],
+    })
+    service = TestBed.inject(ConfigService)
+    httpTestingController = TestBed.inject(HttpTestingController)
+  })
+
+  it('should call correct API endpoint on get config', () => {
+    service.getConfig().subscribe()
+    httpTestingController
+      .expectOne(`${environment.apiBaseUrl}config/`)
+      .flush([{}])
+  })
+
+  it('should call correct API endpoint on set config', () => {
+    service
+      .saveConfig({
+        id: 1,
+        output_type: OutputTypeConfig.PDF_A,
+      } as PaperlessConfig)
+      .subscribe()
+    const req = httpTestingController.expectOne(
+      `${environment.apiBaseUrl}config/1/`
+    )
+    expect(req.request.method).toEqual('PATCH')
+  })
+})

src-ui/src/app/services/config.service.ts

@@ -0,0 +1,27 @@
+import { HttpClient } from '@angular/common/http'
+import { Injectable } from '@angular/core'
+import { Observable, first, map } from 'rxjs'
+import { environment } from 'src/environments/environment'
+import { PaperlessConfig } from '../data/paperless-config'
+
+@Injectable({
+  providedIn: 'root',
+})
+export class ConfigService {
+  protected baseUrl: string = environment.apiBaseUrl + 'config/'
+
+  constructor(protected http: HttpClient) {}
+
+  getConfig(): Observable<PaperlessConfig> {
+    return this.http.get<[PaperlessConfig]>(this.baseUrl).pipe(
+      first(),
+      map((configs) => configs[0])
+    )
+  }
+
+  saveConfig(config: PaperlessConfig): Observable<PaperlessConfig> {
+    return this.http
+      .patch<PaperlessConfig>(`${this.baseUrl}${config.id}/`, config)
+      .pipe(first())
+  }
+}