(core) move home server into core

Summary: This moves enough server material into core to run a home server.  The data engine is not yet incorporated (though in manual testing it works when ported).

Test Plan: existing tests pass

Reviewers: dsagal

Reviewed By: dsagal

Differential Revision: https://phab.getgrist.com/D2552

app/plugin/FileParserAPI.ts

@@ -0,0 +1,52 @@
+/**
+ * API definitions for FileParser plugins.
+ */
+
+import {GristTables} from './GristTable';
+
+export interface EditOptionsAPI {
+  getParseOptions(parseOptions?: ParseOptions): Promise<ParseOptions>;
+}
+
+export interface ParseFileAPI {
+  parseFile(file: FileSource, parseOptions?: ParseOptions): Promise<ParseFileResult>;
+}
+
+/**
+ * ParseOptions contains parse options depending on plugin,
+ * number of rows, which is special option that can be used for any plugin
+ * and schema for generating parse options UI
+ */
+export interface ParseOptions {
+  NUM_ROWS?: number;
+  SCHEMA?: ParseOptionSchema[];
+}
+
+/**
+ * ParseOptionSchema contains information for generaing parse options UI
+ */
+export interface ParseOptionSchema {
+  name: string;
+  label: string;
+  type: string;
+  visible: boolean;
+}
+
+export interface FileSource {
+  /**
+   * The path is often a temporary file, so its name is meaningless. Access to the file depends on
+   * the type of plugin. For instance, for `safePython` plugins file is directly available at
+   * `/importDir/path`.
+   */
+  path: string;
+
+  /**
+   * Plugins that want to know the original filename should use origName. Depending on the source
+   * of the data, it may or may not be meaningful.
+   */
+  origName: string;
+}
+
+export interface ParseFileResult extends GristTables {
+  parseOptions: ParseOptions;
+}