oops, add missing talerconfig.ts

src/util/talerconfig.ts

@@ -0,0 +1,120 @@
+/*
+ This file is part of GNU Taler
+ (C) 2020 Taler Systems S.A.
+
+ GNU Taler is free software; you can redistribute it and/or modify it under the
+ terms of the GNU General Public License as published by the Free Software
+ Foundation; either version 3, or (at your option) any later version.
+
+ GNU Taler is distributed in the hope that it will be useful, but WITHOUT ANY
+ WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+ A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License along with
+ GNU Taler; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+ */
+
+/**
+ * Utilities to handle Taler-style configuration files.
+ *
+ * @author Florian Dold <dold@taler.net>
+ */
+
+/**
+ * Imports
+ */
+import { AmountJson } from "./amounts";
+import * as Amounts from "./amounts";
+
+export class ConfigError extends Error {
+  constructor(message: string) {
+    super();
+    Object.setPrototypeOf(this, ConfigError.prototype);
+    this.name = "ConfigError";
+    this.message = message;
+  }
+}
+
+type OptionMap = { [optionName: string]: string };
+type SectionMap = { [sectionName: string]: OptionMap };
+
+export class ConfigValue<T> {
+  constructor(
+    private sectionName: string,
+    private optionName: string,
+    private val: string | undefined,
+    private converter: (x: string) => T,
+  ) {}
+
+  required(): T {
+    if (!this.val) {
+      throw new ConfigError(
+        `required option [${this.sectionName}]/${this.optionName} not found`,
+      );
+    }
+    return this.converter(this.val);
+  }
+}
+
+export class Configuration {
+  private sectionMap: SectionMap = {};
+
+  constructor() {}
+
+  loadFromString(s: string): void {
+    const reComment = /^\s*#.*$/;
+    const reSection = /^\s*\[\s*([^\]]*)\s*\]\s*$/;
+    const reParam = /^\s*([^=]+?)\s*=\s*(.*?)\s*$/;
+    const reEmptyLine = /^\s*$/;
+
+    let currentSection: string | undefined = undefined;
+
+    const lines = s.split("\n");
+    for (const line of lines) {
+      console.log("parsing line", JSON.stringify(line));
+      if (reEmptyLine.test(line)) {
+        continue;
+      }
+      if (reComment.test(line)) {
+        continue;
+      }
+      const secMatch = line.match(reSection);
+      if (secMatch) {
+        currentSection = secMatch[1];
+        console.log("setting section to", currentSection);
+        continue;
+      }
+      if (currentSection === undefined) {
+        throw Error("invalid configuration, expected section header");
+      }
+      const paramMatch = line.match(reParam);
+      if (paramMatch) {
+        const optName = paramMatch[1];
+        let val = paramMatch[2];
+        if (val.startsWith('"') && val.endsWith('"')) {
+          val = val.slice(1, val.length - 1);
+        }
+        const sec = this.sectionMap[currentSection] ?? {};
+        this.sectionMap[currentSection] = Object.assign(sec, {
+          [optName]: val,
+        });
+        continue;
+      }
+      throw Error(
+        "invalid configuration, expected section header or option assignment",
+      );
+    }
+
+    console.log("parsed config", JSON.stringify(this.sectionMap, undefined, 2));
+  }
+
+  getString(section: string, option: string): ConfigValue<string> {
+    const val = (this.sectionMap[section] ?? {})[option];
+    return new ConfigValue(section, option, val, x => x);
+  }
+
+  getAmount(section: string, option: string): ConfigValue<AmountJson> {
+    const val = (this.sectionMap[section] ?? {})[option];
+    return new ConfigValue(section, option, val, x => Amounts.parseOrThrow(x));
+  }
+}