Created the type graph

server/simpleQL/index.js

@@ -0,0 +1,104 @@
+//the main function to be returned
+const main = (schema, handler) => {
+	const typeGraph = buildTypeGraph(schema);
+
+	console.log(typeGraph);
+
+	//the receiving function - this will be called multiple times
+	return reqBody => {
+		return '';
+	};
+};
+
+//parse the schema into a type graph
+const buildTypeGraph = schema => {
+	//the default graph
+	let graph = {
+		String: { scalar: true },
+		Integer: { scalar: true },
+		Float: { scalar: true },
+		Boolean: { scalar: true },
+	};
+
+	//parse the schema
+	const tokens = schema.split(/(\s+)/).filter(s => s.trim().length > 0);
+	let pos = 0;
+
+	while (tokens[pos]) {
+		//check for keywords
+		switch(tokens[pos++]) {
+			case 'type':
+				graph[tokens[pos]] = parseCompoundType(tokens, pos);
+
+				//advance to the end of the compound type
+				while(tokens[pos] && tokens[pos++] != '}');
+
+				break;
+
+			case 'scalar':
+				graph[tokens[pos++]] = { scalar: true };
+				break;
+
+			default:
+				throw 'Unknown token ' + tokens[pos -1];
+		}
+	}
+
+	return graph;
+};
+
+const parseCompoundType = (tokens, pos) => {
+	pos++; //eat the compound name
+
+	//format check (not strictly necessary, but it looks nice)
+	if (tokens[pos++] != '{') {
+		throw 'Expected \'{\' in compound type definition';
+	}
+
+	//graph component to be returned
+	const compound = {};
+
+	//for each line of the compound type
+	while (tokens[pos] && tokens[pos] != '}') {
+		let type = tokens[pos++];
+		const name = tokens[pos++];
+
+		//parse the extra typing data
+		let array = false;
+		let nullable = true;
+
+		//not nullable
+		if (type[0] === '!') {
+			nullable = false;
+			type = type.slice(1);
+		}
+
+		//is array
+		if (type.endsWith('[]')) {
+			array = true;
+			type = type.slice(0, type.length - 2);
+		}
+
+		//no mangled types or names
+		checkAlphaNumeric(type);
+		checkAlphaNumeric(name);
+
+		//finally, push to the compound definition
+		compound[name] = {
+			typeName: type,
+			array: array,
+			nullable: nullable,
+		};
+	}
+
+	return compound;
+}
+
+const checkAlphaNumeric = (str) => {
+	if (!/^[a-z0-9]+$/i.test(str)) {
+		throw 'Unexpected string ' + str;
+	}
+};
+
+//return
+module.exports = main;