added fetching to addStyle() function and parsed it into serve_style and serve_rendered

src/serve_rendered.js

@@ -1028,10 +1028,11 @@ export const serve_rendered = {
    * @param {object} params Parameters object.
    * @param {string} id ID of the item.
    * @param {object} programOpts - An object containing the program options
+   * @param {object} style pre-fetched/read StyleJSON object.
    * @param {Function} dataResolver Function to resolve data.
    * @returns {Promise<void>}
    */
-  add: async function (options, repo, params, id, programOpts, dataResolver) {
+  add: async function (options, repo, params, id, programOpts, style, dataResolver) {
     const map = {
       renderers: [],
       renderersStatic: [],
@@ -1041,7 +1042,7 @@ export const serve_rendered = {
 
     const { publicUrl, verbose } = programOpts;
 
-    let styleJSON;
+    const styleJSON = clone(style);
     /**
      * Creates a pool of renderers.
      * @param {number} ratio Pixel ratio
@@ -1230,12 +1231,6 @@ export const serve_rendered = {
 
     const styleFile = params.style;
     const styleJSONPath = path.resolve(options.paths.styles, styleFile);
-    try {
-      styleJSON = JSON.parse(await fsp.readFile(styleJSONPath));
-    } catch (e) {
-      console.log('Error parsing style file');
-      return false;
-    }
 
     if (styleJSON.sprite) {
       if (!Array.isArray(styleJSON.sprite)) {

src/serve_style.js

@@ -12,6 +12,7 @@ import {
   allowedSpriteFormats,
   fixUrl,
   readFile,
+  isValidHttpUrl,
 } from './utils.js';
 
 const httpTester = /^https?:\/\//i;
@@ -196,6 +197,7 @@ export const serve_style = {
    * @param {object} params Parameters object containing style path
    * @param {string} id ID of the style.
    * @param {object} programOpts - An object containing the program options
+   * @param {object} style pre-fetched/read StyleJSON object.
    * @param {Function} reportTiles Function for reporting tile sources.
    * @param {Function} reportFont Function for reporting font usage
    * @returns {Promise<boolean>} true if add is successful
@@ -206,27 +208,13 @@ export const serve_style = {
     params,
     id,
     programOpts,
+    style,
     reportTiles,
     reportFont,
   ) {
     const { publicUrl } = programOpts;
-    const styleFile = path.resolve(options.paths.styles, params.style);
-
-    let styleFileData;
-    try {
-      styleFileData = await fs.promises.readFile(styleFile);
-    } catch (e) {
-      console.log(`Error reading style file "${params.style}"`);
-      return false;
-    }
-
-    let styleJSON;
-    try {
-      styleJSON = JSON.parse(styleFileData);
-    } catch (e) {
-      console.log(`Error parsing style JSON from "${params.style}"`);
-      return false;
-    }
+    const styleFile = path.resolve(options.paths.styles, params.style)
+    const styleJSON = clone(style);
 
     const validationErrors = validateStyleMin(styleJSON);
     if (validationErrors.length > 0) {

src/server.js

@@ -182,6 +182,26 @@ async function start(opts) {
    */
   async function addStyle(id, item, allowMoreData, reportFonts) {
     let success = true;
+
+    let styleJSON;
+    try {
+      if (isValidHttpUrl(item.style)){
+        const res = await fetch(item.style);
+        if (!res.ok) {
+          throw new Error(`fetch error ${res.status}`);
+        }
+        styleJSON = await res.json();
+
+      } else {
+        const styleFile = path.resolve(options.paths.styles, item.style);
+        const styleFileData = await fs.promises.readFile(styleFile);
+        styleJSON = JSON.parse(styleFileData);
+      }
+    } catch (e) {
+      console.log(`Error getting style file "${item.style}"`);
+      return false;
+    }
+
     if (item.serve_data !== false) {
       success = await serve_style.add(
         options,
@@ -189,6 +209,7 @@ async function start(opts) {
         item,
         id,
         opts,
+        styleJSON,
         (styleSourceId, protocol) => {
           let dataItemId;
           for (const id of Object.keys(data)) {
@@ -246,6 +267,7 @@ async function start(opts) {
             item,
             id,
             opts,
+            styleJSON,
             function dataResolver(styleSourceId) {
               let fileType;
               let inputFile;