Adds getOutput method to serverless to return all of the raw entries …

…that match the path (for advanced serverless usage).

Adds `dataFilterSelectors` to configuration file to allow some data to pass through to the JSON object returned by Eleventy.prototype.toJSON. These are lodash selectors.

src/Serverless.js

@@ -155,7 +155,7 @@ class Serverless {
     return {};
   }
 
-  async render() {
+  async getOutput() {
     if (this.dir.startsWith("/var/task/")) {
       process.chdir(this.dir);
     }
@@ -220,27 +220,25 @@ class Serverless {
     // TODO (@zachleat)  https://github.com/11ty/eleventy/issues/1957
     this.deleteEnvironmentVariables();
 
+    return json.filter((entry) => {
+      return entry.inputPath === inputPath;
+    });
+  }
+
+  async render() {
+    let json = await this.getOutput();
+
     if (!json.length) {
       let err = new Error(
-        `Couldn’t find any generated output from Eleventy (URL path parameters: ${JSON.stringify(
+        `Couldn’t find any generated output from Eleventy (Input path: ${inputPath}, URL path parameters: ${JSON.stringify(
           pathParams
         )}).`
       );
       err.httpStatusCode = 404;
       throw err;
     }
 
-    for (let entry of json) {
-      if (entry.inputPath === inputPath) {
-        return entry.content;
-      }
-    }
-
-    // Log to Serverless Function output
-    console.log(json);
-    throw new Error(
-      `Couldn’t find any matching output from Eleventy for ${inputPath} (${json.length} pages rendered).`
-    );
+    return json[0].content;
   }
 }
 

src/Template.js

@@ -3,6 +3,8 @@ const os = require("os");
 const path = require("path");
 const normalize = require("normalize-path");
 const isPlainObject = require("lodash/isPlainObject");
+const lodashGet = require("lodash/get");
+const lodashSet = require("lodash/set");
 const { DateTime } = require("luxon");
 
 const TemplateData = require("./TemplateData");
@@ -805,6 +807,15 @@ class Template extends TemplateContent {
     return content;
   }
 
+  retrieveDataForJsonOutput(data, selectors) {
+    let filtered = {};
+    for (let selector of selectors) {
+      let value = lodashGet(data, selector);
+      lodashSet(filtered, selector, value);
+    }
+    return filtered;
+  }
+
   async generateMapEntry(mapEntry, to) {
     return Promise.all(
       mapEntry._pages.map(async (page) => {
@@ -824,6 +835,16 @@ class Template extends TemplateContent {
             content: content,
           };
 
+          if (
+            this.config.dataFilterSelectors &&
+            this.config.dataFilterSelectors.size > 0
+          ) {
+            obj.data = this.retrieveDataForJsonOutput(
+              page.data,
+              this.config.dataFilterSelectors
+            );
+          }
+
           if (to === "ndjson") {
             let jsonString = JSON.stringify(obj);
             this.logger.toStream(jsonString + os.EOL);

src/UserConfig.js

@@ -77,6 +77,7 @@ class UserConfig {
     this._pluginExecution = false;
 
     this.useTemplateCache = true;
+    this.dataFilterSelectors = new Set();
   }
 
   versionCheck(expected) {
@@ -770,6 +771,7 @@ class UserConfig {
       plugins: this.plugins,
       useTemplateCache: this.useTemplateCache,
       precompiledCollections: this.precompiledCollections,
+      dataFilterSelectors: this.dataFilterSelectors,
     };
   }
 }