feat: load metadata from mapped path (#298)

* feat: load metadata from mapped path

* fix: always provide a default in `state.mappedMetadata`

* fix: add surrogate key

* fix: no mapped metadata when target is in code-bus

* fix: getModifiers missing

src/html-pipe.js

@@ -37,6 +37,7 @@ import { PipelineStatusError } from './PipelineStatusError.js';
 import { PipelineResponse } from './PipelineResponse.js';
 import { validatePathInfo } from './utils/path.js';
 import { initAuthRoute } from './utils/auth.js';
+import fetchMappedMetadata from './steps/fetch-mapped-metadata.js';
 
 /**
  * Runs the default pipeline and returns the response.
@@ -88,6 +89,7 @@ export async function htmlPipe(state, req) {
     await Promise.all([
       fetchConfigAll(state, req, res),
       fetchContent(state, req, res),
+      fetchMappedMetadata(state),
     ]);
 
     await requireProject(state, req, res);

src/steps/extract-metadata.js

@@ -158,6 +158,7 @@ export default function extractMetaData(state, req) {
   // with local metadata from document
   const metaConfig = Object.assign(
     state.metadata.getModifiers(state.info.unmappedPath || state.info.path),
+    state.mappedMetadata.getModifiers(state.info.path),
     getLocalMetadata(hast),
   );
 

src/steps/fetch-config-all.js

@@ -35,12 +35,12 @@ async function fetchMetadata(state, req, res) {
     try {
       json = JSON.parse(ret.body);
     } catch (e) {
-      throw new PipelineStatusError(400, `failed parsing of /metadata.json: ${e.message}`);
+      throw new PipelineStatusError(500, `failed parsing of /metadata.json: ${e.message}`);
     }
 
     const { data } = json.default ?? json;
     if (!Array.isArray(data)) {
-      throw new PipelineStatusError(400, 'failed loading of /metadata.json: data must be an array');
+      throw new PipelineStatusError(500, 'failed loading of /metadata.json: data must be an array');
     }
 
     state.metadata = Modifiers.fromModifierSheet(

src/steps/fetch-mapped-metadata.js

@@ -0,0 +1,55 @@
+/*
+ * Copyright 2021 Adobe. All rights reserved.
+ * This file is licensed to you under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License. You may obtain a copy
+ * of the License at http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under
+ * the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR REPRESENTATIONS
+ * OF ANY KIND, either express or implied. See the License for the specific language
+ * governing permissions and limitations under the License.
+ */
+
+import { PipelineStatusError } from '../PipelineStatusError.js';
+import { Modifiers } from '../utils/modifiers.js';
+
+/**
+ * Loads metadata for a mapped path and puts it into `state.mappedMetadata`. If path is not
+ * mapped or there is no `metadata.json` at that path, puts an `EMPTY` Modifiers object into
+ * `state.mappedMetadata`.
+ *
+ * @type PipelineStep
+ * @param {PipelineState} state
+ * @returns {Promise<void>}
+ */
+export default async function fetchMappedMetadata(state) {
+  state.mappedMetadata = Modifiers.EMPTY;
+  if (!state.mapped) {
+    return;
+  }
+  const { contentBusId, partition } = state;
+  const metadataPath = `${state.info.path}/metadata.json`;
+  const key = `${contentBusId}/${partition}${metadataPath}`;
+  const ret = await state.s3Loader.getObject('helix-content-bus', key);
+  if (ret.status === 200) {
+    let json;
+    try {
+      json = JSON.parse(ret.body);
+    } catch (e) {
+      throw new PipelineStatusError(500, `failed parsing of ${metadataPath}: ${e.message}`);
+    }
+
+    const { data } = json.default ?? json;
+    if (!Array.isArray(data)) {
+      throw new PipelineStatusError(500, `failed loading of ${metadataPath}: data must be an array`);
+    }
+
+    state.mappedMetadata = Modifiers.fromModifierSheet(
+      data,
+    );
+    return;
+  }
+  if (ret.status !== 404) {
+    throw new PipelineStatusError(502, `failed to load ${metadataPath}: ${ret.status}`);
+  }
+}

src/steps/folder-mapping.js

@@ -55,6 +55,7 @@ export default function folderMapping(state) {
       state.info.resourcePath = mapped;
       state.log.info(`mapped ${path} to ${state.info.resourcePath} (code-bus)`);
     } else {
+      state.mapped = true;
       state.log.info(`mapped ${path} to ${state.info.path} (content-bus)`);
     }
   }

src/steps/set-x-surrogate-key-header.js

@@ -37,10 +37,15 @@ export default async function setXSurrogateKeyHeader(state, req, res) {
   } else if (path.endsWith('.plain.html')) {
     path = path.substring(0, path.length - '.plain.html'.length);
   }
-  keys.push(await computeSurrogateKey(`${contentBusId}${path}`));
+  const hash = await computeSurrogateKey(`${contentBusId}${path}`);
+  keys.push(hash);
 
   keys.push(`${contentBusId}_metadata`);
   keys.push(`${ref}--${repo}--${owner}_head`);
 
+  if (state.mapped) {
+    keys.push(`${hash}_metadata`);
+  }
+
   res.headers.set('x-surrogate-key', keys.join(' '));
 }

test/steps/fetch-config-all.test.js

@@ -210,7 +210,7 @@ describe('Fetch Metadata fallback', () => {
           headers: new Map(),
         }),
     });
-    await assert.rejects(promise, new PipelineStatusError(400, 'failed parsing of /metadata.json: Unexpected token h in JSON at position 1'));
+    await assert.rejects(promise, new PipelineStatusError(500, 'failed parsing of /metadata.json: Unexpected token h in JSON at position 1'));
   });
 
   it('throws error on metadata with no data array', async () => {
@@ -225,7 +225,7 @@ describe('Fetch Metadata fallback', () => {
           headers: new Map(),
         }),
     });
-    await assert.rejects(promise, new PipelineStatusError(400, 'failed loading of /metadata.json: data must be an array'));
+    await assert.rejects(promise, new PipelineStatusError(500, 'failed loading of /metadata.json: data must be an array'));
   });
 
   it('throws error on generic error', async () => {

test/steps/fetch-mapped-metadata.test.js

@@ -0,0 +1,75 @@
+/*
+ * Copyright 2018 Adobe. All rights reserved.
+ * This file is licensed to you under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License. You may obtain a copy
+ * of the License at http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under
+ * the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR REPRESENTATIONS
+ * OF ANY KIND, either express or implied. See the License for the specific language
+ * governing permissions and limitations under the License.
+ */
+/* eslint-env mocha */
+import assert from 'assert';
+import { PipelineStatusError } from '../../src/index.js';
+import { StaticS3Loader } from '../StaticS3Loader.js';
+import fetchMappedMetadata from '../../src/steps/fetch-mapped-metadata.js';
+
+describe('Fetch Mapped Metadata', () => {
+  it('throws error on invalid json', async () => {
+    const promise = fetchMappedMetadata({
+      log: console,
+      contentBusId: 'foo-id',
+      partition: 'live',
+      mapped: true,
+      info: {
+        path: '/mapped',
+      },
+      s3Loader: new StaticS3Loader()
+        .reply('helix-content-bus', 'foo-id/live/mapped/metadata.json', {
+          status: 200,
+          body: 'this is no json!',
+          headers: new Map(),
+        }),
+    });
+    await assert.rejects(promise, new PipelineStatusError(500, 'failed parsing of /mapped/metadata.json: Unexpected token h in JSON at position 1'));
+  });
+
+  it('throws error on metadata with no data array', async () => {
+    const promise = fetchMappedMetadata({
+      log: console,
+      contentBusId: 'foo-id',
+      partition: 'live',
+      mapped: true,
+      info: {
+        path: '/mapped',
+      },
+      s3Loader: new StaticS3Loader()
+        .reply('helix-content-bus', 'foo-id/live/mapped/metadata.json', {
+          status: 200,
+          body: '{}',
+          headers: new Map(),
+        }),
+    });
+    await assert.rejects(promise, new PipelineStatusError(500, 'failed loading of /mapped/metadata.json: data must be an array'));
+  });
+
+  it('throws error on generic error', async () => {
+    const promise = fetchMappedMetadata({
+      log: console,
+      contentBusId: 'foo-id',
+      partition: 'live',
+      mapped: true,
+      info: {
+        path: '/mapped',
+      },
+      s3Loader: new StaticS3Loader()
+        .reply('helix-content-bus', 'foo-id/live/mapped/metadata.json', {
+          status: 500,
+          body: '',
+          headers: new Map(),
+        }),
+    });
+    await assert.rejects(promise, new PipelineStatusError(502, 'failed to load /mapped/metadata.json: 500'));
+  });
+});