refactor: basic support for versioned functions

lib/domain/Functions.js

@@ -0,0 +1,235 @@
+const crypto = require('crypto');
+const semver = require('semver');
+
+const log = require('../support/log');
+const { StdoutLogStorage, DefaultLogStorage } = require('./LogStorage');
+
+const Metric = require('./Metric');
+
+const Pipeline = require('./Pipeline');
+const ErrorTracker = require('./ErrorTracker');
+
+function codeFileName(namespace, codeId, version) {
+  if (version === undefined || version === 'latest') {
+    return `${namespace}/${codeId}.js`;
+  }
+  return `${namespace}/${codeId}/${version}.js`;
+}
+
+class Functions {
+  constructor(storage, sandbox, req) {
+    this.storage = storage;
+    this.sandbox = sandbox;
+    this.req = req;
+  }
+
+  async updateVersion(namespace, id, version) {
+    if (!version) {
+      return;
+    }
+
+    // Latest versions are saved to namespace
+    let latest = {};
+    const ns = await this.storage.getNamespace(namespace) || { namespace };
+
+    if (ns.latest) {
+      latest = ns.latest;
+    }
+
+    if (Object.prototype.hasOwnProperty.call(latest, id)) {
+      const curVersion = latest[id];
+      if (semver.gt(version, curVersion)) {
+        latest[id] = version;
+      }
+    } else {
+      latest[id] = version;
+    }
+
+    ns.latest = latest;
+    await this.storage.putNamespace(namespace, ns);
+  }
+
+  async create(namespace, id, version, code, env) {
+    let v = version;
+    const filename = codeFileName(namespace, id, version);
+
+    if (version === 'latest') {
+      v = null;
+    }
+
+    const invalid = this.sandbox.testSyntaxError(filename, code, {
+      console: new StdoutLogStorage(namespace, id, v).console,
+    });
+    if (invalid) {
+      this.req.log.error(`Failed to post code: ${invalid.error}`);
+      return {
+        status: 400,
+        body: invalid,
+      };
+    }
+
+    const hash = crypto.createHash('sha1').update(code).digest('hex');
+    const data = { id, version, code, hash };
+
+    if (env) {
+      data.env = env;
+    }
+
+    try {
+      await this.storage.putCode(namespace, id, v, data);
+
+      await this.updateVersion(namespace, id, v);
+
+      return {
+        status: 200,
+        body: data,
+      };
+    } catch (err) {
+      log.error(`[${namespace}:${id}:${version}] ${err}`);
+      return {
+        status: 500,
+        body: { error: err.message },
+      };
+    }
+  }
+
+  async run(namespace, id, version) {
+    let v = version;
+    const filename = codeFileName(namespace, id, version);
+    const metric = new Metric('function-run');
+
+    const ns = await this.storage.getNamespace(namespace);
+    if (!ns) {
+      v = null;
+    } else if (ns.latest && version === 'latest') {
+      v = ns.latest[id];
+    }
+
+    const logStorage = new DefaultLogStorage(namespace, id, v, this.req);
+
+    let code;
+    try {
+      code = await this.storage.getCodeByCache(namespace, id, v, {
+        preCache: (preCode) => {
+          preCode.script = this.sandbox.compileCode(filename, preCode.code);
+          return preCode;
+        },
+      });
+
+      if (!code) {
+        const errMsg = v ? `Code '${namespace}/${id}/${v}' was not found` : `Code '${namespace}/${id}' was not found`;
+        return {
+          status: 404,
+          body: { error: errMsg },
+        };
+      }
+    } catch (err) {
+      return {
+        status: err.statusCode || 500,
+        body: { error: err.message },
+      };
+    }
+
+    try {
+      const options = {
+        console: logStorage.console,
+        env: code.env,
+      };
+      const result = await this.sandbox.runScript(code.script, this.req, options);
+
+      const spent = metric.observeFunctionRun({ namespace, id, version, status: result.status });
+      logStorage.flush({
+        status: result.status,
+        requestTime: spent,
+      });
+      return result;
+    } catch (err) {
+      logStorage.console.error(`Failed to run function: ${err}`);
+      logStorage.console.error(err.stack);
+      const status = err.statusCode || 500;
+      const errResult = {
+        status,
+        body: { error: err.message },
+      };
+
+      const spent = metric.observeFunctionRun({ namespace, id, version, status });
+
+      const logResult = logStorage.flush({
+        status,
+        requestTime: spent,
+      });
+
+      const { sentryDSN } = code;
+
+      const extra = Object.assign({ body: this.req.body }, logResult || {});
+      const errTracker = new ErrorTracker({
+        sentryDSN,
+        filename,
+        extra,
+        tags: { codeHash: code.hash },
+        code: code.code,
+      });
+      errTracker.notify(err);
+      return errResult;
+    }
+  }
+
+  async runPipeline(stepsInput) {
+    const metric = new Metric('pipeline-run');
+
+    const stepsPromises = stepsInput.map(async (step) => {
+      const [namespace, id, version] = step.split('/', 3);
+      const ns = await this.storage.getNamespace(namespace);
+
+      // Return versioned function
+      if (version !== undefined || version !== 'latest') {
+        return { namespace, id, version };
+      }
+
+      // Handle latest and unversioned functions
+      let v = version;
+      if (!ns) {
+        v = null;
+      } else if (ns.latest && version === 'latest') {
+        v = ns.latest[id];
+      }
+      return { namespace, id, version: v };
+    });
+
+    const steps = await Promise.all(stepsPromises);
+
+    try {
+      const codes = await this.storage.getCodesByCache(steps, {
+        preCache: (code) => {
+          const filename = codeFileName(code.namespace, code.id, code.version);
+          code.script = this.sandbox.compileCode(filename, code.code);
+          return code;
+        },
+      });
+
+      for (let i = 0; i < codes.length; i += 1) {
+        if (!codes[i]) {
+          const { namespace, id, version } = steps[i];
+          const codeName = version ? `${namespace}/${id}/${version}` : `${namespace}/${id}`;
+          const e = new Error(`Code '${codeName}' was not found`);
+          e.statusCode = 404;
+          throw e;
+        }
+      }
+
+      const result = await new Pipeline(this.sandbox, this.req, codes).run();
+      metric.observePipelineRun(result.status);
+      return result;
+    } catch (err) {
+      const result = {
+        status: err.statusCode || 500,
+        body: { error: err.message },
+      };
+
+      metric.observePipelineRun(result.status);
+      return result;
+    }
+  }
+}
+
+module.exports = Functions;

lib/domain/LogStorage.js

@@ -19,18 +19,18 @@ function extractHTTPFields(req) {
 
 class StdoutLogStorage {
   /* eslint class-methods-use-this: ["error", { "exceptMethods": ["flush"] }] */
-  constructor(namespace, id) {
-    this.console = new PrefixLog(`namespace:${namespace}, id:${id}`);
+  constructor(namespace, id, version) {
+    this.console = new PrefixLog(`namespace:${namespace}, id:${id}, version:${version}`);
   }
 
   flush() {}
 }
 
 class GelfLogStorage {
-  constructor(namespace, id, req) {
+  constructor(namespace, id, version, req) {
     this.stream = new MemoryStream(config.log.maxFullMessage);
     this.console = new PrefixLog(null, this.stream, this.stream);
-    this.file = `${namespace}/${id}.js`;
+    this.file = `${namespace}/${id}/${version}.js`;
     this.namespace = namespace;
     this.fields = extractHTTPFields(req);
     this.gelfClients = GelfLogStorage.prepareGelfClients();

lib/domain/Metric.js

@@ -24,7 +24,7 @@ const functionRunHistogram = new prometheusClient.Histogram({
   name: 'backstage_functions_function_run_duration_seconds',
   help: 'How many time spent to run a function in seconds',
   buckets,
-  labelNames: ['namespace', 'id'],
+  labelNames: ['namespace', 'id', 'version'],
 });
 
 const functionOverviewRunHistogram = new prometheusClient.Histogram({
@@ -61,7 +61,7 @@ const functionOverviewRunCounter = new prometheusClient.Counter({
 const functionRunCounter = new prometheusClient.Counter({
   name: 'backstage_functions_function_run_total',
   help: 'What is the status code of a function',
-  labelNames: ['namespace', 'id', 'status'],
+  labelNames: ['namespace', 'id', 'version', 'status'],
 });
 
 const functionPipelineCounter = new prometheusClient.Counter({
@@ -81,15 +81,15 @@ class Metric {
     this.start = Date.now();
   }
 
-  observeFunctionRun({ namespace, id, status }) {
+  observeFunctionRun({ namespace, id, version, status }) {
     const spent = (Date.now() - this.start) / 1000;
     const normalizedStatusCode = normalizeStatusCode(status);
 
     functionOverviewRunHistogram.observe(spent);
     functionOverviewRunCounter.labels(normalizedStatusCode).inc();
 
-    functionRunHistogram.labels(namespace, id).observe(spent);
-    functionRunCounter.labels(namespace, id, normalizedStatusCode).inc();
+    functionRunHistogram.labels(namespace, id, version).observe(spent);
+    functionRunCounter.labels(namespace, id, version, normalizedStatusCode).inc();
 
     return spent;
   }

lib/domain/Pipeline.js

@@ -4,8 +4,8 @@ const Metric = require('./Metric');
 const { DefaultLogStorage } = require('./LogStorage');
 const ErrorTracker = require('./ErrorTracker');
 
-function codeFileName(namespace, codeId) {
-  return `${namespace}/${codeId}.js`;
+function codeFileName(namespace, codeId, version) {
+  return `${namespace}/${codeId}/${version}.js`;
 }
 
 class Pipeline {
@@ -25,8 +25,8 @@ class Pipeline {
     this.steps = nextSteps;
 
     const metric = new Metric('function-run');
-    const filename = codeFileName(step.namespace, step.id);
-    const logStorage = new DefaultLogStorage(step.namespace, step.id, this.req);
+    const filename = codeFileName(step.namespace, step.id, step.version);
+    const logStorage = new DefaultLogStorage(step.namespace, step.id, step.version, this.req);
 
     const options = {
       console: logStorage.console,
@@ -38,6 +38,7 @@ class Pipeline {
       const spent = metric.observeFunctionRun({
         namespace: step.namespace,
         id: step.id,
+        version: step.version,
         status: result.status,
       });
 
@@ -59,6 +60,7 @@ class Pipeline {
       } else {
         result.body.namespace = step.namespace;
         result.body.functionId = step.id;
+        result.body.version = step.version;
 
         return result;
       }
@@ -74,6 +76,7 @@ class Pipeline {
       const spent = metric.observeFunctionRun({
         namespace: step.namespace,
         id: step.id,
+        version: step.version,
         status,
       });