diff --git a/api/graphql.js b/api/graphql.js index 8e694c6..1a08d41 100644 --- a/api/graphql.js +++ b/api/graphql.js @@ -5,14 +5,48 @@ const beeline = require("honeycomb-beeline")({ ? "Dress to Impress (2020)" : "Dress to Impress (2020, dev)", serviceName: "impress-2020-gql-server", + samplerHook, }); const { ApolloServer } = require("../src/server/lib/apollo-server-vercel"); const { config } = require("../src/server"); +const crypto = require("crypto"); const server = new ApolloServer(config); const serverHandler = server.createHandler(); +// We apply different sampling rates for different GraphQL operations +// (according to the client-defined query name), depending on how much load +// we're getting on them. For most operations, we just save all the events, but +// especially heavy-load operations get a lower sampling rate! +const OPERATION_SAMPLE_RATES = { + ApiOutfitImage: 10, // save 1 out of every 10, ignore the others + SearchPanel: 5, // save 1 out of every 5, ignore the others +}; +function samplerHook(data) { + // Use the sample rate from the table above. + // Defaults to 1 (all) for most operations. + let sampleRate = OPERATION_SAMPLE_RATES[data["app.operation_name"]] || 1; + + // Use the `deterministicSampler` to decide whether this event should be + // sampled. This might be a child event of a higher-level trace, and we want + // to make sure that we always return all child events of traces we've + // sampled, and no child events of traces we haven't. Deterministically + // sampling by trace ID does this for us! + // + // This strategy is outlined in: https://docs.honeycomb.io/getting-data-in/javascript/beeline-nodejs/#sampling-events. + const shouldSample = deterministicSampler(data["trace.trace_id"], sampleRate); + + return { shouldSample, sampleRate }; +} +function deterministicSampler(traceId, sampleRate) { + // Copied from https://docs.honeycomb.io/getting-data-in/javascript/beeline-nodejs/#sampling-events + const MAX_UINT32 = Math.pow(2, 32) - 1; + const sum = crypto.createHash("sha1").update(traceId).digest(); + const upperBound = (MAX_UINT32 / sampleRate) >>> 0; + return sum.readUInt32BE(0) <= upperBound; +} + async function handle(req, res) { await serverHandler(req, res); diff --git a/api/outfitImage.js b/api/outfitImage.js index 3ebfc55..a968029 100644 --- a/api/outfitImage.js +++ b/api/outfitImage.js @@ -29,6 +29,7 @@ const beeline = require("honeycomb-beeline")({ ? "Dress to Impress (2020)" : "Dress to Impress (2020, dev)", serviceName: "impress-2020-gql-server", + sampleRate: 10, }); import fetch from "node-fetch"; diff --git a/src/server/lib/beeline-graphql.js b/src/server/lib/beeline-graphql.js index 474669b..e8b887a 100644 --- a/src/server/lib/beeline-graphql.js +++ b/src/server/lib/beeline-graphql.js @@ -9,6 +9,9 @@ const beelinePlugin = { name: operationName, operation_name: operationName, }); + beeline.addTraceContext({ + operation_name: operationName, + }); }, willSendResponse() { beeline.finishTrace(trace);