aws-genai-llm-chatbot

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import * as crypto from "@aws-crypto/sha256-js";
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import { defaultProvider } from "@aws-sdk/credential-provider-node";
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import { SignatureV4 } from "@aws-sdk/signature-v4";
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import { HttpRequest } from "@aws-sdk/protocol-http";
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const { Sha256 } = crypto;
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const AWS_REGION = process.env.AWS_REGION || "eu-west-1";
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const endpoint = new URL(process.env.GRAPHQL_ENDPOINT ?? "");
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export const graphQlQuery = async (query: string) => {
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  const signer = new SignatureV4({
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    credentials: defaultProvider(),
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    region: AWS_REGION,
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    service: "appsync",
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    sha256: Sha256,
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  });
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  const requestToBeSigned = new HttpRequest({
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    method: "POST",
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    headers: {
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      "Content-Type": "application/json",
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      host: endpoint.host,
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    },
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    hostname: endpoint.host,
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    body: JSON.stringify({ query }),
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    path: endpoint.pathname,
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  });
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  const signed = await signer.sign(requestToBeSigned);
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  const request = new Request(endpoint, signed);
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  let body;
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  try {
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    const response = await fetch(request);
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    body = await response.json();
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  } catch (error) {
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    throw error;
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  }
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  return body;
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};
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