@aws-lambda-powertools/parser/lib/esm/envelopes/cloudwatch.js

The parser package for the Powertools for AWS Lambda (TypeScript) library.

import { ZodError } from 'zod';
import { ParseError } from '../errors.js';
import { CloudWatchLogsSchema } from '../schemas/index.js';
import { envelopeDiscriminator } from './envelope.js';
/**
 * CloudWatch Envelope to extract messages from the `awslogs.data.logEvents` key.
 */
export const CloudWatchEnvelope = {
    /**
     * This is a discriminator to differentiate whether an envelope returns an array or an object
     * @hidden
     */
    [envelopeDiscriminator]: 'array',
    parse(data, schema) {
        const parsedEnvelope = CloudWatchLogsSchema.parse(data);
        return parsedEnvelope.awslogs.data.logEvents.map((record, index) => {
            try {
                return schema.parse(record.message);
            }
            catch (error) {
                throw new ParseError(`Failed to parse CloudWatch log event at index ${index}`, {
                    cause: new ZodError(error.issues.map((issue) => ({
                        ...issue,
                        path: [
                            'awslogs',
                            'data',
                            'logEvents',
                            index,
                            'message',
                            ...issue.path,
                        ],
                    }))),
                });
            }
        });
    },
    safeParse(data, schema) {
        const parsedEnvelope = CloudWatchLogsSchema.safeParse(data);
        if (!parsedEnvelope.success) {
            return {
                success: false,
                error: new ParseError('Failed to parse CloudWatch Log envelope', {
                    cause: parsedEnvelope.error,
                }),
                originalEvent: data,
            };
        }
        const result = parsedEnvelope.data.awslogs.data.logEvents.reduce((acc, record, index) => {
            const result = schema.safeParse(record.message);
            if (!result.success) {
                const issues = result.error.issues.map((issue) => ({
                    ...issue,
                    path: [
                        'awslogs',
                        'data',
                        'logEvents',
                        index,
                        'message',
                        ...issue.path,
                    ],
                }));
                acc.success = false;
                acc.errors[index] = { issues };
                return acc;
            }
            acc.messages.push(result.data);
            return acc;
        }, {
            success: true,
            messages: [],
            errors: {},
        });
        if (result.success) {
            return { success: true, data: result.messages };
        }
        const errorMessage = Object.keys(result.errors).length > 1
            ? `Failed to parse CloudWatch Log messages at indexes ${Object.keys(result.errors).join(', ')}`
            : `Failed to parse CloudWatch Log message at index ${Object.keys(result.errors)[0]}`;
        const errorCause = new ZodError(Object.values(result.errors).flatMap((error) => error.issues));
        return {
            success: false,
            error: new ParseError(errorMessage, { cause: errorCause }),
            originalEvent: data,
        };
    },
};