Minimal NodeJS/Typescript Implementation of Azure CosmosDB REST API

cosmosdb.ts

const COSMOS_ENDPOINT = 'https://cosmos-demo.documents.azure.com'

async function cosmosFetch(
    method: 'GET' | 'POST' | 'PUT' | 'PATCH',
    path: string,
    headers?: any,
    body?: any
) {
    const dateUtc = new Date().toUTCString()
    const parts = path.match(
        /(.*\/)?(dbs|colls|sprocs|udfs|triggers|users|permissions|docs)(\/.*)?$/
    )
    const resourceType = parts[2]
    const resourceId = parts[3]
        ? (parts[1] || '') + parts[2] + (parts[3] || '')
        : (parts[1] || '').slice(0, -1)
    const stringToSign = `${method.toLowerCase()}\n${resourceType.toLowerCase()}\n${resourceId}\n${dateUtc.toLowerCase()}\n\n`
    const hmac = await crypto.subtle.importKey(
        'raw',
        Buffer.from(process.env.AZURE_COSMOS_KEY, 'base64'),
        { name: 'HMAC', hash: 'SHA-256' },
        false,
        ['sign']
    )
    const signature = await crypto.subtle.sign('HMAC', hmac, new TextEncoder().encode(stringToSign))
    const response = await fetch(`${COSMOS_ENDPOINT}/${path}`, {
        method,
        headers: {
            Authorization: encodeURIComponent(
                `type=master&ver=1.0&sig=${Buffer.from(signature).toString('base64')}`
            ),
            'x-ms-version': '2020-07-15',
            'x-ms-date': dateUtc,
            Accept: 'application/json',
            ...(headers || {}),
        },
        body: JSON.stringify(body),
    })
    let data
    try {
        data = await response.json()
    } catch (err) {}

    if (!response.ok)
        throw new Error(`CosmosDB Error ${response.status}: ${data?.message?.split('\n')[0]}`)
    return data
}

async function main() {
    console.log(await cosmosFetch('GET', 'dbs'))
    console.log(await cosmosFetch('GET', 'dbs/Test'))
    console.log(await cosmosFetch('GET', 'dbs/Test/colls'))
    console.log(await cosmosFetch('GET', 'dbs/Test/colls/test'))
    console.log(await cosmosFetch('GET', 'dbs/Test/colls/test/docs'))
    console.log(
        await cosmosFetch(
            'POST',
            'dbs/Test/colls/test/docs',
            {
                'x-ms-documentdb-isquery': 'True',
                'x-ms-documentdb-query-enablecrosspartition': 'True',
                'Content-Type': 'application/query+json',
            },
            {
                query: 'SELECT c.id FROM c',
            }
        )
    )

    console.log(
        await cosmosFetch('GET', 'dbs/Test/colls/test/docs/wumbology3', {
            'x-ms-documentdb-partitionkey': '["wumbology3"]',
        })
    )

    console.log(
        await cosmosFetch(
            'PATCH',
            'dbs/Test/colls/test/docs/wumbology3',
            {
                'Content-Type': 'application/json',
                'x-ms-documentdb-partitionkey': '["wumbology3"]',
            },
            {
                operations: [
                    {
                        op: 'set',
                        path: '/FamilyName',
                        value: 'Bob',
                    },
                ],
            }
        )
    )

    console.log(await cosmosFetch('GET', 'dbs/Test/colls/test/sprocs'))
    console.log(await cosmosFetch('GET', 'dbs/Test/colls/test/triggers'))

    console.log(
        await cosmosFetch(
            'POST',
            'dbs/Test/colls/test/docs',
            {
                'x-ms-documentdb-isquery': 'True',
                'x-ms-documentdb-query-enablecrosspartition': 'True',
                // 'x-ms-documentdb-populatequerymetrics': 'True',
                'Content-Type': 'application/query+json',
            },
            {
                query: 'SELECT c.id FROM c',
            }
        )
    )

    console.log(await cosmosFetch('GET', 'dbs/Test/users'))
}
main()