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Trying to trigger AppSync query via lambda function. V4 signer.addauthorization not working. Error message: "Data must be a string or a buffer"

See original GitHub issue

Error Message 2018-11-23T14:37:03.533Z 3e0ff525-ef2d-11e8-8328-89b33f69a07f TypeError: Data must be a string or a buffer at Hmac.update (crypto.js:99:16) at Object.hmac (/var/task/node_modules/aws-sdk/lib/util.js:399:50) at Object.getSigningKey (/var/task/node_modules/aws-sdk/lib/signers/v4_credentials.js:74:35) at V4.signature (/var/task/node_modules/aws-sdk/lib/signers/v4.js:98:36) at V4.authorization (/var/task/node_modules/aws-sdk/lib/signers/v4.js:93:36) at V4.addAuthorization (/var/task/node_modules/aws-sdk/lib/signers/v4.js:35:12) at AWS.config.credentials.get.err (/var/task/index.js:52:10) at Credentials.get (/var/task/node_modules/aws-sdk/lib/credentials.js:126:7) at exports.handler (/var/task/index.js:42:25) END RequestId: 3e0ff525-ef2d-11e8-8328-89b33f69a07f REPORT RequestId: 3e0ff525-ef2d-11e8-8328-89b33f69a07f Duration: 103.19 ms Billed Duration: 200 ms Memory Size: 128 MB Max Memory Used: 60 MB RequestId: 3e0ff525-ef2d-11e8-8328-89b33f69a07f Process exited before completing request

Expected result The V4 signing should complete successfully.

Current result it currently fails with the error message above. I did some digging, in the hmac function in util.js, and realized that it gets called 3 times while the lambda function runs. I only call signer.addAuthorization(cred, date) once.

the first 2 times hmac gets called, it has a correct string parameter, which allows the successful creation of a buffer used in the function to create a new hmac, and return it.

the third time, this string parameter is false. Thus, the Buffer isn’t created, and the hmac.update(string) function fails with the error indicated above.

any help? Could this be a result of something I’m doing wrong?

Issue Analytics

State:
Created 5 years ago
Reactions:3
Comments:11 (3 by maintainers)

Top GitHub Comments

2reactions

nireakcommented, Mar 10, 2019

In case it helps somebody…I had the same problem and the origin of it was that the region environment variable was empty ( I was typing env.REGION when mine was defined in lowercase: env.region)

1reaction

hagiosoforicommented, Nov 26, 2018

lambda runtime Node 8.10

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