Better callback as proposed in https://github.com/serverless/examples… #127
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| .catch((error) => { | ||
| callback(error, null); | ||
| }); | ||
| .then(v => callback(null, v), callback); |
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Thanks! I see now what you were referring to. This guarantees that the callback is not called twice even if it throws an error.
Could you explain the change in the commit message instead of referring to a discussion? Then this is good to go.
…error. Previously with the .then(v => callback(null, v)).catch(callback), control goes: 1. work 2. callback 3. work (bad: control should never be passed back to the async function after it calls callback) 4. callback (bad: callbacks should never be executed twice) 5. crash While in this change with .then(v => callback(null, v), callback), control goes: 1. work 2. callback 3. crash In the second case, control flows correctly and the callback is run only once.
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Please refer to #125 (comment)