c12685a518
dependence on dex replaced with ipld-importer subpackage slight improvement to importer tests and formatting gx deps update: new raft, ipld format and ipfs added License: MIT Signed-off-by: Wyatt Daviau <wdaviau@cs.stanford.edu>
10 lines
1.3 KiB
Plaintext
10 lines
1.3 KiB
Plaintext
Package context defines the Context type, which carries deadlines, cancelation signals, and other request-scoped values across API boundaries and between processes.
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Incoming requests to a server should create a Context, and outgoing calls to servers should accept a Context. The chain of function calls between them must propagate the Context, optionally replacing it with a derived Context created using WithCancel, WithDeadline, WithTimeout, or WithValue. When a Context is canceled, all Contexts derived from it are also canceled.
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The WithCancel, WithDeadline, and WithTimeout functions take a Context (the parent) and return a derived Context (the child) and a CancelFunc. Calling the CancelFunc cancels the child and its children, removes the parent's reference to the child, and stops any associated timers. Failing to call the CancelFunc leaks the child and its children until the parent is canceled or the timer fires. The go vet tool checks that CancelFuncs are used on all control-flow paths.
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Programs that use Contexts should follow these rules to keep interfaces consistent across packages and enable static analysis tools to check context propagation:
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Do not store Contexts inside a struct type; instead, pass a Context explicitly to each function that needs it. The Context should be the first parameter, typically named ctx:
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