@graphprotocol/client-polling-live
Version:
82 lines (81 loc) • 3.53 kB
JavaScript
import { isAsyncIterable } from '@envelop/core';
import { GraphQLError, Kind, visit } from 'graphql';
import { Repeater } from '@repeaterjs/repeater';
import { mergeSchemas } from '@graphql-tools/schema';
export default function usePollingLive({ config: { defaultInterval = 1000 } = {} } = {}) {
return {
onSchemaChange({ schema, replaceSchema }) {
if (!schema.getDirective('live')) {
replaceSchema(mergeSchemas({
schemas: [schema],
typeDefs: /* GraphQL */ `
directive @live(interval: Int) on QUERY
`,
}));
}
},
onExecute({ args, executeFn, setExecuteFn }) {
var _a, _b;
let liveDirectiveNode;
args.document = visit(args.document, {
OperationDefinition(node) {
var _a;
if (args.operationName != null && ((_a = node.name) === null || _a === void 0 ? void 0 : _a.value) !== args.operationName) {
return;
}
const directives = [];
if (node.directives && node.operation === 'query') {
for (const directive of node.directives) {
if (directive.name.value === 'live') {
liveDirectiveNode = directive;
}
else {
directives.push(directive);
}
}
return {
...node,
directives,
};
}
return node;
},
});
if (liveDirectiveNode) {
const intervalArgNode = (_a = liveDirectiveNode.arguments) === null || _a === void 0 ? void 0 : _a.find((argNode) => argNode.name.value === 'interval');
let intervalMs = defaultInterval;
if (((_b = intervalArgNode === null || intervalArgNode === void 0 ? void 0 : intervalArgNode.value) === null || _b === void 0 ? void 0 : _b.kind) === Kind.INT) {
intervalMs = parseInt(intervalArgNode.value.value);
}
setExecuteFn((args) => new Repeater((push, stop) => {
let finished = false;
async function pump() {
if (finished) {
return;
}
const result = await executeFn(args);
if (isAsyncIterable(result)) {
push({
data: null,
errors: [new GraphQLError('Execution returned AsyncIterable which is not supported!')],
isLive: true,
});
stop();
return;
}
result.isLive = true;
if (finished) {
return;
}
push(result);
setTimeout(pump, intervalMs);
}
pump();
stop.then(() => {
finished = true;
});
}));
}
},
};
}