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Own transaction when raising an event

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This commit is contained in:
Uwe Klinger
2021-05-03 16:37:16 +02:00
parent eb4bc703dd
commit 98113c46fd
3 changed files with 35 additions and 14 deletions
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40
suppliers/srv/mashup.js
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@@ -26,26 +26,26 @@ module.exports = async()=>{ // called by server.js
admin.on (['CREATE','UPDATE'], 'Books', async ({data:{supplier_ID: supplierId}}, next) => {
// Using Promise.all(...) to parallelize local write, i.e. next(), and replication
/*
// ERROR: Reference integrity is violated for association "supplier"
if (supplierId) return Promise.all ([ next(), async()=>{
let replicated = await db.exists (Suppliers, supplierId)
if (!replicated) await replicate (supplierId, 'initial')
}])
else return next() //> don't forget to pass down the interceptor stack
*/
const replicateIfNotExists = async()=>{
let replicated = await db.exists (Suppliers, supplierId);
if (!replicated) await replicate (supplierId, 'initial');
};
let replicated = await db.exists (Suppliers, supplierId);
if (!replicated) await replicate (supplierId, 'initial');
return next();
if (supplierId) return Promise.all ([ next(), replicateIfNotExists() ])
else return next() //> don't forget to pass down the interceptor stack
})
})
// Subscribe to changes in the S4 origin of Suppliers data
// REVISIT: cds context is still from the UPDAT method when running in same programm, but should
// be a separate
S4bupa.on ('BusinessPartners/Changed', async msg => { //> would be great if we had batch events from S/4
let replicas = await SELECT('ID').from (Suppliers) .where ('ID in', msg.businessPartners)
return replicate (replicas.map(each => each.ID))
await new Promise( resolve => setTimeout( resolve, 1000 ));
const tx = cds.db.tx(msg);
let replicas = await tx.run(SELECT('ID').from (Suppliers) .where ('ID in', msg.data.businessPartners));
await replicateTx(replicas.map(each => each.ID), undefined, tx, msg);
await tx.commit();
})
/**
@@ -57,6 +57,7 @@ module.exports = async()=>{ // called by server.js
if (!Array.isArray(IDs)) IDs = [ IDs ]
// TODO: Doesn't work when running in same process with mocked API_BUSINESS_PARTNER
// TODO: Issue
let suppliers = await S4bupa.read (Suppliers).where(...([[]].concat(IDs).reduce( (where, id, index ) => { where.push(`${index>1 ? "OR ":""}ID = `, id); return where })));
//let suppliers = await S4bupa.read (Suppliers).where('ID in',IDs)
if (_initial) return db.insert (suppliers) .into (Suppliers) //> using bulk insert
@@ -65,4 +66,17 @@ module.exports = async()=>{ // called by server.js
))
}
async function replicateTx (IDs,_initial, tx, msg) {
if (!Array.isArray(IDs)) IDs = [ IDs ]
// TODO: Doesn't work when running in same process with mocked API_BUSINESS_PARTNER
// TODO: Issue
let suppliers = await S4bupa.tx(msg).read (Suppliers).where(...([[]].concat(IDs).reduce( (where, id, index ) => { where.push(`${index>1 ? "OR ":""}ID = `, id); return where })));
//let suppliers = await S4bupa.read (Suppliers).where('ID in',IDs)
if (_initial) return tx.insert (suppliers) .into (Suppliers) //> using bulk insert
else return Promise.all(suppliers.map ( //> parallelizing updates
each => tx.update (Suppliers,each.ID) .with (each)
))
}
}