Task/add attribute metatadas and static attribute metadatas to jexl ctxt

[AlvaroVega]

Issue #1630

Implemented having into account:
telefonicaid/fiware-orion#4600

• Add test about metadata in jexl context

[mapedraza]

Should context also need to be updated while calculating metadata expressions here?

iotagent-node-lib/lib/services/ngsi/entities-NGSI-v2.js

Lines 506 to 537 in 49f8550

	// Expand metadata value expression
	if (currentAttr.metadata) {
	for (var metaKey in currentAttr.metadata) {
	if (currentAttr.metadata[metaKey].expression && metaKey !== constants.TIMESTAMP_ATTRIBUTE) {
	let newAttrMeta = {};
	if (currentAttr.metadata[metaKey].type) {
	newAttrMeta['type'] = currentAttr.metadata[metaKey].type;
	}
	let metaValueExpression;
	try {
	metaValueExpression = jexlParser.applyExpression(
	currentAttr.metadata[metaKey].expression,
	jexlctxt,
	typeInformation
	);
	//we fallback to null if anything unexpecte happend
	if (
	metaValueExpression === null ||
	metaValueExpression === undefined ||
	Number.isNaN(metaValueExpression)
	) {
	metaValueExpression = null;
	}
	} catch (e) {
	metaValueExpression = null;
	}
	newAttrMeta['value'] = metaValueExpression;
	currentAttr.metadata[metaKey] = newAttrMeta;
	}
	}
	}
	}

[mapedraza]

Would be great to add a test under JEXL section here:

iotagent-node-lib/test/functional/testCases.js

Lines 987 to 997 in 46ac1d8

	// 0100 - JEXL TESTS
	{
	describeName: '0100 - Simple group with active attribute + JEXL expression boolean (!)',
	provision: {
	url: 'http://localhost:' + config.iota.server.port + '/iot/services',
	method: 'POST',
	json: {
	services: [
	{
	resource: '/iot/json',
	apikey: globalEnv.apikey,

[fgalan]

Should context also need to be updated while calculating metadata expressions here?

iotagent-node-lib/lib/services/ngsi/entities-NGSI-v2.js

Lines 506 to 537 in 49f8550

	// Expand metadata value expression
	if (currentAttr.metadata) {
	for (var metaKey in currentAttr.metadata) {
	if (currentAttr.metadata[metaKey].expression && metaKey !== constants.TIMESTAMP_ATTRIBUTE) {
	let newAttrMeta = {};
	if (currentAttr.metadata[metaKey].type) {
	newAttrMeta['type'] = currentAttr.metadata[metaKey].type;
	}
	let metaValueExpression;
	try {
	metaValueExpression = jexlParser.applyExpression(
	currentAttr.metadata[metaKey].expression,
	jexlctxt,
	typeInformation
	);
	//we fallback to null if anything unexpecte happend
	if (
	metaValueExpression === null ||
	metaValueExpression === undefined ||
	Number.isNaN(metaValueExpression)
	) {
	metaValueExpression = null;
	}
	} catch (e) {
	metaValueExpression = null;
	}
	newAttrMeta['value'] = metaValueExpression;
	currentAttr.metadata[metaKey] = newAttrMeta;
	}
	}
	}
	}

Differently from attribute calculation (where there is an order based in array index) in the case of metadata we don't have such array, so we have to be careful if the calculation of one metadata depends on another calculated metadata in the same attribute. Maybe this such be warned at documentation.

[fgalan]

It seems this paragraph is the only new thing in documentation, all the rest seems to be re-formatting.

@AlvaroVega could you confirm, pls?

[fgalan]

Suggested change

	Attribute metadata and Static Attribute metadata are available in the **context** under the following convention:
	`metadata.AttributeName.MetadataName` or `metadata.StaticAttributeName.MetadataName` in a similar way of defined for
	[Context Broker](https://github.com/telefonicaid/fiware-orion/blob/master/doc/manuals/orion-api.md#metadata-support)
	Attribute metadata and Static Attribute metadata are available in the **context** under the following convention:
	`metadata.<AttributeName>.<MetadataName>` or `metadata.<StaticAttributeName>.<MetadataName>` in a similar way of defined for
	[Context Broker](https://github.com/telefonicaid/fiware-orion/blob/master/doc/manuals/orion-api.md#metadata-support)

Using the <...> syntax would make more explicit that they refer to actual names, different to metadata which is a literal token.

[AlvaroVega]

Yes, it is

[AlvaroVega]

Would be great to add a test under JEXL section here:

iotagent-node-lib/test/functional/testCases.js

Lines 987 to 997 in 46ac1d8

	// 0100 - JEXL TESTS
	{
	describeName: '0100 - Simple group with active attribute + JEXL expression boolean (!)',
	provision: {
	url: 'http://localhost:' + config.iota.server.port + '/iot/services',
	method: 'POST',
	json: {
	services: [
	{
	resource: '/iot/json',
	apikey: globalEnv.apikey,

Fixed in c8778c7

[AlvaroVega]

Should context also need to be updated while calculating metadata expressions here?

iotagent-node-lib/lib/services/ngsi/entities-NGSI-v2.js

Lines 506 to 537 in 49f8550

	// Expand metadata value expression
	if (currentAttr.metadata) {
	for (var metaKey in currentAttr.metadata) {
	if (currentAttr.metadata[metaKey].expression && metaKey !== constants.TIMESTAMP_ATTRIBUTE) {
	let newAttrMeta = {};
	if (currentAttr.metadata[metaKey].type) {
	newAttrMeta['type'] = currentAttr.metadata[metaKey].type;
	}
	let metaValueExpression;
	try {
	metaValueExpression = jexlParser.applyExpression(
	currentAttr.metadata[metaKey].expression,
	jexlctxt,
	typeInformation
	);
	//we fallback to null if anything unexpecte happend
	if (
	metaValueExpression === null ||
	metaValueExpression === undefined ||
	Number.isNaN(metaValueExpression)
	) {
	metaValueExpression = null;
	}
	} catch (e) {
	metaValueExpression = null;
	}
	newAttrMeta['value'] = metaValueExpression;
	currentAttr.metadata[metaKey] = newAttrMeta;
	}
	}
	}
	}

Done in 344cb5c

[AlvaroVega]

Differently from attribute calculation (where there is an order based in array index) in the case of metadata we don't have such array, so we have to be careful if the calculation of one metadata depends on another calculated metadata in the same attribute. Maybe this such be warned at documentation.

Done in a103f39

[mapedraza]

This if clause checks if the metadata exits into the original jexl context but, in the case of new metadatas generated as a result of expressions, it would not be included. I think It should be appended to the jexlctxt even if it was not part previously of it.

[AlvaroVega]

Fixed in 5da8640

[mapedraza]

LGTM

[fgalan]

LGTM