remove unnecessary complexity

hcl2template/types.datasource.go

@@ -102,25 +102,10 @@ func (cfg *PackerConfig) startDatasource(dataSourceStore packer.DatasourceStore,
 		})
 	}
 
-	// HACK:
-	// This is where we parse the variables being used in the data sources.
-	// By passing in the DatasourceContext variable, we tell the EvalContext
-	// that since this is a datasource being evaluated, we should not allow
-	// other data sources to be decoded into it. When secondaryEvaluation is
-	// true, we know that this data source needs another data source in order
-	// to be evaluated. So we instead retrieve a different EvalContext.
-	// This is a brute force method to enable data sources to depend on each
-	// other, and a more elegant solution will be available once we implement a
-	// true DAG for Packer.
 	var decoded cty.Value
 	var moreDiags hcl.Diagnostics
 	body := block.Body
-	if secondaryEvaluation {
-		// LocalContext is a lie! See above.
-		decoded, moreDiags = decodeHCL2Spec(body, cfg.EvalContext(LocalContext, nil), datasource)
-	} else {
-		decoded, moreDiags = decodeHCL2Spec(body, cfg.EvalContext(DatasourceContext, nil), datasource)
-	}
+	decoded, moreDiags = decodeHCL2Spec(body, cfg.EvalContext(DatasourceContext, nil), datasource)
 
 	diags = append(diags, moreDiags...)
 	if moreDiags.HasErrors() {

hcl2template/types.packer_config.go

@@ -118,18 +118,13 @@ func (cfg *PackerConfig) EvalContext(ctx BlockContext, variables map[string]cty.
 		},
 	}
 
-	// Currently the places where you can make references to other blocks
-	// from one is very 'procedural', and in this specific case, we could make
-	// the data sources available to other datasources, but this would be
-	// order dependant, meaning that if you define two datasources in two
-	// different blocks, the second one can use the first one, but not the
-	// other way around; which would be totally confusing; so - for now -
-	// datasources can't use other datasources.
 	// In the future we'd like to load and execute HCL blocks using a graph
 	// dependency tree, so that any block can use any block whatever the
 	// order.
+	// For now, don't add DataSources if there's a NilContext, which gets
+	// used with packer console.
 	switch ctx {
-	case LocalContext, BuildContext: // todo: refine
+	case LocalContext, BuildContext, DatasourceContext:
 		datasourceVariables, _ := cfg.Datasources.Values()
 		ectx.Variables[dataAccessor] = cty.ObjectVal(datasourceVariables)
 	}