refactor(aws/services): extract findOfferingID helpers to fit gocyclo budget

memorydb: extract scanMemoryDBOfferingPage (per-page offering scan with
mismatch guard) and isLastMemoryDBPage (terminal-page check) from
findOfferingID, mirroring the helpers already in the ec2 package.

ec2: extract buildEC2QueryFromRec (details type-assertion + payment-option
conversion + query assembly) from findOfferingID into a standalone method.

Both findOfferingID functions now sit at cyclomatic complexity ≤10.
No behaviour change -- pure extraction verified by 72 passing unit tests.

Author: cristim

providers/aws/services/ec2/client.go

@@ -393,6 +393,24 @@ func describeInputFromQuery(q ec2OfferingQuery, nextToken *string) *ec2.Describe
 	}
 }
 
+// buildEC2QueryFromRec extracts ComputeDetails from rec, converts the payment
+// option, and assembles the ec2OfferingQuery used by findOfferingID.
+//
+// Pulled out of findOfferingID to keep that function under the cyclomatic limit.
+func (c *Client) buildEC2QueryFromRec(rec common.Recommendation) (ec2OfferingQuery, error) {
+	details, ok := rec.Details.(*common.ComputeDetails)
+	if !ok || details == nil {
+		return ec2OfferingQuery{}, fmt.Errorf("invalid service details for EC2")
+	}
+	wantOfferingType, err := convertEC2PaymentOption(rec.PaymentOption)
+	if err != nil {
+		return ec2OfferingQuery{}, err
+	}
+	q := buildEC2OfferingQuery(rec, details, c.getDurationValue(rec.Term))
+	q.wantOfferingType = wantOfferingType
+	return q, nil
+}
+
 // findOfferingID finds the appropriate EC2 Reserved Instance offering ID.
 //
 // The input is built from typed first-class fields on
@@ -407,24 +425,18 @@ func describeInputFromQuery(q ec2OfferingQuery, nextToken *string) *ec2.Describe
 // execID is the purchase execution UUID for log correlation; pass "" when
 // calling outside of a purchase flow (ValidateOffering, GetOfferingDetails).
 func (c *Client) findOfferingID(ctx context.Context, rec common.Recommendation, execID string) (string, error) {
-	details, ok := rec.Details.(*common.ComputeDetails)
-	if !ok || details == nil {
-		return "", fmt.Errorf("invalid service details for EC2")
-	}
-	wantOfferingType, err := convertEC2PaymentOption(rec.PaymentOption)
+	q, err := c.buildEC2QueryFromRec(rec)
 	if err != nil {
 		return "", err
 	}
-	q := buildEC2OfferingQuery(rec, details, c.getDurationValue(rec.Term))
-	q.wantOfferingType = wantOfferingType
 
 	tag := execID
 	if tag == "" {
 		tag = "no-exec"
 	}
 	t0 := time.Now()
 	log.Printf("purchase[%s]: EC2 findOfferingID starting (instance=%s platform=%s tenancy=%s term=%s payment=%s)",
-		tag, rec.ResourceType, details.Platform, details.Tenancy, rec.Term, rec.PaymentOption)
+		tag, rec.ResourceType, q.productDesc, q.tenancy, rec.Term, rec.PaymentOption)
 
 	var nextToken *string
 	page := 0
@@ -435,7 +447,7 @@ func (c *Client) findOfferingID(ctx context.Context, rec common.Recommendation,
 		page++
 		if page > maxOfferingPages {
 			return "", fmt.Errorf("pagination cap reached after %d pages for EC2 %s %s %s (issue #688)",
-				maxOfferingPages, rec.ResourceType, details.Platform, rec.PaymentOption)
+				maxOfferingPages, rec.ResourceType, q.productDesc, rec.PaymentOption)
 		}
 		pageStart := time.Now()
 		result, err := c.client.DescribeReservedInstancesOfferings(ctx, describeInputFromQuery(q, nextToken))
@@ -446,7 +458,7 @@ func (c *Client) findOfferingID(ctx context.Context, rec common.Recommendation,
 		}
 		log.Printf("purchase[%s]: EC2 findOfferingID page %d: %d offerings in %s",
 			tag, page, len(result.ReservedInstancesOfferings), time.Since(pageStart))
-		if id := scanEC2OfferingPage(result.ReservedInstancesOfferings, wantOfferingType); id != "" {
+		if id := scanEC2OfferingPage(result.ReservedInstancesOfferings, q.wantOfferingType); id != "" {
 			log.Printf("purchase[%s]: EC2 findOfferingID found match on page %d after %s total",
 				tag, page, time.Since(t0))
 			return id, nil
@@ -459,7 +471,7 @@ func (c *Client) findOfferingID(ctx context.Context, rec common.Recommendation,
 	log.Printf("purchase[%s]: EC2 findOfferingID exhausted %d page(s) in %s -- no match",
 		tag, page, time.Since(t0))
 	return "", fmt.Errorf("no offerings found for EC2 %s %s %s after %d page(s) (issue #688)",
-		rec.ResourceType, details.Platform, rec.PaymentOption, page)
+		rec.ResourceType, q.productDesc, rec.PaymentOption, page)
 }
 
 // isLastEC2Page reports whether a NextToken indicates the terminal page.

providers/aws/services/memorydb/client.go

@@ -328,19 +328,13 @@ func (c *Client) findOfferingID(ctx context.Context, rec common.Recommendation,
 		log.Printf("purchase[%s]: MemoryDB findOfferingID page %d: %d offerings in %s",
 			tag, page, len(result.ReservedNodesOfferings), time.Since(pageStart))
 
-		for _, o := range result.ReservedNodesOfferings {
-			got := aws.ToString(o.OfferingType)
-			if got != wantOfferingType {
-				return "", fmt.Errorf("MemoryDB offering %s has payment option %q, want %q (rec: %s %s) -- API filter mismatch",
-					aws.ToString(o.ReservedNodesOfferingId), got, wantOfferingType,
-					rec.ResourceType, rec.PaymentOption)
-			}
-			log.Printf("purchase[%s]: MemoryDB findOfferingID found match on page %d after %s total",
-				tag, page, time.Since(t0))
-			return aws.ToString(o.ReservedNodesOfferingId), nil
+		if id, err := scanMemoryDBOfferingPage(result.ReservedNodesOfferings, wantOfferingType, rec, tag, page, t0); err != nil {
+			return "", err
+		} else if id != "" {
+			return id, nil
 		}
 
-		if result.NextToken == nil || aws.ToString(result.NextToken) == "" {
+		if isLastMemoryDBPage(result.NextToken) {
 			break
 		}
 		nextToken = result.NextToken
@@ -352,6 +346,37 @@ func (c *Client) findOfferingID(ctx context.Context, rec common.Recommendation,
 		rec.ResourceType, rec.PaymentOption, page)
 }
 
+// scanMemoryDBOfferingPage inspects a single page of DescribeReservedNodesOfferings
+// results and returns the first matching offering ID.
+// It returns ("", nil) when the page is empty or no offering matched; it returns
+// ("", err) on an API filter mismatch; it returns (id, nil) on a successful match.
+//
+// Pulled out of findOfferingID to keep that function under the cyclomatic limit.
+func scanMemoryDBOfferingPage(offerings []types.ReservedNodesOffering, wantOfferingType string, rec common.Recommendation, tag string, page int, t0 time.Time) (string, error) {
+	for _, o := range offerings {
+		got := aws.ToString(o.OfferingType)
+		if got != wantOfferingType {
+			return "", fmt.Errorf("MemoryDB offering %s has payment option %q, want %q (rec: %s %s) -- API filter mismatch",
+				aws.ToString(o.ReservedNodesOfferingId), got, wantOfferingType,
+				rec.ResourceType, rec.PaymentOption)
+		}
+		log.Printf("purchase[%s]: MemoryDB findOfferingID found match on page %d after %s total",
+			tag, page, time.Since(t0))
+		return aws.ToString(o.ReservedNodesOfferingId), nil
+	}
+	return "", nil
+}
+
+// isLastMemoryDBPage reports whether a NextToken indicates the terminal page.
+// The AWS SDK may return either nil or a pointer to an empty string for the
+// last page; both must end pagination so the loop does not issue a redundant
+// request (and risk a false page-cap error on borderline page counts).
+//
+// Pulled out of findOfferingID to keep that function under the cyclomatic limit.
+func isLastMemoryDBPage(nextToken *string) bool {
+	return nextToken == nil || aws.ToString(nextToken) == ""
+}
+
 // getDurationStringForAPI converts the term string to a duration value accepted
 // by DescribeReservedNodesOfferings (seconds as a string or "1yr"/"3yr").
 // The MemoryDB API accepts both numeric-seconds strings and year strings.