Simplify more by removing custom hash

Signed-off-by: Yury Tsarev <[email protected]>

Author: ytsarev

README.md

@@ -64,7 +64,6 @@ spec:
 | Field | Type | Description |
 |-------|------|-------------|
 | `dataField` | string | **Required**. Field to monitor for changes (e.g., `spec.resources`) |
-| `hashAlgorithm` | string | Algorithm to use for hash calculation. Supported values: `md5`, `sha256`, `sha512`. Default: `sha256` |
 | `approvalField` | string | Status field to check for approval. Default: `status.approved` |
 | `currentHashField` | string | Status field to store the approved hash. Default: `status.currentHash` |
 | `detailedCondition` | bool | Whether to add detailed information to conditions. Default: `true` |
@@ -172,7 +171,6 @@ spec:
       kind: Input
       dataField: "spec.resources"
       approvalField: "status.approved"
-      hashAlgorithm: "sha256"
       currentHashField: "status.currentHash"
       detailedCondition: true
       approvalMessage: "Cluster changes require admin approval"

fn.go

@@ -3,10 +3,8 @@ package main
 import (
 	"context"
 	"crypto/sha256"
-	"crypto/sha512"
 	"encoding/hex"
 	"encoding/json"
-	"hash"
 	"strings"
 
 	"github.com/upbound/function-approve/input/v1beta1"
@@ -159,11 +157,6 @@ func (f *Function) parseInput(req *fnv1.RunFunctionRequest, rsp *fnv1.RunFunctio
 	}
 
 	// Set default values if not provided
-	if in.HashAlgorithm == nil {
-		defaultAlgo := "sha256"
-		in.HashAlgorithm = &defaultAlgo
-	}
-
 	if in.ApprovalField == nil {
 		defaultField := "status.approved"
 		in.ApprovalField = &defaultField
@@ -418,26 +411,17 @@ func (f *Function) extractDataToHash(req *fnv1.RunFunctionRequest, in *v1beta1.I
 	return data, nil
 }
 
-// calculateHash calculates hash for the given data using the specified algorithm
-func (f *Function) calculateHash(data interface{}, in *v1beta1.Input) string {
+// calculateHash calculates hash for the given data using SHA256
+func (f *Function) calculateHash(data interface{}, _ *v1beta1.Input) string {
 	// Create a JSON representation of the data
 	jsonData, err := json.Marshal(data)
 	if err != nil {
 		f.log.Debug("Error marshaling data to JSON", "error", err)
 		return ""
 	}
 
-	// Choose hash algorithm
-	var h hash.Hash
-	switch *in.HashAlgorithm {
-	case "sha512":
-		h = sha512.New()
-	default:
-		// Default to sha256
-		h = sha256.New()
-	}
-
-	// Calculate hash
+	// Calculate SHA256 hash
+	h := sha256.New()
 	h.Write(jsonData)
 	return hex.EncodeToString(h.Sum(nil))
 }

input/v1beta1/input.go

@@ -23,12 +23,6 @@ type Input struct {
 	// For example: "spec.resources"
 	DataField string `json:"dataField"`
 
-	// HashAlgorithm defines which hash algorithm to use for calculating hashes
-	// Supported values: "md5", "sha256", "sha512"
-	// Default is "sha256"
-	// +optional
-	HashAlgorithm *string `json:"hashAlgorithm,omitempty"`
-
 	// ApprovalField defines the status field to check for the approval decision
 	// Default is "status.approved"
 	// +optional

input/v1beta1/zz_generated.deepcopy.go

@@ -53,12 +53,6 @@ spec:
               DetailedCondition adds a detailed condition about approval status
               Default is true
             type: boolean
-          hashAlgorithm:
-            description: |-
-              HashAlgorithm defines which hash algorithm to use for calculating hashes
-              Supported values: "md5", "sha256", "sha512"
-              Default is "sha256"
-            type: string
           kind:
             description: |-
               Kind is a string value representing the REST resource this object represents.