go.chromium.org/luci@v0.0.0-20240309015107-7cdc2e660f33/cipd/appengine/impl/repo/processing/processor.go (about)

     1  // Copyright 2018 The LUCI Authors.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //      http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package processing
    16  
    17  import (
    18  	"context"
    19  
    20  	"go.chromium.org/luci/cipd/appengine/impl/model"
    21  )
    22  
    23  // Processor runs some post-processing step on a package instance after it has
    24  // been uploaded.
    25  type Processor interface {
    26  	// ID is unique identifier of this processor used store processing results in
    27  	// the datastore.
    28  	ID() string
    29  
    30  	// Applicable returns true if this processor should be applied to an instance.
    31  	//
    32  	// Called as a part of the instance registration datastore transaction.
    33  	// Returns an error if the decision can't be made. It will result in
    34  	// a transient instance registration error.
    35  	Applicable(ctx context.Context, inst *model.Instance) (bool, error)
    36  
    37  	// Run executes the processing on the package instance.
    38  	//
    39  	// Returns either a result, or a transient error. All fatal errors should be
    40  	// communicated through the result.
    41  	//
    42  	// Must be idempotent. The processor may be called multiple times when
    43  	// retrying task queue tasks.
    44  	Run(ctx context.Context, inst *model.Instance, pkg *PackageReader) (Result, error)
    45  }
    46  
    47  // Result is returned by processors.
    48  //
    49  // It is either some JSON-serializable data or a fatal error.
    50  type Result struct {
    51  	Result any // JSON-serializable summary extracted by the processor
    52  	Err    error       // if non-nil, contains the fatal error message
    53  }